Scientists who have had the opportunity of being associated with Professor Egon T. Degens, to whom this Festschrift is devoted, have been influenced by his ideas on subjects as varied as: extraterrestrial organic matter, origin of life, evolution of organisms, isotope biogeochemistry down to more imminent ones such as the carbon cycle and its implications on climate. This variety is also reflected in the papers in the present volume contributed by colleagues who have known Egon or have worked with him. Egon Theodor Degens was born on April 16, 1928 at Inden, Germany and had his education in Bonn and Wiirzburg. After a stint at the Pennsylvania State University he returned to Wiirzburg to help set up one of the first organic geochemistry laboratories in the world. This laboratory was the breeding ground for some of the eminent organic geochemists at work today. Later, he joined the California Institute of Technology and began his work on stable carbon isotopes, and later on biogeochemical compounds in natural waters. From California he moved on to the east coast, which led to yet another productive phase at the Woods Hole Oceanographic Institution. He was instrumental in the pioneering work carried out by the Woods Hole scientists in the Black Sea which is the largest anoxic basin in the world, and in the Red Sea where the first hydrothermal ore deposits on the seafloor were discovered.

The fundamental principles of tephrochronology were de- veloped in Iceland through the classic research of Professor Sigurdur Thorarinsson in the 1940's and 1950's. By his studies on the volcanic ash layers (tephra) produced by the historic explosive eruptions of the volcano Hekla, he established that individual tephra layers could be correlated over large areas of Iceland. As the deposition of such layers was essentially instantaneous on a geological time-scale, the tephra layers provided a distinctive and widespread isochronous stratigraphic marker. Since Thorarinsson's pioneering work, the study of tephra has become a powerful and increasingly important research tool in many branches of the geological sciences and related disciplines. In response to the recent rapid growth and diversifica- tion of tephra studies we decided to coordinate a NATO Advanced Studies Institute under the auspices of the INQUA Commission on Tephra. The ASI, entitled "Tephra Studies as a Tool in Quaternary Research," was held from June 18th to June 29th, 1980, at Laugarvatn in Iceland. This book represents the proceedings of that Institute and is the first book dedicated to tephra studies, its many uses and applications. The subject matter combines disciplines as diverse as Quaternary strati- graphy, isotope geochronology, petrology, deep-sea geology, volcanology, volcanic hazards mapping, archaeology and ecology in one volume, and illustrates both present uses and future potential of tephra research.

This collection of papers is based on a symposium held in 1987 at the Interna tional Union of Geology and Geodesy Congress in Vancouver, British Colum bia. The Symposium was planned as a follow-up to a session at the 1984 Geo logical Society of America Annual Meeting in Reno, Nevada, which dealt with the emplacement of silicic lava domes. In both cases, emphasis was placed on the physical and mechanical rather than chemical aspects of lava flow. The IUGG Symposium consisted of two lecture sessions, a poster session, and two discussion periods, and had 22 participants. The contributions to this volume are all based on papers presented in the various parts of the Sym posium. The motivation for studying lava flow mechanics is both practical and scientific. Scientists and government agencies seek to more effectively predict the hazards associated with active lavas. Recovering mineral resources found in lava flows and domes also requires an understanding of their emplacement. From a more theoretical standpoint, petrologists view lava studies as a way to directly observe the rheologic consequences of mixing crystals, bubbles, and solid blocks of country rock with silicate liquids. This information can then be used to constrain processes occurring in the concealed conduits, dikes, and chambers that feed flows and domes on the surface."

This book deals with the problems and methods of paleohydrogeolo gy in relation to ore deposit studies. It presents a description of dif ferent techniques used in the course of structural-paleohydrogeologi cal, paleo hydrogeochemical and paleo hydro geothermal investiga tions. It also provides itlformation on the regular, regional patterns of formation and subsequent distribution of ground water within dif ferent shells of the Earth. The main aspects of metal content of ground water and contemporary processes of ore genesis are discuss ed. Ore deposits are classified according to paleohydrogeological con ditions under which they were formed. The readers are acquainted with paleohydrogeological analysis of these conditions for different types of ore deposits, namely (1) ore deposits formed in artesian basins, in which sedimentary rocks were predominant both at the time of magmatic activity and in the periods free of this activity; (2) ore deposits formed in artesian, ad artesian basins (and admassifs) characterized by extensive development of volcanic rocks and magmatic activity; (3) ore deposits that originated in hydrogeological massifs (and admassifs) in the process of formation of linear weather ing crusts. This book, which should be of great interest to geologists engaged in prospecting for and exploration and study of ore minerals, also in cludes 38 tables, 60 illustrations and a bibliography of 450 titles. EVGENY A. BASKOV Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 The Science of Paleohydrogeology and Its Objectives in Ore Deposit Studies . . . . . . . . . . . . . . . . 4 2 Principal Distribution Patterns of Contemporary Ground Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2. 1 Notion of Hydrosphere . . . . . . . . . . . . . . . . . . . . . . . . ."

