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The summer field meeting, 24th July to 2nd August, 1938. The Harrogate district
353 THE
SUMMER TO
FIELD MEETING, 24th JULY 2nd AUGUST, 1938.
THE HARROGATE DISTRICT.
Report by the Directors: R. G. S. HuDSOX, D.Se., WILFRID EDWARDS, M.A., L. H. TONKS, M.Sc., and H. C. VERSEY, D.Se. meeting of the Association was primarily to study the 1 HISrelation and variation in the sedimentation of the Millstone Grit and Carboniferous Limestone, the various features of the Pennine Foothills due to the Vale of York Glaciation, and the Permian succession in Yorkshire. The headquarters of the meeting were at Harrogate. Members of the Yorkshire Geological Society and the Leeds Geological Association were invited to the meeting, and altogether forty-one members and friends attended. In the absence of Professor Hawkins, Mr. \V. D. Ellis, C.M.G., M.A., acted as President throughout the meeting. Sunday, 24th July. The Succession and Structure of the Harrogate Anticline. The party proceeded by train to Pannal, on the south-east side of the Harrogate Anticline, and walking west-north-west towards the axis, under the guidance of Mr. Edwards and Dr. Hudson, traversed a descending sequence of the lower beds of the Millstone Grits. The linear ridges made by the outcrops of the inclined grit beds give the area a distinctive topography, but later in the day it was observed that such features were entirely absent from the plateau tops owing to the filling of depressions by boulder clay. After examining sections in the Harrogate Grits members collected from an exposure in Upper Bowland Shale in Crimple Beck, 600 yards W.N.W. of Hill Top Hall. Fossils indicated an horizon in the C. malhamense sub-zone (E,). This is the first record of the sub-zone in the Harrogate area, and as such confirms the correlation of these shales with the Bowland Shales [21]. * Howe Quarry, Beckwith, afforded an excellent section of the Harrogate Roadstones and of the top of the underlying Middle Bowland Shales. Members of the party were very interested in the lithology of the Roadstones and some discussion took place as to the origin of the chert which forms the chief cement of the rock and which binds together the calcareous crinoid ossic1es. Dr. Hudson's view that the chert was of primary deposition [21} met with considerable dissent. Mr. Edwards mentioned an unpublished record by A. H. Green of moulds of Spirifer, Productus, and" a thing like Sacca• Numbers in Clarendon type refer to the references given in the preceding paper,
U
The
Geology of the Country around Harrogate," P. 329 et seq. PROC. GEOL.
Assoc.,
VOL.
XLIX.,
PART
4,
1938.
22
354
W. EDWARDS AND R. G. S. HCDSON,
mina carteri " from beds close under the Roadstones. The Middle Bowland Shales are almost entirely unexposed and have yielded no fossils, but the Harlow Hill Sandstone, the inferred equivalent of the Nettleber Sandstone of the Skipton Anticline [26) was well seen at Howgill Quarries. The probable position of an inlier of Lower Bowland Shale along the axis of the anticline is indicated by features here and to the north-east. A walk across the axis past the Sulphur Springs in the Harrogate Grits at Harlow Carr led to a beck cut into those grits; dips N.N.E. at angles up to 80° were seen. The magnificent ridge of Birk Crag displayed sections in the coarse Almscliff Grit at the top of the Harrogate Grits, and provided an extensive view of the country to the north, where the sharp outcrop of the Scargill Grit, and the less distinct feature made by the Lower Follifoot Ridge Grit, indicated the dying out of the steep folding of the anticline. The depth and youthful appearance of Oak Beck at the foot of Birk Crag is attributed by Kendall to glacial overflow through the John 0' Gaunt channel farther west. After tea the more active members of the party walked to Oakdale where, at Oakdale Farm, the Scargill Grit dipping N.W. at about 60° was examined. A traverse was then made across the Follifoot Grits and Cayton Gill Beds to Grange Brickworks where, by the courtesy of the Allied Brick and Tile Works, Limited, an examination was made of the shales in the quarry. These shales occur above the lowest member of the Brimham Grits. The floor of the quarry consists of a siltstone from which the shale has been stripped; members were very interested in the top surface of this siltstone which shows an almost perfect ripple-marked surface. Limy ironstone nodules had been collected into a heap in the quarry and in these numerous examples of Productus carbonarius were found. Other fossils included various gastropods and lamellibranchs. In the shales numerous examples of Lingula, so perfectly preserved that the colour banding is still visible, were found. A few feet above the base of these shales a marine band containing goniatites was collected from. It contained H omoceras striolatum and numerous Dimorphoceras and fixed the age of the shales as belonging to the Reticuloceras reticulatum zone (R 1 ) . W.E., RG.S.H. Monday, 25th July. The Middle Yoredale Inliers of Upper Nidderdale. The main purpose of the day's excursion was to visit, under the guidance of Mr. L. H. Tonks, the limestone inliers of Lofthouse and Limley which occur beneath the Millstone Grit and to recognize by their characteristic fossils that these limestones are the equivalent of the Middle Limestone of Wensleydale,
SU~DIER FIELD MEETING-HARROGATE DISTRICT.
355
thus proving, since the Main Limestone and its associated beds are absent, the unconformity of the Millstone Grit on the Yoredale Series. During the outward journey to Lofthouse by Pately Bridge Mr. Edwards recounted the salient features of the Nidderdale glaciation, as described by Kendall, Raistrick and Tillotson [57, 64, 66, 69J. While the distribution of boulder clay on the surrounding hills indicates a former invasion of the whole region by icc, during the latest (York-Escrick) stage of the glacial period Nidderdale was occupied by a local glacier, which, although feeble compared with the ice-streams in other dales, left obvious traces of its occupation in the form of valley bottom moraines and gravels, marginal deposits and lateral drainage channels. It made but slight modification to the topography. During the day attention was drawn to the hummocky moraines between Ramsgill and Glasshouses, the flat above Gouthwaite Reservoir attributed to silting up of a lake blocked by the moraines at Wath, the jumble of fragmentary terraces along the valley bottom showing features of valley trains laid down and dissected during successive periods of ice shrinkage, and the paucity of drift and the absence of well marked corries in the upper part of the Dale. Some difficulty was shown in accepting the competence of a glacier springing from such restricted gathering grounds to move several miles down the gentle gradient of the valley and to pile moraine up to nearly 1,000 ft. above a.D. on the hill slopes at Pateley Bridge, especially since the maximum recorded height of drift near the Dale top is only TAoO ft. a.D. [69, p. 217]. Invasion by an extraneous ice-lobe is discounted, however, by the absence of erratics from outside the dale. While lateral moraines were nowhere obvious during the visit there were seen at many points in the upper dale rude terraces high up on the valley sides showing apparent ice-contact slopes. Their resemblance to kame terraces' was pointed out. The motor coaches were left at Lofthouse and the party proceeded to Lofthouse Bridge. Here Mr. Tonks gave an account of the Middle Yoredales succession as it is exposed at the various inliers of Lofthouse, Limley and Angram [35]. Then a visit was paid to the exposure of Middle Limestone in the Nidd underneath Lofthouse Bridge. The limestone here is the Cockleshell Limestone, the middle division of the Middle Limestone. Various fossils were collected, including good specimens of Chaetetes and Palaeosmilia regia. This locality, 300 yards north of Lofthouse Station, is the type locality for this latter fossil. It was from here that it was first collected by Phillips.". I
Gravelly deposits formed on valley sides against the edges of stagnant ice.
See Salisbury
R. D', The Glacial Geology of New Jersey, Geol. Sura .. N.}., 1902, 121.
Phillips, J. r836. Illustrations of the Geology of Yorkshire. Limestone District, p. 201. PI. II, figs. 25 and 26. 2
PI. II. The Mountain
356
R.
G. S. HUDSO:;
A~D
W. EDWARDS,
The party was then conducted up the bed of the Nidd and Mr. Tonks pointed out the unconformable junction of the Middle Limestone with the overlying Basement (Grassington) Grit. The Millstone Grit succession was well seen on the western side of the valley where, above the Grassington Grit, there was a thick succession of shales capped by the Red Scar Grit, here occurring in two leaves. Old workings in the Woogill Coal which occurs between the two leaves of this grit were seen. It was noted that the thickness of shale on the side of the valley was marked by typical landslip topography, well seen at Puddle House. After lunch the party crossed the small inlier of limestone at Thorpe to the main Limley inlier, and at Goyden Pot the Cockleshell Limestone was again well exposed. Many of the members interested in this underground watercourse of the Nidd attempted a descent of the pothole. Lack of light, however, prevented them from going very far. The limestone of the Limley inlier is folded into a shallow anticline and so, proceeding north, the party worked down the succession from the Cockleshell Limestone to the Single Post Limestone, the lowest member of the Middle Limestone. Here. about 135 yards S.W. of Manchester Holes, a good section in a low cliff overhanging the river exposes limestone from which the members collected excellent specimens of Orionastraea garwoodi, a fossil characteristic of this horizon. After a brief visit to Manchester Holes Mr. Tonks conducted the party to the old railway cutting, where the Cockleshell Limestone was seen with numerous specimens of Gigantella gigantea, many of which were collected by the more enthusiastic members of the party. After tea at Middlesmoor a visit was paid to How Stean Beck where, in the upper reaches of the Beck, there is a good exposure of the Scar Limestone, the uppermost division of the Middle Limestone. The top posts of this limestone contained abundant nodules of A phralysia, calcareous algre which are common on the upper surface of many of the Yoredale Limestones. Above the Scar Limestone there is exposed a thick section of shale The shale contains underlying the Lower Five Yards Limestone. the usual Zaphrentis fauna with abundant Zaphreniis, Fenestella, Rhipidomella, Schizophoria and abundant small spinose productids. The deep gorge of How Stean Beck (Pi. 22, A) cut by solution in the Middle Limestone was visited and then members rejoined the coaches at Lorthouse, On the return journey hammers were put to a coarse terrace deposit, showing the rude, ungraded bedding of valley train material, at Riverside, Pateley Bridge. The gravel was associated with, and apparently banked against, banded silt and loam. RG.S.H., W.E.
tV
Iv Photo: G. Bingley.
Pholo: G. Rin:zley.
,\.-How
STEAK, l'PPER C\IDDERDALE.
B.-J ACKD.\\\'
c\ICK, TROLlERS GILL, .\PPLETREEWICK.
[To 11c,] p. 35(1.
SUMMER FIELD :MEETING-HARROGATE DISTRICT.
357
Tuesday, 26th July. The Millstone Grit Succession of Upper Nidderdale. By kind permission of the Bradford Corporation the day's meeting was devoted to the examination, under the guidance of Mr. L. H. Tonks, of that area of Upper Nidderdale now partially occupied by the Angram and Scarhouse reservoirs. Starting near Scar Village, Mr. Tonks took the party into the bed of the Nidd where sections showed the Millstone Grit resting unconformably on beds above the Middle Limestone. Then the tips from the excavation of the Scarhouse Reservoir were examined and on them numerous examples of a bed of grit with phosphatic nodules were found. This, Mr. Tonks explained, was the basement bed of the grit where it rested unconformably on the Middle Yoredales. From the hillside Mr. Tonks pointed out the features made by the various beds of the Millstone Grit [35, p. 247] and gave a general comparison of the grit succession with that of Harrogate. The party then climbed the hillside and at Tops Gill, 880 yards E.N.E. of Lodge Farm, an exposure of the Colsterdale Limestone was examined. [35, p. 250.] The limestone, about 6in. thick, was here very much decalcified and well deserved the name given to it by the old surveyors of " gingerbread limestone." Vigorous collecting by the party resulted in a complete fauna being obtained. In addition to Cravenoceras nitidum, Cravenoceras sp., A nihracoceras glabrum, Dimophoceras and various lamellibranchs, several examples of Eumorphoceras bisulcatum. were obtained. This last form, previously unrecorded from this horizon, solves one of the difficulties of the correlation of the Colsterdale Limestone with the beds further south. [35, p. 252.] A brisk walk took the party to the Angram Reservoir, and from there a rather perilous walk along the scarp of the Lower Five Yards Limestone enabled the party to reach a good section in that limestone, and from it the typical fauna was obtained. Perhaps the most notable find was a bed rich in a mutation of Zaphrentis enniskilleni. Then a shale section between the Lower and Upper Five Yards Limestones was examined. It was, however, disappointingly poor in fossils. Here, however, the Millstone Grit unconformity could be demonstrated since the Upper Five Yards Limestone, present in this section below the Millstone Grit, was, on the previous day's excursion, shown to be absent beneath the Millstone Grit at Lofthouse and Limley. The party then returned to the motor coaches at Angram, and after tea at Lofthouse made an early return to Harrogate. RG.S.H.
