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Fluvial sedimentary geology and geochronology of the Holocene Rhine-Meuse delta, The Netherlands
290
Book Reviews /Sedimentary
Postma, A.R. Fortuin and W.A. van Wamel), Archaean and Cenozoic tectonic escape basins in S. Africa (I.G. Stanistreet), Pennsylvanian and Paleocene coal beds in the eastern USA (E.S. Belt), Plio-Pleistocene outer arc basins in Costa Rica (H. van Eynatten, H. Krawinkel and J. Winsemann), Mesozoic-Early Tertiary sedimentary evolution of the Antalya Complex in SW Turkey (A.H.F. Robertson), Plio-Quaternary sedimentation in the eastern Tyrrhenian (A. Argnani and F. Trincardi), and a Late Proterozoic accretionary prism in Central Namibia (P.A. Kukla and I.G. Stanistreet). The above listing gives some impression of the range of environmental settings and the wealth of processes and time-scales considered in this meaty volume. It is also a reminder that in less practised hands structural and depositional models could serve not to stimulate further enquiry but to inhibit it by supplying a terminology which begs both the products and their causes. The editors have skilfully steered their contributors away from the shoals of complacency. As they pointedly remark of one example, where exemplary field studies were assessed with due caution, a series of well documented earthquakes has left a disappointingly ambiguous sedimentary record. c.
VITA-FINZI
(London, U.K.)
SSDI 0037-0738(94)00107-3
Fluvial Sedimentary Geology and Geochronology of the Holocene Rhine-Meuse delta, The Netherlands. T.E. Tornquist. Netherlands Geographical
Studies, Utrecht University, 1993, 169 pp., Dfl.32 ISBN 90-6809-179-4. This slim book provides a wealth of sedimentological imformation on one of Europe’s great river systems, the Holocene Rhine-Meuse of the Netherlands. It is likely to become a major source for fluvial sedimentologists wishing to plunder it for data on avulsion periodicity and timing and the spatial and temporal development of anastomosing versus meandering channels. This is quite an impressive achievement for a doctoral thesis.
Geology 95 (1995) 287-291
In the serious Dutch scholarly tradition the book contains chapters that will be published separately as papers (some already are). Nevertheless the reader is highly recommended to purchase the whole book for such a modest price.The study was centred in a T-shaped area between Gorkum and Utrecht and made use of a staggering 500 shallow boreholes (drilled by a generation of students) and a large number of highly precise 14C dates, many of them by AMS. The 14C data base was analysed statistically by considering how single i4C dates are calibrated into probability distributions which are then summed to form calibrated histograms. The method avoids clustering of i4C ages in certain time intervals due to distortion of the i4C time scale by medium term 14C variations. The avoidance of artificial clustering is important when considering the timing of avulsions and thus the beginning and ending of fluvial activity in a particular channel segment.The author shows that both meander belts and anastomosed reaches characterised specific parts of the Rhine-Meuse alluvial plains during the Holocene. The meander belts are wider (width/ depth > 50) with wedge-shaped overbank deposits, whilst the narrower (w/d 15) anastomosed channels are associated with abundant and irregular crevasse splay deposits. The anastomosed channel networks seem only to occur in areas where the substrate consists of > 3-4 m of cohesive sediment or organic peats. It is also postulated that rapid rates of groundwater rise in these fine-grained sediments enhanced vertical accretion and encouraged anastomosed channel development.The author considers that Holocene sealevel rise has also strongly controlled avulsion in the Rhine-Meuse system. This section of the book deserves to be read by every serious fluvial sedimentologist. Using his 14C histogram technique the author studies the avulsion history of no less than 30 Rhine distributaries in the mid-late Holocene. The age data indicate that avulsions were nearly instantaneous, although some more gradual events occurred, and that avulsion frequencies were higher prior to about 4.3 ka when sea-level rise was rapid and the Dutch coast was open and tide-dominated. Subsequent rates have declined as the rate of rise itself declined and the
Book Reviews/Sedimentary
coast became corralled by barrier systems. The periods between avulsions (i.e. channel residence interval) were typically around 1.1 k 0.5 ky, with no difference in residence interval between the different types of channels. In addition to these points highlighted by the author, readers will doubtless discover many facts of interest to their own research. Thus I soon became engrossed in the Enclosure panels which show the legitimacy of compactional control (postulated years ago by John Bridge and the present reviewer) in determining the destiny of alluvinal channels after avulsion. I also wondered how the
Geology 95 (1995) 287-291
291
anastomosed channels managed to fill up so completely with sand-a tricky one for the author! I resolved to use the panels in my own teaching practicals. Any criticisms? The channels full up with sand was one. Perhaps more details of the 3D distribution of data points used to trace the course of the anastomosed reaches would re-assure the sceptical mind-the author relies on linear transects a great deal in his figures. MIKE LEEDER
SSDI 0037-0738(94)00111-1
(Leeds, U.K.)