At last geochemists are offered one comprehensive reference book which gives the Eh-pH diagrams for 75 elements found in the earth's surface environment, including transuranic and other radioactive species. For each of these newly calculated diagrams short explanatory texts are added. For the first time the primary elements are considered in water with metal, sulfur, carbon, and other species as appropriate. Furthermore, based on these figures and up-to-date thermodynamic data presented in this reference, researchers can predict the behavior of elements in the surface environment. Geoscientists, chemists and environmental agencies will also benefit from several brief texts on the importance of various elements to problems of radioactive waste disposal.

This book originally appeared in German in 1974, under the title "Bergschadenkunde" (mining subsidence engineering), and then in Russian in 1978, published by Nedra of Moscow. When the German edition was almost out of print, Springer-Verlag decided to bring out a new edition, this time in English. For this English version the text has been thoroughly revised, enlarged, and sup plemented by over 100 new figures. The book deals with the current state of international knowl edge on strata and ground movement over mine workings, with its damaging effects on mine shafts and the land surface, and with measures for regulating mining damage in law and reducing it in practice. Discussion begins with the mine excavation underground - the cause - and ends with the damage to surface structure- the effect. Methods of roof control, including the subject of rock bursts, are not discussed, since that is a field concerned more with the safety of underground workings than with minimizing damage at the surface. Of the 500 literature references in the German edi tion, only the more important for an international readership have been retained, but no value judgement on the many pUblica tions not mentioned should be read into this. The book is principally intended as a working aid for the mine surveyor, the mining engineer, the architect, and the civil engineer. For the student and the post-graduate researcher, it of fers a summary and guide to this whole field of knowledge."

During the last thirty years profound developments in expe- rimental techniques to measure high temperature and pressu- res and thermodynamic properties of minerals have occurred. This technical development has been matched by an increased sophistication in applying theoretical methods to obtain new data or improve the quality of existing data. Using these newtechniques, Assessed Thermodynamic Data on Oxides and Silicates represents the successful attempt of the authors to develop an internally systematized data base which satis- fies the constraints of calorimetric measurements, phase equilibrium data, measured thermophysical properties of a phase, and heat capacities and entropies estimated from lat- tice vibrational models.

In these days of information explosion and high-cost publishing, it is perhaps only reasonable for an author to convince the reading public that it is getting something worth reading. After all, intense research into the upper mantle over the past two decades has already resulted in a number of volumes on kim berlites and their xenoliths. So why yet another one? First, in this book I have concentrated on kimberlite as an individual rock-type and a sampler of the upper mantle, in the hope of complementing such monographs as Deep seated inclusions in kimberlites and the problem of the composition of the upper mantle by N. V. Sobolev and Geologie du Diamant by M. G. Bardet, which have concentrated more on specific aspects of kimberlite and upper mantle geology; as a result I have not attempted to describe diamond prospecting and mining and, although I have attempted to give some of the up-to-date views on xenolith petrology, the confines of space have not permitted me to explore the complexities of the upper mantle as deeply as has Sobolev. Second, the literature is vast and I have tried to pull together for the reader the wide range of views and infor mation presented both in the recent geological literature and in recent multi-author volumes such as the Proceedings Vol umes of the two International Conferences on Kimberlite held at Capetown in 1973 and Santa Fe in 1977."

