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Meteorites and their origins
2706
Book reviews
Abbey (Geol. Surv. of Canada) and Shapiro (U.S. Geological Survey}-are given only passing mention or are omitted. One of the major problems in practical AA spectrometry, that of preparing and ~~ibrating standards, is given insuf&ient attention. The role of analyzed reference materials in the control of geochemioal analysis is ignored. Despite these faults, the book accumulates a good deal of useful information, and will be of value as a general guide to anyone beginning use of the technique, presuming they have access to other sources. C. 0. INGAMELLS Climax Molybdmwn Co., Golden, Colomdo 80401, U.S.A.
E&eoritea and Their Origins by G, 5. MCCALL. David & Charles, 1973, 352 pp. $4.95 AN IMPORTANT result of the Apollo and Luna programs is the realization that terrestrial, lunar and meteoritic materials record different periods in, and processes of, Solar System evolution. The returned lunar samples raise far more questions than they answer, and the information now strea~g back from Mars suggests that this planet too will broaden rather than narrow our perspective. Though present manpower and support statistics do not reflect it, planetary research remains an active, expanding field in which the study ofmeteorites continues to play an important part. Most of the general texts on meteorites (e.g. Mason, Heide) predate the flood of meteoritic research performed during the early and middle 1960’s. The sole exception, Wood’s 1968 book, is excellent in what it treats but not broad enough to provide a general int~duetian to the field. There is a clear need for a readable, comprehensive, up-to-date, and autho~tative summary of what we know and think about meteorites. G. J. McCall has attempted to meet this need with a book which he describes as “a general text for amateur scientists, university students and professional scientists.” In attempting to summarize a very broad, controversial field for three different audiences, the author set himself a very difficult task. It is not surprising that Meteoritesalzd The3 0~igina is only partly successful: it achieves its goals of ~~ab~ity and ~omp~he~iveness, but it is by no means up-to-date and it is authoritative in only a very narrow sense of the word. Among the attractions of the book are an informal style, sparing use of exotic terminology, and a wealth of illustrations, most of which are well-chosen and well-reproduced. These and a remarkably small number of typographical errors make the book easy and enjoyable to read. In the sense that it touches on virtually all aspects of meteorites, McCall’s txeatment of the subject is oomprehensive. The &st half ofthe book is largely descriptive. It includes chapters on the history of meteoritic research, ~trono~ea1 co~iderations, fall phenomena, mo~holo~, classification and the properties of individual meteorite types. This part of the book, in effect an introduotion to the materials, organization and terminology of the soience, is generally wellrealized. I regret the brevity of the chapter on classification, which will probably leave the beginner thoroughly bewildered. The rest of the material is well-chosen and illustrated in a manner much like that of earlier texts. The second half of the book treats problems and issues raised by meteorites. It includes chapters on brecciation; the significance of the carbon~eous chondrites; ~hondrules; metamorphism in meteorites; organic matter and life forms; meteorite ages and isotopic data; and the origin of meteorites. The Iast four chapters deal with tektites and craters, whose relation to meteorites McCall regards as greatly overrated. McCall’s treatment of these topics is very disappointing, chiefly because it is based largely on old data and arguments and omits more recent ones. For example, a table of elemental
2707
Book reviews
abundanoes in meteorites is drawn from Levin (1956). As many elements were very poorly known before the massive influx of data in the 1960’s, Levin’s tabulation seriouslymisrepresents present knowledge. Likewise, a brief discussionof trace element patterns in the iron meteorites includes Wood’s (1963) summary of yet older data, but ignores the extensive recent data of the UCLA group. In many instances, the absence of recent data affects the course of McCall’s discussion. For example, he notes the apparent anomaly between solar and chondriticiron abundanoesbut does that not mention recent adjustments of the solar data which appearto resolveit. As he ctoncludes type I carbonaceous chondrites are not primitive objects, the omission is significant. Another omission with strong interpretive overtones is that of Binns’ (1967) contribution to the issue of brecciation in meteorites. McCall’s review of several instances of polymiet brecciation leaves the reader persuaded that meteorites of various types were closely related in spaoe, time, and passably, mode of origin. Binns’ study showed convincinglythat ~scegenation is at least rare among the various chondrite groups, a point which makes it quite diEieult to derive them all from the same parent body. A final example will sufilce to underscore the problem. In his chapter on the origin of