From Mantle to Meteorites

FROM MANTLE TO METEORITES A Garland of Perspectives FESTSCHRIFT FOR DEVENDRA LAL Edited by K. Gopalan, Vinod K. Gaur B.L.K. Somayajulu and J.D. Macdougall » FROM MANTLE TO METEORITES A Garland of Perspectives A Festschrift for Devendra Lai FROM MANTLE TO METEORITES A Garland of Perspectives A Festschrift for Devendra Lai Edited by K GOPALAN V K GAUR BLK SOMAYAJULU J D MACDOUGALL Indian Academy of Sciences Bangalore Published by Indian Academy of Sciences P.B. No. 8005 * C V Raman Avenue Bangalore 560 080 Telephone: 34 25 46 Telex: 0845-2178 ACAD IN Distributed by Oxford University Press YMCA Library Building, Jai Singh Road, New Delhi 110 001 Bombay Calcutta Madras Oxford New York Toronto Melbourne Tokyo Hong Kong ISBN 0-19562581-1 Copyright © 1990 by the Indian Academy of Sciences Typeset at Thomson Press, New Delhi and printed by Macmillan India Press, Madras. CONTENTS Introduction. A friendship with Lai.P B Price Geophysical searches for new forces in nature.Ramanath Cowsik Electrodynamic control in planetesimal accretion.. .DA Mendis and G Arrhenius New quantum chemical isotope effects: Applications to the pre-solar nebula, planetary atmospheres and interstellar space. .Mark H Thiemens and S K Bhattacharya Cosmogenic and radiogenic nuclides: What can we do with a few atoms? .James R Arnold The Earth as a physical laboratory.Helmut Moritz A trial of static Fourier transform mass spectroscopy of xenon. .P McConville and J H Reynolds Multidisciplinary investigations of new collections of Greenland and Antarctica micrometeorites. .Michel Maurette, Claus Hammer and Michel Pourchet Cyclic behaviour of the solar-terrestrial system.G Cini Castagnoli The turbulence of geophysical time.Bruce A Bolt The parameters controlling planetary degassing based on 40Ar systematics .Karl K Turekian Rare gases and hydrogen in native metals. .R J Poreda, K Marti and H Craig Emanation of radon from rock minerals.Rama Several considerations on the early history of the Earth ...EM Galimov Life on the early Earth: Bridgehead from Cosmos or autochthonous pheno¬ menon?.Manfred Schidlowski Factors controlling the distribution of 10Be and 9Be in the ocean. .Tsung-Hung Peng, Teh-Lung Ku, John Southon, C Measures and W S Broecker 201 Asymptotes of coastal upwelling.P K Das and A P Dube 205 Hydrogeology. A new focus .T N Narasimhan 2i3 Geomagnetic paleointensity from quaternary sediments: Methodology, results and future prospects.Subir K Banerjee 229 Steps toward understanding the Earth's dynamic interior. .Peter J Wyllie 239 Application of diamond-anvil-cell technique to study /element metals and some materials relevant to planetary interiors.Jagannadham Akella 249 Applications of Raman spectroscopy in earth and planetary sciences. .Shiv K Sharma 263 Subject index... 309 Author index. 314 List of Publications of D Lai Digitized by the Internet Archive in 2018 with funding from Public.Resource.Org https://archive.org/details/frommantletometeOOunse Devendra Lai INTRODUCTION For a physicist, the best chemist there is In the above words, did Professor J R Arnold describe Devendra Lai, his friend and colleague of many years, on the occasion of Lai’s election as a Foreign Associate of the US National Academy of Sciences. Indeed, there are many qualities responsible for Lai's distinguished scientific career spread over nearly four decades. Even a casual acquaintance wiil not fail to notice his obvious genetic endowments: a questing mind, tenacity of purpose and infinite energy. But his real strength stems from what has been so incisively summed up by Professor Arnold. Professor Lai combines a deep understanding of the physics of high energy particle interactions with a rare insight into the evolution of the tenuous trails which they leave behind in naturally occurring chemical systems. Thus, by tracking down the exotic products of these high energy interactions into the specific niches of various low energy chemical reservoirs, he has made pioneering contributions to such diverse fields as astrophysics, planetary evolution, oceanography -and archaeology. This volume contributed by his colleagues and admirers is presented as a tribute to this versatile and evergreen scientist on the occasion of his sixtieth birthday. Devendra Lai was born in the ancient city of Varanasi (Banaras) on 14 February 1929. He was educated in the same city, receiving his Masters Degree in Physics in 1949 from Banaras Hindu University. With the overwhelming appeal of high energy physics to bright young physicists in those days, the young Lai naturally gravitated to the then newly established national centre for such studies, the Tata Institute of Fundamental Research in Bombay. Here, he began his research career under the stimulating guidance of Prof. Bernard Peters, studying high energy cosmic ray interactions through their tracks recorded in nuclear emulsion plates. Even in the very early years of his research in this highly competitive field, Lai made some very important discoveries such as the associated