Papers presented at a Symposium held in Utrecht, The Netherlands, October 1982

On February 19, 1973, five centuries have elapsed since the birth of Nicolaus Coperni cus - the greatest astronomer of the Renaissance period - who rediscovered for us the heliocentric model of the solar system, and documented it by his life's work in such a manner as to make its concept a permanent property of mankind. The life of Copernicus, extending from 19 February 1473 to his death on 24 May 1543, was not too rich in adventures or biographical facts. Born in Toruti from a family of Polish burghers, he received his first university training in Cracow between 1491-1494. From Cracow he proceeded to Italy to spend the years between 1496-1503 at the Universities of Bologna, Padua and Ferrara - with occasional visits to Rom- in preparation for an ecclesiastical career. When Bishop Watzenrode - his patron and maternal uncle - could no longer extend his leave, Copernicus returned to Poland in 1503 to enter the service of the church establishment, which soon led to a canonry at the Frombork (Frauenburg) Cathedral in Warmia. And there - in the northern mists not far from the Baltic shores - in a land so different in climate from the sunny Italy of his youth - he was destined to spend the rest of his life."

Basic magmatic rocks make up approximately three-quarters of the crust ofthe present day Earth. Because we can observe and study the volcanic products of present day tectonic regimes comprehensively, we can shed light on ancient tectono-magmatic provinces, and thereby deduce the petrogenesis and evolution of the oldest basic rocks. This is the primary objective of this book. The book was conceived in order to provide a comprehensive review of the basic rocks produced during the first half of the Precambrian, i.e. the Archaean and early Proterozoic, to about 1.8 Ga years ago. Two major questions are addressed. First, what basic magmas were generated during the early Precambrian: were these magmas globally uniform, and to what extent were prevailing tectonic controls and compo sitions analogous to those of the present day? Clearly, this can be answered only by bringing together fundamental information about all relevant basic magmatic events. Second, is there any systematic temporal variation in the nature of basic suites, and what implications might such variations have on our interpretations of early Earth history? Are there important differences between early Archaean, late Archaean, Proterozoic and modern basic magmatic suites? The book uses two approaches to address these questions. Early chapters examine the fundamental characteristics of these basic rocks, whilst later chapters assess regional distribution and development by providing an overview of each major early Precambrian craton."

At first glance it may seem presumptuous to want to add yet another to the numerous books on Differential Thermal Analysis (DT A). Thermoanalytical methods have been in use for some time, as shown by the more than five thousand publications containing DT A or TG curves listed by SMOTHERS and CHIANG in the bibliography to their handbook and abstracted in the several volumes of Thermal Analysis Abstracts (TAA), edited by J. P. REDFERN for the International Con federation for Thermal Analysis (ICT A). Every three years the proceed ings of ICT A meetings are published, bringing the latest results of thermoanalytic research. There is also the Scifax DT A Data Index, edited by R. C. MACKENZIE (1962) and modeled on the ASTM pattern card index (used for X-ray investigations), a compilation of the DT A data for several hundred minerals, and inorganic and organic materials. The theoretical foundations of thermogravimetry and DT A have been described in detail by LEHMANN, DAS and PAETSCH (1953), R. C. MACKENZIE (1957, 1970), DUVAL (1963), WENDLANDT (1964), GARN (1965), F. PAULIK et al. (1966), SMOTHERS and CHIANG (1966), and KEATTCH (1969). Thermoanalytical results are strongly influenced by various factors relative to preparation and equipment (see 1-2. 4 of this study). This is the reason why we frequently find, in these books as well as in the Scifax-Card catalog, contradictory data on the same substance."

1.1. HISTORICAL DEVELOPMENT OF THE OPHIOLITE CONCEPT. Ophiolite, Greek for 'the snake stone', appears to have received its first written definition by Brongniart (1813) as a serpentine matrix containing various minerals. Later in 1821 and 1827, Brongniart determined that volcanic and gabbroic rocks were also present, associated with cherts, and he ascribed an igneous origin to the ophiolite. Amstutz (1980) gives an excellent exegesis of these early contributions and traces the further use of the term and concept of ophiolite. This concept had been forged in the western Alps and Apennines where, thanks to talented Italian geologists, in particular A. Sismonda, B. Gastaldi, V. Novarese and S. Franchi, the study on metamorphic ophiolites (the 'pietre verdi') has rapidly progressed. At the tum of the century the association of radiolarite, diabase, gabbro (euphotide), and serpentinite-peridotite was clearly identified, even through their metamorphic transformations. In 1902, Franchi developed the hypothesis introduced earlier by Lotti (1886), of a submarine outflow to explain the 'pietre verdi' association, on the basis of the attribution of the variolites and metamorphic prasinites to an hypabyssal volcanism, also responsible for the formation of radiolarites. Thus, before the popular work of Steinmann in 1927, the various components constituting an ophiolite had been identified and its hypabyssal origin proposed. As recalled by Amstutz (1980), the so-called 'Steinmann trinity', which consists of the association of radiolarites, diabases and serpentinites, was more completely and better defined in these earlier works.

