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Award of the V. M. Goldschmidt and F. W. Clarke Medals of the Geochemical Society 9 November 1977, Seattle, Washington
Geochimica
et Cosmochimica
Acta,
1978, Vol. 42, pp. 441 to 447. Pergamon
Press.
Punted
m Great
Britain
Award of the V. M. Goldschmidt and F. W. Clarke Medals of the Geochemical Society 9 November 1977, Seattle, Washington The President-Elect of the Geochemicai Society, Dr. Hugh J. Greenwood, acting as Chairman, called upon President Edwin Roedder to present the awards to the medallists. The speeches of Introduction and Acceptance follow:
Introduction of Samuel Epstein for the V. M. Goldschmidt
Medal
HUGH P. TAYLOR, JR.*
Mr. President, Members of the Geochemical Society, and Guests : It is a distinct pleasure for me to be able to introduce this year’s recipient of the Geochemical Society’s most prestigious award. Previous recipients of the Goldschmidt Medal include Paul Gast, Bob Garrels, Hans Suess, Harold Urey and Hans Eugster. That is distinguished company, indeed, but these high standards are certainly being maintained by the addition of Sam Epstein’s name to the list. Samuel Epstein was born in Poland, but grew up in Winnipeg, Canada. He attended the University of Manitoba and then went to McGill University in Montreal where he received his Ph.D. in chemistry and met his lovely wife Diane. During this period and until the end of the war, he worked on problems of chemical kinetics. selenium, fission products, and the RDX explosives. However, the main focus of his scientific career began when he went to the Ilniversity of Chicago in 1947 to work with Harold Urey. During the next four and one-half years, Sam was right in the center of the group that was responsible for the development of modern stable isotope geochemistry. Even at that early date, his studies of the carbonate paleotemperature scale and of the isotopic variations in natural waters became classics in geochemistry. I only know about this period through conversations with Sam and with other members of that extraordinary group of young scientists who gathered together with Urey and Fermi at the University of Chicago, but I can testify that the excitement of that period continued to be communicated when Sam moved to Caltech in 1952 to set up his own program in isotope geochemistry. I was an undergraduate student at Caltech at this time, and I immediately became intrigued by this field after observing the construction of the new laboratories and after hearing Sam give several lectures on his work. I was so impressed that I came back to Caltech specifically * Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, U.S.A.
to work with Sam, and I have since been fortunate enough to be associated with him either as a collaborator or as a colleague for the past 20 years. I have thus been in a unique position to watch him make one discovery after another, and I have recognized three principal attributes: (1) he focuses directly on the critical aspects of a research problem; (2) he has the laboratory ability to design and carry out remarkably elegant and simple experiments to test his ideas; and (3) he is not afraid to jump into almost any field because he recognizes that he can provide fresh new insights and that it is not always necessary to have an encyclopedic knowledge of a specific discipline in order to make a scientific contribution in that field. Perhaps I might paraphrase Sam’s own advice to a former student as best summarizing his scientific success-“Work only on important and exciting problems, skim the cream, and then move on!” Certainly Sam has the Midas touch: almost everything he touches seems to turn into scientific gold, and the way he practices isotope geochemistry it is a very broad field indeed. He has applied oxygen, carbon, hydrogen and silicon isotope studies to problems of botany, plant and animal physiology, photosynthesis, biochemistry, meteorology, Pleistocene climatology, glaciology, ore deposits, and in many papers on igneous, metamorphic and sedimentary petrology, as well as carrying out important research on the Antarctic and Greenland ice sheets, on isotope geothermometry, on modern geothermal systems, and on the origin of meteorites, tektites and lunar rocks and minerals. At least as important as his own research contributions are the examples Sam has set for the many graduate students and post-doctoral fellows who have worked with him and learned their craft in his laboratory. Sam’s scientific progeny have in turn produced their own students and several of these scientific ‘grandsons’ have returned to work directly with Sam. These progeny have scattered widely and established their own laboratories all over the worfd, from Japan and the Middle East to Western Europe and through-
442
Award of the V. M. Golds~h~idt and F. W. Clarke Medals
out North America. Sam justifiably takes great pride in the success of these younger scientists just as he and Diane do in their own first grandchild, born earlier this year. This has therefore been a memorable year for Sam, because in addition to becoming a grandfather, he was elected to the National Academy of Sciences, and he was able to spend a few months in Israel, where both he and Diane have many attach-
ments. It is truly a fitting climax to cap this year off with today’s presentation. Mr. President, it is difficult for me to put into words the respect and affection I have for this man, who has been so much responsible for my own scientific career. Therefore, it is with pleasure and a deep sense of honor that I present to you my friend and colleague, Samuel Epstein, the 1977 V. M. Goldschmidt Medalist in Geochemistry.