35 8
R. G. S. HCDSOX AXD
,Y.
EDWi\RDS,
Wednesday, 27th July. The Millstone Grit of the Simonseat Anticline and the Lower Carboniferous of the Greenhow Inliers, The motor coach took the party across Knaresborough Forest to Blubberhouses and from there northwards along the valley of the Upper Washburn to Hoodstorth. Here Dr. Hudson pointed out the features of the Simonseat Anticline and detailed the Millstone Grit succession from the Grassington Grits exposed on the crest of the anticline at Simonseat, to the Brimham Grits exposed in the troughs of the neighbouring synclines on Redlish and Whit Moors. He emphasized the importance of the area since it formed a link between the Millstone Grit succession of Upper Nidderdale on the Askrigg Massif and that of Harrogate in the Craven Basin. The first exposure to be examined was at Carlhow Stoop where the Cayton Gill Shell Bed was collected from. Next the area around Hoodstorth Bridge was visited by the permission of the Corporation of Leeds. Here the Cayton Gill Shell Bed and Siltstones and the beds below and above are well exposed. Many fossils were collected from these beds and great interest was shown in the peculiar sedimentation. It was suggested that these beds were the topset beds of a Millstone Grit delta. The party then walked along the Appletreewick road by Hey Slack, traversing the Cayton Gill and Follifoot Grit succession, to Foulgate Bank formed by the scarp of the Red Scar Grit. At the ford at Harding Wife Shaw this grit was seen again, repeated by a strike fault. A brisk walk then took the party across Pockstones Moor. where, at Little Pockstones, the Upper Grassington Grit forms a strong feature. From here Dr. Hudson pointed out the structure of the anticline showing that Little Pockstones, on the core of the anticline, was flanked on both sides by the scarps of the Red Scar Grit and succeeding beds. He also demonstrated the steep pitch of the anticline to the east and pointed out that on the crest of the anticline to the west the Lower Grassington Grit was exposed at Simons Seat where, above 1,550 ft., there were potholes communicating with the limestone below [8]. From here the moorland of tussocky grass was crossed with some difficulty and the party arrived at Birk Gill on the northern flank of the anticline, where an exposure in the shales above the Red Scar Grit contained a thin limestone with Craoenoceras nitidum and Eumorphoceras bisulcatum. There was no doubt that this limestone from its fauna and lithology was the equivalent of the Colsterdale Limestone seen on the previous day in Upper Nidderdale. It is, therefore, an important link in the correlation of the two areas.
SUMMER FIELD MEETING-HARROGATE DlSTRICT.
359
From here, in spite of sprained ankles and the desire for lunch, way was made through the thick bracken along the banks of the Washburn to Nar Hill, where there was well exposed a good example of one of the strong E.-W. faults parallel to the North Craven fault. The fault face and the fault breccia were well seen in section and it was agreed that the fault was a reversed fault thrusting the Red Scar Grit over the Rowan Tree Grit, a grit higher in the sequence. After lunch, Redlish Beck, in which there is a good section from the Lower Follifoot Grit to Cayton Gill Beds, was visited. The interest of this section lay in the exposure of shale, between the Follifoot Grits, containing a marine band with Homoceras beyrichianum, thus dating for the first time these beds as belong~ng to the H omoceras zone (H) of the Millstone Grit sueceSSIOn. Rather weary the party then rejoined the bus and proceeded northwards along Blackgate to the inliers of Carboniferous Limestone along the Greenhow anticline. Lack of time prevented a visit to the Great Scar Limestone of Duckstreet Quarry. Near Coldstones Quarry Dr. Hudson pointed out the structure of the area, emphasizing the fact that in the various inliers exposed beneath the unconformable Millstone Grit the limestone was of various ages [16 and 7]. At Coldstones Quarry, from limestone of D, age, members made an extensive collection of the corals so abundant in this quarry. Lonsdaleia floriformis, Dibunophyllum, Aulophyllum, Palceosmilia regia and numerous Lithostrotions were collected and great interest was shown in the band of algal nodules exposed near the top of the section. After a brief look at the Simonstone Limestone of Toftgate the coach made the difficult descent to Pateley Bridge. This steep descent into Nidderdale at Bewerly was coincident with a spectacular change in glacial topography. Morainic mounds, conspicuous by their absence from the Greenhow area, suddenly appeared in profusion below 1,000 ft. a.D., marking with precision the southern limit of deposition of the Nidderdale glacier. Some indication of lateral drainage was seen at the upper edge of the moraine belt, and lower down the hill, at about 700 ft. a.D., a characteristic lateral channel, cut partly in moraine, was visible from the road. Returning to Harrogate, members of the Field Meeting were received by the Mayor and Mayoress of Harrogate and entertained to tea by the Harrogate Corporation. After tea Mr. Woodmansey, the Borough Analyst, gave a brief talk to the members on the Harrogate wells and then conducted the party into the Valley Gardens, showing them the sites of the various springs. RG.S.H., W.E.
w.
EDWARDS AND R. G. S. HUDSON,
Thursday, 28th July. The Coal Measures South of Leeds. A start was made at 9 a.m. to visit the Coal Measures of the Leeds-Normanton area. Between Harrogate and Leeds the coach traversed the full succession of Millstone Grits, and the main features of the area were pointed out, notably the ridge of the Almscliff Grit along the south-east flank of the Harrogate Anticline from Pannal to Great Alms Cliff, the wide expanse of Sabden Shale around Weeton and the easterly swing of the Follifoot Ridge Grits under the influence of the Wharfe Anticline, the east-west scarps of Follifoot Ridge Grits, Kinderscout and Middle Grits south of the river Wharfe, and finally the ridge of the Rough Rock as the Coal Measures are approached in the northern purlieus of Leeds. At Hawksworth Wood Quarries, Horsforth, the courtesy of Messrs. B. Whitaker & Sons Ltd. enabled the party to examine an extensive section of Rough Rock and overlying Coal Measures. The massive grits of the Rough Rock are parted from the fireclay of the Pot Clay Coal by several feet of variable mudstone, siltstone and uncemented sand rock. The fireclay itself is surmounted by barely an inch of coal, and the succeeding dark mudstones of the Coal Measures contain marine fossils including Gastrioceras subcrenatum, nautiloids, Lingula mytiloides and other brachiopods, lamellibranchs, gastropods and fish scales, scattered through several feet of measures and representing the well-known Pot Clay Marine Band. Boulder Clay occurs at the top of the section and yields sand-blasted stones at the surface. From Horsforth the route lay through Leeds to Thorp-on-theHill, near Robin Hood, where Messrs. George Armitage and Sons Ltd. kindly allowed an examination of the classic section in their brick pit (PI. 23, B). The Haigh Moor coals, with overlying richly fossiliferous measures of an abnormal type are exposed in an immense excavation, and have yielded a large fauna and flora. After examining the quarries in the Thornhill Rock, the members devoted some time to a heap of ironstone nodules from which they collected various plants. Dr. Hudson then pointed out the lie of the beds in the Coal Measures quarry, and explained the evidence for the fault to the north of it. A start was made in the examination of a succession in the beds below the Lower Haigh Moor Coal and from there numerous examples of N europteris heterophylla were obtained. A good section in the Upper Haigh Moor Coal and its underlying fireclay was then examined, and some discussion took place on the origin of the cleat which was well shown in this section. Old mine workings in the Upper Haigh Moor Coal were well exposed,
PROC. GEOL.
Assoc.,
VOL.
XLIX. (1938).
PLATE
23.
A.-\VHARFEDALE FHO:lI OTLEY CHEVr,.,;.
2\IEASVRES, EOBl!' HOOD QVARRY, LEEDS.
[To face p. 360 .
SUMMER FIELD MEETING-HARROGATE DISTRICT.
361
and it was noticed that there had been a settling of the beds above these old workings resulting in small downward folds of the thin coal above. Above the Upper Haigh Moor Coal further ironstone nodules were broken and yielded good specimens of N europteris gigantea and Lepidophloios. A visit was then paid to the Carbonicola beds [36J and many examples of Carbonicola aquilina and Anthracomya modiolaris were obtained. In the sandstone at the top of the succession a fossil tree trunk was noticed standing upright with its skin of bright coal still in place. Proceeding from Robin Hood through Whitwood to Altofts, the party saw abundant evidence of colliery activity. It was explained that the West Yorkshire Coalfield comprises over 4,000 ft. of measures, lying nearly fiat but considerably faulted, with many thin seams and some 10 to IS workable seams spread over a vertical distance of some 2,600 ft. At West Riding and Silkstone Colliery the party were met and welcomed by Mr. O. H. Jones, Secretary and Director of Messrs. Pope & Pearson Ltd., by Mr. J. E. Waring, Manager, and Mr. N. E. England, Surveyor. Before descending the pit they inspected a scale model, constructed by Mr. England, showing the geological structure of the area. Of the 9 to 10 seams worked at the colliery three were seen during a lengthy tour of the workings. The Warren House Coal was first inspected in order to see a seam with normal roof, being worked longwall with coal cutters. The Stanley Main workings were then entered in order to see roof shales with fossil plants and "pot holes" (erect internal casts of large lycopod stems cased with vitrain representing the original bark.) Chief interest centred in the "rock faults" exposed in roads close to the edge of a washout area in the Haigh Moor Coal. A prominent feature of the sections seen was the irregular interleaving of sandstone with coal in the seam and with mudstone in the roof: such phenomena are common near washout areas where sandstone forms the washout filling, but as yet lack adequate explanation. Equally prominent were the true " rock faults," irregular masses of sandstone, mudstone and coal, and of the interleavings mentioned, jumbled together in gigantic breccias. The junctions of dissimilar fragments in the breccias usually showed angular and slickensided surfaces; occasionally sandstone showed smoothly folded and creased surfaces against which the weaker mudstone and coal was crushed. One large sandstone mass had been intensely folded before itself becoming part of the breccia. The folding and brecciation are attributed [11, and Fearnsides, W. G., Trans. Inst. Min. Eng., L, 1916, p. S83J to stresses during compaction of the washout filling (Haigh Moor Rock)
W. EDWARDS A::\D R. G. S . H UD SO::\,
a nd of the underlying sediments, lateral squeezing being at a m aximum on the sides of the washouts. Duplicat ion and even triplication of seam by lateral thrust ing ar e occasional result s of such movemen t s, and the charac teristic example figured from the present pit by Professor Fearnsides was still part ly visible. The fact that br ecciation had preceded the cleating of th e coal was noted . Whil e the party were undcrgound th e ladi es were shown the surface plant and t ak en down t o th e Beeston seam at 1,487 ft. to see the layout of the pit bottom and the pit ponies. Members were enterta ined t o t ea by the Company , and ga ve a hearty vot e of th anks t o ':.\Ir. J ones and other members of t he st aff for their kindness. The return journey was mad e with out stop, a projected visit to the new Mount Pleasant sinking of Messrs. T . and R. 'V. Bower Ltd., having to be abandoned owing to shortage of time. W.E., R.G .S.H . Friday, 29th July. The Millstone Grit North-west of Harrogate and the Glacial Features of the Fountains District. Th e party left the motor-coach at Little Alms Cliff . and from th is view-point were shown the t opographic features of the south-western part of the H arrogate Anticline. H ere the axial zone is occupied by a broad out crop of the lower part of the H arrogate Grits, with the Almscliff Grit forming a flanking rid ge on either side. The drift of this are a is a featureless spread of boulder clay , locally thick on the hilltops and abs ent from the v alleys; it is at least as old as the early Main Dales Glaciation, and may be Older Drift. To the north of Little Alms Cliff Dr. Huclson pointed out the various scarps due to t he succession of Scargill Grit, Follifo ot Grits, Cayton Gill Beds and Brimham Grits and emphasized t he folded nature of th e Knare sborough F orest country to the north, pointing out th e lie of the Beam sley and Simon seat Anticline. To the far north the highlan ds of the Askrigg massif could be just seen. To the north-east over H arrogate there was a good view of the Vale of York and the Cleveland Hill s. By permission of lVIr. West, the party were then taken across H averah Park, the catchment ar ea of Harrogate Reservoirs. South of Scargill Reservoir a good section in the shales above the Scargill Grit was seen. Decalcified limestone in these shales contained good specimens of Crauenoceras nitidum and Eumorphoceras bisulcatum, leaving no doubt in the minds of the party that this bed was the equivalent of the Colste rdale Limestone of Up per Nidderdale and t he Birk gill Lime stone of the Simonseat Anticline. It wa s emphasized that it was only by mean s of such
SliMMER FIELD :MEETING-HARROGATE DISTRICT.