In the extensive field of earth sciences, with its many subdisciplines, the trans fer of knowledge is primarily established via personal communication, during meetings, by reading journal articles, or by consulting books. Because more information is available than can be assimilated, it is necessary for the individual to search selectively. Books take more time from the inception of an idea until publication than any of the other means of communication men tioned. As a consequence, their function is somewhat different. Many good books are a compilation of up to date knowledge and serve as reference or instruction manuals. Some books are a collection of previously published papers dealing with a certain topic, while others may basically provide large sets of data or examples. The Frontiers in Sedimentary Geology series was established both for stu dents and practicing earth scientists who wish to either stay abreast of the most recent ideas or developments or to become familiar with an important topic in the field of sedimentary geology. The series attempts to deal with sub jects that are in the forefront of both scientific and economic interest. The treatment of a subject in an individual volume should be a combination of topi cal, regional, and interdisciplinary approaches. Although these three terms can be defined separately, in reality they should flow into each other. A topical treatment should relate to a major category of sedimentary geology.

In recent years mineralogy has developed even stronger links with solid-state chemistry and physics and these developments have been accompanied by a trend towards further quantification in the theoretical as well as the experimental aspects of the subject. The importance of solid-state chemistry to mineralogy was reflected in a symposium held at the 1982 Annual Congress of The Royal Society of Chemistry at which the original versions of most of the contributions to this book were presented. The meeting brought together chemists, geologists and mineralogists all of whom were interested in the application of modern spectroscopic techniques to the study of bonding in minerals. The interdisci plinary nature of the symposium enabled a beneficial exchange of information from the various fields and it was felt that a book presenting reviews of the key areas of the subject would be a useful addition to both the chemical and mineralogical literature. The field of study which is commonly termed the 'physics and chemistry of minerals' has itself developed very rapidly over recent years. Such rapid development has resulted in many chemists, geologists, geochemists and mineralogists being less familiar than they might wish with the techniques currently available. Central to this field is an understanding of chemical bonding or 'electronic structure' in minerals which has been developed both theoretically and by the use of spectroscopic techniques."

The Advanced Science Institute on which this publication is based took the somewhat unusual form of a geological field symposium held during late August 1984. It was designed to demonstrate to experienced earth scientists from the North Atlantic area the full range of geological phenomena encountered in the British Caledonian rocks. The ASl travelled from South Wales to the far northwest of Scotland by the route shown on the map and in doing so examined sedimentary, igneous and metamorphic rocks from Pembrokeshire (Dyfed), Cardigan (Ceridigian), Snowdonia, Anglesey, the English Lake District and the Southern Uplands and Highlands of Scotland. Thus the fifty or so participants in the ASl studied the geological history and major structures of rocks exposed on either side of the supposed Lower Palaeozoic Iapetus Ocean the British sector of which closed to the south of the present Southern Uplands. Wales (1-5) afforded insight into the nature of the late Precambrian basement of England and Wales and the relationship of sedimentary and volcanic cover sequences to this basement. The Ordovician sequence in Wales is a sample of the volcanic rocks typical of a marginal basin, and were examined in Pembrokeshire and Snowdonia. The English Lake District (6) displays rocks from an island arc also of Ordovician age.

The fourth volume in this series consists of eleven chapters. The first five deal with more theoretical aspects of the kinetics and mechanisms of meta morphic reactions, and the next six consider the interdependence of defor mation and metamorphism. All papers deal with natural processes that inter act on various time scales and with different degrees of mass and heat transfer. Consequently, many fundamental axioms of metamorphic petrol ogy and structural geology are questioned both for their accuracy and their usefulness. In raising such questions, most contributors have pointed to ways in which the answers could be forthcoming from appropriate experi mental studies or observations on natural materials. In their discussion of how order/disorder can influence mineral assem blages, Carpenter and Putnis emphasize that metastable crystal growth is common in metamorphic systems and state' 'there may be some reluctance (among many earth scientists) to accept that significant departures from equilibrium could occur." On the basis of presented evidence, they question whether reactions ever occur close to an equilibrium boundary. The neces sity for pressure or temperature overstepping is also required by nucleation rate theory. In any case, the degree of order is severely influenced by these kinetic effects in igneous, sedimentary, and metamorphic environments."