Acceptance Speech for the V. M. G~ldsc~midt
Medal
SAMUEL EPSTEIN* Mr. President, Members of the Geochemical Society and Guests: When I first learned that I was to receive the V. M. Goldschmidt Medal for this year I was greatly surprised and certainly very pleased. As a geochemist, I felt very honored to have been selected as a recipitent of what is to me a most meaningful medal. I was and am very grateful to the Geochemical Society, its Council and Committee who judged me worthy of this honor. I also became more acutely aware of what a privileged individual I am to be able to do fascinating work, make a living at it and even get some side benefits. But most of all I felt a sense of gratitude to so many people, including my wife, Diane, who made it possible for me to do the things I like to do most of all. One of my friends, who shall remain nameless, once accused me of having a very benevolent guardian angel. I am no longer able to deny this allegation as strongly as I have previously. I have been a lucky fellow. When I was a not p~ticularly distinguished undergraduate at the University of Manitoba majoring in chemistry and geology, a research or teaching career was not among my prime ambitions nor realistic objectives. However, when my physical chemistry professor, A. N. Campbell, probably prompted by my guardian angel, offered me the opportunity to do a master’s thesis under his supervision, I accepted, and it was then that I discovered in scientific research a world of such wonders and fascination that until this very day I shudder to think how close I came to missing the opportunity of being part of this fascinating world. My Ph.D. at McGill in Chemistry with C. A. Winkler, and the following few years at the Canadian National Research Council, provided new experiences which served me well in my work in geochemistry. It was during this period of time that I spent a year at McMaster University with H. G. Thode who introduced me to mass spectrometry and it was Harry Thode who arranged for me to come to the University of Chicago to work with Harold C. Urey. * Division of Geological and Planetary Sciences, California Institute of TechnoIogy, Pasadena, CA 91125, U.S.A.
I spent four and one-half years in Urey’s laboratory and it was there that my career as a stable isotope geochemist was shaped and the influence of Harold Urey and my other colleagures indelibly marked my scientific work. It was also there that many important beginnings were made in several branches of the geosciences. My move to Caltech was entirely due to a chance meeting with Harrison Brown in one of the halls of the Enrico Fermi Institute for Nuclear Studies, It was about that time that Harrison Brown decided to join the Caltech Geology Division, which was planning to expand and include geochemistry among its activities. It was invited to come aboard and become a member of this division and I accepted. Within a short period of time I intuitively felt that at Caltech I had finally found my permanent home. My hunch proved right. I have now been at Caltech over twentylive years. The incorporation of a successful stable isotope research program in our Division of PIanetary and Geological Sciences was made possible by many factors, among which the more important ones were the enlightened attitude towards innovation of my first chairman, Robert P. Sharp, the community of outstanding scholars in our division and at Caltech as a whole and, of course, the important ingredient, excellent students. My loyalty to stable isotope geochemistry throughout these years stems mainly from the great diversity of interests that working in this field allows. Just think for a minute the various roles that oxygen, carbon and hydrogen isotope measurements play just in the fields related to the geosciences. The isotopic methods of measuring temperatures allowed geoscientists to reconstruct the temperature of the oceans for the past 120 million year history of the Earth, to within kl”C. The isotopic method also contributed importantly to the unravelling of the detailed Holocene temperature record of the oceans. Recent work showed that the hydrogen and oxygen isotopes in tree rings and plants also provide information about the climatic history of the continental surface of the Earth over the past thousands of years, and there is even a possibility that the isotopic measurements of cherts may provide some ideas of what the
443
BJC~RNMYSEW
444
SAMUEL
EPSTEIN
Award
of the V. M. Goldschmidt
temperatures were like as far back as three and onehalf billion years ago. Isotope measurements have made con~ibutions to glaciology, to paleontology, to understanding of the magnitude of rock-water interaction. They gave information about the origin of ore deposits and contributed significantly to ground water hydrology, as well as to problems of physical oceanography. Geobiology also benefited from isotopic investigations contributing to studies on the origin of petroleum, as well as on the origin of some very ancient carbon compounds. Isotopic work has been extended to include investigations of lunar samples as we11as meteorites. The cooperation of colleagues like R. P. Sharp, H. P. Taylor, H. A. Lowenstam and L. T. Silver allowed me, personally, to contribute to some of these fields of investigation. However, most of the stable isotope research that has been done in my laboratory was carried out by young scientists who have spent some
