ALBERT

Description / Table of Contents: PREFACE In the geologic record, vertical crustal uplift has often resulted in erosional removal of huge thicknesses of sedimentary strata. If the uplift is of a broad regional nature or the uplifted strata remain relatively undeformed and sediments deposited after the uplift are not preserved, the magnitude of uplift and subsequent erosion may be difficult to quantify. This may lead to misinterpretation or omission of chapters of geologic history of a region. Fortunately, a number of indirect methods can be used to infer the thicknesses of missing strata and reconstruct the geologic history. Our book titled "Thick Post-Devonian Sediment Cover Over New York State: Evidence from Fluid-Inclusion, Organic Maturation, Clay Diagenesis and Stable Isotope Studies" uses four techniques of paleotemperature measurements in sedimentary rocks in order to determine burial depths of the existing Paleozoic strata in New York State. Since every technique has its own analytical and interpretative uncertainties, the use of four techniques allowed us to place a better constraint on our results. We show how regionally extensive paleotemperature data can be used to estimate the thicknesses of strata lost from an uplifted sedimentary basin. We also provide a tentative tectonic-, paleogeographic- and depositional history of New York State after the Devonian when the missing strata were deposited...

Description / Table of Contents: Pages 1-13 / Maars of the Westeifel, Germany / G. Büchel --- Pages 15-60 / Syn- and post-eruptive mechanism of the Alaskan Ukinrek Maars in 1977 / G. Büchel, V. Lorenz --- Pages 61-80 / Maars and maar lakes of the Westeifel Volcanic Field / Jörg F. W. Negendank, Bernd Zolitschka --- Pages 81-94 / Maars of northern Auvergne (Massif Central, France): State of knowledge / E. Juvigné, G. Camus, A. de Goër de Herve --- Pages 95-107 / Palaeoenvironmental investigations on long sediment cores from volcanic lakes of Lazio (central Italy)—An overview / Maria Follieri, Donatella Magri, Biancamaria Narcisi --- Pages 109-116 / Geophysical mapping of organic sediments / Stefan Wende, Reinhard Kirsch --- Pages 117-118 / Preliminary uniboom survey of the Monticchio Lakes (southern Italy) / A. Stefanon --- Pages 119-128 / Sonar investigations in the Laghi di Monticchio (Mt. Vúlture, Italy) / Ralph B. Hansen --- Pages 129-148 / Climatic and tectonic effects on sedimentation in central Italian volcano lakes (Latium)—Implications from high resolution seismic profiles / F. Niessen, A. Lami, P. Guilizzoni --- Pages 149-161 / Sediments and basin analysis of Lake Schalkenmehrener Maar / T. Heinz, B. Rein, J. F. W. Negendank --- Pages 163-171 / Organic carbon contents of sediments from Lake Schalkenmehrener Maar: A paleoclimate indicator / B. Rein, J. F. W. Negendank --- Pages 173-194 / Basin analysis for selected time-frames using sedimentation rates in Lake Meerfelder Maar (Westeifel FRG) / F. Wegner, J. F. W. Negendank --- Pages 195-208 / Turbidites in the sediments of Lake Meerfelder Maar (Germany) and the explanation of suspension sediments / D. Drohmann, J. F. W. Negendank --- Pages 209-222 / Paleoclimate reconstruction at the Pleistocene/Holocene transition—A varve dated microstratigraphic record from Lake Meerfelder Maar (Westeifel, Germany) / D. Poth, J. F. W. Negendank --- Pages 223-235 / Paleoenvironmental reconstruction of the Late- and Postglacial sedimentary record of Lake Weinfelder Maar / A. Brauer, J. F. W. Negendank --- Pages 237-275 / Sedimentology and paleoenvironment from the Maar Lac du Bouchet for the last climatic cycle, 0-120,000 years (Massif Central, France) / Elisabeth Truze, Kerry Kelts --- Pages 277-288 / Lago Grande di Monticchio (southern Italy) a high resolution sedimentary record of the last 70,000 years / Bernd Zolitschka, Jörg F. W. Negendank --- Pages 289-304 / A multidisciplinary study of the Vico Maar sequence (Latium, Italy): Part of the last cycle in the Mediterranean area. Preliminary results / P. Francus, S. Leroy, I. Mergeai, G. Seret, G. Wansard --- Pages 305-316 / Environmental geology and geochemistry of lake sediments (Holzmaar, Eifwl, Germany) / B. G. Lottermoser, R. Oberhänsli, B. Zolitschka, J. F. W. Negendank, U. Schütz… --- Pages 317-332 / Geochemistry of Lago Grande di Monticchio, S. Italy / C. Robinson, G. B. Shimmield, K. M. Creer --- Pages 333-348 / Tephrochronology of core C from Lago Grande di Monticchio / Anthony J. Newton, Andrew J. Dugmore --- Pages 349-365 / A palaeomagnetic study of maar-lake sediments from the Westeifel / B. Haverkamp, Th. Beuker --- Pages 367-376 / Preliminary 50m palaeomagnetic records from Lac du Bouchet, Haute Loire, France / T. Williams, K. M. Creer, N. Thouveny --- Pages 377-392 / Palaeomagnetic investigations of Lago Grande di Monticchio, southern Italy / Ian Turton --- Pages 393-420 / Late-Glacial/Holocene changes of the climatic and trophic conditions in three Eifel maar lakes, as indicated by faunal remains. I. Cladocera / Wolfgang Hofmann --- Pages 421-433 / Late-glacial/Holocene changes of the climatic and trophic conditions in three Eifel maar lakes, as indicated by faunal remains. II. Chironomidae (Diptera) / Wolfgang Hofmann --- Pages 435-439 / Ostracoda (Crustacea) and trichoptera (Insecta) from Late-and Postglacial sediments of some European maar lakes / Burkhard W. Scharf --- Pages 441-446 / Oligocence dinoflagellate-cysts in Quaternary freshwater sediments of Eifel maars / H. Weiler --- Pages 447-465 / Tertiary maars of the Hocheifel Volcanic Field, Germany / G. Büchel, M. Pirrung --- Pages 467-476 / Some aspects of Cenozoic maar sediments in Europe: the source-rock potential and their exceptionally good fossil preservation / W. Zimmerle --- Pages 477-484 / Palaeoecological implications from the sedimentary record of a subtropical maar lake (Eocene Eckfelder Maar; Germany) / Bernd Zolitschka --- Pages 485-489 / Arthropods from the Eocene Eckfelder Maar (Eifel, Germany) as a source for paleoecological information / H. Lutz --- Pages 491-497 / Flowers from the Middle Eocene of Eckfeld (Eifel, Germany)— First results / H. Frankenhäuser, V. Wilde --- Pages 499-503 / Initial results on the importance of a flora from the Middle Eocene of Eckfeld (Eifel, W.-Germany) / V. Wilde, H. Frankenhäuser --- Pages 505-509 / International Maar Deep Drilling Project (MDDP) a challenge for earth sciences? / Jörg F. W. Negendank, Bernd Zolitschka

