The reconstruction of ancient marine environments is an important task of the Earth Sciences, of great interest to geology, pure and applied, to oceanography and climatology, as well as to such fields as ecology and evolution. In principle, such reconstructions are based on the actualistic approach of "the present is the key to the past." Since the deciphering of past environmental changes, either nat ural or man-made, has considerable bearing on planning, the past may provide a key to the future. Paleoenvironmental interpretations in the marine realm are based to a great extent on assemblages of fossils recovered from ancient sediments in outcrops and from land-based or submarine drillings. Observable lateral sequences of assemblages in contemporaneous strata, the known or assumed functional or adaptive significance of preserved skeletal struc tures, as well as their evolution through time and space, provide by themselves indications of ancient environmental settings. In some cases even present-day eco logical considerations may be derived from analysis of fossils."

The African continent is unique in that it has escaped widespread orogenic activity after the Pan African orogenic event. Therefore, the African Plate provides the world's best example of the relationship between extensional magmatism and structural setting. This first complete and up-to-date review, written by leading scientists, discusses the evolutionary model and offers a new and reliable basis for scientists working on plate tectonics and extensional areas in other continents.

Fifty million years ago, the Arctic Ocean was a warm sea, bounded by lush vegetation of the warm-temperate shores of Scandinavia, Siberia, Alaska and the Northwest Territories. Wind and storms were rare because Atlantic weather systems had not developed but, as today, polar day length added a hostile element to this otherwise tranquil climate.
With the aid of scientists from all the countries close to the Arctic Circle, this book describes the palaeontology, the statistical analysis of vegetational features, comparisons with atmospheric, marine, and geological features and some of the first models of plant migration developed from newly constructed databases.

The fifth volume in this series is focused on the chemical and physical interactions between rocks undergoing metamorphism and the fluids that they generate and that pass through them. The recognition that such pro cesses can profoundly affect the course of metamorphism has resulted in a number of recent papers and we consider that it is time for a review by some of the interested parties. We hope our selection of contributors provides an adequate cross section and demonstrates some of the flavor of this rapidly developing field. A cursory examination of the volume will reveal that there are widely divergent opinions on the compositions of metamorphic fluids and on the ways in which they interact physically and chemically with the rocks through which they pass. Since our own views are extensively discussed in Chapters 4 and 8, we leave the reader to determine his own brand of the "truth. " We wish to thank D. Bird, S. Bohlen, D. Carmichael, G. Flowers, C. Foster, C. Graham, E. Perry, J. Selverstone, R. Tracy, J. Valley, and R. Wollast for their chapter reviews. Thanks are also due C. Cheverton for her editorial assistance, and the helpful staff at Springer-Verlag New York."

Colloid science has been applied by soil chemists and clay mineral ogists for many years, and some of the most important studies on the behavior of colloids have been contributed by them. Barring a few notable exceptions, only in the last decade have geochemists applied colloid science in their research and in this period much work has been published. It seemed to the authors that it would be useful at this stage to attempt to summarize the progress made and to try to examine what colloid science has contributed and can further contribute to geo chemistry. This book is based partly on a course of the same title given to graduate students by one of the authors (S. Y) between 1972 and 1977 at the Department of Geology at the Hebrew University of Jerusalem. Consequently many fundamental concepts of the subject are included that will be of use to graduate students in geology, geo chemistry, soil science, and oceanography. So that specialists interested in certain sections may find their subjects comprehensively covered, a few topics are dealt with in more than one chapter so that readers may ignore sections not especially of interest to them. However the chapters more fully treating certain topics are cross-referenced. In such cases the subjects are treated from different viewpoints and the citations used represent these dif fering viewpoints."