and F. W. Clarke
Medals
445
time there either as graduate students or post doctoral fellows. To this very day one of the greatest satisfaction I derive from my career is the feeling that I might have contributed in some way to the careers of these young scientists. The award that I receive today, I interpret as being mainly a recognition of the fundamental contributions that many people in the field of stable isotope geochemistry have made to the understanding of a wide spectrum of geological processes. I anticipate that recognition of these contributions by the geology community as a whole will increase, and result in the well-deserved recognition of other stable isotope geochemists. I am flattered to have my name added to the list of such distinguished former recipients of the Goldschmidt Medal. Thank you again for the honor you have bestowed upon me, and for creating such an important highlight in my life.
Introduction of Bj$rn 0. Mysen for the F. W. Clarke Medal DAVID H. EGGLER*
Mr. President, Members of the Geochemical Society, and Guests: In the fall of 1972, I arrived at the Geophysical Laboratory, eager to learn the effects of CO, and H,O upon phase relations in peridotite systems. I had no sooner walked in the door than I heard rumors of the impending arrival of a Postdoctoral Fellow from Penn State, reputed to be a superstar graduate student and reputed to be working on peridotite H,O-CO2 relations at high pressures. Now I confess that I usually feel vaguely uneasy in the presence of superstars, and I also feel uneasy about investigating a topic that I know is being investigated elsewhere, despite a conviction that in the end science is usually the winner. Upon meeting Bjorn Mysen, however, these feelings were quickly forgotten. It turned out that he was indeed a prime candidate for a high-pressure star--stimulating, hard working, inventive-but at the same time was a comfortably low-pressure person. Moreover, it turned out that our courses of research were complementary, leading to many cooperative projects in the next five years. Bjorn Mysen took his early geologic training in his native land of Norway, receiving the degrees B.Sc. and M.A. at the University of Oslo. The subject of his M.A. thesis, directed by Professor Knut Heier, was Norwegian eclogites, also the subject of seven papers of which he was author or co-author. In 1972 he arrived at The Pennsylvania State University. Working with Professor A. L. Boettcher, he instantly became an experimental petrologist, moving at a furi* Department of Geosciences, University,
University
Park,
The Pennsylvania PA 16802, U.S.A.
State
ous pace through the study (~orementioned) on the melting relations of peridotite at high pressures in the presence of COZ and HrO. Later in 1972 he came to Washington, DC and the Geophysical Laboratory to continue that project as a Predoctoral Fellow. He achieved a certain amount of notoriety during that period for the quickness with which he negotiated weekly return visits to the Penn State campus, quickness inspired at least in part, one supposes, by the presence in Washington of the young woman who is now his wife. After receiving the Ph.D. degree from Penn State in 1974, he remained at the Geophysical Laboratory as a Postdoctoral Fellow, becoming a permanent statf member in 1977. In the 1972-1977 period he was author or co-author of 42 papers in experimental petrology. As student and Fellow, Bjerrn has been uncommon in his comprehension and initiative. Such initiative propelled him and M. G. Seitz in 1973 to develop quantitative autoradiographic (P-track mapping) techniques in experimental petrology. These techniques have become the leading method for trace element analysis of phases in experimental charges. Bjern has applied the techniques to determination of the CO, solubility of silicate liquids (with mysdf and J. R. Holloway), to determination of degrees of melting in experimental runs (with I. Kushiro) and, more recently, to determination of partition coefficients of nickel and rare earth elements between silicate liquids and crystals. He is being honored today for the paper The role of volatiles in silicate melts: sofubility of carbon dioxide and water in feldspar, pyroxene and fe~dspat~oida1 meits to 30 kbar and 1625”C, in which he deter-
mined combined CO, and H,O solubilities, using r4C
Award of the V. M. Goldschmidt and F. W. Clarke Medals
446
and 3H, in three melts on the join NaA1Si04-Si02 as functions of pressure, temperature and volatile content; he also determined the species in solution by infrared spectrometry. He then could relate solubility differences to changes in polymerization and in coordination of the aluminium cation. This paper is an illustration of his application of novel techniques to basic problems of silicate geochemistry. His past achievements notwithstanding, I anticipate that Bjorn’s chief contributions are ahead of him.