Description / Table of Contents: Introduction / Pages 1-32 --- Interpretation using nomograms / Pages 33-47 --- Linear parameters / Pages 49-114 --- Non-linear parameters / Pages 115-173 --- Maximum likelihood and maximum entropy / Pages 175-193 --- Analytic inversion / Pages 195-211 --- Advanced inversion methods / Pages 213-227 --- Error analysis / Pages 229-243 --- Parallel computation in modelling and inversion / Pages 245-255

Description / Table of Contents: PREFACE In recent years, there has been increasing interest from geoscientists in potassic igneous rocks. Academic geoscientists have been interested in their petrogenesis and their potential value in defining the tectonic setting of the terranes into which they were intruded, and exploration geoscientists have become increasingly interested in the association of these rocks with major epithermal gold and porphyry gold-copper deposits. Despite this current interest, there is no comprehensive textbook that deals with these aspects of potassic igneous rocks. This book redresses this situation by elucidating the characteristic features of potassic (high-K) igneous rocks, erecting a hierarchical scheme that allows interpretation of their tectonic setting using whole-rock geochemistry, and investigating their associations with a variety of gold and copper-gold deposits, worldwide. About twothirds of the book is based on a PhD thesis by Dr Daniel MOiler which was produced at the Key Centre for Strategic Mineral Deposits within the Department of Geology and Geophysics at The University of Western Australia under the supervision of Professor David Groves, the late Dr Nick Rock, Professor Eugen Stumpfl, Dr Wayne Taylor, and Dr Brendon Griffin. The remainder of the book was compiled from the literature using the collective experience of the two authors. The book is dedicated to the memory of Dr Rock who initiated the research project but died before its completion...

