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2. PLATE TECTONICS REVOLUTION Geochem. Perspect. (IF 3.8) Pub Date : 2024-04-01 Richard H. Sillitoe
As undergraduates at UCL, we were conversant with Alfred Wegener’s theory of continental drift, but petrology, stratigraphy, sedimentology, palaeontology and structural geology were taught in the context of geosynclinal theory, as they were everywhere at the time, and I am sure that I was not alone in finding some of the concepts difficult to comprehend. As I was finishing up at UCL in 1968, the plate
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ACKNOWLEDGEMENTS Geochem. Perspect. (IF 3.8) Pub Date : 2024-04-01 Richard H. Sillitoe
My work over the years has depended enormously on the efforts of others in the exploration and mining industry, particularly the thousands of field geologists of many nationalities, races and creeds who have selflessly shared their field observations and geological, geochemical and geophysical knowledge and showed me around the deposits and prospects that they were exploring. Not to be forgotten, however
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5. BULK TONNAGE AND EPITHERMAL GOLD DEPOSITS Geochem. Perspect. (IF 3.8) Pub Date : 2024-04-01 Richard H. Sillitoe
In late 1978, during my first United Nations consultancy in Colombia, Rod Mowat, the project manager and committed gold bug, was convinced that the world gold price was going to increase dramatically because of high inflation fuelled by massive budget deficits. He recommended that I invest in gold stocks and learn about gold deposits because of the likelihood that gold exploration would become far
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6. METALLOGENIC PROVINCES Geochem. Perspect. (IF 3.8) Pub Date : 2024-04-01 Richard H. Sillitoe
The concept of metallogenic provinces and corresponding epochs has fascinated generations of economic geologists (e.g., Lindgren, 1909), but their definition is still somewhat qualitative. However, few would argue with regions, hundreds to thousands of kilometres long, with unusual concentrations of one or more specific metals that contribute an appreciable share of their global inventories being designated
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PREFACE Geochem. Perspect. (IF 3.8) Pub Date : 2024-04-01 Richard H. Sillitoe
It was with some surprise that I received an invitation from Sarah Gleeson, one of the editors of Geochemical Perspectives, to contribute my scientific life story. As I am neither a geochemist nor a research scientist, the initial reaction was to decline as gracefully as possible. My professional life has been devoted to the practice of mineral exploration, in particular for copper and gold deposits
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METALLOGENY AND MINERAL EXPLORATION – SOME PERSONAL REMINISCENCES Geochem. Perspect. (IF 3.8) Pub Date : 2024-04-01 Richard H. Sillitoe
The following personalised narrative aims to document the highlights of my involvement in some of the ground breaking developments in Economic Geology and their direct application to mineral exploration and discovery over the past half century. The story begins with my introduction to geology at secondary school and university, followed by doctoral research based on fieldwork in the Andes of South
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3. RADIOMETRIC DATING OF ORE DEPOSITS Geochem. Perspect. (IF 3.8) Pub Date : 2024-04-01 Richard H. Sillitoe
Upon arrival in Chile in 1965, the only available radiometric ages for rocks in the central Andes were from intrusions in northern and central Chile, with most of the determinations carried out using the lead-alpha zircon method, first by the US Geological Survey in Washington, DC and then by Francisco Munizaga at IIG’s in-house facility in Santiago (Ruiz et al., 1961, 1965). The ages, including one
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4. PORPHYRY COPPER MODEL Geochem. Perspect. (IF 3.8) Pub Date : 2024-04-01 Richard H. Sillitoe
During the early months of my IIG porphyry copper project in Chile, I had a revelatory moment on an evening LAN Chile flight from Arica south to Santiago (Fig. 1.8). From a window seat on the left side of the Sud Aviation Caravelle, I could see the line of Quaternary stratovolcanoes along the Chile-Bolivia border illuminated by the setting sun (Fig. 4.1). In the variably eroded centres of the stratocones
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7. SUCCESS AND CHALLENGES IN MINERAL EXPLORATION Geochem. Perspect. (IF 3.8) Pub Date : 2024-04-01 Richard H. Sillitoe
Long term involvement in mineral exploration engendered a keen interest in what strategies and methods are conducive to discovery of base and precious metal deposits, but I had never formally investigated the topic. That was about to change when, at the crack of dawn one day in February 1995, I received a phone call in London from the Metal Mining Agency of Japan (MMAJ) in Tokyo asking if I was interested
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8. EPILOGUE Geochem. Perspect. (IF 3.8) Pub Date : 2024-04-01 Richard H. Sillitoe
When Sarah Gleeson invited me to contribute this scientific life history three years ago, she said it would be hard work and time consuming, and she was absolutely right. It is undoubtedly the most difficult subject I have ever attempted to address and, embarrassingly, by far the most egotistical and personalised. It is to be hoped that older readers will identify with some of the scientific quandaries