Recall that he began a career in experimental petrology but five years ago and now provides leadership at the place where experimental petroiogy was born. Ever-stimulating occasionally controversial, he will continue to pursue, and reveal, critical problems in geochemistry. It is indeed a pleasure for me to introduce Bjorn 0. Mysen, the 1977 recipient of the F. W. Clarke Medal of the Geochemical Society.
Acceptance Speech for the F. W. Clarke Medal BJ#RN Although awards are generally presented to individuals, they often reflect the result of team work. My case is no exception, and I would, therefore, rather thank you on behalf of all those people that I have been fortunate enough to be associated with than simply for myself. It is customary to mention all those to whom a recipient is grateful. I do not have the time to mention them all so let me just mention that without David Eggler, who just presented me with the medal, I would not stand here today. The work on C02-solubility in silicate melts at high pressures and temperatures is as much the result of David Eggler’s interest and work as my own. On occasions like this one tends to reflect on how it all started. I have heard a variety of stories about how CO2 came to be appreciated as an important component in magmatic processes. David Eggler once said that he watched CO, bubbles being released from beer and decided that carbon dioxide may also be important in magma genesis. I guess my involvement came from melting of peridotite in the presence of Hz0 and CO2 with the assumption that CO2 could be considered an inert component with respect to the silicates. It became evident that the assumption did not hold, and we began worrying about rapid methods of determining volatile contents of melts. At that time 1 was fortunate enough to be associated with Martin Seitz, who was intimately familiar with the use of radioactive tracer technology. The cooperation with him led to the development of the technique that was subsequently used to determine not only CO2 contents, but also contents of H20, SO2 and various trace elements in a variety of phases, both liquids and crystals. * Geophysical Upton
Laboratory,
St. N.W., Washington,
Carnegie Institution, DC 20008, U.S.A.
2801
MYSEN* As some of you may be aware, it was found that CO,-solubility depends strongly on the bulk composition of silicate melts in addition to pressure and temperature, This dependence relates to the stabilization of carbonate in silicate melt solution. Formation of carbonate anions involve interaction between CO2 and non-bridging oxygens in the silicate network of the melt. Thus, to some extent CO2 solubility data also provide information on the melt structure itself. The formation of carbonate in silicate melt solution is also reflected in the effect of CO, on the melting relations of silicates. Because stabilization of CO:involves lowering of the number of non-bridging oxygens in the melt, the melt in effect becomes more polymerized as carbon dioxide is dissolved. A consequence of this interpretation is the enhanced stability of more polymerized silicate minerals in equilibrium with CO,-bearing melts relative to melting and crystallization under CO,-absent conditions. These interpretations, based on CO,-solubility data, have been shown to be consistent with the pioneering phase equilibrium measurements involving carbon dioxide by David Eggler, for example. Those of us who have been, and still are, involved with the role of volatiles in the formation and evolution of magmas feel that these data may be useful in understanding igneous processes. It is sometimes difficult, however, to place the work in perspective when one is as intimately involved with volatiles and their roles in silicate melts as I have been for the last few years. Sometimes it seems that the volatile solubility modelling becomes a goal in itself, which it probably should not be because we call ourselves geochemists and petrologists. I am very grateful to the Geochemical Society, therefore, for the decision to honor us with the I?. W. Clarke medal for 1977, thus making us realize that our work is appreciated.
et Cosmochimica
Acta,
1978, Vol. 42, pp. 441 to 447. Pergamon
Press.