Description / Table of Contents: PREFACE This book represents the first attempt in three decades to marshall out available information on the regional geology of Africa for advanced undergraduates and beginning graduate students. Geologic education in African universities is severely hampered by the lack of a textbook on African regional geology. This situation is greatly exacerbated by the inability of most African universities to purchase reference books and maintain journal subscriptions. Besides, geologic information about Africa is so widely dispersed that a balanced and comprehensive course content on Africa is beyond the routine preparation of lecture notes by university teachers. Since geology is a universal subject and Africa is one of the largest landmasses on Earth with one of the longest continuous records of Earth history, there is no doubt that geologic education in other parts of the world will benefit from a comprehensive presentation of African geologic case histories. The scope of this text also addresses the need of the professional geologist, who may require some general or background information about an unfamiliar African geologic region or age interval. Africa occupies a central position in the world's mineral raw materials trade. Because of its enormous extent and great geologic age, the diversity and size of Africa's mineral endowment is unparalleled. Africa is the leading source of gold, diamond, uranium, and dominates the world's supply of strategic minerals such as chromium, manganese, cobalt, and platinum. Consequently, African nations from Algeria to Zimbabwe depend solely on mineral exports for economic survival. The geologic factors which govern economic mineral deposits are stressed in this text. The geological history of Africa spans 3.8 billion years, a record that is unique both in duration and continuity. Few other parts of our planet match the plethora of geologic phenomena and processes that are displayed in the African continent. From the various stages of crustal evolution decipherable from the Archean of southern Africa, through the plate tectonics scenarios in the ubiquitous Late Proterozoic-Early Paleozoic Pan-African mobile belts and in the Hercynian and Alpine orogenies of northwest Africa, to the East African Rift Valley, Africa is replete with excellent examples and problems for a course on regional tectonics. Teachers of igneous and metamorphic petrology can hardly ignore Africa's anorogenic magmatism (e.g.. layered ultramafic intrusives such as the Great Dyke and the Bushveld Complex; the Tete gabbro-anorthosite pluton; alkaline complexes; basaltic volcanism), or tantalizing highgrade metamorphic terranes such as the Limpopo belt, the Namaqua mobile belt, and the Mozambique belt. From the extensive Precambrian supracrustal sequences throughout the continent with enormous thicknesses of sedimentary rocks that have hardly been deformed or metamorphosed, to the stratigraphic evolution of Africa's present-day passive continental margin, there is a complete spectrum of facies models upon which to base a course on basin analysis and stratigraphy. To maintain its integrity a course on historical geology anywhere in the world must address the theory of Continental Drift beyond invoking past continuities between West Africa and South America. Past connections between West Africa and eastern North America must equally be explored, so also connections between northeast Africa and Arabia, and the paleogeography of southern Gondwana where Africa occupied centre stage. The Precambrian fossil record, the transitions from reptiles to the earliest mammals and dinosaurs, and the evolution of Man are among Africa's unique contributions to the history of life and the story of organic evolution. Although it lies today in the tropics Africa was the theatre of the Earth's most-spectacular glaciations. Even after the scene of continental glaciation had shifted to the northern continents only lately during the Pleistocene, Africa still witnessed spectacular climatic fluctuations during the Quaternary. Certainly students of archeology and paleoanthropology cannot overlook the Quaternary paleoenvironmental record of the Olduvai Gorge in Tanzania, the Lake Turkana basin in Kenya, the Nile valley, the Sahara, and southern Africa. But since African examples have already been cited in standard geologic textbook, I have often been asked why it has become necessary to revive the idea of a full-length textbook on African geology, 30 years after this idea was abandoned by the geologic community. My simple answer, as already stated, is that the wealth of available geologic information about Africa is so enormous and fascinating, but so diffuse, that an attempt must be made to assemble and pass on this knowledge.

Description / Table of Contents: INTRODUCTION The International Summer School of Theoretical Geodesy on Satellite Altimetry in Geodesy and Oceanography was held in Trieste (Italy) from May 25 to June 6, igg2. It was organized by Prof. R. Rummel of the Delft University of Technology and by Prof. F. Sansò of the Politecnico di Milano and was attended by 63 participants and 7 lecturers from 17 countries. The School was hosted by the International Centre of Theoretical Physics of Trieste. Satellite altimetry provides a lot of data that require more and more sophisticated models in order to be interpreted and exploited. One of the main problems related to the practical treatment of the data can be summarized as follows: oceanographers would like to ask geodesists to compute precise orbits and a precise geoid in order to put into evidence the Sea Surface Topography that can be interpreted as an oceanographic signal related to currents and to several physical parameters; on the other hand, geodesists would like to ask oceanographers to a-priori determine the Sea Surface Topography, in order to be able to extract from the altimeter data the geoid and the orbit errors to be used in the gravity field modelling. The solution to this dilemma can only be found in a cooperative frame. An integrated model to be used for a single-step treatment of altimetry is probably far to be defined, so at present geodesists and oceanographers must cooperate to obtain step-wise and iterative modelling of the gravity field and of the oceanographic phenomena. This is precisely the reason why the school on Satellite Altimetry was organized on an interdisciplinary basis...

