the ice age world

2
Book reviews 343 Following four introductory chapters (among which a very useful one on the pre-Quaternary substratum) and two short chapters on pre-Saalian and Saalian (dealing mainly with surrounding areas), a larger part of the book treats the Eemian, Weichselian and post-glacial history of the region. Very useful are the tables documenting the above-mentioned interglacial and interstadial sites and their stratigraphic relationship. A special problem is the Middle Weichselian substage. The author shows convincingly that the peripheral sites must be conceptually separated from those found in the central part of former glaciation in Sweden and Finland. Evaluation of the biostratigraphical evidence and critical assessment of the radio carbon dating leads him to the conclusion that the latter (mainly in the range of 30 000-40 000 yr BP) are not reliable and should be discarded as evidence for Mid- Weichselian deglaciation of large parts of central and west- ern Sweden, northern Norway and Finland. Moreover, even in peripheral areas, not all radiocarbon datings previously used as evidence for deglaciation during the Middle Weich- selian have withstood critical re-evaluation. Notwithstanding, there is still ample evidence that areas such as southernmost Sweden and Denmark have been ice-free during that time- span, but the central parts of Scandinavia definitely were not, as discussed in Chapter 10. In this chapter the growth and dynamics of the ice-sheet of the last glaciation is illus- trated in much detail, much more detail than was possible only two decades ago. Deglaciation, a topic studied already early in this century is treated in a chapter of its own, here too presenting new data, including those on the present state of varve chron- ology, Late-glacial biostratigraphy, dating of some ash-falls and the history of the Baltic Ice lake. Chapters on Flandrian (Holocene) biostratigraphy and climate, land/sea-level changes, land mammals and a summary on geochronology finally conclude the synthesis. An extensive set of references will help the reader to find his way through the literature on the subject. The index is short, in my opinion too short, as some items (e.g. varves) cannot be found, even though they are amply discussed in the text. Illustrations are instructive and include many (palaeogeographic) maps. In summary this book is highly recommended to all inter- ested in an up-to-date and critical review of the extensive literature on Scandinavian glaciation and Quaternary stra- tigraphy. Especially the aforementioned evaluation of inter- glacial and interstadial beds is highly appreciated, but many more topics can be found. For students it is certainly the best introduction to the subject one could wish, even if the price may seem a problem for this group of users. WALDO H. ZAGWIJN Santport-Noord The Netherlands The Ice Age world B. G. ANDERSEN AND H. W. BORNS, JR Publisher Scandinavian University Press, Oslo, Copen- hagen, Stockholm 1994, US $ 42.50 (208 pp) ISBN 82-00- 21810-4 This is the most beautifully illustrated book on this topic that I know. It is full of colour photographs and colour diagrams that help the reader to obtain a good impression of the topic in question. For instance, there are three colour photographs of different Eemian soils (p. 45), and five colour photographs and a colour map of the Mid-Jutland end moraine (pp. 58-59). This splendid layout may awaken the interest of students in Quaternary studies, and even people who have worked in the subject more than a decade will find impressive pictures of relevant features that have rarely been published before - and never in colour. Both authors are experts in glacial geology. Consequently, glaciers and their deposits are the subject of a large part of the book. Nevertheless, the non-glacial aspects of the Quaternary are also dealt with. Well-drawn maps provide an impression of the North American landscape at 20000, 15 000 and 11 000 yr BP. Europe is shown in more detail at 20 000, 15 000, about 1 1 000, 9500, 9000 and 4000 yr BP. Unfortunately, no scale is given, so the reader needs to check with an atlas to discover the comparative sizes of the European and the North American ice sheets. The book starts with a ’historical review’, including the evolution of glacial theory, new dating techniques (with special emphasis on the deep-sea record), pre-Quaternary glaciations and the causes of ice ages. This chapter ends with a discussion of the geological time-scale. The extremely short duration of the Quaternary as compared with the older periods is emphasised. Chapter 2, the main part of the book, deals with Quatern- ary stratigraphy in North America and the area covered by the Scandinavian Ice Sheet in Europe. The British and Euro- pean Alpine Ice Sheets are mentioned in the text, but are discussed only briefly. The chapter includes remarkable photographs of deglaciation features in Scandinavia. The vast ice-dammed lakes of North America are also discussed briefly. At the end of the chapter short summaries are given of the Quaternary history of other continents, including Antarctica, and the Arctic region. The third chapter ‘Processes and Scientific Methods‘ con- tains an extended introduction to glacial and periglacial geomorphology. The methods part begins with a discussion of stratigraphy, including mention of various fossils used in biostratigraphy. Dating methods are discussed briefly, as well as lithological investigation techniques. Geological mapping is considered, and the last page of the chapter deals with economic aspects of Quaternary research. Some of these texts are extremely short. Although they certainly demon- strate to the reader that these aspects must be taken into account, it is a pity that no references are given. It is unavoidable in a book that covers such a broad range of topics like this that a few printing errors and mistakes occur. Lysefjord is not 457 km deep (p. 1 l), and the Treene lnterstadial (p. 170, fig. 4-7) is (if spelt with a double e and (ii) does not exist - at least at its type site. We Germans tend to put funny dots on various letters, but ’Urstromtal’ (p. 194) should not have any. Furthermore, topography does not allow one ‘Urstromtal’ to run right across northern Poland parallel to the Baltic Sea coast, as indicated in fig. 2- 25 (p. 61). The Ice Age World may be read by anyone with no previous knowledge of the Quaternary. This means, of course, that the text is relatively simple and may not always satisfy the advanced student. The book includes an ‘extended glossary’ 35 pages long, which represents a Quaternary geological dictionary of great value for any beginner in the field. Of especial value, not solely for the beginner, are diagrams such as comparison of the Wentworth and Atter- berg grain-size scales (p. 172) or the different types of folds and faults (p. 192).