ohondrules, the author lists thirteen theories-including some whose authors have recanted publicly. He omits two models (impact and lightning fusion-ten and seven years old, respectively) which are now favorably entertained by many workers. Moreover, in expressing his preferencefor Mueller’s (1953) theory, he fails to discussevidenceagainst it and other ‘secondary’ models, though much of this evidence was cogently summarized by Wood a decade ago. In his Introduction, McCall acknowledgeshis strong relianceon reviewpapers, many of which are quite old. In the reviewer’sjudgement, his debt to such sourcesis far too large: all texts are obsolete on publication, but this one is more so than it needs to be. It is also strongly biased toward the author’s interpretations at many points. &f&all’s conclusionson chondrules,the significanceof carbonaceouschondrites, the origin of tektites and the role of volcanism on the lunar surface diverge strongly from those of other workers. This is not undesirablein itself-we progress, after all, through argument. What is undesirable is his failure to acknowledge the evidence for, and in some cases the existence of, other interpretations. By omitting these, he has made the second half of his book less a survey of meteoritic6 than a summary of one man’s view of it. It remains impossible to direct amateurs and students to a single adequate textbook on meteor&es. The first half of M&all’s book is an attractive, and more modern, alternative to Mason or Heide for a general int~duction to the field. For a modern and balanced view of the questions posed by meteorites, Wood’s 1968 book remains an excellent choice. Departmentof Earth and space Xciencas, State University of New York, at Stomy Brook, New York 11790, U.S.A.
Proceedings of the Third ~o~e~nee
on Origins of L~e-Pl~et~
MARG~~~s. Springer-Verlag, New York (1973) 268 pp. $1430.
R. T. DODD
~~~orny,
edihd by LYNX
is an edited, informal dialogue among scientistsfrom diversedisciplinesattending the third in a seriesof conferenceson the origins of life. In this conference,considerationsare given to the implication that studies of the Moon and Mars have had in determiningthe origins of life. The general format of the book is similar to the record of the two preceding conferences; the usefulnessof such meeting-transcriptsremains questionable. Unless the readeris used to reading plays having difficult plots and casts of at least nineteencharacters, he will find the present book hard to assimilate. Fortunately, the editor has helped the reader by dividing the text into two major (the Moon and Mars) and sixteen minor subhe~ngs, but ~fo~~ately the publisher THIS BOOK
Book reviews
Abbey (Geol. Surv. of Canada) and Shapiro (U.S. Geological Survey}-are given only passing mention or are omitted. One of the major problems in practical AA spectrometry, that of preparing and ~~ibrating standards, is given insuf&ient attention. The role of analyzed reference materials in the control of geochemioal analysis is ignored. Despite these faults, the book accumulates a good deal of useful information, and will be of value as a general guide to anyone beginning use of the technique, presuming they have access to other sources. C. 0. INGAMELLS Climax Molybdmwn Co., Golden, Colomdo 80401, U.S.A.
E&eoritea and Their Origins by G, 5. MCCALL. David & Charles, 1973, 352 pp. $4.95 AN IMPORTANT result of the Apollo and Luna programs is the realization that terrestrial, lunar and meteoritic materials record different periods in, and processes of, Solar System evolution. The returned lunar samples raise far more questions than they answer, and the information now strea~g back from Mars suggests that this planet too will broaden rather than narrow our perspective. Though present manpower and support statistics do not reflect it, planetary research remains an active, expanding field in which the study ofmeteorites continues to play an important part. Most of the general texts on meteorites (e.g. Mason, Heide) predate the flood of meteoritic research performed during the early and middle 1960’s. The sole exception, Wood’s 1968 book, is excellent in what it treats but not broad enough to provide a general int~duetian to the field. There is a clear need for a readable, comprehensive, up-to-date, and autho~tative summary of what we know and think about meteorites. G. J. McCall has attempted to meet this need with a book which he describes as “a general text for amateur scientists, university students and professional scientists.” In attempting to summarize a very broad, controversial field for three different audiences, the author set himself a very difficult task. It is not surprising that Meteoritesalzd The3 0~igina is only partly successful: it achieves its goals of ~~ab~ity and ~omp~he~iveness, but it is by no means up-to-date and it is authoritative in only a very narrow sense of the word. Among the attractions of the book are an informal style, sparing use of exotic terminology, and a wealth of illustrations, most of which are well-chosen and well-reproduced. These and a remarkably small number of typographical errors make the book easy and enjoyable to read. In the sense that it touches on virtually all aspects of meteorites, McCall’s