Over 60% of the Earth's surface is covered with deep marine sediments, however, until the early 1980s, no comprehensive text books appeared to support the rapid expansion in the study of these sediments. While the whole field of marine geology has expanded enormously and entirely new disciplines, such as paleoceanography, have been developed, there remains a lack of reference texts on study techniques that investigators in the marine community can turn to. Minerals and Mineraloids in Marine Sediments is an optical identifica tion guide that I believe will become a standard reference text for use in the microscope analysis of marine sediment& and sedimentary rocks. The systematic collection of sediment cores from the deep ocean floor began in earnest with the Swedish Deep Sea Expedition, 1947-1948. Much of the microscopic examination of the sediments collected in these piston cores (10 m+ long) was conducted on separated grain mounts or thin sections of impregnated sediments. By the late 1960s a simpler technique of examining a mounted smear of the cored silt and clay size sediment on a microscope slide had become standard practice in American oceanographic institutions. This semi quantitative technique became the standard tool used in core description aboard Glomar Challenger through the 15 years of the Deep Sea Drilling Project (DSDP), 1968-1983. Visual percentage estimates of biogenic and mineral components were made using petrologic micro scopes."

Statistical evaluations of exploration data are the basis for decisions to be made at various stages of an exploration project. In contrast to other geostatistical books, Statistical Evaluations in Exploration for Mineral Deposits focuses not only on theory, but examples are also given, frequently originating from experience in mineral exploration by the author who worked worldwide for a mining company. Together with its companion volume, Economic Evaluations in Exploration, the book illustrates methods used in exploration campaigns and mining activities. It is intended as a vademecum for geologists who are forced to make quick decisions regarding an exploration project. It also addresses scientists and students involved in teaching or in mineral economic evaluations, recommendations or decisions.

This book consists of a collection of papers presented at the NATO Advanced Research Workshop (ARW) on "Crust/mantle Recycl ing at Convergence Zones," held in Antalya, Turkey, between May 25 to 29, 1987. The workshop was attended by 36 earth scientists from ten countries and 28 papers were presented. Crust/mantle recycling is one of the most fundamental processes in the Earth. The study and understanding of this process requires the consideration of the Earth as a whole system including the atmosphere, the hydrosphere and the core, as well as the crust and the mantle; effective interdisciplinary collaboration is therefore essential to our progress. The Antalya ARW gave us the opportunity to assemble key specialists from relevant branches of the earth sciences and to address our state of knowledge. This ARW proved to be very useful in attaining an interdisciplinary, mutual understanding among specialists from diverse fields such as isotope and trace element geochemistry, mineral physics, theoretical geophysics, seismology, experimental petrology, and structural geology.

Acknowledgements xix pioneering workers on igneous layering in Greenland xx Wbrkshop participants xxii Henning Sfl!rensen, University of Copenhagen, Dermark. Latte Melchior Larsen, Geological SUrvey of Greenland, Copenhagen, Dermark. Abstract 1 1 * Introduction 1 1. 1 The agpaitic rocks of the Ilimaussaq intrusion 3 2. Igneous layering in the Ilimaussaq intrusion 4 3. Mineralogy of the layered kakortokite series 15 4. Chemistry of the layered kakortokite series 19 5. Origin of the kakortokite layering 20 5. 1 Discussion 22 6. Conclusion 25 References 26 2. I. AYERn";r CCMPl\CTIOO NID PCBJ. "--MN}tATIC ~ IN '!HE KLOKKEN INTRUSIOO 29 Ian Parsons and SUsanne M. Becker, University of Aberdeen, U. K. Abstract 29 1. Introduction 30 2. Age of the intrusion 31 3. General structure and mineral variation 31 vi TABLE OF CONTENTS 3. 1 Nomenclature of rock types 31 3. 2 Bulk chemical and modal variation 36 4. The contacts and wall-rocks 37 4. 1 Guter contact 37 4. 2 The gabbro sheath 37 4. 3 The unlaminated syenite sheath 39 4. 4 The gabbro-syenite transition 41 5. The layered series 43 5. 1 General relationships 43 5. 2 Granular syenites 43 5. 2. 1 Structure and cryptic variation 43 5. 2. 2 Origin of granular layers 46 5. 2. 3 Trace elements and chamber dlinensions 47 5. 3 Laminated syenites 48 5. 3. 1 General features 48 5. 3. 2 Mineral layering 51 5. 3.