Punted
m Great
Britain
Award of the V. M. Goldschmidt and F. W. Clarke Medals of the Geochemical Society 9 November 1977, Seattle, Washington The President-Elect of the Geochemicai Society, Dr. Hugh J. Greenwood, acting as Chairman, called upon President Edwin Roedder to present the awards to the medallists. The speeches of Introduction and Acceptance follow:
Introduction of Samuel Epstein for the V. M. Goldschmidt
Medal
HUGH P. TAYLOR, JR.*
Mr. President, Members of the Geochemical Society, and Guests : It is a distinct pleasure for me to be able to introduce this year’s recipient of the Geochemical Society’s most prestigious award. Previous recipients of the Goldschmidt Medal include Paul Gast, Bob Garrels, Hans Suess, Harold Urey and Hans Eugster. That is distinguished company, indeed, but these high standards are certainly being maintained by the addition of Sam Epstein’s name to the list. Samuel Epstein was born in Poland, but grew up in Winnipeg, Canada. He attended the University of Manitoba and then went to McGill University in Montreal where he received his Ph.D. in chemistry and met his lovely wife Diane. During this period and until the end of the war, he worked on problems of chemical kinetics. selenium, fission products, and the RDX explosives. However, the main focus of his scientific career began when he went to the Ilniversity of Chicago in 1947 to work with Harold Urey. During the next four and one-half years, Sam was right in the center of the group that was responsible for the development of modern stable isotope geochemistry. Even at that early date, his studies of the carbonate paleotemperature scale and of the isotopic variations in natural waters became classics in geochemistry. I only know about this period through conversations with Sam and with other members of that extraordinary group of young scientists who gathered together with Urey and Fermi at the University of Chicago, but I can testify that the excitement of that period continued to be communicated when Sam moved to Caltech in 1952 to set up his own program in isotope geochemistry. I was an undergraduate student at Caltech at this time, and I immediately became intrigued by this field after observing the construction of the new laboratories and after hearing Sam give several lectures on his work. I was so impressed that I came back to Caltech specifically * Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, U.S.A.
to work with Sam, and I have since been fortunate enough to be associated with him either as a collaborator or as a colleague for the past 20 years. I have thus been in a unique position to watch him make one discovery after another, and I have recognized three principal attributes: (1) he focuses directly on the critical aspects of a research problem; (2) he has the laboratory ability to design and carry out remarkably elegant and simple experiments to test his ideas; and (3) he is not afraid to jump into almost any field because he recognizes that he can provide fresh new insights and that it is not always necessary to have an encyclopedic knowledge of a specific discipline in order to make a scientific contribution in that field. Perhaps I might paraphrase Sam’s own advice to a former student as best summarizing his scientific success-“Work only on important and exciting problems, skim the cream, and then move on!” Certainly Sam has the Midas touch: almost everything he touches seems to turn into scientific gold, and the way he practices isotope geochemistry it is a very broad field indeed. He has applied oxygen, carbon, hydrogen and silicon isotope studies to problems of botany, plant and animal physiology, photosynthesis, biochemistry, meteorology, Pleistocene climatology, glaciology, ore deposits, and in many papers on igneous, metamorphic and sedimentary petrology, as well as carrying out important research on the Antarctic and Greenland ice sheets, on isotope geothermometry, on modern geothermal systems, and on the origin of meteorites, tektites and lunar rocks and minerals. At least as important as his own research contributions are the examples Sam has set for the many graduate students and post-doctoral fellows who have worked with him and learned their craft in his laboratory. Sam’s scientific progeny have in turn produced their own students and several of these scientific ‘grandsons’ have returned to work directly with Sam. These progeny have scattered widely and established their own laboratories all over the worfd, from Japan and the Middle East to Western Europe and through-
442
Award of the V. M. Golds~h~idt and F. W. Clarke Medals
out North America. Sam justifiably takes great pride in the success of these younger scientists just as he and Diane do in their own first grandchild, born earlier this year. This has therefore been a memorable year for Sam, because in addition to becoming a grandfather, he was elected to the National Academy of Sciences, and he was able to spend a few months in Israel, where both he and Diane have many attach-
ments. It is truly a fitting climax to cap this year off with today’s presentation. Mr. President, it is difficult for me to put into words the respect and affection I have for this man, who has been so much responsible for my own scientific career. Therefore, it is with pleasure and a deep sense of honor that I present to you my friend and colleague, Samuel Epstein, the 1977 V. M. Goldschmidt Medalist in Geochemistry.
