Periglacial processes

Periglacial processes

QUATERNARY RESEARCH 10, 135-139 (1978) BOOK REVIEWS Periglacial Processes. Benchmark Papers in Geology, Vol. 27. Edited by C. A. M. King. Dowden, ...

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QUATERNARY

RESEARCH

10,

135-139 (1978)

BOOK REVIEWS Periglacial Processes. Benchmark Papers in Geology, Vol. 27. Edited by C. A. M. King. Dowden, Hutchinson and Ross, Inc., Stroudsburg, Pa., 459 pp.

A series of benchmark papers is meant to reflect historical milestones in the development of a subject. These may be either significant advances of a substantive or theoretical nature or may mark the commencement of new avenues of scientific endeavour. Periglacial Processes, the latest in the Benchmark Papers in Geology series falls short of these objectives and fails to do justice to the very significant advances made recently in the field. At a time when there is increasing interest in permafrost regions and when our understanding of frost action and permafrost-related processes is accelerating at an everincreasing rate, it is unfortunate that an opportunity to place these new developments in their proper historical perspective has been lost. Criticisms can be leveled in two general directions: first, at the overall choice of papers, and second, at the editors commentary by which the inclusion of any particular paper is justified. For example, this collection of papers, purportedly dealing with our understanding of periglacial processes, does not include even one paper published by either a Soviet or Polish scientist. This exclusion ignores the detailed and voluminous permafrost literature existing in the Soviet Union and downgrades the overwhelming influence of Polish geomorphologists in the study of periglacial environments. Regarding the Soviet literature, technical translations of certain papers are now available, notably those by the National Research Council of Canada, and a wealth of information is now easily accessible and widely disseminated by the volumes accompanying the First and Second International Permafrost Conferences, held at Purdue University, Lafayette, Ind., in 1963, and Yakutsk, U.S.S.R., in 1973. Regarding the Polish work, a characteristic has been a willingness to publish in other languages, particularly English and French. However, none of the very influential and extensive writings of J. Dylik, for many years editor-in-chief of the Biuletyn Peryglacjalny and Chairman of the IGU Commission on Periglacial Geomorphology, has been included in this volume. Furthermore, periglacial geomorphology developed historically as a branch of climatic geomorphology, and the input of continental Europeans such as J. Budel, A. Cailleux, J. Tricart and C. Troll is not recognized. A second broad criticism is that the volume tends

to neglect many of the more recent advances made in our understanding of permafrost-related processes. For example, none of the recent, post-1965 work of J. R. Mackay, published mainly in the Canadian Journal of Earth Sciences, is included. Yet his series of papers upon the permafrost and ground-ice conditions of the Mackenzie Delta must surely be recognized as an outstanding example of detailed quantitative field investigation which, over a decade, has culminated in significant theoretical advances. Equally sad is the treatment given to fluvial processes. Two pages from E. de K. Leffingwell’s 1919 paper describing aufeis are followed by a general and obscure paper dealing with the aggradation of streams under periglacial climates. When the editors’ commentary is included, a grand total of 11 pages out of a total of over 400 is devoted to fluvial processes. Such a brief treatment, while reflecting an obvious neglect of fluvial processes in the past, does nothing to remedy this deficiency. For example, the nature of fluvio-thermal erosion, first described by H. J. Walker in 1963 from the Colville Delta of Northern Alaska, ought to have been included. Also missing is the work of M. Church who, between 1964 and 1970, pioneered the use of quantitative hydrologic techniques in the study of High Arctic streams. These criticisms become more apparent when the individual papers and the overall plan of the book are considered. A total of 36 papers, either in full or in part, are grouped under six headings: frost action and ground ice formation, mass wasting, snow action, wind action, fluvial action, and marine action. The papers themselves constitute approximately 80% of the volume with the editorial commentary at the beginning of each section making up the remainder. Less than half of the papers would be regarded by this reviewer as being benchmark papers. Some deal primarily with morphology rather than process, some are of a review nature, and others must fairly be regarded as of only local importance. The first section, dealing with frost action and ground ice, contains a number of true benchmarks, notably the early observations of E. de K. Leffingwell upon permafrost and ground ice, the paper by A. Lachenbruch dealing with thermal contraction cracking, the experimental work upon frost heave and sorting by S. B. Taber and A. Corte, respectively, the two papers by A. L. Washburn upon patterned ground classification and origin, and J. R. Mackay’s 1962 pingo paper in which the closed system hypothesis is first fully developed. The remaining papers in this section are not in the same category, although wellresearched. In the opinion of this reviewer, a number 135 0033-5894/78/0101-0135$02.00/O Copyri&t 0 1978 by the University of Washington. AU rights of reproduction in my form reserved.