363
faunal bands, lithologically unimportant, that the correlation of these big thicknesses of grits could be established. Further along Scargill Beck a section between the Lower and Upper Follifoot Grits was visited, and here a bed of limy ironstone contained good examples of Dimorphoceras and Posidoniella laevis. Although an unsuccessful search was made for H omoceras beyrichianuni which should occur near this level, a band of nodules containing abundant "Yucula was discovered. Rejoining the bus at Penny Pot Lane the party rapidly traversed the featureless drift-covered country of that area and arrived at the section in the shales near Victoria House, Hampsthwaite. These shales, whose exact stratigraphical position has not yet been determined, contained bullions with Crauenoceras edalense and Crauenoceras subplicatum, for which latter form this section is the type locality [3]. Good examples of these, together with Eumorphoceras bisulcatum and Anthracoceras sp. were found. After lunch in Hampsthwaite and a visit to the old church the party crossed the Nidd to the famous quarry in the Cayton Gill beds near Clint. In the shell bed near the top of the exposed succession good examples of Productus carbonarius, Derbyia gigantea and Schizophoria hudsoni were collected. After a successful rat hunt in Clints Ouarrv the bus was rejoined and took the road past Brimhar'; Rocks, the finest group of weathered stacks in the district. General opinion favoured Pleistocene wind action as the originator of the present forms of these rocks, and it was pointed out that this action was probably later than the early part of the Main Dales Glaciation, since the ice at that period probably covered the interstream areas on the flanks of the Pennines. It was also suggested that since these and other groups of stacks throughout the Pennines tended to occur only on hilltops, they were relics of more extensive areas of weathered rock which had been removed from sloping areas during the last glacial phase, either by snow-field creep or by solifluxion (PI. 24, B). Proceeding across Sawley Moor, the party saw the Eavestone channel on the left and the conspicuous intake of the Picking Gill channel on the right, two overflows related to the highest defined stand of the Vale of York glacier during the YorkEscrick Stage. Farther east and at a lower level, the next ice-front stand, as defined by Kendall and Wroot, was seen to be marked by a massive belt of moraines and kames fringed with the sequence of large overflows at Sun Wood, Spa Gill and The Dene, in line with the Laver diversion to the north. A quarry at Clip'd Thorn showed a face of gravelly moraine which yielded, besides the abundant Carboniferous erratics, igneous rocks comparable
w,
EDWARDS AND R. G. S. HUDSON,
with Cheviot porphyrites, Whin Sill dolerite and Lake District volcanics. Shap Granite is recorded here by Raistrick. Complex drainage phenomena were seen in this region, where, according to Raistrick, the northern (Teesdale) ice has swung westward on to an area being cleared of Pennine ice, with consequent adjustment in lateral drainage. A halt was made at Fountains Abbey for tea and to see the ruins. Here the party were joined by Sir Arthur and Lady Smith Woodward. Then the road was taken past Morker, where the moraine topography was particularly fine, to Haddockstones. An extensive flat was seen to mark the site of the Hebden Beck lake, which received during successive retreat stages the waters from Picking Gill and The Dene, and overflowed through Cayton Gill (Pl. 24, A). A halt was made in Cavton Gill near Dole Bank, where the characteristic features of this great overflow were seen to perfection. The lateral moraine was crossed on the road to Markington, and again approaching Ripley, where the road descended from it on to the gravel flat explained by Kendall and Wroot as the delta of Cayton Gill. A recent road-cutting near Ripley Valley Station gave a section in the river-cut edge of this flat. Gravel with a basal layer of false-bedded sand lay abruptly on a thick series of thin bedded clay, silt and loam, such as might have been deposited here in the glacial lake whose overflow cut the Knaresborough Gorge. The wide valley of the Nidd at this point was contrasted with its channel-like gorge farther east. A short journey took the party back to Harrogate. W.E., RG.S.H. Saturday, 30th July. The Great Scar and Reef Limestones of the Burnsall Anticline.
To-day's excursion was devoted to the study of the limestone exposed in the Burnsall Anticline, particular attention being devoted to the passage of the Great Scar Limestone into the Cracoe Reef Limestone and also to the topography and structure of the Reef Knolls. The journey to the Burnsall area was made via Bolton Abbey and Barden Towers. The first stop was made near Intake Plantation, where an extensive view was obtained of the Wharfe Valley from Burnsall to Skyreholme, and here Dr. Hudson pointed out the main features of the area, demonstrating the course of the North Craven Fault and emphasizing that it was in this area that there was a sharp change from basin to massif sedimentation and that the Carboniferous Limestone was here 'Of the marginal facies. In the same way he pointed out that it was in this area that the passage from the Lower Bowland Shales to the Lower Yoredale Series could be proved.
Pnoc. GEOL. Assoc., VOL. XLIX. (1938).
A.-·GLACIAL :\r."RGINAL CHAl-il"EJ..
PLATE 24.
C ·\YTON CILl..
B,-\\'!l';D-ERODED :\IULSTO:"'E GRIT. 131'1:11clAM, ~Tn
[ace p. 3(q·.
SUMMER FIELD l\1EETlNG-H,\RROGATE DISTRICT.
365
The journey was continued to Middle Skyreholme and there Dr. Hudson pointed out the position of the syncline between the Simonseat Anticline and the Skyreholme Anticline and called attention to the valley of Blands Beck occupying the trough of the syncline. The party then proceeded along the valley of Skyreholme Beck, cut through the steeply southwarddipping Basement Grit, to near Percival House, where the junction of the grit and the limestone was demonstrated. Proceeding into Trollers Gill the party examined the limestone, noted its bedded character and its finely fragmental nature and agreed that it was of Great Scar facies. The topography of Trollers Gill was noted as an example of underground solution and collapse and considerable interest was taken in the springs which issued on the floor of the Gill, discussion taking place as to their origin and the reason for such a level of the water table. Next, the party worked its way along Jackdaw Nick (PI. 22, B), an example of the more recent collapse of the roof of an underground water course. Here the overhanging sides of the gorge were readily seen. Returning around Middle Hill the party entered the neighbouring gorge of Gill Beck and proceeded to Gill Head Lead Mine, where good yellow fluorspar and some galena were collected. Most members proceeded some short way into the workings, and here Mr. Eastwood gave a short talk on the method of working. The actual vein worked in this mine was well seen. Then Dr. Hudson discussed the age of the Iimestone and showed that the fossils dated it as belonging to the zone DrHe then took the party to Hell Hole, a pothole exposing the top of the limestone with a band containing Girvanella nodules. The upper part of the gorge of Skyreholme Beck was visited and the northern flank of the anticline well seen. Here the top of the Great Scar Limestone and the base of the Millstone Grit were pointed out and it was seen that between them there could only be a comparatively small thickness of beds. These beds, not well exposed, are intermediate in facies between the Lower Bowland Shales and the Lower Yoredales. The best exposure was seen at New Dam, where the Black Hill Limestone [1] aroused considerable interest as a condensed shelly limestone deposit. From this limestone good examples of Lonsdaleia floriformis, Chaetetes and Lithostrotion were collected proving the limestone to be of D, age, the equivalent of the limestone of Coldstones Quarry seen on a previous excursion. Then moving to the road, the grit of Fancarl Crag was well seen with the Great Scar Limestone exposed at the same level in a quarry behind it. The two exposures are separated by the North Craven Fault. Returning to Appletreewick the party rejoined the coach and proceeded to Badger Lane beyond Burnsall. Here Dr. Hudson pointed out the various knolls of Reef Limestone such as Byra
366
R. G. S. Hl'DSO:'\, W. EDWARDS AND H. C. VERSEY,
Bank, Thorpe Kail and Elbolton (PI. 25, B) and showed how the Bowland Shale rested on the limestone, and that the junction between the shales and the reef limestone was a very sinuous one, wrapping round the knolls. In 'Waterspout Beck Mr. Black demonstrated the Lower Bowland Shale succession and pointed out a limestone boulderbed in the shales. Returning to Badger Beck some discussion took place as to the origin of the isolated mass of limestone exposed in the beck. It was suggested that it was either an immense boulder in the shales, or, better still, a stack of limestone protruding through the shales. Lack of time prevented an examination of the limestone of Thorpe Kail and the party proceeded immediately to Elbolton, where a small quarry on the south-eastern flank yielded an abundant fauna of typical wellpreserved reef fossils. The more active members of the party climbed Elbolton and examined Navvy Noodles Hole, a pothole which, excavated in the latter years of the last century, yielded bones of many vertebrates. The origin of this pot hole at rr25 ft. a.D. on the top of Elbolton is a subject for much discussion. Dr. Hudson pointed out that it may have arisen when the greater part of Elbolton was covered with shale, forming a gathering ground for the water which made its escape through the limestone thus forming the pothole. The other members of the party made their way around Elbolton and took great interest in the topography of Stebden Knoll (PI. 25, A). Here the outcrop of shale completely surrounding the Knoll could be inferred from the distribution of rushy vegetation of the shale and the short grass of the limestone. It was seen that the Millstone Grit of Rylstone Fells if continued would rest directly on Stebden Knoll completely overlapping the Bowland Shales. At Linton Dr. and Mrs. Raistrick kindly entertained the party to tea and later Mr. Eastwood voiced the thanks of the party for their hospitality. Since it was now very late the party returned straight to Harrogate omitting the visit to both The Strid and Bolton Abbey. . RG.S.H. Sunday, 31st July. Knaresborough and Tadcaster. Travelling by road to Knaresborough, the party reached the Castle, perched above the winding limestone gorge occupied by the Nidd. Upstream there is about three miles of gorge, cut mainly in Millstone Grits and more truly an overflow channel, since at Knaresborough the glacial water has evidently only accommodated itself to an existing valley system, traces of which remain in the asymmetry of the gorge and in the mature valley of Holbeck, which runs into the Nidd from the south.
I'ROC. GEOL.
Assoc.,
VOL.
. \. --STEIlDEJ-;
XLIX. (1938) .
PLATE
25.
I"'~OLL, "'EAR CRACOE.
13,-ELBOLTON KNOLL, NEAR CRACOE.
Photo: F. S. Pintold, C.-GNCOXFOR\IABLE ]UKCTIO-r-: OF ~IAGKESIA~ LL',IESTOKE AND :\IILLSTOXE
GRIT,
KKARESBOROUGH.
Se\DlER FIELD ~lEETING-HARROGATE DIST1UCT.
J67
An examination was then made of the very fine section exposed on the north side of the gorge. Here the stained Brimham Grit with a fossil tree is truncated by the unconformable base of the Lower Magnesian Limestone (PI. 25, C). Attention was drawn to the sandy nature of these lower beds and to the presence of local re-crystallisation. A detour was made to the Dropping 'Well, where an extensive tufa screen composed largely of calcium sulphate is deposited by a spring emanating from the limestone. After some of the party had performed the usual ritual at the Wishing Well the journey was continued down Abbey Walk where rough concretionary structures and magnesium sulphate efflorescences were seen. Near Abbey House the limestone was seen bedded over elevations of the underlying grit. Near Grimbald Crag, after examining the nature of the pebbles in the Brimham Grit, members again saw the unconformity, its position on the Crag being due, in part, to an eastwest fault. This fault was seen in a neighbouring quarry throwing limestone against the Middle Marl. The pebbly nature of the lowest bed of limestone was taken as pointing to the presence under the quarry of a "knob" of grit. Higher up the limestone shows a wedge-bedding characteristic of the upper beds of the Lower Magnesian Limestone. Below Grimbald Bridge a gravel spread is delta-bedded as if by water issuing from the Knaresborough Gorge, but at Goldsborough Mill there is again a rock-gorge, and from here to Ribston the Nidd hugs the edge of the rising ground to the west, and has cut into the solid rock in places, as if under the influence of a neighbouring ice-edge. There is some evidence of a small marginal lake along this part of its course, for laminated clay overlain by fine, well graded gravel, was seen close to the river at Scaliber. Moraine deposits were not obvious between Knaresborough and Ribston, but appeared at North Deighton east of the large, flat-graded Kirk Deighton channel. At Wetherby the party got a sight of the intake of the Wharfe diversion, and saw the wide, flat-floored valley higher up, where sections have revealed beds of laminated lake-clays. Near Wattle Syke, Collingham, a gravel pit was seen in coarse, kame-like material, forming part of a sharp ridge with a steep side facing north-east and suggesting an ice-contact slope. This ridge is one part of an interrupted line of similar gravels, trending south-eastwards through Linton and Bramham and continued by the gravels seen later in the day near Wingate Hill. Recently observed and not yet mapped in detail, it is in all probability an ice-front deposit of the Vale of York glacier, parallel with and about two miles outside of the line of the Escrick Moraine.