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Page 1: The Ice Age world

Book reviews 343

Following four introductory chapters (among which a very useful one on the pre-Quaternary substratum) and two short chapters on pre-Saalian and Saalian (dealing mainly with surrounding areas), a larger part of the book treats the Eemian, Weichselian and post-glacial history of the region. Very useful are the tables documenting the above-mentioned interglacial and interstadial sites and their stratigraphic relationship.

A special problem is the Middle Weichselian substage. The author shows convincingly that the peripheral sites must be conceptually separated from those found in the central part of former glaciation in Sweden and Finland. Evaluation of the biostratigraphical evidence and critical assessment of the radio carbon dating leads him to the conclusion that the latter (mainly in the range of 30 000-40 000 yr BP) are not reliable and should be discarded as evidence for Mid- Weichselian deglaciation of large parts of central and west- ern Sweden, northern Norway and Finland. Moreover, even in peripheral areas, not all radiocarbon datings previously used as evidence for deglaciation during the Middle Weich- selian have withstood critical re-evaluation. Notwithstanding, there is s t i l l ample evidence that areas such as southernmost Sweden and Denmark have been ice-free during that time- span, but the central parts of Scandinavia definitely were not, as discussed in Chapter 10. In this chapter the growth and dynamics of the ice-sheet of the last glaciation i s illus- trated in much detail, much more detail than was possible only two decades ago.

Deglaciation, a topic studied already early in this century is treated in a chapter of its own, here too presenting new data, including those on the present state of varve chron- ology, Late-glacial biostratigraphy, dating of some ash-falls and the history of the Baltic Ice lake. Chapters on Flandrian (Holocene) biostratigraphy and climate, land/sea-level changes, land mammals and a summary on geochronology finally conclude the synthesis.

An extensive set of references will help the reader to find his way through the literature on the subject. The index is short, in my opinion too short, as some items (e.g. varves) cannot be found, even though they are amply discussed in the text. Illustrations are instructive and include many (palaeogeographic) maps.

In summary this book i s highly recommended to all inter- ested in an up-to-date and critical review of the extensive literature on Scandinavian glaciation and Quaternary stra- tigraphy. Especially the aforementioned evaluation of inter- glacial and interstadial beds is highly appreciated, but many more topics can be found. For students it is certainly the best introduction to the subject one could wish, even if the price may seem a problem for this group of users.

WALDO H. ZAGWIJN Santport-Noord

The Netherlands

The Ice Age world B. G. ANDERSEN AND H. W. BORNS, JR

Publisher Scandinavian University Press, Oslo, Copen- hagen, Stockholm 1994, US $ 42.50 (208 pp) ISBN 82-00- 21810-4

This i s the most beautifully illustrated book on this topic that I know. It is full of colour photographs and colour

diagrams that help the reader to obtain a good impression of the topic in question. For instance, there are three colour photographs of different Eemian soils (p. 45), and five colour photographs and a colour map of the Mid-Jutland end moraine (pp. 58-59). This splendid layout may awaken the interest of students in Quaternary studies, and even people who have worked in the subject more than a decade will find impressive pictures of relevant features that have rarely been published before - and never in colour.

