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Quaternary environments
Book Reviews / Geomorphology 9 (1994) 77-82
6.10c, & 12.16b; Figs. 8.11, 8.13c & d, 8.28; Figs. 8. l ; 9.1, 11.23), as well as many photos that purport to show certain geological features but which lack adequate identifying marks, indication of geologic contacts, or other designations. The large number of illustrations, including the fine colored map and slipcase, are presumably the main reason for the most unreasonably high price. Probably the reason many otherwise fine books on the Himalaya are overloaded with photographs is because the landforms are so impressive, even good scientists become caught up in the beauty and boast of travel through such spectacular landscapes. In these times of ever spiraling costs, libraries will find it difficult to purchase this expensive book. Researchers with surplus grant monies may be able to afford the volume but most others will probably have to do without. This is unfortunate because the book does contain much valuable information, especially to those structural geomorphologists who are interested in long-term uplift-exhumation studies. Process geomorphologists will find less to interest them, as much of this material is better presented in the journals. SSDIO169-555X(93
) E0042-B
John F. SHRODER Jr. Omaha, NE. USA
Quaternary Environments. M.A.J. Williams, D.L. Dunkerley, P. de Deckker, A.P. Kershaw and T.J. Stokes. Edward Arnold, Hodder and Stoughton, Ltd., Kent, UK, 1993, 329 pp. Price: £ 16.95. Paperback. In their preface, the authors, all of whom are Australian and who, collectively, have accumulated a broad range of experience in Quaternary studies, point out that in the two decades since Flint (1972) and Butzer ( 1971 ) provided syntheses of the state of knowledge of the Quaternary much new has been learned. The first chapter is a summary of what follows in the volume. The author's briefly review the present understanding of the conditions that contributed to kinds of cyclical climatic changes that characterized the Quaternary. In their discussion of the effects of the migration of continental plates on the oceans and atmosphere during the Cenozoic (Chapter 2), they point out that global cooling has been progressing since the late Miocene,
81
which resulted in Northern Hemisphere ice sheets as early as 2.4 Ma. Discussion of the "Glacial Theory" is, perhaps, too brief and would have been helped by reference to Agazziz, who so effectively presented the idea to the world after he became convinced of its validity at Neuch~tel. Some of the statements in the treatment of continental ice sheets (pp. 35-36) seem to be contradictory. For example, statements that "...ice would melt by friction where movement is fast .... " but that ice flows slower in the zone of ablation because of reduced frictional heating (pp. 35-36), should have been referenced. Much of the southern margin of the Laurentide ice sheet probably was wet, with the basal ice near the freezing point; wet-base glaciers tend to flow rapidly. Some of the processes of till deposition described (pp. 36-37) should have included original sources to permit evaluation. Citation of additional sources for the extent of the Wisconsinan and older glaciations of North America would have been a useful supplement to the brief and highly generalized statements about this topic (i.e., Clayton and Moran, 1982, QS Reviews, 2; Richmond and Fullerton, 1986, QS Reviews, 5). In contrast to the brief and less than adequate treatment of the glacial and periglacial record, some of the more recent developments in the significance of oxygen isotopes in ice cores and cores of ocean sediments are well explained. Likewise, explanation for the sea level changes of the Quaternary are well reviewed. Processes and sediments of the oceans, along with some of the techniques for studying them (Chapter 5) provide enough detail for understanding isotope stratigraphy and an introductory discussion of the methods used in modeling past ocean temperatures. Because groundwater, rivers, and lakes involve primarily fresh water and are physically interrelated, the processes that result in them from changes in climate are presented in a single chapter (6). Following a discussion of the major factors that affected fluvial processes during the Quaternary, the authors chose 3 major fiver systems in widely separated environments as examples: the Nile, the Amazon, and the Murray-Murrnmbidgee-Darling systems. These three drainage basins illustrate the kinds of changes that the rivers must have undergone and the fragmented record left in sediments. River systems that drained one of the major continental glaciers, however, such as the MississippiMissouri of North America or. perhaps, the Rhine-
82
Book Reviews/Geomorphology 9 ~1994) 77-82
Main of Europe, differ from these three types enough that a discussion of one of them would have improved the coverage. The lake environment, in which sediments may record physical and biotic changes that take place on continents, is often given little space in discushions of the Quaternary. The text here, though brief, provides an introduction to limnic conditions and a look at the kinds of techniques available to decipher the paleo-environmental record of a lake. Arid regions (Chapter 7) have undergone complex sequences of environmental changes through late Cenozoic time. To help readers understand the sensitivily of such regions to the wide climatic swings of the Quaternary, the authors review the causes of aridity and the present distribution of arid regions of Earth. Some deserts of today were characterized by pluviality and lake-filled basins during glaciations, whereas other basins became dry or hypersaline during glacial maxima and lakes in them expanded during interglacial times. Margins of deserts shifted with the climatic changes. Large amounts of loess were generated from deserts during the Quaternary and from outwash