W. EDWARDS AND H. C. VERSEY,
Continuing the journey to Boston Spa, the bus halted at Ingle Bank, where a disused quarry showed terrace gravels of the Wharfe, now under investigation. A sudden change in water level, perhaps the effect of ice-blockage, was suggested by the abrupt upward transition from gravel to loam. This latter material contained masses of angular Head, derived from the hillside above and containing fragments of shelly Upper Magnesian Limestone. Many of these fragments were sand-blasted, and led to a discussion on the close connection between soliftuxion and wind-action as evidenced by the late glacial drifts in Yorkshire. At Wingate Hill above Tadcaster members were indebted to Messrs. Aberford Quarries Ltd. for facilities to examine their gravel pit, now extended into a large excavation. The material worked forms a ridge on the hilltop with a steep northward facing edge, and is a mixture of coarse unsorted gravel, sand, loam and bedded clay, showing much sharp disturbance and having the general appearance of a kame deposit. Permian limestone abounded and tended to form large ice-scratched boulders, Carboniferous sandstone and limestone were common and a few far-travelled erratics were found, including rocks resembling Whin Sill dolerite, Cheviot porphyrite, with quartzite and one piece of mica-schist. A similar section was afterwards seen, through the courtesy of Messrs.]. H. Walker and Co. Ltd., at Stutton Gravel Pit farther down the hill, the gravel and sand showing bedding towards the south with much disturbance amounting in places to overfolding. A short walk led to Towton, where tea was enjoyed. Afterwards the gravel pit at the south end of the village showed a characteristic section in the 100 ft. Strand Line gravels. Coarse boulder beds and gravels, consisting of local Magnesian Limestone were seen resting on a smooth surface sloping gently eastwards, while evidence formerly visible showed that in that direction they pass laterally into limestone sands. Later a section in the same beach gravels at Garnet Lane, Tadcaster, showed coarse shingle with underlying sand resting on a sloping rock surface blanketed with Head. The return journey was made through Plumpton, where the Brimham Grit is weathered into erosion stacks similar to those at Brimham Rocks. The propinquity of the overlying Magnesian Limestone caused some speculation as to the possible prePermian age of the stacks. W.E., H.C.V. Monday, 1st August. Ripon and Masham. The party left headquarters by bus for Wormald Green. Here the Magnesian Limestone is worked in a large quarry which shows
SUMMER FIELD MEETING-HARROGATE DISTRICT.
369
the upper beds of the Lower Limestone. Satisfactory discrimination between the Lower and Upper limestones is not possible in this area, but in the quarry two feet of a grey marl is exposed. Some discussion ensued as to the possibility of this being a residue from limestone solution, but the limestone itself shows the cellular structure due to solution of ooliths which is common in South Yorkshire under the Middle Marls. Extensive stalagmitic deposits were also seen in joints and cavities in the south of the quarry. Overlying the limestone was boulder clay with a profusion of scratched Carboniferous Limestone blocks, and appearing to represent true ground-moraine. The journey was then continued to Ripon Station. On the Thirsk road, just north of the station, an old quarry in Bunter Sandstone was examined and proved to reveal alternations of red and yellow sandstone of medium grade with some indications of wind deposition. The colour variation was attributed to variation in water level during deposition. Certain circular depressions were then seen in fields by the railway. These are attributed to solution of gypsum in the underlying Upper Marls, and in one of the pits the Bunter was seen. It was pointed out that although many of these came into existence some sixty years ago, the area is apparently stable at present. Continuing on the Masham road, the party left the bus at North Lees and proceeded by field paths to the riverside, where the Upper Marls are well exposed. The marls owe their presence here to a pair of faults crossing the Vale of York. Near the base of the section about IS ft. of massive gypsum is exposed and is regarded as the equivalent of the well-known anhydrite bed revealed in borings. Above it the marls are extensively contorted with beds of fine satiny gypsum. In view of the uniform orientation of the gypsum crystals, it was felt that the formation of the minerals must be a secondary phenomenon associated with the contortion while still later deposition is shown by thin veins occupying faults and showing a different orientation. Rejoining the bus the party saw the site of a Roman defended house at Castle Dikes and at West Tanfield wide gravel terraces which lie at three levels and which are related by Raistrick to recessional moraines higher up the Ure valley. During an interval here for lunch members visited the Marmion antiquities, after which the journey continued via the Bronze Age camps at Thornborough to Well Scar limestone quarry. Here an unusual facies of the Lower Magnesian Limestone was seen yielding Producius horridus in its lowest beds. The rock exposed is grey in colour and very reminiscent of compact Carboniferous limestone. Concretionary layers are frequent, but fossils in these are rare. It was pointed out that the Magnesian Limestone in this area is thickening due to the presence of these Pnoc,
GEOL.
Assoc.,
VOL.
XLIX.,
PART
4, 1938.
23
370
H. C. VERSEY, \V. EDWARDS AND R. G. S. HUDSON,
lower beds which are possibly overlapped farther south. From the top of the quarry opportunity was taken to point out the continuation across the Vale of York of the trough faults mentioned above into the Coxwold Gap. Here also, removal of the overlying boulder clay has exposed a wide stretch of glaciated pavement, with strise trending a few degrees east of south. After passing Masham members were met by Major Douglas Collins and conducted to view points in the grounds of Hack Fall to see the magnificent gorge of the River Ure, a lateral channel cut in rock during a late stage of retreat of the Wensleydale glacier. Major Collins exhibited specimens of tufa deposited by a spring on the hillside in a manner analogous to that of the Dropping Well, Knaresborough, and received a vote of thanks from the party. Leaving Hackfall the route layover an area of large hummocky hills around Grewelthorpe. A large opening at the east end of the village showed rudely bedded coarse gravel more resembling kame than moraine material, and it is probable that many of the gravelly hills in this area, usually referred to as moraines, will prove on investigation to be kames. The road from Grewelthorpe to Ripon crossed the large dry trench of Thieves Gill, a long marginal valley related to the diversion of the Ure at Hackfall. Tea at Ripon was followed by a journey via Ripley to the large quarries of Messrs. XL Gravels Ltd. at Lingerfield, near Scotton. These showed gravel of glacial outwash type, coated in places with manganese dioxide, and overlain by boulder clay. This superposition might be accounted for in a variety of ways, most easily perhaps by a slight oscillation of the ice-margin. The party returned thence to Harrogate.
RC.V., W.E. Tuesday, 2nd August. The Glaciation and Millstone Grit Succession of the Wharfe Valley. Leaving Harrogate the party took bus to Stonefall Brick Works at Woodlands, where Messrs. Allied Brick and Tile Works permitted examination of the section. The Weeton Shales here contain nodular limestone masses with Cravenoceras and Anthracoceras. A peculiar feature of the section was the uniform downward penetration to about 25 ft. of purple-red staining affecting both mudstone and nodules. This was ascribed to pre-Permian desert conditions, since the Permian lies only half a mile away to the east. A traverse of the rib-like outcrops of the Follifoot Ridge Grits brought the party to Spofforth Haggs Quarry; here a cherty facies of Cayton Gill Beds was seen to be less fossiliferous than that
S1.nr:vIER FIELD MEETI:\G--HA.RROGATE DISTRICT.
371
at the eponymous locality. The outcrop was shown to lie in a broad syncline between the Harrogate and Wharfe anticlines, the south-westerly rise of the Follifoot Ridge Grits under the influence of the latter fold being conspicuous. The route led across Follifoot Ridge and the broad depression of the Weeton Shales at Pannal to Great Alms Cliff, which was ascended. Some discussion of the peculiar features of this hill took place, and the opinion was expressed that its development as a huge crag rising high above the subdued outlines of Rigton Ridge lay partly in original structure,' partly in subsequent erosion in which the Pleistocene ice-sheets took part. Shortage of time led to the abandonment of part of the original programme, and the bus continued past Staniston Hill, an isolated kame marking the probable limit of the last Wharfedale glacier, to the bank top above Leathley. The road descending to the village crossed a series of lateral channels cut in the spur between the Washburn and Stainburn valleys during the regression of the Wharfedale ice, the intake of the lowest, Thrispin Beck, being conspicuous. At Leathley the richly fossiliferous E, shales beside the Washburn opposite Fishpool yielded abundant fossils including Eumorphoceras bisulcatum, Crauenoceras of cotolingense group, N eodimorphoceras hawkinsi and Chaenocardiola footii. The horizon is believed to be between the Almscliff and Scargill Grits. Higher up the river the bottom deposits of the "Washburn Lake," consisting of banded clays, silts and sands, were seen. A short run to Otley preceded the ascent of the Chevin to the Kinderscout Grit capping the summit (PI. 23, A). While poor visibility cut out distant views it was possible to see southward the outcrops of the Middle Grits, Rough Rock and Lower Coal Measures as far as the outskirts of Leeds and Bradford. After lunch the party spent most of the afternoon hammering the Cayton Gill Beds in Great Dib, immediately below the grit of Caley Crags. The unusual facies consisted of about 20 ft. of mudstone, siltstone and sandstone with 16 inches of very hard limestone near the top. Fossils were exceedingly abundant, especially in the upper mudstone beds, and besides crinoid stems, brachiopods and lamellibranchs, included spines of the sponge Hyalostelia, pygidia and heads of small trilobites, gastropods (Phymatifer d. pugilis) , cephalopods including Stroboceras and Coelonautilus, fragments of Reticuloceras and Homoceras d. striolatum, rare corals and bryozoa." The trilobites are the first I The structure is that of half an anticline, faulted up on both sides and pitching in the direction of the dip of the surrounding Almscliff Grit of Rigton Ridge. 2 Identified by Dr. C. J. Stubblefield.
372
SUMMER FIELD
MEETI~G-HARROGATE DISTRICT.
recorded Brachymetopus from British Upper Carboniferous strata and the highest known from a British surface exposure. r The party returned to the bus at Otley and proceeded up the Washburn Valley to Fewston where, through the courtesy of Alderman Lt.-Col. E. J. Clarke, the members of the Association were entertained to tea by the Leeds Corporation. Mr. Shortreed, Leeds Waterworks manager, welcomed the party and afterwards Mr. T. Eastwood expressed the thanks of the Association to Mr. Shortreed and the Leeds Corporation for their kind permission in allowing the various sections in the Washburn area to be visited. As this was the last occasion on which the party would be together, Mr. Ellis and Mr. G. B. Alexander voiced the thanks of the party to the various directors, and in reply Dr. Hudson expressed the dclight of the leaders in being privileged to lead such a field meeting as this and emphasized the great obligation he was under to Mr. Wilfrid Edwards of the Geological Survey who had not only led many of the excursions but had undertaken a great deal of the secretarial work. Then the party proceeded to Fewston Bents Quarry, reserving for the last quarry of the meeting the most fossiliferous exposure in Yorkshire of the Cayton Gill Beds and after vigorous collecting a move was made to examine the John 0' Gaunts overflow channel, which at a stage near the maximum of the last Wharfedale glacier took the water from "Lake Washburn" through a deep trench of characteristic shape intothe Oak Beck Valley. The return to Harrogate thus concluded a most enjoyable field meeting favoured throughout by fine weather and an enthusiastic party. The authors record their thanks to Mr. T. Eastwood and Mr. E. S. Pinfold for the photographs reproduced on PI. 25, to Professor Gilligan for permission to reproduce the photographs, by the late Mr. G. Bingley, reproduced on PIs. 22 and 24 and to the Controller of H.M. Stationery Office for permission to reproduce those on PI. 23. W.E., RG.S.H.
I The neighbouring Eccup Dam trench yielded trilobites from an horizon believed to be: in the lowest parting in the Kindersccut Grit. The highest record is from the Cefn Coed sinking (Middle Coal Measures) in South Wales.