The Northwest African and the conjugate Northeast American con- tinental margins provide excellent examples of mature passive continental margins which record in their thick sediment cover the birth and evolution of the Atlantic Ocean Basins during the past 200 million years. Due to a dense net of single- and multichannel seismic reflection lines, numerous Deep Sea Drill- ing Project (DSDP) sites and petroleum exploration wells, and the well-known onshore geology, the Northwest African margin is one of the bes"t-documen ted margins of the world. A particu- lar advantage of this margin is that its coastal basins are well exposed and accessible for detailed stratigraphic studies and onshore-offshore correlations, whereas the Mesozoic-Ceno- zoic marginal basins off eastern North America underlie only the present continental shelf and slope. During the past decade, the Northwest African margin was stu- died in great detail, particularly by the Woods Hole Oceano- graphic Institution, Lamont-Doherty Geological Observatory, Imperial College London, Shell Internationale Petroleum Maat- schappij (Den Haag), Kiel University, and the Bundesanstalt fiir Geowissenschaften und Rohstoffe (BGR) at Hannover. A num- ber of important synthesis papers summarized these results; e. g. , Summerhayes et al. , 1971; Dillon and Sougy, 1974; Seibold and Hinz, 1974; Uchupi et al. , 1976; Lehner and de Ruiter, 1977 (all quoted in the references of Seibold, this Vol. ).

The present book is devoted to the study of the deep Earth's interior structure, one of the most important problems of Earth sciences today. The drilling of the Kola superdeep well inaugurated a new stage in the study of the Precambrian continental crust. The well was sunk in the northeastern part of the Baltic Shield, in an area where the Precambrian ore-bearing structures, typical of the ancient platform basements, are in juxtaposition with each other. To the present the well has been drilled to a depth of 12 km, has traversed the full thickness of the Proterozoic complex and a considerable part of the Archean stratum, and is still be ing worked on. This book reviews the principal results of investigations to a depth of 11,600 m; these are described in three sections: geology, geophysics, and drilling. The book begins with a general review of the history, the present state of knowledge, and trends of further investigations in the field of study of the Earth's interior and superdeep drilling. The first section of the book considers the geology of the vicinity of the Kola superdeep well and describes its geological section based on a detailed examination both of the cores and the near-borehole area."

This book explores the basic principles and methods of paleomagnetology and gives a systematic description of paleomagnetic phenomena such as geomagnetic reversals, paleosecular variations, long-term intensity changes and apparent polar wandering paths. Special emphasis is laid on results obtained from research work done in the Soviet Union. Together with data from other parts of the world they allow the critical discussion of aspects of magnetostratigraphy, plate tectonics and accretion tectonics. In diesem Buch werden grundlegende Fragen der Palaomagnetologie und des Palaomagnetismus abgehandelt. Durch die Einbeziehung zahlreicher Daten aus der Sowjetunion werden Probleme der Magnetostratigraphie sowie der Platten- und Akkretionstektonik kritisch beleuchtet.

Students of a phenomenon as common but complex as andesite genesis often are overwhelmed by, or overlook, the volume and diversity of relevant information. Thus there is need for periodic overview even in the absence of a dramatic breakthrough which "solves the andesite problem" and even though new ideas and data keep the issues in a state of flux. Thus I have summarized the subject through mid.1980 from my perspective to help clarify the long-standing problem and to identify profitable areas for future research. Overviews are more easily justified than achieved and there are fundamental differences of opinion concerning how to go about them. It is professionally dangerous and therefore uncom mon for single authors, especially those under 35 such as I, to summarize a broad, active field of science in book-length thor oughness. Review articles in journals, multi-authored books, or symposia proceedings appear instead. The single-authored approach is intimidating in scale and can result in loss of thoroughness or authority on individual topics. The alternatives lack scope or integration or both."

Syntheses of the geology of major areas of the Earth's crust are increasingly needed in order that the features of, and the problems associated with, the secular evolution of the continents can be understood by a wide audience. Southern Africa is fortunate in having a remarkable variety of geological environments developed without many breaks over 3. 8 Ga, and many of the rock groups are household names throughout the geological world. In one respect the geology of Southern Africa is particularly important: cratonization clearly began as early as 3. 0 Ga ago, in contrast to about 2. 5 Ga in most other continental areas such as North America. This book documents very well the remarkable change in tectonic conditions that took place between the Early and Mid-Precambrian; we have here evidence of the very earliest development of rigid lithospheric plates. This book is a tribute to the multitudes of scientists who have worked out the geology of Southern Africa over many years and decades. Whatever their discipline, each provided a step in the construction of this fascinating story of 3. 8 Ga of crustal development. In the book the reader will find a detailed review of the factual data, together with a balanced account of interpretative models without the indulgence of undue speculation. One of its attractions is its multidisciplinary approach which provides a stimulating challenge to the reader.