Both authors are experts in glacial geology. Consequently, glaciers and their deposits are the subject of a large part of the book. Nevertheless, the non-glacial aspects of the Quaternary are also dealt with. Well-drawn maps provide an impression of the North American landscape at 20000, 15 000 and 1 1 000 yr BP. Europe is shown in more detail at 20 000, 15 000, about 1 1 000, 9500, 9000 and 4000 yr BP. Unfortunately, no scale is given, so the reader needs to check with an atlas to discover the comparative sizes of the European and the North American ice sheets.

The book starts with a ’historical review’, including the evolution of glacial theory, new dating techniques (with special emphasis on the deep-sea record), pre-Quaternary glaciations and the causes of ice ages. This chapter ends with a discussion of the geological time-scale. The extremely short duration of the Quaternary as compared with the older periods is emphasised.

Chapter 2, the main part of the book, deals with Quatern- ary stratigraphy in North America and the area covered by the Scandinavian Ice Sheet in Europe. The British and Euro- pean Alpine Ice Sheets are mentioned in the text, but are discussed only briefly. The chapter includes remarkable photographs of deglaciation features in Scandinavia. The vast ice-dammed lakes of North America are also discussed briefly. At the end of the chapter short summaries are given of the Quaternary history of other continents, including Antarctica, and the Arctic region.

The third chapter ‘Processes and Scientific Methods‘ con- tains an extended introduction to glacial and periglacial geomorphology. The methods part begins with a discussion of stratigraphy, including mention of various fossils used in biostratigraphy. Dating methods are discussed briefly, as well as lithological investigation techniques. Geological mapping is considered, and the last page of the chapter deals with economic aspects of Quaternary research. Some of these texts are extremely short. Although they certainly demon- strate to the reader that these aspects must be taken into account, it i s a pity that no references are given.

It i s unavoidable in a book that covers such a broad range of topics like this that a few printing errors and mistakes occur. Lysefjord is not 457 km deep (p. 1 l ) , and the Treene lnterstadial (p. 170, fig. 4-7) is (if spelt with a double e and (ii) does not exist - at least at its type site. We Germans tend to put funny dots on various letters, but ’Urstromtal’ (p. 194) should not have any. Furthermore, topography does not allow one ‘Urstromtal’ to run right across northern Poland parallel to the Baltic Sea coast, as indicated in fig. 2- 25 (p. 61).

The Ice Age World may be read by anyone with no previous knowledge of the Quaternary. This means, of course, that the text is relatively simple and may not always satisfy the advanced student. The book includes an ‘extended glossary’ 35 pages long, which represents a Quaternary geological dictionary of great value for any beginner in the field. Of especial value, not solely for the beginner, are diagrams such as comparison of the Wentworth and Atter- berg grain-size scales (p. 172) or the different types of folds and faults (p. 192).

Page 2: The Ice Age world

344 JOURNAL OF QUATERNARY SCIENCE

A major shortcoming of this impressive book is that no references are included. This makes it impossible to trace items of interest (in may case the Trollgaren end moraine, p. 12) or errors (such as the wrong ‘Urstromtal’) to their source. It also tends to conceal the fact that scientific pro- gress consists of many small steps, the results of which must be combined to result in a state-of-the-art overview of Quaternary research and a good textbook. The l ist of ’recommended literature’ (16 titles) i s much too short and a little out of date even after only 1 year. Two of the books have seen new editions by now, and other more recent titles (such as Hambrey’s Glacial Environments) should be added. The list of 13 journals quoted as ‘dealing with Quaternary aspects’ contains the right titles, but many more could be added - for instance, the two leading Canadian journals (Canadian Journal of Earth Sciences and Gkographie physique et Quaternairel.

As the authors say on the back of the dust jacket, the book is intended to stimulate interest in the Ice Age world. In this it certainly succeeds. Considering the high standard of production and the probably low number of copies printed, it is certainly moderately priced. However, it may prove to be more useful for the teacher than the student - a teacher who knows the story behind the pictures, which can be used to illustrate lectures, and who can also add at least some references.

Reference HAMBREY, M . 1994. Glacial Environments.

296 pp. UCL Press, London,

JURGEN EHLERS Geologisches Landesamt

Billstr. 84 20539 Hamburg

Germany