production of K-mesons and negative K-mesons. Prompted perhaps by the new and important discovery by Prof. W F Libby of cosmic ray-produced C-14 in the atmosphere, Lai, following the suggestion of Professor Peters, began to look for the presence of cosmic ray-produced Be-10 in ocean sediments. Since this isotope has a long life of 1 -5 million years, its variation with depth in these sediments could be used to reconstruct the history of cosmic radiation in the near earth environment over this scale of time. Realizing the far- reaching significance of these investigations in tracing the evolution of various earth processes, Lai took perhaps the most crucial decision in his professional life—to switch from what he could do for cosmic rays to what he could do with them. His marriage at this time with a charming and gracious young lady, Aruna, was a happy coincidence. As Professor Price recalls in the following article, Aruna’s emotional and intellectual identification with Lai’s scientific interests contributed in no small measure to his scientific achievements. ix 1 X Introduction The chemical isolation of Be-10 from ocean sediments and detection of its extremely weak beta radioactivity (much weaker than that of C-14) in 1957 was an important scientific achievement. In the following years, Lai and Rama together with a team of young dedicated workers toiled night and day to isolate and detect many other isotopes of widely different half-lives and chemical affinities, which are produced in the atmosphere but quickly sequestered in different chemical reservoirs of the earth system. The list includes Be-7, Be-10, P-33, Mg-28, Cl-38, S-38 and Si-32, the last one discovered in collaboration with Prof. E D Goldberg during Lai's first visit to Scripps Institution of Oceanography in 1958. In a classic paper, Lai and Peters worked out the production rates of these isotopes in the atmosphere to serve as a basis for their use as probes of atmospheric, hydrological and oceanic processes. A crucial finding was the usefulness of Si-32 for determining the residence time of water in deep seas. Around this time, Lai also organized at the Tata Institute of Fundamental Research the first Indian laboratories for radiocarbon dating and tritium measurements for application to archaeological and hydrological research. If cosmic ray interaction with a simple and diffuse gaseous mixture like the terrestrial atmosphere could spawn some dozen radioactive isotopes, its interaction with chemically more complex solid objects should produce a far greater variety of isotopes with a wide range of half-lives. This realization led Lai, Arnold and Honda to develop a new and extremely fruitful line of research on the detection and significance of radioactive isotopes produced by cosmic ray bombardment of atmosphere-free extra-terrestrial objects such as meteorites and the moon. With his early training in the use of nuclear emulsion plates to record cosmic ray interaction events, Lai was quick to realize the potential of the discovery of microscopic damage trails in rocks and minerals due to passage of high energy uranium fission fragments by R L Fleischer, P B Price and R M Walker. He and his colleagues saw in it an opportunity to unfold the records of ancient cosmic rays preserved in meteorites and lunar surface materials. Thrbugh imaginatively designed experiments to study cosmic ray-produced radioactivity, implanted atoms as well as tracks in key meteorites and lunar soils, they illuminated a large number of unexplored vistas. Notable examples are the temporal variation in the flux and energy spectrum of cosmic rays back to the beginning of planetary formation, evolutionary history of meteorites and lunar soil column and solar radiation history of silicate grains before their compaction into what are known as gas-rich meteorites. While still actively involved in the study of meteorites and lunar samples, Lai became deeply interested in the problems of modern oceanography following his joint faculty appointment in 1967 at the Scripps Institution of Oceanography. Thus began his collaboration with Professors H Craig, H E Suess, G Arrhenius and other leading lights in oceanographic research, and his nurturing of an active group of young scientists in this country to address themselves to significant problems in oceano¬ graphy. The GEOSECS programme set up to acquire coordinated physico-chemical data from the oceans also appeared at this juncture. Lai’s participation in this programme led to the investigation of the large scale circulation of oceans using Si-32 as a tracer, bottom water diffusion employing Fe(OH)3 impregnated acrilon fibres to concentrate key trace elements and isotopes, and the role of micron-size particulate matter in transporting elements from surface to deep waters. Lai succeeded Vikram Sarabhai as Director of the Physical Research Laboratory (PRL), Ahmedabad a constituent laboratory of the Indian Department of Space, in Introduction xi 1972.

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