but also in the geological problems in which he is attempting to apply them. The coverage of this chapter addresses both the difficulty and controversy of the subject matter with extensive illustrations and applicable references espousing several different points of view. Chapter 6 addresses the problem of automated or semi-automated well-to-well correlation. This subject is of considerable interest because it strikes at the heart of the problems involved in establishing zoned initial models and/or constraints for heterogeneous reservoir and/or aquifer simulators and attempting to predict what happens between control wells. This chapter makes a very strong case for the use of computer aided interactive work stations. Chapter 7 is a speculative look at the uses of artificial intelligence software for well log analysis. The presentation in this chapter reflects
Meteorite Cruters and Impact Structures Cambridge University Press, Cambridge, $49.50 (ISBN O-521-36092-7).
ofthe Earth by Paul Hodge. 1994, viii + 124 pp. US
DESPITEcurrent interest in the events at the Cretaceous-Tertiary boundary during the last 15 years, impact cratering remains one of the least studied and most unappreciated geological processes. However, a small group of interdisciplinary scientists has been studying the impact process and its signatures over several decades, generating an impressive body of data. Impact cratering is the most important surface-modifying process on all planets and satellites with a solid surface (and the recent impact of comet Shoemaker-Levy 9 on Jupiter has shown that not even gas giants are immune from such events). On Earth, we are in the unique position of being able to provide ground truth for impact cratering by studying impact structures on our planet. In contrast to observations of craters on other planets, which can only be done by remote sensing techniques (with the exception of some very limited additional studies of lunar craters), such investigations on Earth can include geological, geophysical, geochemical, mineralogical, and petrographical aspects. About 150 impact structures have been identified on Earth, allowing these kinds of detailed investigations. The present volume offers portraits of I39 terrestrial impact craters. A short introduction on impact cratering (4 pages) is followed by seven geographically divided chapters on impact craters in the United States, Canada, Latin America, Australia, Europe, Africa, and Asia. Within these chapters, the craters are listed alphabetically. For each crater, some basic data (location, diameter, age) are given, followed by a short description of the structure, often a map of a photograph, occasionally directions on how to find the structure, and one or two (rarely more) references. An index follows at the end of the book. The book is well written and easy to understand, and is a kind of portrait gallery or travelogue of impact craters around the world. There is only so much information that can be included in a thin, 124 page, volume like this. As a brief introduction to an interested, but not well-informed audience, this book serves a good purpose. It should also be available in all earth science libraries, because it is of
A Color Atlos qf Rocks und Minerals in Thin Section by W. S. MacKenzie and A. E. Adams. Halsted Press, John Wiley and Sons, Inc.. 1994, 192p.. paperback, US $29.95 (ISBN O-470-23338-9). A Color Atlas of Rocks and Minerals in Thin Section is an introduction to the study of minerals and rocks in thin section. The authors have included a very limited discussion of mineral optics; however, the primary purpose of the book is to illustrate the common minerals and rocks in thin section with color photomicrographs accompanied by brief descriptions of each. The text is divided into five parts. Part I is devoted to optical mineralogy and includes a description of a basic petrographic microscope. Part 1 also includes discussions of mineral properties that are important to their identification in thin section, including crystal shape and habit, color, pleochroism, cleavage, relief, birefringence,
the youth of the techniques in that it is more ephemeral and has fewer examples than the previous chapters. More of this chapter is devoted to trying to explain just how the techniques work than to examples of their usage. Geologic Log Analysis Using Computer Methods is an excellent reference for experienced well log analysts and subsurface geologists wishing to expand their ideas and skills. As I read through the book, I found myself repeatedly recalling my own past projects which would have benefitted from techniques showcased in this book. Weiss Associates 5500 Shellmound St. Emeryville. CA 94608. USA
Donald G. Hill
great value as a reference book. However, there are limitations in its use for the interested geologist, geochemist, geophysicist, etc. I have no complaints about the content of the book, although 1 am a bit disappointed about what is not in the book. The introduction is too short to be of use for a textbook, for example. The listings for craters are of greatly differing length, ranging from only one sentence (e.g.. “Zapadnaya is in central Ukraine, southwest of Kiev.” Period.this is all we are told about this crater! ) to more than a full page. This reflects somewhat the differences in our knowledge about vatious craters, but in some instance, one sentence is not good enough. 1 would have thought the minimum information for each crater should include a brief description of its geological setting and the evidence for impact, and to which extent it has been studied. Unfortunately, this kind of information is only given for some of the better studied craters. The reference list is also a bit disappointing. While it is very convenient to list full references after each crater, there is a lot of repetition. I have not counted how often the full reference to Richard Grieve’s 1991 compilation of impact craters in Meteoritics (from which the author has derived his crater listing) is given, but it is mentioned a lot, wasting quite some space. Furthermore, it does not help the reader who wants to learn more about a particular crater and the evidence for its impact origin to be referred to another compilation. Also, I tind that one or two references are often not enough for many of the better studied craters. One message I hope will be extracted from this book is that many terrestrial craters have not been well studied, and to point out how much potential for geological research remains. Thus, while the lack of critical review of our current understanding of individual craters limits the value of this book for specialists. it should nevertheless be a teaser for all those who are interested in meteorite impact craters. The book is well produced and has a moderate price that should make it attractive to both individuals and libraries. Institute of Grochemisttyv University of Vienna Dr.-Kurl-LueRer-Ring I A-1010 Vienna, Austria
extinction angles, twinning, zoning, and alteration. An important limitation in Part I is the lack of any discussion concerning conoscopic illumination, Part 2 illustrates a few of the rock-forming minerals that are important for the identification of the most common rocks including olivine, pyroxenes, amphibole, biotite, muscovite, chlorite, quartz. feldspars, nepheline, calcite and garnet. In general, this section consists of pairs of photomicrographs illustrating the same thin sections in both plane-polarized light and with crossed polars. Part 3 begins with a brief description of the origin and classitication of igneous rocks followed by several pairs of photomicrographs illustrating the textures and mineral compositions of some of the most common igneous rocks including peridotite, basal&, gabbros, andesite, diorite, granodiorite, rhyolite, granites, phonolite, syenite, leucitite, lamprophyre, and ignimbrite.