Since the implementation of catalysts containing platinum-group-elements (PGE) for the control of vehicle emissions in 1975, a controversial discussion has begun on PGE emissions and eventual consequences for the environment. However, a comprehensive overview of the various works and results in different scientific areas is still lacking. This book covers all aspects of anthropogenic PGE emissions and their consequences for man and environment. The interdisciplinary approach is substantiated by contributions from the fields of environmental geosciences, analytical chemistry, biology and occupational medicine. The articles mirror the actual status of scientific work and discuss environmentally related topics. Modern analytical methods for various environmental matrices as well as models of the current and future geochemical behaviour of PGE in the environment are presented. Bioavailability and toxicological and allergic potentials are discussed.

We are pleased to present to our readers the proceedings of the Seventh Internat ional Workshop on Phosphate and other Minerals which was held in Marsielle, France during September 1-4, 1985. It was hosted by Professor Michel Olmer, the Chief of the Divison of Nephrology in Hopital de la Conception of the University of D'Aix Marsielle II. The workshop was attended by 250 scientists from 17 countries including Algeria, Austria, Belgium, Canada, Czechoslovakia, Democratic Republic of C'.ermany, Egypt, England, France, Israel, Italy, Japan, Spain, Switzerland and the United States of America. There were 28 invited presentations by leading scientists and 40 oral and 75 poster presentations selected from over 200 abstracts submitted to the Organizing Commi ttee. This meet ing provided an excellent opportuni ty for interested scientists from interrelated disciplines including nephrology, endcrinology, physiology, biochemistry and nutrition to get together and discuss recent advances in the field of phosphate and mineral metabolism."

Everyone is familiar with the daily changes of air temperature. The barometer shows that these are accompanied by daily changes of mass distribution of the atmosphere, and consequently with daily motions of the air. In the tropics the daily pressure change is evident on the barographs; in temperate and higher latitudes it is not noticeable, being overwhelmed by cyclonic and anticyclonic pressure variations. There too, however, the daily change can be found by averaging the variations over many days; and the same process suffices to show that there is a still smaller lunar tide in the atmosphere, first sought by Laplace. Throughout nearly two centuries these 'tides', thermal and gravitational, have been extensively discussed in the periodical literature of science, although they are very minor phenomena at ground level. This monograph summarizes our present knowledge and theoretical under standing of them. It is more than twenty years since the appearance of the one previous monograph on them - by Wilkes - and nearly a decade since they were last comprehensively reviewed, by Siebert. The intervening years have seen many additions to our know ledge of the state of the upper atmosphere, and of the tides there, on the basis of measurements by radio, rockets and satellites.

In its relentless pursuit of further knowledge, science tends to compartmentalize. Over the years the pursuit of What might be called geophysical acoustics of the sea-surface has languished. This has occured even through there are well-developed and active research programs in underwater acoustics, ocean hydrodynamics, cloud and precipitation physics, and ice mechanics - to name a few - as well as a history of engineering expertise built on these scientific fields. It remained to create a convergence, a dialogue across disciplines, of mutual benefit. The central theme of the Lerici workshop, perhaps overly simplified, was 'What are the mechanisms causing ambient noise at the upper surface of the ocean?' What could hydrodynamicists contribute to a better understanding of breaking wave dynamics, bubble production, ocean wave dynamics, or near-surface turbulence for the benefit of the underwater acoustics community? What further insights could fluid dynamicists gain by including acoustic measurements in their repertoire of instrumentation? While every attendee will have his or her percep tions of details, it was universally agreed that a valuable step had been taken to bring together two mature disciplines and that significant co-operative studies would undoubtedly follow. The scope of the workshop was enlarged beyond its original intent to also include the question of ice-noise generation. The success of this decision can be seen in high quality of the presentations. the contribution of its disciples in the other workshop discussions and the heightened awareness and interest of we other novices."