SUMMER TO
FIELD MEETING, 24th JULY 2nd AUGUST, 1938.
THE HARROGATE DISTRICT.
Report by the Directors: R. G. S. HuDSOX, D.Se., WILFRID EDWARDS, M.A., L. H. TONKS, M.Sc., and H. C. VERSEY, D.Se. meeting of the Association was primarily to study the 1 HISrelation and variation in the sedimentation of the Millstone Grit and Carboniferous Limestone, the various features of the Pennine Foothills due to the Vale of York Glaciation, and the Permian succession in Yorkshire. The headquarters of the meeting were at Harrogate. Members of the Yorkshire Geological Society and the Leeds Geological Association were invited to the meeting, and altogether forty-one members and friends attended. In the absence of Professor Hawkins, Mr. \V. D. Ellis, C.M.G., M.A., acted as President throughout the meeting. Sunday, 24th July. The Succession and Structure of the Harrogate Anticline. The party proceeded by train to Pannal, on the south-east side of the Harrogate Anticline, and walking west-north-west towards the axis, under the guidance of Mr. Edwards and Dr. Hudson, traversed a descending sequence of the lower beds of the Millstone Grits. The linear ridges made by the outcrops of the inclined grit beds give the area a distinctive topography, but later in the day it was observed that such features were entirely absent from the plateau tops owing to the filling of depressions by boulder clay. After examining sections in the Harrogate Grits members collected from an exposure in Upper Bowland Shale in Crimple Beck, 600 yards W.N.W. of Hill Top Hall. Fossils indicated an horizon in the C. malhamense sub-zone (E,). This is the first record of the sub-zone in the Harrogate area, and as such confirms the correlation of these shales with the Bowland Shales [21]. * Howe Quarry, Beckwith, afforded an excellent section of the Harrogate Roadstones and of the top of the underlying Middle Bowland Shales. Members of the party were very interested in the lithology of the Roadstones and some discussion took place as to the origin of the chert which forms the chief cement of the rock and which binds together the calcareous crinoid ossic1es. Dr. Hudson's view that the chert was of primary deposition [21} met with considerable dissent. Mr. Edwards mentioned an unpublished record by A. H. Green of moulds of Spirifer, Productus, and" a thing like Sacca• Numbers in Clarendon type refer to the references given in the preceding paper,
U
The
Geology of the Country around Harrogate," P. 329 et seq. PROC. GEOL.
Assoc.,
VOL.
XLIX.,
PART
4,
1938.
22
354
W. EDWARDS AND R. G. S. HCDSON,
mina carteri " from beds close under the Roadstones. The Middle Bowland Shales are almost entirely unexposed and have yielded no fossils, but the Harlow Hill Sandstone, the inferred equivalent of the Nettleber Sandstone of the Skipton Anticline [26) was well seen at Howgill Quarries. The probable position of an inlier of Lower Bowland Shale along the axis of the anticline is indicated by features here and to the north-east. A walk across the axis past the Sulphur Springs in the Harrogate Grits at Harlow Carr led to a beck cut into those grits; dips N.N.E. at angles up to 80° were seen. The magnificent ridge of Birk Crag displayed sections in the coarse Almscliff Grit at the top of the Harrogate Grits, and provided an extensive view of the country to the north, where the sharp outcrop of the Scargill Grit, and the less distinct feature made by the Lower Follifoot Ridge Grit, indicated the dying out of the steep folding of the anticline. The depth and youthful appearance of Oak Beck at the foot of Birk Crag is attributed by Kendall to glacial overflow through the John 0' Gaunt channel farther west. After tea the more active members of the party walked to Oakdale where, at Oakdale Farm, the Scargill Grit dipping N.W. at about 60° was examined. A traverse was then made across the Follifoot Grits and Cayton Gill Beds to Grange Brickworks where, by the courtesy of the Allied Brick and Tile Works, Limited, an examination was made of the shales in the quarry. These shales occur above the lowest member of the Brimham Grits. The floor of the quarry consists of a siltstone from which the shale has been stripped; members were very interested in the top surface of this siltstone which shows an almost perfect ripple-marked surface. Limy ironstone nodules had been collected into a heap in the quarry and in these numerous examples of Productus carbonarius were found. Other fossils included various gastropods and lamellibranchs. In the shales numerous examples of Lingula, so perfectly preserved that the colour banding is still visible, were found. A few feet above the base of these shales a marine band containing goniatites was collected from. It contained H omoceras striolatum and numerous Dimorphoceras and fixed the age of the shales as belonging to the Reticuloceras reticulatum zone (R 1 ) . W.E., RG.S.H. Monday, 25th July. The Middle Yoredale Inliers of Upper Nidderdale. The main purpose of the day's excursion was to visit, under the guidance of Mr. L. H. Tonks, the limestone inliers of Lofthouse and Limley which occur beneath the Millstone Grit and to recognize by their characteristic fossils that these limestones are the equivalent of the Middle Limestone of Wensleydale,
SU~DIER FIELD MEETING-HARROGATE DISTRICT.
355
thus proving, since the Main Limestone and its associated beds are absent, the unconformity of the Millstone Grit on the Yoredale Series. During the outward journey to Lofthouse by Pately Bridge Mr. Edwards recounted the salient features of the Nidderdale glaciation, as described by Kendall, Raistrick and Tillotson [57, 64, 66, 69J. While the distribution of boulder clay on the surrounding hills indicates a former invasion of the whole region by icc, during the latest (York-Escrick) stage of the glacial period Nidderdale was occupied by a local glacier, which, although feeble compared with the ice-streams in other dales, left obvious traces of its occupation in the form of valley bottom moraines and gravels, marginal deposits and lateral drainage channels. It made but slight modification to the topography. During the day attention was drawn to the hummocky moraines between Ramsgill and Glasshouses, the flat above Gouthwaite Reservoir attributed to silting up of a lake blocked by the moraines at Wath, the jumble of fragmentary terraces along the valley bottom showing features of valley trains laid down and dissected during successive periods of ice shrinkage, and the paucity of drift and the absence of well marked corries in the upper part of the Dale. Some difficulty was shown in accepting the competence of a glacier springing from such restricted gathering grounds to move several miles down the gentle gradient of the valley and to pile moraine up to nearly 1,000 ft. above a.D. on the hill slopes at Pateley Bridge, especially since the maximum recorded height of drift near the Dale top is only TAoO ft. a.D. [69, p. 217]. Invasion by an extraneous ice-lobe is discounted, however, by the absence of erratics from outside the dale. While lateral moraines were nowhere obvious during the visit there were seen at many points in the upper dale rude terraces high up on the valley sides showing apparent ice-contact slopes. Their resemblance to kame terraces' was pointed out. The motor coaches were left at Lofthouse and the party proceeded to Lofthouse Bridge. Here Mr. Tonks gave an account of the Middle Yoredales succession as it is exposed at the various inliers of Lofthouse, Limley and Angram [35]. Then a visit was paid to the exposure of Middle Limestone in the Nidd underneath Lofthouse Bridge. The limestone here is the Cockleshell Limestone, the middle division of the Middle Limestone. Various fossils were collected, including good specimens of Chaetetes and Palaeosmilia regia. This locality, 300 yards north of Lofthouse Station, is the type locality for this latter fossil. It was from here that it was first collected by Phillips.". I
Gravelly deposits formed on valley sides against the edges of stagnant ice.
See Salisbury
R. D', The Glacial Geology of New Jersey, Geol. Sura .. N.}., 1902, 121.
Phillips, J. r836. Illustrations of the Geology of Yorkshire. Limestone District, p. 201. PI. II, figs. 25 and 26. 2
PI. II. The Mountain
356
R.
G. S. HUDSO:;
A~D
W. EDWARDS,
The party was then conducted up the bed of the Nidd and Mr. Tonks pointed out the unconformable junction of the Middle Limestone with the overlying Basement (Grassington) Grit. The Millstone Grit succession was well seen on the western side of the valley where, above the Grassington Grit, there was a thick succession of shales capped by the Red Scar Grit, here occurring in two leaves. Old workings in the Woogill Coal which occurs between the two leaves of this grit were seen. It was noted that the thickness of shale on the side of the valley was marked by typical landslip topography, well seen at Puddle House. After lunch the party crossed the small inlier of limestone at Thorpe to the main Limley inlier, and at Goyden Pot the Cockleshell Limestone was again well exposed. Many of the members interested in this underground watercourse of the Nidd attempted a descent of the pothole. Lack of light, however, prevented them from going very far. The limestone of the Limley inlier is folded into a shallow anticline and so, proceeding north, the party worked down the succession from the Cockleshell Limestone to the Single Post Limestone, the lowest member of the Middle Limestone. Here. about 135 yards S.W. of Manchester Holes, a good section in a low cliff overhanging the river exposes limestone from which the members collected excellent specimens of Orionastraea garwoodi, a fossil characteristic of this horizon. After a brief visit to Manchester Holes Mr. Tonks conducted the party to the old railway cutting, where the Cockleshell Limestone was seen with numerous specimens of Gigantella gigantea, many of which were collected by the more enthusiastic members of the party. After tea at Middlesmoor a visit was paid to How Stean Beck where, in the upper reaches of the Beck, there is a good exposure of the Scar Limestone, the uppermost division of the Middle Limestone. The top posts of this limestone contained abundant nodules of A phralysia, calcareous algre which are common on the upper surface of many of the Yoredale Limestones. Above the Scar Limestone there is exposed a thick section of shale The shale contains underlying the Lower Five Yards Limestone. the usual Zaphrentis fauna with abundant Zaphreniis, Fenestella, Rhipidomella, Schizophoria and abundant small spinose productids. The deep gorge of How Stean Beck (Pi. 22, A) cut by solution in the Middle Limestone was visited and then members rejoined the coaches at Lorthouse, On the return journey hammers were put to a coarse terrace deposit, showing the rude, ungraded bedding of valley train material, at Riverside, Pateley Bridge. The gravel was associated with, and apparently banked against, banded silt and loam. RG.S.H., W.E.
tV
Iv Photo: G. Bingley.
Pholo: G. Rin:zley.
,\.-How
STEAK, l'PPER C\IDDERDALE.
B.-J ACKD.\\\'
c\ICK, TROLlERS GILL, .\PPLETREEWICK.
[To 11c,] p. 35(1.
SUMMER FIELD :MEETING-HARROGATE DISTRICT.
357
Tuesday, 26th July. The Millstone Grit Succession of Upper Nidderdale. By kind permission of the Bradford Corporation the day's meeting was devoted to the examination, under the guidance of Mr. L. H. Tonks, of that area of Upper Nidderdale now partially occupied by the Angram and Scarhouse reservoirs. Starting near Scar Village, Mr. Tonks took the party into the bed of the Nidd where sections showed the Millstone Grit resting unconformably on beds above the Middle Limestone. Then the tips from the excavation of the Scarhouse Reservoir were examined and on them numerous examples of a bed of grit with phosphatic nodules were found. This, Mr. Tonks explained, was the basement bed of the grit where it rested unconformably on the Middle Yoredales. From the hillside Mr. Tonks pointed out the features made by the various beds of the Millstone Grit [35, p. 247] and gave a general comparison of the grit succession with that of Harrogate. The party then climbed the hillside and at Tops Gill, 880 yards E.N.E. of Lodge Farm, an exposure of the Colsterdale Limestone was examined. [35, p. 250.] The limestone, about 6in. thick, was here very much decalcified and well deserved the name given to it by the old surveyors of " gingerbread limestone." Vigorous collecting by the party resulted in a complete fauna being obtained. In addition to Cravenoceras nitidum, Cravenoceras sp., A nihracoceras glabrum, Dimophoceras and various lamellibranchs, several examples of Eumorphoceras bisulcatum. were obtained. This last form, previously unrecorded from this horizon, solves one of the difficulties of the correlation of the Colsterdale Limestone with the beds further south. [35, p. 252.] A brisk walk took the party to the Angram Reservoir, and from there a rather perilous walk along the scarp of the Lower Five Yards Limestone enabled the party to reach a good section in that limestone, and from it the typical fauna was obtained. Perhaps the most notable find was a bed rich in a mutation of Zaphrentis enniskilleni. Then a shale section between the Lower and Upper Five Yards Limestones was examined. It was, however, disappointingly poor in fossils. Here, however, the Millstone Grit unconformity could be demonstrated since the Upper Five Yards Limestone, present in this section below the Millstone Grit, was, on the previous day's excursion, shown to be absent beneath the Millstone Grit at Lofthouse and Limley. The party then returned to the motor coaches at Angram, and after tea at Lofthouse made an early return to Harrogate. RG.S.H.