This book represents the results of a lengthy study which Professor ALFRED RITTMANN began some thirty years ago. The relationship between the chemical and mineralogical composition of igneous rocks is established as far as is possible. Petrographers will appreciate that this problem is extremely complex, particularly since this relationship forms the basis of the classification and nomenclature of igneous rocks. The ingenious scheme of calculation of the CI.P.W. norm system is essentially chemical in nature. The compositions of the stoichiometrically ideal "normative minerals" do not correspond to those of the constituent minerals found in rocks. Although the "norm" is not intended to equal the "mode" or actual mineral composition of a rock, at least a qualitative agreement between the norm and the mode is desirable. For a number of rocks and rock groups, especially the leucocratic and silicic rocks, the deviation of the norm from the mode is generally within tolerable limits. For the melanocratic and highly subsilicic rocks, on the other hand, the CI.P. W. scheme of calculation too often yields results which fail to reflect the observed mineral composition. The anomalies produced in the cal culation of extremely subsilicic volcanic rocks have recently been briefly discussed by F. CHAVES and H. S. YODER, JR. (1971)."

This volume contains the lectures presented at the NATO Advanced Study Institute that took place at the University of Delaware, Newark, Delaware, July 18-27, 1982. The purpose of this Institute was to provide an international forum for exchange of ideas and dissemination of knowledge on some selected topics in Mechanics of Fluids in Porous Media. Processes of transport of such extensive quantities as mass of a phase, mass of a component of a phase, momentum and/or heat occur in diversified fields, such as petroleum reservoir engineer ing, groundwater hydraulics, soil mechanics, industrial filtration, water purification, wastewater treatment, soil drainage and irri gation, and geothermal energy production. In all these areas, scientists, engineers and planners make use of mathematical models that describe the relevant transport processes that occur within porous medium domains, and enable the forecasting of the future state of the latter in response to planned activities. The mathe matical models, in turn, are based on the understanding of phenomena, often within the void space, and on theories that re late these phenomena to measurable quantities. Because of the pressing needs in areas of practical interest, such as the develop ment of groundwater resources, the control and abatement of groundwater contamination, underground energy storage and geo thermal energy production, a vast amount of research efforts in all these fields has contributed, especially in the last t o decades, to our understanding and ability to describe transport phenomena."

The Mediterranean Sea, nestled between Africa, southern Europe, and the Middle East, may be envisioned as a complex picture-puzzle comprising numerous intricate pieces, many of which are already in place. A general image, in terms of science, has emerged, although at this time large gaps are noted and some areas of the picture remain fuzzy and indistinct. In recent years this fascinating, mind-teasing puzzle image has become clearer with individual pieces more easily recognized and rapidly emplaced, largely by means of multidisciplinary and multinational team efforts. In this respect, the Special Program Panel on Marine Sciences of the NATO Scientific Af fairs Division considered the merits of initiating four conferences bearing on the Mediterranean ecosystem. It was suggested that the first, emphasizing geology, should dovetail with subsequent seminars on physical oceanogra phy, marine biology, and ecology and man's influence on the natural Medi terranean regime. At a conference held in Banyuls-sur-Mer, France, in August 1979, Profes sor Raimondo Selli was urged by some panel members to initiate an Ad vanced Research Institute (ARI) that would focus primarily on the geologi cally recent evolution of the Mediterranean Sea and serve as a logical base for future NATO conferences on the Mediterranean."