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BOOK

REVIEWS

of other papers should have either been included or at least mentioned in the editorial commentary. For example, no recent papers deal specifically with permafrost. Yet the thermal, hydrologic, and terrain aspects of permafrost must be clearly understood if permafrostrelated processes are to be correctly analyzed. Ignoring the extensive Soviet literature on these topics and restricting discussion to North America, the paper of D. M. Hopkins on groundwater in Alaska in 1955, A. Lachenbruch’s analysis of permafrost thermal regimes in 1957, and R. J. E. Brown’s papers upon permafrost distribution, particularly in the discontinuous zone, ail represent accessible baseline data from which subsequent work has evolved. It is also regrettable that no mention is made of the Soviet theoretical work on thermal contraction cracking, pioneered by B. N. Dostovalov in 1958 and subsequently extended by N. N. Romanovski in 1973. Likewise, J. R. Mackay’s important 1973 paper on the growth mechanisms of pingos should not have been omitted. To complete things, the 1970 paper on Siberian thermokarst by T. Czudek and J. Demek and published in Quaternnry Research should have been included since it represented the first formal presentation of the Soviet thermokarst experience in the North American literature. Section II deals with mass wasting and includes 10 papers. Several are real benchmarks, notably those by J. G. Andersson in 1906 and J. B. Benedict in 1970 upon solifluction and downslope soil movement. and that by A. Rapp upon the denudation of cliffs and talus slopes in Spitsbergen. Many of the other papers, however, do not deal directly with mass wasting processes; one describes rock glaciers in Alaska, another protalus ramparts in Utah, and a third blockfields in Norway. Three further papers, none necessarily benchmark contributions, describe cryopediments. altiplanation terraces, and asymmetrical slope development. Thus, one searches in vain for A. Jahn’s classic 1961 paper dealing with the quantitative measurement of slope processes in Spitsbergen, for A. Rapp’s work at Karkevagge in 1961, and for J. Dylik’s 1969 papers on slope evolution at Waiewice in central Poland. The remainder of the volume comprises 12 papers divided into four sections dealing with snow, wind, fluvial, and marine action. Papers by W. V. Lewis on snow patch erosion, A. Rapp and N. Caine upon talus slope formation and avalanche activity, B. Fistrup upon wind erosion, and M. Pecsi upon loess deposition highlight important processes directly associated with either wind or snow. The indirect effects of these two processes, however, often operating in association, are not considered. For example, the inclusion of a paper on valley asymmetry would have emphasized how differential snow covers induce more solifluction on lee slopes leading to lateral stream migration and

valley asymmetry. Another indirect effect of snow is its influence upon the ground thermal regime, particularly in the discontinuous permafrost zones. The importance of snow and wind, therefore, goes far beyond the direct easily observable effects reported in this volume which gives an overly simplistic view of these important processes. The final section deals with marine action and comprises two useful papers by J. D. Hume and M. Schalk, and R. L. Nichols. describing ice pushing and beach characteristics of polar regions. The inclusion of a third paper, outlining the influence of permafrost upon coastal erosion in ice rich and unconsolidated sediments. would have also been appropriate. These comments may make this review overly critical of Professor King’s selection of papers. Judging from this volume, however, a reader wishing to obtain either an historical overview of periglacial processes or a state-of-the-art review of current achievements will either be misinformed or disappointed. Our understanding of frost action and permafrost-related processes is much greater than this volume suggests. Unfortunately, the volume will merely reinforce the opinion of those who regard periglacial geomorphology as just another branch of a rather unscientific climatic geomorphology. It is particularly sad that an opportunity to rectify this latter impression has not been achieved in the editorial commentary. For the most part, it shows little regard for either precision or perception. In the introductory comments, for example, the editor specifically defines an “active zone” in contradiction to the generally accepted term “active layer” but then proceeds to use the latter throughout the rest of the book. The elementary error of equating the base of the active layer with the permafrost table is committed on p. 5. There is mention of “thaw-freeze” rather than “freeze-thaw” processes. and of fossil ice wedges in temperate mid-latitudes rather than ice wedge casts. Fossil ice wedges need permafrost for their preservation, as in central and southern Alaska. and ice wedge casts result from their melting. Finally. with regard to the general presentation of the volume, each paper is reproduced in its original type setting, thus leading to an uneven and unaesthetic quality of reproduction. The photographs are not always of good quality, Plate 3B (p. 432) is upside down, and Figure I of G. F. Mitchell’s paper (p. 143) appears now to have been reproduced by the kind permission of three unnamed fossil pingos.

HUGH

Department

of Geography Ottawa,

and Regional University Ontario, Canada

M.

FRENCH

Planning 0j’Utiawa KIN GN5