Acceptance Speech for the V. M. G~ldsc~midt
Medal
SAMUEL EPSTEIN* Mr. President, Members of the Geochemical Society and Guests: When I first learned that I was to receive the V. M. Goldschmidt Medal for this year I was greatly surprised and certainly very pleased. As a geochemist, I felt very honored to have been selected as a recipitent of what is to me a most meaningful medal. I was and am very grateful to the Geochemical Society, its Council and Committee who judged me worthy of this honor. I also became more acutely aware of what a privileged individual I am to be able to do fascinating work, make a living at it and even get some side benefits. But most of all I felt a sense of gratitude to so many people, including my wife, Diane, who made it possible for me to do the things I like to do most of all. One of my friends, who shall remain nameless, once accused me of having a very benevolent guardian angel. I am no longer able to deny this allegation as strongly as I have previously. I have been a lucky fellow. When I was a not p~ticularly distinguished undergraduate at the University of Manitoba majoring in chemistry and geology, a research or teaching career was not among my prime ambitions nor realistic objectives. However, when my physical chemistry professor, A. N. Campbell, probably prompted by my guardian angel, offered me the opportunity to do a master’s thesis under his supervision, I accepted, and it was then that I discovered in scientific research a world of such wonders and fascination that until this very day I shudder to think how close I came to missing the opportunity of being part of this fascinating world. My Ph.D. at McGill in Chemistry with C. A. Winkler, and the following few years at the Canadian National Research Council, provided new experiences which served me well in my work in geochemistry. It was during this period of time that I spent a year at McMaster University with H. G. Thode who introduced me to mass spectrometry and it was Harry Thode who arranged for me to come to the University of Chicago to work with Harold C. Urey. * Division of Geological and Planetary Sciences, California Institute of TechnoIogy, Pasadena, CA 91125, U.S.A.
I spent four and one-half years in Urey’s laboratory and it was there that my career as a stable isotope geochemist was shaped and the influence of Harold Urey and my other colleagures indelibly marked my scientific work. It was also there that many important beginnings were made in several branches of the geosciences. My move to Caltech was entirely due to a chance meeting with Harrison Brown in one of the halls of the Enrico Fermi Institute for Nuclear Studies, It was about that time that Harrison Brown decided to join the Caltech Geology Division, which was planning to expand and include geochemistry among its activities. It was invited to come aboard and become a member of this division and I accepted. Within a short period of time I intuitively felt that at Caltech I had finally found my permanent home. My hunch proved right. I have now been at Caltech over twentylive years. The incorporation of a successful stable isotope research program in our Division of PIanetary and Geological Sciences was made possible by many factors, among which the more important ones were the enlightened attitude towards innovation of my first chairman, Robert P. Sharp, the community of outstanding scholars in our division and at Caltech as a whole and, of course, the important ingredient, excellent students. My loyalty to stable isotope geochemistry throughout these years stems mainly from the great diversity of interests that working in this field allows. Just think for a minute the various roles that oxygen, carbon and hydrogen isotope measurements play just in the fields related to the geosciences. The isotopic methods of measuring temperatures allowed geoscientists to reconstruct the temperature of the oceans for the past 120 million year history of the Earth, to within kl”C. The isotopic method also contributed importantly to the unravelling of the detailed Holocene temperature record of the oceans. Recent work showed that the hydrogen and oxygen isotopes in tree rings and plants also provide information about the climatic history of the continental surface of the Earth over the past thousands of years, and there is even a possibility that the isotopic measurements of cherts may provide some ideas of what the
443
BJC~RNMYSEW
444
SAMUEL
EPSTEIN
Award
of the V. M. Goldschmidt
temperatures were like as far back as three and onehalf billion years ago. Isotope measurements have made con~ibutions to glaciology, to paleontology, to understanding of the magnitude of rock-water interaction. They gave information about the origin of ore deposits and contributed significantly to ground water hydrology, as well as to problems of physical oceanography. Geobiology also benefited from isotopic investigations contributing to studies on the origin of petroleum, as well as on the origin of some very ancient carbon compounds. Isotopic work has been extended to include investigations of lunar samples as we11as meteorites. The cooperation of colleagues like R. P. Sharp, H. P. Taylor, H. A. Lowenstam and L. T. Silver allowed me, personally, to contribute to some of these fields of investigation. However, most of the stable isotope research that has been done in my laboratory was carried out by young scientists who have spent some