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1. INTRODUCTION Geochem. Perspect. (IF 3.8) Pub Date : 2024-04-01 Richard H. Sillitoe
My father, an accountant and eventually Financial Director of a specialist industrial lubricants company, and my mother, a housewife although qualified as a Home Economics teacher, were keen hill walkers and mountaineers. When we were youngsters, they regularly took me and my brother on weekend trips from our various homes in and around Stoke-on-Trent, then a steel, coal mining and pottery manufacturing
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4. CARBON CAPTURE AND STORAGE (CCS) Geochem. Perspect. (IF 3.8) Pub Date : 2023-10-01 Eric H. Oelkers, Sigurdur R. Gislason
Over time it has become apparent that the increase in the CO2 concentration of the atmosphere, induced by anthropogenic activities, was and is continuing to provoke global warming, sea-level rise, ocean acidification and potentially global health issues (see Section 3). Concerns over these and other consequences of anthropogenic carbon emissions have led many to call for a global effort to attenuate
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5. THE FUTURE Geochem. Perspect. (IF 3.8) Pub Date : 2023-10-01 Eric H. Oelkers, Sigurdur R. Gislason
We wrote this Geochemical Perspectives in the fall of 2022. This was a curious time. During the summer of 2022 the world experienced some of the most unusual weather in years. Pakistan has experienced catastrophic floods. Much of Southern Europe experienced droughts more severe than seen in over a century. A heat-wave in the western United States during the fall of 2022 broke all-time temperature records
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CARBON CAPTURE AND STORAGE: FROM GLOBAL CYCLES TO GLOBAL SOLUTIONS Geochem. Perspect. (IF 3.8) Pub Date : 2023-10-01 Eric H. Oelkers, Sigurdur R. Gislason
Anthropogenic carbon emissions have overwhelmed the natural carbon cycle, leading to a dramatic increase in atmospheric CO2 concentration. The rate of this increase may be unprecedented in Earth’s history and is leading to a substantial increase in global temperatures, ocean acidification, sea level rise and potentially human health challenges. In this Geochemical Perspectives we review the natural
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1. INTRODUCTION Geochem. Perspect. (IF 3.8) Pub Date : 2023-10-01 Eric H. Oelkers, Sigurdur R. Gislason
We have in the past thought that our writing should always focus on our science. In part because we always have so much science to share and because this is what we have in common with our readers − the desire to solve some of the great questions and challenges of our world. Our opinions began to change somewhat at the 2013 Goldschmidt meeting in Florence. At a bar across from the Medici Chapel, over
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2. THE GLOBAL CARBON CYCLE AND CLIMATE Geochem. Perspect. (IF 3.8) Pub Date : 2023-10-01 Eric H. Oelkers, Sigurdur R. Gislason
The transfer of carbon among the various reservoirs of the Earth both influences the global climate and makes possible life itself. The relative size of the major carbon reservoirs is shown in Figure 2.1. The atmosphere is a relatively small carbon reservoir. In pre-industrial times it contained roughly 600 gigatons of carbon, C. This has increased to approximately 900 gigatons of carbon since that
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3. ANTHROPOGENIC INFLUENCES Geochem. Perspect. (IF 3.8) Pub Date : 2023-10-01 Eric H. Oelkers, Sigurdur R. Gislason
The natural carbon cycle described in the last section has been greatly influenced by human activity. Human intervention in the global carbon cycle is so large that it is often referred to as a new geologic epoch, “The Anthropocene” (Kolbert, 2011; Crutzen 2002). This epoch, however, has not yet been officially approved as a subdivision of geologic time.The beginning of Anthropocene is debated widely
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INDEX Geochem. Perspect. (IF 3.8) Pub Date : 2023-10-01 Eric H. Oelkers, Sigurdur R. Gislason
Abstract not available
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A JOURNEY IN NOBLE GAS COSMOCHEMISTRY AND GEOCHEMISTRY Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
I started my journey in science by studying noble gases implanted by the solar wind in dust grains on the surface of the Moon, and with many colleagues I have studied solar wind implanted noble gases in natural and artificial samples throughout my career, the latter exposed primarily by the Genesis space mission. Major questions are what noble gases in the solar wind can tell us about the present and
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6. CONCLUDING REMARKS Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
Looking at programmes of geo- and cosmochemistry meetings, I am always impressed by how much science can be illuminated by a single group of elements – the noble gases. I have covered a very small part of this in these pages, but especially at dedicated noble gas meetings like the DINGUE series, I am always amazed at what colleagues are working on that I had no idea about. This fascinating aspect is
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DEDICATION Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
For Catherinewith whom I share my life since my graduate student days and whose love, inspiration and support I could not be without.