35 8
R. G. S. HCDSOX AXD
,Y.
EDWi\RDS,
Wednesday, 27th July. The Millstone Grit of the Simonseat Anticline and the Lower Carboniferous of the Greenhow Inliers, The motor coach took the party across Knaresborough Forest to Blubberhouses and from there northwards along the valley of the Upper Washburn to Hoodstorth. Here Dr. Hudson pointed out the features of the Simonseat Anticline and detailed the Millstone Grit succession from the Grassington Grits exposed on the crest of the anticline at Simonseat, to the Brimham Grits exposed in the troughs of the neighbouring synclines on Redlish and Whit Moors. He emphasized the importance of the area since it formed a link between the Millstone Grit succession of Upper Nidderdale on the Askrigg Massif and that of Harrogate in the Craven Basin. The first exposure to be examined was at Carlhow Stoop where the Cayton Gill Shell Bed was collected from. Next the area around Hoodstorth Bridge was visited by the permission of the Corporation of Leeds. Here the Cayton Gill Shell Bed and Siltstones and the beds below and above are well exposed. Many fossils were collected from these beds and great interest was shown in the peculiar sedimentation. It was suggested that these beds were the topset beds of a Millstone Grit delta. The party then walked along the Appletreewick road by Hey Slack, traversing the Cayton Gill and Follifoot Grit succession, to Foulgate Bank formed by the scarp of the Red Scar Grit. At the ford at Harding Wife Shaw this grit was seen again, repeated by a strike fault. A brisk walk then took the party across Pockstones Moor. where, at Little Pockstones, the Upper Grassington Grit forms a strong feature. From here Dr. Hudson pointed out the structure of the anticline showing that Little Pockstones, on the core of the anticline, was flanked on both sides by the scarps of the Red Scar Grit and succeeding beds. He also demonstrated the steep pitch of the anticline to the east and pointed out that on the crest of the anticline to the west the Lower Grassington Grit was exposed at Simons Seat where, above 1,550 ft., there were potholes communicating with the limestone below [8]. From here the moorland of tussocky grass was crossed with some difficulty and the party arrived at Birk Gill on the northern flank of the anticline, where an exposure in the shales above the Red Scar Grit contained a thin limestone with Craoenoceras nitidum and Eumorphoceras bisulcatum. There was no doubt that this limestone from its fauna and lithology was the equivalent of the Colsterdale Limestone seen on the previous day in Upper Nidderdale. It is, therefore, an important link in the correlation of the two areas.
SUMMER FIELD MEETING-HARROGATE DlSTRICT.
359
From here, in spite of sprained ankles and the desire for lunch, way was made through the thick bracken along the banks of the Washburn to Nar Hill, where there was well exposed a good example of one of the strong E.-W. faults parallel to the North Craven fault. The fault face and the fault breccia were well seen in section and it was agreed that the fault was a reversed fault thrusting the Red Scar Grit over the Rowan Tree Grit, a grit higher in the sequence. After lunch, Redlish Beck, in which there is a good section from the Lower Follifoot Grit to Cayton Gill Beds, was visited. The interest of this section lay in the exposure of shale, between the Follifoot Grits, containing a marine band with Homoceras beyrichianum, thus dating for the first time these beds as belong~ng to the H omoceras zone (H) of the Millstone Grit sueceSSIOn. Rather weary the party then rejoined the bus and proceeded northwards along Blackgate to the inliers of Carboniferous Limestone along the Greenhow anticline. Lack of time prevented a visit to the Great Scar Limestone of Duckstreet Quarry. Near Coldstones Quarry Dr. Hudson pointed out the structure of the area, emphasizing the fact that in the various inliers exposed beneath the unconformable Millstone Grit the limestone was of various ages [16 and 7]. At Coldstones Quarry, from limestone of D, age, members made an extensive collection of the corals so abundant in this quarry. Lonsdaleia floriformis, Dibunophyllum, Aulophyllum, Palceosmilia regia and numerous Lithostrotions were collected and great interest was shown in the band of algal nodules exposed near the top of the section. After a brief look at the Simonstone Limestone of Toftgate the coach made the difficult descent to Pateley Bridge. This steep descent into Nidderdale at Bewerly was coincident with a spectacular change in glacial topography. Morainic mounds, conspicuous by their absence from the Greenhow area, suddenly appeared in profusion below 1,000 ft. a.D., marking with precision the southern limit of deposition of the Nidderdale glacier. Some indication of lateral drainage was seen at the upper edge of the moraine belt, and lower down the hill, at about 700 ft. a.D., a characteristic lateral channel, cut partly in moraine, was visible from the road. Returning to Harrogate, members of the Field Meeting were received by the Mayor and Mayoress of Harrogate and entertained to tea by the Harrogate Corporation. After tea Mr. Woodmansey, the Borough Analyst, gave a brief talk to the members on the Harrogate wells and then conducted the party into the Valley Gardens, showing them the sites of the various springs. RG.S.H., W.E.
w.
EDWARDS AND R. G. S. HUDSON,
Thursday, 28th July. The Coal Measures South of Leeds. A start was made at 9 a.m. to visit the Coal Measures of the Leeds-Normanton area. Between Harrogate and Leeds the coach traversed the full succession of Millstone Grits, and the main features of the area were pointed out, notably the ridge of the Almscliff Grit along the south-east flank of the Harrogate Anticline from Pannal to Great Alms Cliff, the wide expanse of Sabden Shale around Weeton and the easterly swing of the Follifoot Ridge Grits under the influence of the Wharfe Anticline, the east-west scarps of Follifoot Ridge Grits, Kinderscout and Middle Grits south of the river Wharfe, and finally the ridge of the Rough Rock as the Coal Measures are approached in the northern purlieus of Leeds. At Hawksworth Wood Quarries, Horsforth, the courtesy of Messrs. B. Whitaker & Sons Ltd. enabled the party to examine an extensive section of Rough Rock and overlying Coal Measures. The massive grits of the Rough Rock are parted from the fireclay of the Pot Clay Coal by several feet of variable mudstone, siltstone and uncemented sand rock. The fireclay itself is surmounted by barely an inch of coal, and the succeeding dark mudstones of the Coal Measures contain marine fossils including Gastrioceras subcrenatum, nautiloids, Lingula mytiloides and other brachiopods, lamellibranchs, gastropods and fish scales, scattered through several feet of measures and representing the well-known Pot Clay Marine Band. Boulder Clay occurs at the top of the section and yields sand-blasted stones at the surface. From Horsforth the route lay through Leeds to Thorp-on-theHill, near Robin Hood, where Messrs. George Armitage and Sons Ltd. kindly allowed an examination of the classic section in their brick pit (PI. 23, B). The Haigh Moor coals, with overlying richly fossiliferous measures of an abnormal type are exposed in an immense excavation, and have yielded a large fauna and flora. After examining the quarries in the Thornhill Rock, the members devoted some time to a heap of ironstone nodules from which they collected various plants. Dr. Hudson then pointed out the lie of the beds in the Coal Measures quarry, and explained the evidence for the fault to the north of it. A start was made in the examination of a succession in the beds below the Lower Haigh Moor Coal and from there numerous examples of N europteris heterophylla were obtained. A good section in the Upper Haigh Moor Coal and its underlying fireclay was then examined, and some discussion took place on the origin of the cleat which was well shown in this section. Old mine workings in the Upper Haigh Moor Coal were well exposed,
PROC. GEOL.
Assoc.,
VOL.
XLIX. (1938).
PLATE
23.
A.-\VHARFEDALE FHO:lI OTLEY CHEVr,.,;.
2\IEASVRES, EOBl!' HOOD QVARRY, LEEDS.
[To face p. 360 .
SUMMER FIELD MEETING-HARROGATE DISTRICT.
361
and it was noticed that there had been a settling of the beds above these old workings resulting in small downward folds of the thin coal above. Above the Upper Haigh Moor Coal further ironstone nodules were broken and yielded good specimens of N europteris gigantea and Lepidophloios. A visit was then paid to the Carbonicola beds [36J and many examples of Carbonicola aquilina and Anthracomya modiolaris were obtained. In the sandstone at the top of the succession a fossil tree trunk was noticed standing upright with its skin of bright coal still in place. Proceeding from Robin Hood through Whitwood to Altofts, the party saw abundant evidence of colliery activity. It was explained that the West Yorkshire Coalfield comprises over 4,000 ft. of measures, lying nearly fiat but considerably faulted, with many thin seams and some 10 to IS workable seams spread over a vertical distance of some 2,600 ft. At West Riding and Silkstone Colliery the party were met and welcomed by Mr. O. H. Jones, Secretary and Director of Messrs. Pope & Pearson Ltd., by Mr. J. E. Waring, Manager, and Mr. N. E. England, Surveyor. Before descending the pit they inspected a scale model, constructed by Mr. England, showing the geological structure of the area. Of the 9 to 10 seams worked at the colliery three were seen during a lengthy tour of the workings. The Warren House Coal was first inspected in order to see a seam with normal roof, being worked longwall with coal cutters. The Stanley Main workings were then entered in order to see roof shales with fossil plants and "pot holes" (erect internal casts of large lycopod stems cased with vitrain representing the original bark.) Chief interest centred in the "rock faults" exposed in roads close to the edge of a washout area in the Haigh Moor Coal. A prominent feature of the sections seen was the irregular interleaving of sandstone with coal in the seam and with mudstone in the roof: such phenomena are common near washout areas where sandstone forms the washout filling, but as yet lack adequate explanation. Equally prominent were the true " rock faults," irregular masses of sandstone, mudstone and coal, and of the interleavings mentioned, jumbled together in gigantic breccias. The junctions of dissimilar fragments in the breccias usually showed angular and slickensided surfaces; occasionally sandstone showed smoothly folded and creased surfaces against which the weaker mudstone and coal was crushed. One large sandstone mass had been intensely folded before itself becoming part of the breccia. The folding and brecciation are attributed [11, and Fearnsides, W. G., Trans. Inst. Min. Eng., L, 1916, p. S83J to stresses during compaction of the washout filling (Haigh Moor Rock)
W. EDWARDS A::\D R. G. S . H UD SO::\,
a nd of the underlying sediments, lateral squeezing being at a m aximum on the sides of the washouts. Duplicat ion and even triplication of seam by lateral thrust ing ar e occasional result s of such movemen t s, and the charac teristic example figured from the present pit by Professor Fearnsides was still part ly visible. The fact that br ecciation had preceded the cleating of th e coal was noted . Whil e the party were undcrgound th e ladi es were shown the surface plant and t ak en down t o th e Beeston seam at 1,487 ft. to see the layout of the pit bottom and the pit ponies. Members were enterta ined t o t ea by the Company , and ga ve a hearty vot e of th anks t o ':.\Ir. J ones and other members of t he st aff for their kindness. The return journey was mad e with out stop, a projected visit to the new Mount Pleasant sinking of Messrs. T . and R. 'V. Bower Ltd., having to be abandoned owing to shortage of time. W.E., R.G .S.H . Friday, 29th July. The Millstone Grit North-west of Harrogate and the Glacial Features of the Fountains District. Th e party left the motor-coach at Little Alms Cliff . and from th is view-point were shown the t opographic features of the south-western part of the H arrogate Anticline. H ere the axial zone is occupied by a broad out crop of the lower part of the H arrogate Grits, with the Almscliff Grit forming a flanking rid ge on either side. The drift of this are a is a featureless spread of boulder clay , locally thick on the hilltops and abs ent from the v alleys; it is at least as old as the early Main Dales Glaciation, and may be Older Drift. To the north of Little Alms Cliff Dr. Huclson pointed out the various scarps due to t he succession of Scargill Grit, Follifo ot Grits, Cayton Gill Beds and Brimham Grits and emphasized t he folded nature of th e Knare sborough F orest country to the north, pointing out th e lie of the Beam sley and Simon seat Anticline. To the far north the highlan ds of the Askrigg massif could be just seen. To the north-east over H arrogate there was a good view of the Vale of York and the Cleveland Hill s. By permission of lVIr. West, the party were then taken across H averah Park, the catchment ar ea of Harrogate Reservoirs. South of Scargill Reservoir a good section in the shales above the Scargill Grit was seen. Decalcified limestone in these shales contained good specimens of Crauenoceras nitidum and Eumorphoceras bisulcatum, leaving no doubt in the minds of the party that this bed was the equivalent of the Colste rdale Limestone of Up per Nidderdale and t he Birk gill Lime stone of the Simonseat Anticline. It wa s emphasized that it was only by mean s of such
SliMMER FIELD :MEETING-HARROGATE DISTRICT.