and F. W. Clarke
Medals
445
time there either as graduate students or post doctoral fellows. To this very day one of the greatest satisfaction I derive from my career is the feeling that I might have contributed in some way to the careers of these young scientists. The award that I receive today, I interpret as being mainly a recognition of the fundamental contributions that many people in the field of stable isotope geochemistry have made to the understanding of a wide spectrum of geological processes. I anticipate that recognition of these contributions by the geology community as a whole will increase, and result in the well-deserved recognition of other stable isotope geochemists. I am flattered to have my name added to the list of such distinguished former recipients of the Goldschmidt Medal. Thank you again for the honor you have bestowed upon me, and for creating such an important highlight in my life.
Introduction of Bj$rn 0. Mysen for the F. W. Clarke Medal DAVID H. EGGLER*
Mr. President, Members of the Geochemical Society, and Guests: In the fall of 1972, I arrived at the Geophysical Laboratory, eager to learn the effects of CO, and H,O upon phase relations in peridotite systems. I had no sooner walked in the door than I heard rumors of the impending arrival of a Postdoctoral Fellow from Penn State, reputed to be a superstar graduate student and reputed to be working on peridotite H,O-CO2 relations at high pressures. Now I confess that I usually feel vaguely uneasy in the presence of superstars, and I also feel uneasy about investigating a topic that I know is being investigated elsewhere, despite a conviction that in the end science is usually the winner. Upon meeting Bjorn Mysen, however, these feelings were quickly forgotten. It turned out that he was indeed a prime candidate for a high-pressure star--stimulating, hard working, inventive-but at the same time was a comfortably low-pressure person. Moreover, it turned out that our courses of research were complementary, leading to many cooperative projects in the next five years. Bjorn Mysen took his early geologic training in his native land of Norway, receiving the degrees B.Sc. and M.A. at the University of Oslo. The subject of his M.A. thesis, directed by Professor Knut Heier, was Norwegian eclogites, also the subject of seven papers of which he was author or co-author. In 1972 he arrived at The Pennsylvania State University. Working with Professor A. L. Boettcher, he instantly became an experimental petrologist, moving at a furi* Department of Geosciences, University,
University
Park,
The Pennsylvania PA 16802, U.S.A.
State
ous pace through the study (~orementioned) on the melting relations of peridotite at high pressures in the presence of COZ and HrO. Later in 1972 he came to Washington, DC and the Geophysical Laboratory to continue that project as a Predoctoral Fellow. He achieved a certain amount of notoriety during that period for the quickness with which he negotiated weekly return visits to the Penn State campus, quickness inspired at least in part, one supposes, by the presence in Washington of the young woman who is now his wife. After receiving the Ph.D. degree from Penn State in 1974, he remained at the Geophysical Laboratory as a Postdoctoral Fellow, becoming a permanent statf member in 1977. In the 1972-1977 period he was author or co-author of 42 papers in experimental petrology. As student and Fellow, Bjerrn has been uncommon in his comprehension and initiative. Such initiative propelled him and M. G. Seitz in 1973 to develop quantitative autoradiographic (P-track mapping) techniques in experimental petrology. These techniques have become the leading method for trace element analysis of phases in experimental charges. Bjern has applied the techniques to determination of the CO, solubility of silicate liquids (with mysdf and J. R. Holloway), to determination of degrees of melting in experimental runs (with I. Kushiro) and, more recently, to determination of partition coefficients of nickel and rare earth elements between silicate liquids and crystals. He is being honored today for the paper The role of volatiles in silicate melts: sofubility of carbon dioxide and water in feldspar, pyroxene and fe~dspat~oida1 meits to 30 kbar and 1625”C, in which he deter-
mined combined CO, and H,O solubilities, using r4C
Award of the V. M. Goldschmidt and F. W. Clarke Medals
446
and 3H, in three melts on the join NaA1Si04-Si02 as functions of pressure, temperature and volatile content; he also determined the species in solution by infrared spectrometry. He then could relate solubility differences to changes in polymerization and in coordination of the aluminium cation. This paper is an illustration of his application of novel techniques to basic problems of silicate geochemistry. His past achievements notwithstanding, I anticipate that Bjorn’s chief contributions are ahead of him.