Description / Table of Contents: INTRODUCTION While the complex mechanical properties of rocks and soils are studied for quite a while, it is only in the last decades that sound established mathematical models were developed based on accurate experimental data. Some rheological properties of geomaterials as for instance creep, were studied for a long time but the experimental data reported were incomplete and, as a consequence, the models developed have missed either the generality necessary for the solving of engineering problems or some of the major specific mechanical properties possessed by these materials as for instance dilatancy and/or compressibility , long term damage etc. Generally, these very particular empirical models were made for a specific test only and therefore are not appropriate for solving problems involving general loading histories. Let us remind that due to the presence of a great number of cracks and/or pores existing in roks and soils, the mechanical behaviour of geomaterials is quite distinct from that of other materials as for instance metals or plastics. That is why rock and soil rheology has some specific aspects. It must also be mentioned that the solving of various problems of rock and soil mechanics posed by modern technology was not possible by using time-independent models, thus the study and development of rehological models become absolutely necessary. In the last decade or so, very accurate experimantal data became available as a result of the development of experimental techniques and of the growing interest for this field of research in the scientific community. These data, in turn, have made possible the development of genuine models for geomaterials, mainly rheological models, able to describe such properties as creep, dilatancy and/or compressibility during creep, long term damage and failure occurring after various time intervals, slip surface formation etc. Today it is clear that no accurate constitutive equation for rocks can be formulated unless the dilatancy phenomena and the time effects are not included. Another idea is the need of a better description of the concepts of damage and failure of rocks, again using in someway the concepts of irreversible dilatancy or another related notion. In soil rheology it is clear that the scale effect may be taken into consideration in order to obtain a corect information from the routine tests. Also in writing the constitutive equations for soils it is neccessary to take into account the microscopic or local phenomena, because there is a great variety of types of saturated or nonsaturated soils, granular or cohesionless soil etc. The aim of the Euromech Colloquium 196 devoted to Rock and Soil Rheology and therefore that of the present volume too, is to review some of the main results obtained in the last years in this field of research and also to formulate some of the major not yet solved problems which are now under consideration. Exchange of opinions and scientific discussions are quite helpful mainly in those areas where some approaches are controversial and the progress made is quite fast. That is especially true for the rheology of geomaterials, domain of great interest for mining and petroleum engineers, engineering geology, seismology, geophlsics, civil engineering, nuclear and industrial waste storage, geothermal energy storage, caverns for sports, culture, telecommunications, storage of goods and foodstuffs (cold, hot and refrigerated storages), underground oil and natural gas reservoirs etc. Some of the last obtained results are mentioned in the present volume...

Description / Table of Contents: INTRODUCTION Over the past 18 years the author and several colleagues have developed a mathematical model designed to predict the propagation characteristics of acoustic waves in marine sediments. The model is based on the classical work of Maurice Biot who developed a comprehensive theory for the mechanics of porous, deformable media in a series of papers spanning the time period from 1941 to 1973. Since our objective was to develop a practical working model that could be used as a guide in planning and interpreting experimental work, we began with the simplest possible form of the model and added various complexities only as they were needed to explain new variations in the data that were obtained. Thus the number of material parameters that had to be measured or assumed at any stage in the development of the model was kept to a minimum. Since the first version of the model was introduced in 1970, we have published over twenty technical papers covering various stages of its development and many papers have been published by colleagues who have utilized our work in various ways. This monograph is an attempt to summarize the development and use of the model to date. Acoustic waves in ocean sediments may be considered as a limiting case in the more general category of mechanical waves that can propagate in fluid-saturated porous media. The general problem of wave motion in this kind of material has been studied extensively over the past thirty years by engineers, geophysicists and acousticians for a variety of reasons. In some cases, interest is focused on low-frequency waves of rather large amplitude, such as those that arise near the source of an earthquake or near a building housing heavy, vibrating machinery. At other times, the main interest is in waves of low frequency and amplitude that have traversed long distances through the sediment. In still another category, high-frequency waves that are able to resolve thin layering and other fine structural details are of interest in studying near-bottom sediments. Thus the full spread of frequency and amplitude has been studied for geological materials ranging from soft, unconsolidated sediments to rock. Because of the almost limitless combinations of different types of sediment, stratification and structure, accurate mathematical description of the wave field produced by a particular source can be constructed only if accurate descriptions of the acoustic properties of individual components can be specified. These properties depend on the geological history of the sediment deposit, on the frequency content of the wave field and on a number of other factors that depend on the environment in situ. A survey of the literature suggests that there are a number of parameters that play principal roles in controlling the dynamic response of saturated sediments...