The study of paleocurrents, since 1963, is now a very routine part of sedimentology, and more and more such studies are finding use in other fields. Thus it seemed appropriate for us to review post-1963 developments and present them in a compact manner for the interested reader. Instead of rewriting a second edition, which thirteen years later we would organize in a completely dif ferent way, we have brought each chapter up to date with new material up to 1976. A new update supplement has in this edition been inserted after each one of the original chapters. We have stayed close to the original theme of paleocurrents-how to measure them and how to use them to solve geological problems ranging in scale from the hand specimen to the sedimentary basin and beyond. We have used many annotated references and tables to help pre sent this information to the reader. The reader will note that we have cited a few 1962 references - pUblications that appeared too late to be cited in the original 1963 edition. A few times we have also cited a reference which was included in the first edition. These are marked with an asterisk and hence do not appear in the new lists of references. We have been aided by many. In Cincinnati, WANDA OSBORNE and JEAN CARROL did typing and RICHARD SPOHN, the University's geological librarian, was very helpful in obtaining many references to the literature."

Earthquakes come and go as they please, leaving behind them trails of destruc tion and casualties. Although their occurrence is little affected by what we do or think, it is the task of earth scientists to keep studying them from all possible angles until ways and means are found to divert, forecast, and eventually control them. In ancient times people were awestruck by singular geophysical events, which were attributed to supernatural powers. It was recognized only in 1760 that earthquakes originated within the earth. A hundred years later, first systematic attempts were made to apply physical principles to study them. During the next century scientists accumulated knowledge about the effects of earthquakes, their geographic patterns, the waves emitted by them, and the internal constitution of the earth. During the past 20 years, seismology has made a tremendous progress, mainly because of the advent of modern computers and improvements in data acquisi tion systems, which are now capable of digital and analog recording of ground motion over a frequency range of five orders of magnitude. These technologic developments have enabled seismologists to make measurements with far greater precision and sophistication than was previously possible. Advanced computational analyses have been applied to high-quality data and elaborate theoretical models have been devised to interpret them. As a result, far reaching advances in our knowledge of the earth's structure and the nature of earthquake sources have occurred."

The Geo-Platinum 87 Symposium, held at the Open University during April 1987, was designed as a forum for presentation of new research results on the occurrence, genesis, geochemistry, mineralogy and analysis of the platinum-group elements (PGE). With the support of the Open University and the Mineral Industry Research Organisation, the symposium was attended by 115 representatives of university departments, research institutions and members of the mining and mineral exploration industries. An introduction to the symposium was provided by two invited papers from C. J. Morrissey (Riofinex North) and C. R. N. Clark (Johnson Matthey) which were designed to give perspective to the goals of PGE research work. The first of these papers gave a provocative insight into the aims and objectives of an exploration manager, examining the influence of supply, demand and perceived world reserves on exploration strategy. The second invited paper gave a valuable view of the industrial uses, market trends and predicted changes in the commercial value of the platinum-group elements from the standpoint of a refining company and supplier. These invited papers are reproduced in this volume and are followed by twenty four full papers and twenty abstracts that reflect the wide range of research topics presented at the symposium."

You might well wonder why TFPC in Practice is a part of the Monographs in Visualization series. However, if you really think about typesetting, especially fine typesetting, you soon realize that in large part it is a visual art as well as a science. 'lEX's algorithms produce in almost all cases aesthetic results of the highest quality. On the other hand, occasionally one may want to insert some additional space before a subscript or superscript, or one may want to adjust the vertical spacing in a fraction. Fortunately Donald Knuth, the author of 'lEX, allows one to program such corrections easily where needed. The four volumes of Stephan von Bechtolsheim's long awaited TFPC in Prac tice present a comprehensive view of 'lEX. His thorough discussion of each aspect of 'lEX is liberally laced with cogent illustrative examples. Many of these exam ples represent complete, ready to use macros that enhance the capabilities of 'lEX. These examples are of particular interest to both the typesetter and the 'lEX programmer. The typesetter can often solve an immediate problem by ei ther using one of the examples directly or by making minor changes to adapt it to the problem at hand. The 'lEX programmer can use the examples, along with Stephan's detailed discussion, to increase both the depth and breadth of his or her knowledge of 'lEX. The value of the text is further enhanced by Stephan's concerted effort to explain the reasoning behind each topic or example."