txeatment of the subject is oomprehensive. The &st half ofthe book is largely descriptive. It includes chapters on the history of meteoritic research, ~trono~ea1 co~iderations, fall phenomena, mo~holo~, classification and the properties of individual meteorite types. This part of the book, in effect an introduotion to the materials, organization and terminology of the soience, is generally wellrealized. I regret the brevity of the chapter on classification, which will probably leave the beginner thoroughly bewildered. The rest of the material is well-chosen and illustrated in a manner much like that of earlier texts. The second half of the book treats problems and issues raised by meteorites. It includes chapters on brecciation; the significance of the carbon~eous chondrites; ~hondrules; metamorphism in meteorites; organic matter and life forms; meteorite ages and isotopic data; and the origin of meteorites. The Iast four chapters deal with tektites and craters, whose relation to meteorites McCall regards as greatly overrated. McCall’s treatment of these topics is very disappointing, chiefly because it is based largely on old data and arguments and omits more recent ones. For example, a table of elemental
2707
Book reviews
abundanoes in meteorites is drawn from Levin (1956). As many elements were very poorly known before the massive influx of data in the 1960’s, Levin’s tabulation seriouslymisrepresents present knowledge. Likewise, a brief discussionof trace element patterns in the iron meteorites includes Wood’s (1963) summary of yet older data, but ignores the extensive recent data of the UCLA group. In many instances, the absence of recent data affects the course of McCall’s discussion. For example, he notes the apparent anomaly between solar and chondriticiron abundanoesbut does that not mention recent adjustments of the solar data which appearto resolveit. As he ctoncludes type I carbonaceous chondrites are not primitive objects, the omission is significant. Another omission with strong interpretive overtones is that of Binns’ (1967) contribution to the issue of brecciation in meteorites. McCall’s review of several instances of polymiet brecciation leaves the reader persuaded that meteorites of various types were closely related in spaoe, time, and passably, mode of origin. Binns’ study showed convincinglythat ~scegenation is at least rare among the various chondrite groups, a point which makes it quite diEieult to derive them all from the same parent body. A final example will sufilce to underscore the problem. In his chapter on the origin of ohondrules, the author lists thirteen theories-including some whose authors have recanted publicly. He omits two models (impact and lightning fusion-ten and seven years old, respectively) which are now favorably entertained by many workers. Moreover, in expressing his preferencefor Mueller’s (1953) theory, he fails to discussevidenceagainst it and other ‘secondary’ models, though much of this evidence was cogently summarized by Wood a decade ago. In his Introduction, McCall acknowledgeshis strong relianceon reviewpapers, many of which are quite old. In the reviewer’sjudgement, his debt to such sourcesis far too large: all texts are obsolete on publication, but this one is more so than it needs to be. It is also strongly biased toward the author’s interpretations at many points. &f&all’s conclusionson chondrules,the significanceof carbonaceouschondrites, the origin of tektites and the role of volcanism on the lunar surface diverge strongly from those of other workers. This is not undesirablein itself-we progress, after all, through argument. What is undesirable is his failure to acknowledge the evidence for, and in some cases the existence of, other interpretations. By omitting these, he has made the second half of his book less a survey of meteoritic6 than a summary of one man’s view of it. It remains impossible to direct amateurs and students to a single adequate textbook on meteor&es. The first half of M&all’s book is an attractive, and more modern, alternative to Mason or Heide for a general int~duction to the field. For a modern and balanced view of the questions posed by meteorites, Wood’s 1968 book remains an excellent choice. Departmentof Earth and space Xciencas, State University of New York, at Stomy Brook, New York 11790, U.S.A.
Proceedings of the Third ~o~e~nee
on Origins of L~e-Pl~et~
MARG~~~s. Springer-Verlag, New York (1973) 268 pp. $1430.
R. T. DODD
~~~orny,
edihd by LYNX
is an edited, informal dialogue among scientistsfrom diversedisciplinesattending the third in a seriesof conferenceson the origins of life. In this conference,considerationsare given to the implication that studies of the Moon and Mars have had in determiningthe origins of life. The general format of the book is similar to the record of the two preceding conferences; the usefulnessof such meeting-transcriptsremains questionable. Unless the readeris used to reading plays having difficult plots and casts of at least nineteencharacters, he will find the present book hard to assimilate. Fortunately, the editor has helped the reader by dividing the text into two major (the Moon and Mars) and sixteen minor subhe~ngs, but ~fo~~ately the publisher THIS BOOK