363
faunal bands, lithologically unimportant, that the correlation of these big thicknesses of grits could be established. Further along Scargill Beck a section between the Lower and Upper Follifoot Grits was visited, and here a bed of limy ironstone contained good examples of Dimorphoceras and Posidoniella laevis. Although an unsuccessful search was made for H omoceras beyrichianuni which should occur near this level, a band of nodules containing abundant "Yucula was discovered. Rejoining the bus at Penny Pot Lane the party rapidly traversed the featureless drift-covered country of that area and arrived at the section in the shales near Victoria House, Hampsthwaite. These shales, whose exact stratigraphical position has not yet been determined, contained bullions with Crauenoceras edalense and Crauenoceras subplicatum, for which latter form this section is the type locality [3]. Good examples of these, together with Eumorphoceras bisulcatum and Anthracoceras sp. were found. After lunch in Hampsthwaite and a visit to the old church the party crossed the Nidd to the famous quarry in the Cayton Gill beds near Clint. In the shell bed near the top of the exposed succession good examples of Productus carbonarius, Derbyia gigantea and Schizophoria hudsoni were collected. After a successful rat hunt in Clints Ouarrv the bus was rejoined and took the road past Brimhar'; Rocks, the finest group of weathered stacks in the district. General opinion favoured Pleistocene wind action as the originator of the present forms of these rocks, and it was pointed out that this action was probably later than the early part of the Main Dales Glaciation, since the ice at that period probably covered the interstream areas on the flanks of the Pennines. It was also suggested that since these and other groups of stacks throughout the Pennines tended to occur only on hilltops, they were relics of more extensive areas of weathered rock which had been removed from sloping areas during the last glacial phase, either by snow-field creep or by solifluxion (PI. 24, B). Proceeding across Sawley Moor, the party saw the Eavestone channel on the left and the conspicuous intake of the Picking Gill channel on the right, two overflows related to the highest defined stand of the Vale of York glacier during the YorkEscrick Stage. Farther east and at a lower level, the next ice-front stand, as defined by Kendall and Wroot, was seen to be marked by a massive belt of moraines and kames fringed with the sequence of large overflows at Sun Wood, Spa Gill and The Dene, in line with the Laver diversion to the north. A quarry at Clip'd Thorn showed a face of gravelly moraine which yielded, besides the abundant Carboniferous erratics, igneous rocks comparable
w,
EDWARDS AND R. G. S. HUDSON,
with Cheviot porphyrites, Whin Sill dolerite and Lake District volcanics. Shap Granite is recorded here by Raistrick. Complex drainage phenomena were seen in this region, where, according to Raistrick, the northern (Teesdale) ice has swung westward on to an area being cleared of Pennine ice, with consequent adjustment in lateral drainage. A halt was made at Fountains Abbey for tea and to see the ruins. Here the party were joined by Sir Arthur and Lady Smith Woodward. Then the road was taken past Morker, where the moraine topography was particularly fine, to Haddockstones. An extensive flat was seen to mark the site of the Hebden Beck lake, which received during successive retreat stages the waters from Picking Gill and The Dene, and overflowed through Cayton Gill (Pl. 24, A). A halt was made in Cavton Gill near Dole Bank, where the characteristic features of this great overflow were seen to perfection. The lateral moraine was crossed on the road to Markington, and again approaching Ripley, where the road descended from it on to the gravel flat explained by Kendall and Wroot as the delta of Cayton Gill. A recent road-cutting near Ripley Valley Station gave a section in the river-cut edge of this flat. Gravel with a basal layer of false-bedded sand lay abruptly on a thick series of thin bedded clay, silt and loam, such as might have been deposited here in the glacial lake whose overflow cut the Knaresborough Gorge. The wide valley of the Nidd at this point was contrasted with its channel-like gorge farther east. A short journey took the party back to Harrogate. W.E., RG.S.H. Saturday, 30th July. The Great Scar and Reef Limestones of the Burnsall Anticline.
To-day's excursion was devoted to the study of the limestone exposed in the Burnsall Anticline, particular attention being devoted to the passage of the Great Scar Limestone into the Cracoe Reef Limestone and also to the topography and structure of the Reef Knolls. The journey to the Burnsall area was made via Bolton Abbey and Barden Towers. The first stop was made near Intake Plantation, where an extensive view was obtained of the Wharfe Valley from Burnsall to Skyreholme, and here Dr. Hudson pointed out the main features of the area, demonstrating the course of the North Craven Fault and emphasizing that it was in this area that there was a sharp change from basin to massif sedimentation and that the Carboniferous Limestone was here 'Of the marginal facies. In the same way he pointed out that it was in this area that the passage from the Lower Bowland Shales to the Lower Yoredale Series could be proved.
Pnoc. GEOL. Assoc., VOL. XLIX. (1938).
A.-·GLACIAL :\r."RGINAL CHAl-il"EJ..
PLATE 24.
C ·\YTON CILl..
B,-\\'!l';D-ERODED :\IULSTO:"'E GRIT. 131'1:11clAM, ~Tn
[ace p. 3(q·.
SUMMER FIELD l\1EETlNG-H,\RROGATE DISTRICT.
365
The journey was continued to Middle Skyreholme and there Dr. Hudson pointed out the position of the syncline between the Simonseat Anticline and the Skyreholme Anticline and called attention to the valley of Blands Beck occupying the trough of the syncline. The party then proceeded along the valley of Skyreholme Beck, cut through the steeply southwarddipping Basement Grit, to near Percival House, where the junction of the grit and the limestone was demonstrated. Proceeding into Trollers Gill the party examined the limestone, noted its bedded character and its finely fragmental nature and agreed that it was of Great Scar facies. The topography of Trollers Gill was noted as an example of underground solution and collapse and considerable interest was taken in the springs which issued on the floor of the Gill, discussion taking place as to their origin and the reason for such a level of the water table. Next, the party worked its way along Jackdaw Nick (PI. 22, B), an example of the more recent collapse of the roof of an underground water course. Here the overhanging sides of the gorge were readily seen. Returning around Middle Hill the party entered the neighbouring gorge of Gill Beck and proceeded to Gill Head Lead Mine, where good yellow fluorspar and some galena were collected. Most members proceeded some short way into the workings, and here Mr. Eastwood gave a short talk on the method of working. The actual vein worked in this mine was well seen. Then Dr. Hudson discussed the age of the Iimestone and showed that the fossils dated it as belonging to the zone DrHe then took the party to Hell Hole, a pothole exposing the top of the limestone with a band containing Girvanella nodules. The upper part of the gorge of Skyreholme Beck was visited and the northern flank of the anticline well seen. Here the top of the Great Scar Limestone and the base of the Millstone Grit were pointed out and it was seen that between them there could only be a comparatively small thickness of beds. These beds, not well exposed, are intermediate in facies between the Lower Bowland Shales and the Lower Yoredales. The best exposure was seen at New Dam, where the Black Hill Limestone [1] aroused considerable interest as a condensed shelly limestone deposit. From this limestone good examples of Lonsdaleia floriformis, Chaetetes and Lithostrotion were collected proving the limestone to be of D, age, the equivalent of the limestone of Coldstones Quarry seen on a previous excursion. Then moving to the road, the grit of Fancarl Crag was well seen with the Great Scar Limestone exposed at the same level in a quarry behind it. The two exposures are separated by the North Craven Fault. Returning to Appletreewick the party rejoined the coach and proceeded to Badger Lane beyond Burnsall. Here Dr. Hudson pointed out the various knolls of Reef Limestone such as Byra
366
R. G. S. Hl'DSO:'\, W. EDWARDS AND H. C. VERSEY,
Bank, Thorpe Kail and Elbolton (PI. 25, B) and showed how the Bowland Shale rested on the limestone, and that the junction between the shales and the reef limestone was a very sinuous one, wrapping round the knolls. In 'Waterspout Beck Mr. Black demonstrated the Lower Bowland Shale succession and pointed out a limestone boulderbed in the shales. Returning to Badger Beck some discussion took place as to the origin of the isolated mass of limestone exposed in the beck. It was suggested that it was either an immense boulder in the shales, or, better still, a stack of limestone protruding through the shales. Lack of time prevented an examination of the limestone of Thorpe Kail and the party proceeded immediately to Elbolton, where a small quarry on the south-eastern flank yielded an abundant fauna of typical wellpreserved reef fossils. The more active members of the party climbed Elbolton and examined Navvy Noodles Hole, a pothole which, excavated in the latter years of the last century, yielded bones of many vertebrates. The origin of this pot hole at rr25 ft. a.D. on the top of Elbolton is a subject for much discussion. Dr. Hudson pointed out that it may have arisen when the greater part of Elbolton was covered with shale, forming a gathering ground for the water which made its escape through the limestone thus forming the pothole. The other members of the party made their way around Elbolton and took great interest in the topography of Stebden Knoll (PI. 25, A). Here the outcrop of shale completely surrounding the Knoll could be inferred from the distribution of rushy vegetation of the shale and the short grass of the limestone. It was seen that the Millstone Grit of Rylstone Fells if continued would rest directly on Stebden Knoll completely overlapping the Bowland Shales. At Linton Dr. and Mrs. Raistrick kindly entertained the party to tea and later Mr. Eastwood voiced the thanks of the party for their hospitality. Since it was now very late the party returned straight to Harrogate omitting the visit to both The Strid and Bolton Abbey. . RG.S.H. Sunday, 31st July. Knaresborough and Tadcaster. Travelling by road to Knaresborough, the party reached the Castle, perched above the winding limestone gorge occupied by the Nidd. Upstream there is about three miles of gorge, cut mainly in Millstone Grits and more truly an overflow channel, since at Knaresborough the glacial water has evidently only accommodated itself to an existing valley system, traces of which remain in the asymmetry of the gorge and in the mature valley of Holbeck, which runs into the Nidd from the south.
I'ROC. GEOL.
Assoc.,
VOL.
. \. --STEIlDEJ-;
XLIX. (1938) .
PLATE
25.
I"'~OLL, "'EAR CRACOE.
13,-ELBOLTON KNOLL, NEAR CRACOE.
Photo: F. S. Pintold, C.-GNCOXFOR\IABLE ]UKCTIO-r-: OF ~IAGKESIA~ LL',IESTOKE AND :\IILLSTOXE
GRIT,
KKARESBOROUGH.
Se\DlER FIELD ~lEETING-HARROGATE DIST1UCT.
J67
An examination was then made of the very fine section exposed on the north side of the gorge. Here the stained Brimham Grit with a fossil tree is truncated by the unconformable base of the Lower Magnesian Limestone (PI. 25, C). Attention was drawn to the sandy nature of these lower beds and to the presence of local re-crystallisation. A detour was made to the Dropping 'Well, where an extensive tufa screen composed largely of calcium sulphate is deposited by a spring emanating from the limestone. After some of the party had performed the usual ritual at the Wishing Well the journey was continued down Abbey Walk where rough concretionary structures and magnesium sulphate efflorescences were seen. Near Abbey House the limestone was seen bedded over elevations of the underlying grit. Near Grimbald Crag, after examining the nature of the pebbles in the Brimham Grit, members again saw the unconformity, its position on the Crag being due, in part, to an eastwest fault. This fault was seen in a neighbouring quarry throwing limestone against the Middle Marl. The pebbly nature of the lowest bed of limestone was taken as pointing to the presence under the quarry of a "knob" of grit. Higher up the limestone shows a wedge-bedding characteristic of the upper beds of the Lower Magnesian Limestone. Below Grimbald Bridge a gravel spread is delta-bedded as if by water issuing from the Knaresborough Gorge, but at Goldsborough Mill there is again a rock-gorge, and from here to Ribston the Nidd hugs the edge of the rising ground to the west, and has cut into the solid rock in places, as if under the influence of a neighbouring ice-edge. There is some evidence of a small marginal lake along this part of its course, for laminated clay overlain by fine, well graded gravel, was seen close to the river at Scaliber. Moraine deposits were not obvious between Knaresborough and Ribston, but appeared at North Deighton east of the large, flat-graded Kirk Deighton channel. At Wetherby the party got a sight of the intake of the Wharfe diversion, and saw the wide, flat-floored valley higher up, where sections have revealed beds of laminated lake-clays. Near Wattle Syke, Collingham, a gravel pit was seen in coarse, kame-like material, forming part of a sharp ridge with a steep side facing north-east and suggesting an ice-contact slope. This ridge is one part of an interrupted line of similar gravels, trending south-eastwards through Linton and Bramham and continued by the gravels seen later in the day near Wingate Hill. Recently observed and not yet mapped in detail, it is in all probability an ice-front deposit of the Vale of York glacier, parallel with and about two miles outside of the line of the Escrick Moraine.