From a general point of view the importance of striving to minimize envir- mental disturbances on the continental shelf cannot be overemphasized. Coastal areas are sites of population centers, navigation and recreation activities, and - source development, all of which contribute to environmental stress on the shelf. Proper management of the shelf for optimum use requires a thorough understanding of shelf processes. Complex problems, such as the influence of hydrodynamics on sediment dispersal, element differentiation and migration, physiochemical changes at the sediment water interface, the relationship - tween the pollutants and sediments, and the type of substrate with regard to benthic community and/or man-made structures require a multidisciplinary approach to their solution. The present study interrelates meteorologic, hyd- graphic, sedimentologic, and geochemical parameters to derme specific envir- ments on the Alaskan Shelf. These observations are then related to geologic principles in an effort to elucidate the sedimentary processes and elemental migration on the shelf. Attempts have also been made to relate the sediment texture to the geochem- try of the sediments. Obviously the chemistry is complicated as a result of b- genic contributions and variable provenance; however, to some extent elemental differentiation accompanies textural differentiation in sediments. The distribution of elements in various phases of crustal (source) rocks is gen- ally interpreted on the basis of crystallographic concepts, especially the concept of isomorphism.

TEX has always been regarded as the most elegant and powerful system for computer typesetting. However, its widespread use, beyond academia, was hampered by its complexity. Recently, fairly good TEX implementations have come out for PCs putting TEX on the desks of many people: writers, designers, desktop publishers, engineers, and consequently, the interest in TEX has surged. What is needed at this point is a book that teaches step-by-step how to use TEX, illustrating each step by meaningful examples. This is exactly what S.v. Bechtolsheim's book does. It is a tutorial and guide for the first-time users of TEX, as well as a reference for the most experienced "TEXpert." TEX in Practice will appear as a four volume set, starting with volume 1 "Basics," followed by volume 2 "Paragraphs, Math and " "Fonts," volume 3 "Tokens, Macros" and volume 4 "Output Routines, " "Tables." TEX in Practice will be an indispensable reference for the TEX community and a guide through the first steps for the TEX novice.

Recent research has produced a large number of results concerning the Stone-Cech compactification or involving it in a central manner. The goal of this volume is to make many of these results easily accessible by collecting them in a single source together with the necessary introductory material. The author's interest in this area had its origin in his fascination with the classic text Rings of Continuous Functions by Leonard Gillman and Meyer Jerison. This excellent synthesis of algebra and topology appeared in 1960 and did much to draw attention to the Stone-Cech compactification {3X as a tool to investigate the relationships between a space X and the rings C(X) and C*(X) of real-valued continuous functions. Although in the approach taken here {3X is viewed as the object of study rather than as a tool, the influence of Rings of Continuous Functions is clearly evident. Three introductory chapters make the book essentially self-contained and the exposition suitable for the student who has completed a first course in topology at the graduate level. The development of the Stone Cech compactification and the more specialized topological prerequisites are presented in the first chapter. The necessary material on Boolean algebras, including the Stone Representation Theorem, is developed in Chapter 2. A very basic introduction to category theory is presented in the beginning of Chapter 10 and the remainder of the chapter is an introduction to the methods of categorical topology as it relates to the Stone-Cech compactification."

Although you only have one volume in front of you, writing four volumes and 1600 pages on a single subject needs some form of justification. And then on the other hand, why write even more?! Can't, at least, the preface of something that long be short?! Very well, so let's keep it short. It is my sincere hope that the series "'lEX in Practice" will be useful for your own 'lEX work. But please, before you get started, read the "Notes on ''lEX in Practice' ," because it instructs you how to use this series. You will find these notes on pages xxvii-xxxvi. The fourth and last volume deals with two different subject areas. First of all, there are the so-called output routines which are responsible for putting together the pages as generated by 'lEX. You will be amazed at how many different things can be done with 'lEX's output routines. The second subject area we are dealing with in this volume are tables. About a hundred different tables you can choose from should provide you with a starting point in the selection of tables.