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PREFACE Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
A few years ago, Janne Blichert-Toft asked me to review a manuscript by Bernard Marty that became a volume of Geochemical Perspectives, describing his career and the contributions of his group at the CRPG in Nancy to the geochemistry of the “atmophile” elements H, C, N, and the noble gases (Marty, 2020). I very much enjoyed this reviewing task. It allowed me to get even better insight into the career
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ACKNOWLEDGEMENTS Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
As is probably the case with almost every scientist, my path has been shaped by numerous colleagues, mentors and students. First I would like to highlight six persons who have been particularly important to me along the way.Peter Signer was by far the most important and influential person in my scientific life. His attitude as my supervisor during my graduate studies is aptly described with the German
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1. HOW – RATHER FORTUITOUSLY – I BECAME A NOBLE GAS COSMOCHEMIST Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
On January 3rd, 1976, I returned to Switzerland after a 15 month sojourn in South America, mostly spent in Guayaquil, Ecuador, but also by traveling around the continent, including an unforgettable trip to the Galapagos Islands. Two and a half years earlier, I had obtained my diploma in Physics (today we would call this a Master’s degree) at the Swiss Federal Institute of Technology in Zürich (known
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2. NOBLE GASES FROM THE SUN Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
The importance of noble gases in the Earth and Planetary sciences has been excellently explained in two previous volumes of the Geochemical Perspectives series by Manuel Moreira and Bernard Marty (Moreira, 2013; Marty, 2020). As Manuel explains, they are geochemical tracers par excellence because they are chemically (almost) inert and thus unaltered by chemical and biological reactions. They are also
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3. NOBLE GAS (AND OTHER) STUDIES ON METEORITES AND OTHER SAMPLES FROM FAR AWAY Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
Let me come back one more time to my early days in science. As described in the previous section, my scientific focus during my doctoral studies was almost exclusively on lunar samples and their noble gases. Only in passing did I realise that nature also provides us with other interesting matter from beyond our Earth. My knowledge about meteorites and their noble gases in particular tended towards
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4. NOBLE GASES IN TERRESTRIAL ROCKS Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
As noted in the introduction to Section 3, in the early- to mid-1980s I not only took my first steps away from solely studying lunar samples to becoming a meteoriticist, but also developed, more or less in parallel, an interest in noble gases (and radionuclides) in terrestrial samples. For a physicist with a meagre (to say the least) background in geology, this naturally required extensive collaboration
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5. NOBLE GASES IN WATER – THE COLLABORATION WITH EAWAG Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
Let me turn back the clock one last time, to the year 1986. Rolf Kipfer, better known to many as RoKi, with his fresh ETH Diploma in Geophysics, was about to start his doctoral thesis in Peter Signer’s group. We had some good ideas for Rolf, but no mature project yet. Coincidentally, around that time, Thomas (Tommy) Gold at Cornell University approached Peter with his theory of an abiogenic origin
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LIST OF ACRONYMS Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
Abstract not available
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4. NOBLE GASES IN TERRESTRIAL ROCKS Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
As noted in the introduction to Section 3, in the early- to mid-1980s I not only took my first steps away from solely studying lunar samples to becoming a meteoriticist, but also developed, more or less in parallel, an interest in noble gases (and radionuclides) in terrestrial samples. For a physicist with a meagre (to say the least) background in geology, this naturally required extensive collaboration