Book Reviews /Sedimentary
Postma, A.R. Fortuin and W.A. van Wamel), Archaean and Cenozoic tectonic escape basins in S. Africa (I.G. Stanistreet), Pennsylvanian and Paleocene coal beds in the eastern USA (E.S. Belt), Plio-Pleistocene outer arc basins in Costa Rica (H. van Eynatten, H. Krawinkel and J. Winsemann), Mesozoic-Early Tertiary sedimentary evolution of the Antalya Complex in SW Turkey (A.H.F. Robertson), Plio-Quaternary sedimentation in the eastern Tyrrhenian (A. Argnani and F. Trincardi), and a Late Proterozoic accretionary prism in Central Namibia (P.A. Kukla and I.G. Stanistreet). The above listing gives some impression of the range of environmental settings and the wealth of processes and time-scales considered in this meaty volume. It is also a reminder that in less practised hands structural and depositional models could serve not to stimulate further enquiry but to inhibit it by supplying a terminology which begs both the products and their causes. The editors have skilfully steered their contributors away from the shoals of complacency. As they pointedly remark of one example, where exemplary field studies were assessed with due caution, a series of well documented earthquakes has left a disappointingly ambiguous sedimentary record. c.
VITA-FINZI
(London, U.K.)
SSDI 0037-0738(94)00107-3
Fluvial Sedimentary Geology and Geochronology of the Holocene Rhine-Meuse delta, The Netherlands. T.E. Tornquist. Netherlands Geographical
Studies, Utrecht University, 1993, 169 pp., Dfl.32 ISBN 90-6809-179-4. This slim book provides a wealth of sedimentological imformation on one of Europe’s great river systems, the Holocene Rhine-Meuse of the Netherlands. It is likely to become a major source for fluvial sedimentologists wishing to plunder it for data on avulsion periodicity and timing and the spatial and temporal development of anastomosing versus meandering channels. This is quite an impressive achievement for a doctoral thesis.
Geology 95 (1995) 287-291
In the serious Dutch scholarly tradition the book contains chapters that will be published separately as papers (some already are). Nevertheless the reader is highly recommended to purchase the whole book for such a modest price.The study was centred in a T-shaped area between Gorkum and Utrecht and made use of a staggering 500 shallow boreholes (drilled by a generation of students) and a large number of highly precise 14C dates, many of them by AMS. The 14C data base was analysed statistically by considering how single i4C dates are calibrated into probability distributions which are then summed to form calibrated histograms. The method avoids clustering of i4C ages in certain time intervals due to distortion of the i4C time scale by medium term 14C variations. The avoidance of artificial clustering is important when considering the timing of avulsions and thus the beginning and ending of fluvial activity in a particular channel segment.The author shows that both meander belts and anastomosed reaches characterised specific parts of the Rhine-Meuse alluvial plains during the Holocene. The meander belts are wider (width/ depth > 50) with wedge-shaped overbank deposits, whilst the narrower (w/d 15) anastomosed channels are associated with abundant and irregular crevasse splay deposits. The anastomosed channel networks seem only to occur in areas where the substrate consists of > 3-4 m of cohesive sediment or organic peats. It is also postulated that rapid rates of groundwater rise in these fine-grained sediments enhanced vertical accretion and encouraged anastomosed channel development.The author considers that Holocene sealevel rise has also strongly controlled avulsion in the Rhine-Meuse system. This section of the book deserves to be read by every serious fluvial sedimentologist. Using his 14C histogram technique the author studies the avulsion history of no less than 30 Rhine distributaries in the mid-late Holocene. The age data indicate that avulsions were nearly instantaneous, although some more gradual events occurred, and that avulsion frequencies were higher prior to about 4.3 ka when sea-level rise was rapid and the Dutch coast was open and tide-dominated. Subsequent rates have declined as the rate of rise itself declined and the
Book Reviews/Sedimentary
coast became corralled by barrier systems. The periods between avulsions (i.e. channel residence interval) were typically around 1.1 k 0.5 ky, with no difference in residence interval between the different types of channels. In addition to these points highlighted by the author, readers will doubtless discover many facts of interest to their own research. Thus I soon became engrossed in the Enclosure panels which show the legitimacy of compactional control (postulated years ago by John Bridge and the present reviewer) in determining the destiny of alluvinal channels after avulsion. I also wondered how the
Geology 95 (1995) 287-291
291
anastomosed channels managed to fill up so completely with sand-a tricky one for the author! I resolved to use the panels in my own teaching practicals. Any criticisms? The channels full up with sand was one. Perhaps more details of the 3D distribution of data points used to trace the course of the anastomosed reaches would re-assure the sceptical mind-the author relies on linear transects a great deal in his figures. MIKE LEEDER
SSDI 0037-0738(94)00111-1
(Leeds, U.K.)