surfaces during glacial maxima. Study of loess stratigraphy aids in interpretation of glacial and interglacial climatic conditions. Pollen studies have provided much of the present knowledge of terrestrial floral assemblages; thus a discussion of the dispersal and deposition of pollen grains and some of the problems of extraction and identification of pollen and the interpretation of pollen diagrams constitute a major part of chapter 8. Examples chosen for discussion came from Australia, eastern North America, and the British Isles. The authors point out thal plant macrofossils, along with vertebrate and invertebrate fossils, add to the data base for late Quaternary environmental interpretations. A brief summary of human evolution and migration constitutes Chapter 9. The final two chapters compare present-day atmospheric conditions and circulation with those of the last glacial maximum, as modeled by CLIMAP, and review
past and present climatic changes, projecting the effects produced by human cultures on the landscape and the atmosphere into the future. The authors conclude that we have considerable knowledge about the magnitudes and rates of environmental changes of the Quaternary, but we still have insufficient understanding of feedback mechanisms to project accurately the effects of the human-induced changes currently in progress. An appendix provides a concise summary of the methods of dating Quaternary materials that are currently in use, along with the limits of usefulness of each and the kinds of materials that can be dated by each method. The bibliographic list at the end of the volume contains more than 700 entries, nearly all of them in English, which the authors acknowledge in their preface. Most of the references were published in 1989 and the 2 decades that preceded that date, although a few are as recent as 1990 and 1991. It is not exhaustive, but does provide a good start, especially because many review papers are included. More citations to sources throughout the text of the book would have been appreciated, because some of the material was new to me or the authors presented ideas with which I disagreed, and I was unable to locate material for additional discussion of these points without a cited reference. The authors state that the book is intended primarily for upper-level undergraduates. Although the writing style bears this out, the paucity of citations to sources of data and interpretations expressed will make it difficult for most undergraduate students to search for more information without help. Nevertheless, the book does supply a concise and easily readable treatment of most of the major factors used to understand the climatic/environmental changes of the Quaternary. It will be a useful addition to library shelves, and those who teach a course about Quaternary Environments will want to consider it as a possible textbook. The book has been well edited; I discovered only two typographical errors, both minor. SSDIO 1 6 9 - 5 5 5 X ( 9 3 ) E0043-C
William J. W A Y N E
Lincoln. NE, USA
6.10c, & 12.16b; Figs. 8.11, 8.13c & d, 8.28; Figs. 8. l ; 9.1, 11.23), as well as many photos that purport to show certain geological features but which lack adequate identifying marks, indication of geologic contacts, or other designations. The large number of illustrations, including the fine colored map and slipcase, are presumably the main reason for the most unreasonably high price. Probably the reason many otherwise fine books on the Himalaya are overloaded with photographs is because the landforms are so impressive, even good scientists become caught up in the beauty and boast of travel through such spectacular landscapes. In these times of ever spiraling costs, libraries will find it difficult to purchase this expensive book. Researchers with surplus grant monies may be able to afford the volume but most others will probably have to do without. This is unfortunate because the book does contain much valuable information, especially to those structural geomorphologists who are interested in long-term uplift-exhumation studies. Process geomorphologists will find less to interest them, as much of this material is better presented in the journals. SSDIO169-555X(93
) E0042-B
John F. SHRODER Jr. Omaha, NE. USA
Quaternary Environments. M.A.J. Williams, D.L. Dunkerley, P. de Deckker, A.P. Kershaw and T.J. Stokes. Edward Arnold, Hodder and Stoughton, Ltd., Kent, UK, 1993, 329 pp. Price: £ 16.95. Paperback. In their preface, the authors, all of whom are Australian and who, collectively, have accumulated a broad range of experience in Quaternary studies, point out that in the two decades since Flint (1972) and Butzer ( 1971 ) provided syntheses of the state of knowledge of the Quaternary much new has been learned. The first chapter is a summary of what follows in the volume. The author's briefly review the present understanding of the conditions that contributed to kinds of cyclical climatic changes that characterized the Quaternary. In their discussion of the effects of the migration of continental plates on the oceans and atmosphere during the Cenozoic (Chapter 2), they point out that global cooling has been progressing since the late Miocene,
81
