Tracers in the sea

Tracers in the sea

1336 Book Reviews 9. Com~sitio~ Zoning and Inchsions in ,~etamor~~ic Minerals (R. J. Tracy) This chapter reviews the use of zoning and inclusion pat...

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1336

Book Reviews

9. Com~sitio~ Zoning and Inchsions in ,~etamor~~ic Minerals (R. J. Tracy) This chapter reviews the use of zoning and inclusion patterns in garnet as records of prograde and r$rograde P-T paths. It should be clear from the foregoing that no serious student of metamorphic rocks can afford not to master the material in this book. It is perhaps worth reflecting on the fact that essentially all of the methods of thermodynamic analysis of metamorphic systems described in this work

Traeara in the Sea by W. S. Brcecker and T. H. Peng. Eidigio Press Lamont Lhhuty Gcolo(licaiObservatory, 1982,690 pages (300 fr8ures and tab& 740 commented bibliographic references), us $35.00 WALLYBROECKERand TSUN;-HUNG PENG have just published “Tracers in the Sea”. “Chemical Oceanography” had been written by WaRace Broecker 10 years ago, before Geesets, befbre much of the DSDP, before sediment traps, before the development of the various climate programs. So muchmoreisnowunden&oodoftheOceansystem.so many more tracux are in current use that it is impossible to~~~~~a~~~nof~e~~ch as ‘chemical Oceanography”. And indeed “Tracers in the sea” is suhstaritiai! The book indudes most of the material of the former one but with much updat&. After an introductory chapter on the oceanic cycles and the inputs f?om continents to oceans. it eoes on with the formation and comer&on of sediments, indudinp v nodules, and the exchaneg with the atmosphueandthecycieofgusm.Chapter5.alsoonthe rate of sedimentation, is in its principles close to that from “Chemical ocanognphy”. But then. more mcent data and concepts come in: Chapter 4 on the cycle of trace metals antlpartkksintheseaintagratmthegreataumberofmuhs on tcactive radiou&ve ttaara the study of sediment trap ~~~~~ly~~~~on~~rn~ in~~.~7~~~e~~f~~~ and how they am bc identified and fbtlowed in the deep ocean; Chapter 8 considers the probiern of mixing through the main themmchne and upwelling in equatoti areas. The invasion of the oceans by antimmgmic tritium and bombproduced ‘4c is addies& there. The control mechanisms of the major cations and nutrients in the sea are approachedinChapter6;theseccmceptaareusedinChapter 9 to deactii the glacial to intet@a&i m of the climate, ocean &em&try and circuiation and sedimentation. Finally Chapter 10d&ussesthebuiidupoftheCQcontentofthe atmosphere, the kinetics of its uptake by the surthce and deepoaananditsuRimate&xtsonsediments. Thesuhjectscoveredamverybrtx&thegoakwereambitioq the resuit is mmarkable. Ah the main ingredients which made ‘Qemical wy” very usefui have been ret&~& beautiiul w&i% for b&ztnerx an exce&nt ~,f~~a~~neofi~~~~ and ckar &urns. The best is the presentation of the intricacies in the use of the di&nat tracers and concepts, which

Dopdta, Vol.1, No. 1 and 2, published by the Association of Mineml &!posits, Gaokigical Society of China and Institute of Mineral Deposits, and the Chinese Academy of Geoiogicai Sciences. 1982,94p and 96~. Mlwd

which are the heart of modem chemical petrology originated with Jim Thompson and Hugh Greenwood. This book consists of oustanding review and tutorial contributions by leaders in their respective fields, offered at a sensible price. One can only hope that this type ofpublishing venture will be taken up by other scientific societies. Depanmen!

oj Geoiogy & Geophysics

Raymond Joesten

University of Cormecfictrl Sforrs, CT 06268

so few of us can keep in mind ah the time. Two factors greatly contribute to the unity of the text. The first is the “COr problem” and the carbon cyck in the ocean, which is examined in nearly every chapter. I would agree that it is indeed one of the major present problems in earth sciences! Tha second is the constant use of box models, in particular in the problems and super-problems which end up the di&unt chapters. The same way of thinking is thus used throughout the volume, prolpaoively complexiikd as km&edge is inaeased. This bobk is very personai: it represents mostly Wally Broecker’s intemsts. It is certainiy not a pale and neutral review of the fidd. This makes it exciting. As a result of course_ some of the modeis are somewhat disputable, such as that for uputeiiing in equatorial ragions (Chapter 8); but on the other hand, some others are as yet unpubhshed, such as the reinterpretation of the Two Degree Discontinuity (Chapter 7). Of coutxe. some aspects are baruly described, such as rekaae of major and trace elements fmm sediments but the principles of this are presented for calcite (Chapter 2). Of course. the actual chemical reactions and pmcesses which control the behavior of reactive metals are not discussed, but what do we really know of this subject? To my own taste, two aspects could be presented in a slightly &f&rent way. The description of the kinematics of the movements of the water masses as deduced from chemical v~cgs &ii on some undemtanding of the dynamics of these movements (Chapters 7 and 8). While teeching this matter, I aiwaya found it di3icuIt to separate both and cxp&in why the different models for chemical tracers have been developed. Secondly, I find box mod& sometimes more dilgcult to appmhend and discuss than diffinntial ones. Thii is in particuhu the case for control mechanisms (Chapter 6). Is it really such a prubkm to prexent differential equations to oceanqpaphy students? But this is minor with mgard to the importance and quality of “Tracers of the W. I am already using it frequently to retrieve a value, a reference, a 8gure or the eB&ts deciphered by a 8iven tracer. I know I will draw heavily from it for my teaching. For all our forthcoming students, I want to thank WaIly Broeeker and Tsung-Hung Peng Laboratoire de Geachimk et Cosmackimie Institute de Pitysique du G&e &part-t des Sciences de Ia Tkre Uniwtsites de Paris VI et Ylf 4 P&e hsieu 75230 Paris Cedex 04, FRANCE

J.-F. Minster

MRJERALDEPOSITS is a new journal dealing with the economic geology of mineral deposits of mainland China. The journal is pubhshed jointly by the Association of Mineral Deposits. the Geological Society of China and Institute of