Floods, earthquakes, hurricanes and typhoons are the major natural disas ters in the world, among which the least understood are seismogenic processes_ With highly concentrated populations and rapidly developing economy, social requirements for earthquake prediction are becoming more and more pressing. The seismic region in Mainland China is situated at the eastern edge of the Eurasian seismic system, and is the largest intracontinental region of shallow strong earthquakes in the world, as a result of the collision of the Indian Ocean plate and the underthrusting of the west Pacific Ocean plate. Since the beginning of this century, there have been on average two strong earthquakes of Mover 7 every 3 years,of which at least one has caused catastrophic losses. From 1966 to 1976,China was struck by successive large earthquakes, of which nine with M over 7 (that is, the 1966 M7. 2 Xingtai earthquake;the 1969 M7. 4 Bohai earthquake; the 1970 M7. 7 Tonghai earthquake;the 1973 M7. 9 Luhuo earthquake; the 1974 M7. 1 Yongshan earthquake; the 1975 M7. 3 Haichang earthquake; the 1976 M7. 4 Longling earthquake; the 1976 M7. 8 Tangshan earthquake; the 1976 M7. 2 Songpan earthquake) occurred in the densely popu lated areas east of longitude 98 0 E, causing very severe casualties and damage. According to statistics, about 300,000 people have been killed by these earthquakes.

Probability theory and its applications represent a discipline of fun damental importance to nearly all people working in the high-tech nology world that surrounds us. There is increasing awareness that we should ask not "Is it so?" but rather "What is the probability that it is so?" As a result, most colleges and universities require a course in mathematical probability to be given as part of the undergraduate training of all scientists, engineers, and mathematicians. This book is a text for a first course in the mathematical theory of probability for undergraduate students who have the prerequisite of at least two, and better three, semesters of calculus. In particular, the student must have a good working knowledge of power series expan sions and integration. Moreover, it would be helpful if the student has had some previous exposure to elementary probability theory, either in an elementary statistics course or a finite mathematics course in high school or college. If these prerequisites are met, then a good part of the material in this book can be covered in a semester (IS-week) course that meets three hours a week."

The NATO Advanced Research Workshop on "The Effects of the Mt. Pinatubo Erup tion on the Atmosphere and Climate" was held in Rome, September 26-30, 1994. In addition to NATO, the workshop was supported by Accademia Nazionale dei Lincei. The Organizing Committee was fortunate to enlist the participation of many of the experts in the field, and this book is an account of their contributions. The eruption of Mt. Pinatubo in June 1991 was readily recognized as one of the major eruptions of the century. In a sense it was the global experiment the atmospheric scientific community was waiting for to assess theories developed on ozone depletion and greenhouse warming. In September of that same year the launching of the UARS satellite added a new tool for observers all around the world. Three years later was a good time to convene a NATO Workshop to sum up what had been measured and theorized about the effects of the eruption. This book is divided in four chapters which cover respectively: the characterization of the aerosol cloud, the measured or simulated effects on temperature, on ozone and on climate.

Advances in seismology and extensions of its application have made it increasingly necessary to perform high-sensitivity observationsonartificial earth tremors (explosions) or on natural ones. This implies in particular to investigating the seismic conditions in large industrial centres. There are many major cities with a million inhabitants or more in seismically-active regions. In the USSR, this applies to the capitals of the Union Republics such as Alma Ata, Frunze, Tashkent, Dushanbe, and Ashkhabad, as well as to dozens of local entres and cities with extensive industrial development. Seismic classification and earthquake forecasting have to be considered in relation to the extension or building of cities in such regions, and this would be impossible without detailed investigation of the seismicity, which involves upgrading the instru mental observation network. The demand for detailed information on the seismicity increases with every extension to the construction. A successful solution here can be implemented only by taking account of some specific factors, the main one being the high level of seismic noise due to the activities in large centres, which restricts the sensitivity of the apparatus and makes it impossible to record weak local earth tremors, which are of particular interest in periods of relative seismic calm. Stations at sufficiently great distances from the city do not sense the city noise, but they also fail to record weak local earth tremors. Also, the accuracy ofobservation falls for those tremors that can be recorded because of the great distances between stations."