which resulted in Northern Hemisphere ice sheets as early as 2.4 Ma. Discussion of the "Glacial Theory" is, perhaps, too brief and would have been helped by reference to Agazziz, who so effectively presented the idea to the world after he became convinced of its validity at Neuch~tel. Some of the statements in the treatment of continental ice sheets (pp. 35-36) seem to be contradictory. For example, statements that "...ice would melt by friction where movement is fast .... " but that ice flows slower in the zone of ablation because of reduced frictional heating (pp. 35-36), should have been referenced. Much of the southern margin of the Laurentide ice sheet probably was wet, with the basal ice near the freezing point; wet-base glaciers tend to flow rapidly. Some of the processes of till deposition described (pp. 36-37) should have included original sources to permit evaluation. Citation of additional sources for the extent of the Wisconsinan and older glaciations of North America would have been a useful supplement to the brief and highly generalized statements about this topic (i.e., Clayton and Moran, 1982, QS Reviews, 2; Richmond and Fullerton, 1986, QS Reviews, 5). In contrast to the brief and less than adequate treatment of the glacial and periglacial record, some of the more recent developments in the significance of oxygen isotopes in ice cores and cores of ocean sediments are well explained. Likewise, explanation for the sea level changes of the Quaternary are well reviewed. Processes and sediments of the oceans, along with some of the techniques for studying them (Chapter 5) provide enough detail for understanding isotope stratigraphy and an introductory discussion of the methods used in modeling past ocean temperatures. Because groundwater, rivers, and lakes involve primarily fresh water and are physically interrelated, the processes that result in them from changes in climate are presented in a single chapter (6). Following a discussion of the major factors that affected fluvial processes during the Quaternary, the authors chose 3 major fiver systems in widely separated environments as examples: the Nile, the Amazon, and the Murray-Murrnmbidgee-Darling systems. These three drainage basins illustrate the kinds of changes that the rivers must have undergone and the fragmented record left in sediments. River systems that drained one of the major continental glaciers, however, such as the MississippiMissouri of North America or. perhaps, the Rhine-
82
Book Reviews/Geomorphology 9 ~1994) 77-82
Main of Europe, differ from these three types enough that a discussion of one of them would have improved the coverage. The lake environment, in which sediments may record physical and biotic changes that take place on continents, is often given little space in discushions of the Quaternary. The text here, though brief, provides an introduction to limnic conditions and a look at the kinds of techniques available to decipher the paleo-environmental record of a lake. Arid regions (Chapter 7) have undergone complex sequences of environmental changes through late Cenozoic time. To help readers understand the sensitivily of such regions to the wide climatic swings of the Quaternary, the authors review the causes of aridity and the present distribution of arid regions of Earth. Some deserts of today were characterized by pluviality and lake-filled basins during glaciations, whereas other basins became dry or hypersaline during glacial maxima and lakes in them expanded during interglacial times. Margins of deserts shifted with the climatic changes. Large amounts of loess were generated from deserts during the Quaternary and from outwash surfaces during glacial maxima. Study of loess stratigraphy aids in interpretation of glacial and interglacial climatic conditions. Pollen studies have provided much of the present knowledge of terrestrial floral assemblages; thus a discussion of the dispersal and deposition of pollen grains and some of the problems of extraction and identification of pollen and the interpretation of pollen diagrams constitute a major part of chapter 8. Examples chosen for discussion came from Australia, eastern North America, and the British Isles. The authors point out thal plant macrofossils, along with vertebrate and invertebrate fossils, add to the data base for late Quaternary environmental interpretations. A brief summary of human evolution and migration constitutes Chapter 9. The final two chapters compare present-day atmospheric conditions and circulation with those of the last glacial maximum, as modeled by CLIMAP, and review
past and present climatic changes, projecting the effects produced by human cultures on the landscape and the atmosphere into the future. The authors conclude that we have considerable knowledge about the magnitudes and rates of environmental changes of the Quaternary, but we still have insufficient understanding of feedback mechanisms to project accurately the effects of the human-induced changes currently in progress. An appendix provides a concise summary of the methods of dating Quaternary materials that are currently in use, along with the limits of usefulness of each and the kinds of materials that can be dated by each method. The bibliographic list at the end of the volume contains more than 700 entries, nearly all of them in English, which the authors acknowledge in their preface. Most of the references were published in 1989 and the 2 decades that preceded that date, although a few are as recent as 1990 and 1991. It is not exhaustive, but does provide a good start, especially because many review papers are included. More citations to sources throughout the text of the book would have been appreciated, because some of the material was new to me or the authors presented ideas with which I disagreed, and I was unable to locate material for additional discussion of these points without a cited reference. The authors state that the book is intended primarily for upper-level undergraduates. Although the writing style bears this out, the paucity of citations to sources of data and interpretations expressed will make it difficult for most undergraduate students to search for more information without help. Nevertheless, the book does supply a concise and easily readable treatment of most of the major factors used to understand the climatic/environmental changes of the Quaternary. It will be a useful addition to library shelves, and those who teach a course about Quaternary Environments will want to consider it as a possible textbook. The book has been well edited; I discovered only two typographical errors, both minor. SSDIO 1 6 9 - 5 5 5 X ( 9 3 ) E0043-C
William J. W A Y N E
Lincoln. NE, USA