Description / Table of Contents: PREFACE It is to-day generally recognized by environmental scientists that the particular behaviour of trace metals in the environment is determined by their specific physico-chemical forms rather than by their total concentration. With the introduction, several years ago, of atomic absorption spectrometry at many laboratories involved in environmental studies, a technique for simple, rapid and cheap determination of total metal concentrations in environmental samples became available. As a consequence, there is a plethora of scientific papers and reports where metal concentrations in the environment are only reported as total concentrations. It appears that the simplicity of making accurate determinations of total metal contents in water, sediment and biological samples has somewhat masked the need for improved knowledge about the various forms of metals occurring in the environment as well as the bioavailahility of these forms. In other words, the need for metal speciation in studies of metals in the environment does not seem to have become obvious to most environmental scientists until relatively recently. As a matter of fact, it was only in the middle of the 1970s that the first systematic attempts were made to obtain information about the various metal species occurring in environmental samples. During the last ten years, however, a revolutionary change of attitude towards the importance of metal speciation has occurred and considerable research effort has been devoted by environmental scientists to measuring the concentrations of biologically important trace metals in surface waters. There is currently an increasing effort to couple the development of chemical analytical techniques to process-related biological problems. Concurrently, a new focus is being imposed on ecological impact studies, that of determining which active trace metal species merit the most intensive research from the standpoint of environmental perturbation. Current efforts are directed towards the development of chemical speciation schemes which can be related directly to measures of bioavailability...

Description / Table of Contents: INTRODUCTION In the context of evolutionary studies, it is the privilege of paleontologists to trace the actual course of evolutionary change over time spans that are adequate for such a slow process. At the same time it is their crux that they can not always hope to do this with the resolution necessary to reveal the causal relationships involved. The Tübingen Sonderforschungsbereich 53, "Palökologie", was primarily geared to study the interrelationships between organisms and environments in the fossil record. As is pointed out in this volume, such an approach will necessarily emphasize the static aspect of this relationship, all the more since this is what we need for the practical purposes of facies recognition. This was clone during a time interval of thirteen years at the level of individual species and taxonomic groups ("Konstruktions-Morphologie"), of characteristic facies complexes ("Fossil-Lagerstätten") and of assemblages ("Fossil- VergeseIlschaftungen") with the aim to recognize general patterns that persist in spite of the historical and evolutionary changes in the biosphere. But as our project came closer to its end, the possible causal relationships between physical and evolutionary changes became more tangible. This trend is expressed by symposia devoted to the biological effects of long term tectonic changes (KULLMANN & SCHÖNENBERG, eds., 1983) and of short term physical events (EINSELE & SEILACHER, eds., 1982). But in retrospect it appears that the time scales of the environmental changes chosen were either too large or too small to reveal the mechanisms of evolutionary response. The present volume is the outcome of a symposium of the projects B 20 ("Bankungsrhythmen in sedimentologischer, ökologischer und diagenetischer Sicht", directed by U. BAYER), D 40 ("Analoge Gehäuse-Aberrationen bei Ammonoideen", directed by J. WIEDMANN) and D 60 ("Substratwechsel im marinen Benthos", directed by A. SEILACHER) in September, 1983. tt addresses environmental changes at time scales large enough to produce more than a local ecological response and short enough to observe evolutionary and/or migratory changes at the species and genus levels. It also focusses on basins which by various degrees of isolation provided suitable sites for "evolutionary experiments", such as lakes and marginal epicontinental basins. In a way, this book is a successor of the previous one on "Cyclic and event stratification" (EINSELE & SEILACHER, eds., 1982). Small scale cycles and events are the 'primitives' of a sedimentary sequence, the lowermost scale from which it can be deciphered. However, medium and long term physical cycles commonly impress sedimentological and lithological trends on the stratigraphic column which are accompanied by faunal replacements and cycles. But since sedimentation is controlled both by physical and biological processes, which are intercorrelated in complicated ways, we also need to decode the stratigraphic text. In this effort, paleontological and sedimentological interpretation must go hand in hand. On the 'megascale' of global sea-level changes faunal and species evolution is triggered by opening and closing of migration pathways, sometimes providing us with malor biostratigraphic boundaries. As it turns out, however, integrated research and the choice of suitable scales do not free us from problems of resolution. Thus our inability to distinguish local speciation from ecophenotypic modification and from immigration in the fossil record excludes definite evolutionary answers even in well studied cases. Nevertheless we hope that this approach opens a fruitful discussion, in which stratigraphy, systematic paleontology and paleoecology will be reconciled in a concerted effort to eventually understand the evolutionary mechanisms of our biosphere.