W. EDWARDS AND H. C. VERSEY,
Continuing the journey to Boston Spa, the bus halted at Ingle Bank, where a disused quarry showed terrace gravels of the Wharfe, now under investigation. A sudden change in water level, perhaps the effect of ice-blockage, was suggested by the abrupt upward transition from gravel to loam. This latter material contained masses of angular Head, derived from the hillside above and containing fragments of shelly Upper Magnesian Limestone. Many of these fragments were sand-blasted, and led to a discussion on the close connection between soliftuxion and wind-action as evidenced by the late glacial drifts in Yorkshire. At Wingate Hill above Tadcaster members were indebted to Messrs. Aberford Quarries Ltd. for facilities to examine their gravel pit, now extended into a large excavation. The material worked forms a ridge on the hilltop with a steep northward facing edge, and is a mixture of coarse unsorted gravel, sand, loam and bedded clay, showing much sharp disturbance and having the general appearance of a kame deposit. Permian limestone abounded and tended to form large ice-scratched boulders, Carboniferous sandstone and limestone were common and a few far-travelled erratics were found, including rocks resembling Whin Sill dolerite, Cheviot porphyrite, with quartzite and one piece of mica-schist. A similar section was afterwards seen, through the courtesy of Messrs.]. H. Walker and Co. Ltd., at Stutton Gravel Pit farther down the hill, the gravel and sand showing bedding towards the south with much disturbance amounting in places to overfolding. A short walk led to Towton, where tea was enjoyed. Afterwards the gravel pit at the south end of the village showed a characteristic section in the 100 ft. Strand Line gravels. Coarse boulder beds and gravels, consisting of local Magnesian Limestone were seen resting on a smooth surface sloping gently eastwards, while evidence formerly visible showed that in that direction they pass laterally into limestone sands. Later a section in the same beach gravels at Garnet Lane, Tadcaster, showed coarse shingle with underlying sand resting on a sloping rock surface blanketed with Head. The return journey was made through Plumpton, where the Brimham Grit is weathered into erosion stacks similar to those at Brimham Rocks. The propinquity of the overlying Magnesian Limestone caused some speculation as to the possible prePermian age of the stacks. W.E., H.C.V. Monday, 1st August. Ripon and Masham. The party left headquarters by bus for Wormald Green. Here the Magnesian Limestone is worked in a large quarry which shows
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the upper beds of the Lower Limestone. Satisfactory discrimination between the Lower and Upper limestones is not possible in this area, but in the quarry two feet of a grey marl is exposed. Some discussion ensued as to the possibility of this being a residue from limestone solution, but the limestone itself shows the cellular structure due to solution of ooliths which is common in South Yorkshire under the Middle Marls. Extensive stalagmitic deposits were also seen in joints and cavities in the south of the quarry. Overlying the limestone was boulder clay with a profusion of scratched Carboniferous Limestone blocks, and appearing to represent true ground-moraine. The journey was then continued to Ripon Station. On the Thirsk road, just north of the station, an old quarry in Bunter Sandstone was examined and proved to reveal alternations of red and yellow sandstone of medium grade with some indications of wind deposition. The colour variation was attributed to variation in water level during deposition. Certain circular depressions were then seen in fields by the railway. These are attributed to solution of gypsum in the underlying Upper Marls, and in one of the pits the Bunter was seen. It was pointed out that although many of these came into existence some sixty years ago, the area is apparently stable at present. Continuing on the Masham road, the party left the bus at North Lees and proceeded by field paths to the riverside, where the Upper Marls are well exposed. The marls owe their presence here to a pair of faults crossing the Vale of York. Near the base of the section about IS ft. of massive gypsum is exposed and is regarded as the equivalent of the well-known anhydrite bed revealed in borings. Above it the marls are extensively contorted with beds of fine satiny gypsum. In view of the uniform orientation of the gypsum crystals, it was felt that the formation of the minerals must be a secondary phenomenon associated with the contortion while still later deposition is shown by thin veins occupying faults and showing a different orientation. Rejoining the bus the party saw the site of a Roman defended house at Castle Dikes and at West Tanfield wide gravel terraces which lie at three levels and which are related by Raistrick to recessional moraines higher up the Ure valley. During an interval here for lunch members visited the Marmion antiquities, after which the journey continued via the Bronze Age camps at Thornborough to Well Scar limestone quarry. Here an unusual facies of the Lower Magnesian Limestone was seen yielding Producius horridus in its lowest beds. The rock exposed is grey in colour and very reminiscent of compact Carboniferous limestone. Concretionary layers are frequent, but fossils in these are rare. It was pointed out that the Magnesian Limestone in this area is thickening due to the presence of these Pnoc,
GEOL.
Assoc.,
VOL.
XLIX.,
PART
4, 1938.
23
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H. C. VERSEY, \V. EDWARDS AND R. G. S. HUDSON,
lower beds which are possibly overlapped farther south. From the top of the quarry opportunity was taken to point out the continuation across the Vale of York of the trough faults mentioned above into the Coxwold Gap. Here also, removal of the overlying boulder clay has exposed a wide stretch of glaciated pavement, with strise trending a few degrees east of south. After passing Masham members were met by Major Douglas Collins and conducted to view points in the grounds of Hack Fall to see the magnificent gorge of the River Ure, a lateral channel cut in rock during a late stage of retreat of the Wensleydale glacier. Major Collins exhibited specimens of tufa deposited by a spring on the hillside in a manner analogous to that of the Dropping Well, Knaresborough, and received a vote of thanks from the party. Leaving Hackfall the route layover an area of large hummocky hills around Grewelthorpe. A large opening at the east end of the village showed rudely bedded coarse gravel more resembling kame than moraine material, and it is probable that many of the gravelly hills in this area, usually referred to as moraines, will prove on investigation to be kames. The road from Grewelthorpe to Ripon crossed the large dry trench of Thieves Gill, a long marginal valley related to the diversion of the Ure at Hackfall. Tea at Ripon was followed by a journey via Ripley to the large quarries of Messrs. XL Gravels Ltd. at Lingerfield, near Scotton. These showed gravel of glacial outwash type, coated in places with manganese dioxide, and overlain by boulder clay. This superposition might be accounted for in a variety of ways, most easily perhaps by a slight oscillation of the ice-margin. The party returned thence to Harrogate.
RC.V., W.E. Tuesday, 2nd August. The Glaciation and Millstone Grit Succession of the Wharfe Valley. Leaving Harrogate the party took bus to Stonefall Brick Works at Woodlands, where Messrs. Allied Brick and Tile Works permitted examination of the section. The Weeton Shales here contain nodular limestone masses with Cravenoceras and Anthracoceras. A peculiar feature of the section was the uniform downward penetration to about 25 ft. of purple-red staining affecting both mudstone and nodules. This was ascribed to pre-Permian desert conditions, since the Permian lies only half a mile away to the east. A traverse of the rib-like outcrops of the Follifoot Ridge Grits brought the party to Spofforth Haggs Quarry; here a cherty facies of Cayton Gill Beds was seen to be less fossiliferous than that
S1.nr:vIER FIELD MEETI:\G--HA.RROGATE DISTRICT.
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at the eponymous locality. The outcrop was shown to lie in a broad syncline between the Harrogate and Wharfe anticlines, the south-westerly rise of the Follifoot Ridge Grits under the influence of the latter fold being conspicuous. The route led across Follifoot Ridge and the broad depression of the Weeton Shales at Pannal to Great Alms Cliff, which was ascended. Some discussion of the peculiar features of this hill took place, and the opinion was expressed that its development as a huge crag rising high above the subdued outlines of Rigton Ridge lay partly in original structure,' partly in subsequent erosion in which the Pleistocene ice-sheets took part. Shortage of time led to the abandonment of part of the original programme, and the bus continued past Staniston Hill, an isolated kame marking the probable limit of the last Wharfedale glacier, to the bank top above Leathley. The road descending to the village crossed a series of lateral channels cut in the spur between the Washburn and Stainburn valleys during the regression of the Wharfedale ice, the intake of the lowest, Thrispin Beck, being conspicuous. At Leathley the richly fossiliferous E, shales beside the Washburn opposite Fishpool yielded abundant fossils including Eumorphoceras bisulcatum, Crauenoceras of cotolingense group, N eodimorphoceras hawkinsi and Chaenocardiola footii. The horizon is believed to be between the Almscliff and Scargill Grits. Higher up the river the bottom deposits of the "Washburn Lake," consisting of banded clays, silts and sands, were seen. A short run to Otley preceded the ascent of the Chevin to the Kinderscout Grit capping the summit (PI. 23, A). While poor visibility cut out distant views it was possible to see southward the outcrops of the Middle Grits, Rough Rock and Lower Coal Measures as far as the outskirts of Leeds and Bradford. After lunch the party spent most of the afternoon hammering the Cayton Gill Beds in Great Dib, immediately below the grit of Caley Crags. The unusual facies consisted of about 20 ft. of mudstone, siltstone and sandstone with 16 inches of very hard limestone near the top. Fossils were exceedingly abundant, especially in the upper mudstone beds, and besides crinoid stems, brachiopods and lamellibranchs, included spines of the sponge Hyalostelia, pygidia and heads of small trilobites, gastropods (Phymatifer d. pugilis) , cephalopods including Stroboceras and Coelonautilus, fragments of Reticuloceras and Homoceras d. striolatum, rare corals and bryozoa." The trilobites are the first I The structure is that of half an anticline, faulted up on both sides and pitching in the direction of the dip of the surrounding Almscliff Grit of Rigton Ridge. 2 Identified by Dr. C. J. Stubblefield.
372
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MEETI~G-HARROGATE DISTRICT.
recorded Brachymetopus from British Upper Carboniferous strata and the highest known from a British surface exposure. r The party returned to the bus at Otley and proceeded up the Washburn Valley to Fewston where, through the courtesy of Alderman Lt.-Col. E. J. Clarke, the members of the Association were entertained to tea by the Leeds Corporation. Mr. Shortreed, Leeds Waterworks manager, welcomed the party and afterwards Mr. T. Eastwood expressed the thanks of the Association to Mr. Shortreed and the Leeds Corporation for their kind permission in allowing the various sections in the Washburn area to be visited. As this was the last occasion on which the party would be together, Mr. Ellis and Mr. G. B. Alexander voiced the thanks of the party to the various directors, and in reply Dr. Hudson expressed the dclight of the leaders in being privileged to lead such a field meeting as this and emphasized the great obligation he was under to Mr. Wilfrid Edwards of the Geological Survey who had not only led many of the excursions but had undertaken a great deal of the secretarial work. Then the party proceeded to Fewston Bents Quarry, reserving for the last quarry of the meeting the most fossiliferous exposure in Yorkshire of the Cayton Gill Beds and after vigorous collecting a move was made to examine the John 0' Gaunts overflow channel, which at a stage near the maximum of the last Wharfedale glacier took the water from "Lake Washburn" through a deep trench of characteristic shape intothe Oak Beck Valley. The return to Harrogate thus concluded a most enjoyable field meeting favoured throughout by fine weather and an enthusiastic party. The authors record their thanks to Mr. T. Eastwood and Mr. E. S. Pinfold for the photographs reproduced on PI. 25, to Professor Gilligan for permission to reproduce the photographs, by the late Mr. G. Bingley, reproduced on PIs. 22 and 24 and to the Controller of H.M. Stationery Office for permission to reproduce those on PI. 23. W.E., RG.S.H.
I The neighbouring Eccup Dam trench yielded trilobites from an horizon believed to be: in the lowest parting in the Kindersccut Grit. The highest record is from the Cefn Coed sinking (Middle Coal Measures) in South Wales.