Recall that he began a career in experimental petrology but five years ago and now provides leadership at the place where experimental petroiogy was born. Ever-stimulating occasionally controversial, he will continue to pursue, and reveal, critical problems in geochemistry. It is indeed a pleasure for me to introduce Bjorn 0. Mysen, the 1977 recipient of the F. W. Clarke Medal of the Geochemical Society.
Acceptance Speech for the F. W. Clarke Medal BJ#RN Although awards are generally presented to individuals, they often reflect the result of team work. My case is no exception, and I would, therefore, rather thank you on behalf of all those people that I have been fortunate enough to be associated with than simply for myself. It is customary to mention all those to whom a recipient is grateful. I do not have the time to mention them all so let me just mention that without David Eggler, who just presented me with the medal, I would not stand here today. The work on C02-solubility in silicate melts at high pressures and temperatures is as much the result of David Eggler’s interest and work as my own. On occasions like this one tends to reflect on how it all started. I have heard a variety of stories about how CO2 came to be appreciated as an important component in magmatic processes. David Eggler once said that he watched CO, bubbles being released from beer and decided that carbon dioxide may also be important in magma genesis. I guess my involvement came from melting of peridotite in the presence of Hz0 and CO2 with the assumption that CO2 could be considered an inert component with respect to the silicates. It became evident that the assumption did not hold, and we began worrying about rapid methods of determining volatile contents of melts. At that time 1 was fortunate enough to be associated with Martin Seitz, who was intimately familiar with the use of radioactive tracer technology. The cooperation with him led to the development of the technique that was subsequently used to determine not only CO2 contents, but also contents of H20, SO2 and various trace elements in a variety of phases, both liquids and crystals. * Geophysical Upton
Laboratory,
St. N.W., Washington,
Carnegie Institution, DC 20008, U.S.A.
2801
MYSEN* As some of you may be aware, it was found that CO,-solubility depends strongly on the bulk composition of silicate melts in addition to pressure and temperature, This dependence relates to the stabilization of carbonate in silicate melt solution. Formation of carbonate anions involve interaction between CO2 and non-bridging oxygens in the silicate network of the melt. Thus, to some extent CO2 solubility data also provide information on the melt structure itself. The formation of carbonate in silicate melt solution is also reflected in the effect of CO, on the melting relations of silicates. Because stabilization of CO:involves lowering of the number of non-bridging oxygens in the melt, the melt in effect becomes more polymerized as carbon dioxide is dissolved. A consequence of this interpretation is the enhanced stability of more polymerized silicate minerals in equilibrium with CO,-bearing melts relative to melting and crystallization under CO,-absent conditions. These interpretations, based on CO,-solubility data, have been shown to be consistent with the pioneering phase equilibrium measurements involving carbon dioxide by David Eggler, for example. Those of us who have been, and still are, involved with the role of volatiles in the formation and evolution of magmas feel that these data may be useful in understanding igneous processes. It is sometimes difficult, however, to place the work in perspective when one is as intimately involved with volatiles and their roles in silicate melts as I have been for the last few years. Sometimes it seems that the volatile solubility modelling becomes a goal in itself, which it probably should not be because we call ourselves geochemists and petrologists. I am very grateful to the Geochemical Society, therefore, for the decision to honor us with the I?. W. Clarke medal for 1977, thus making us realize that our work is appreciated.