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3. NOBLE GAS (AND OTHER) STUDIES ON METEORITES AND OTHER SAMPLES FROM FAR AWAY Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
Let me come back one more time to my early days in science. As described in the previous section, my scientific focus during my doctoral studies was almost exclusively on lunar samples and their noble gases. Only in passing did I realise that nature also provides us with other interesting matter from beyond our Earth. My knowledge about meteorites and their noble gases in particular tended towards
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2. NOBLE GASES FROM THE SUN Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
The importance of noble gases in the Earth and Planetary sciences has been excellently explained in two previous volumes of the Geochemical Perspectives series by Manuel Moreira and Bernard Marty (Moreira, 2013; Marty, 2020). As Manuel explains, they are geochemical tracers par excellence because they are chemically (almost) inert and thus unaltered by chemical and biological reactions. They are also
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1. HOW – RATHER FORTUITOUSLY – I BECAME A NOBLE GAS COSMOCHEMIST Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
On January 3rd, 1976, I returned to Switzerland after a 15 month sojourn in South America, mostly spent in Guayaquil, Ecuador, but also by traveling around the continent, including an unforgettable trip to the Galapagos Islands. Two and a half years earlier, I had obtained my diploma in Physics (today we would call this a Master’s degree) at the Swiss Federal Institute of Technology in Zürich (known
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5. NOBLE GASES IN WATER – THE COLLABORATION WITH EAWAG Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
Let me turn back the clock one last time, to the year 1986. Rolf Kipfer, better known to many as RoKi, with his fresh ETH Diploma in Geophysics, was about to start his doctoral thesis in Peter Signer’s group. We had some good ideas for Rolf, but no mature project yet. Coincidentally, around that time, Thomas (Tommy) Gold at Cornell University approached Peter with his theory of an abiogenic origin
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LIST OF ACRONYMS Geochem. Perspect. (IF 3.8) Pub Date : 2023-04-01 Rainer Wieler
Abstract not available
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1. INTRODUCTION Geochem. Perspect. (IF 3.8) Pub Date : 2022-10-01 S. Wajih A. Naqvi
I was born on August 10, 1954, in Amroha, an ancient little town located some 130 km east of Delhi within the heart of the Indo-Gangetic Plain. The community my family is a part of is called Sadat-e-Amroha (Syeds of Amroha). Traditionally, this community has been quite conservative as it claims lineage to Prophet Muhammad through his daughter Fatima, a.k.a. Syeda (from which ‘Syed’, the first part
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5. SEASONAL ANOXIA OVER THE WESTERN CONTINENTAL SHELF OF INDIA Geochem. Perspect. (IF 3.8) Pub Date : 2022-10-01 S. Wajih A. Naqvi
In addition to the perennial ODZ in the open ocean, anoxic conditions also develop seasonally over the western Indian continental shelf. This phenomenon was first discovered in the 1950s by Karl Banse who came to India in 1958 to pursue research on tropical plankton. He was then a young man, having obtained a Ph.D. in Oceanography/Zoology from University of Kiel in 1955 followed by a post-doc at Institut
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9. THE TERRESTRIAL CONNECTION Geochem. Perspect. (IF 3.8) Pub Date : 2022-10-01 S. Wajih A. Naqvi
The National Academy of Sciences of the USA organised a Symposium on Nutrient Over-Enrichment in Coastal Waters in October 2000 in Washington, D.C. This was a fairly large meeting, which I also attended. Christine Todd Whitman, the then Governor of New Jersey, inaugurated the Symposium. I remember her because in her inaugural address she jokingly questioned why the area of the infamous dead zone in
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2. ANOXIA IN THE OPEN OCEAN AND ANOMALOUS LOCATION OF OXYGEN DEFICIENT ZONES IN THE INDIAN OCEAN Geochem. Perspect. (IF 3.8) Pub Date : 2022-10-01 S. Wajih A. Naqvi
One of the main goals of the Challenger Expedition was “to investigate the distribution of organic life at different depths and on the deep seafloor”. This was because, well into the 19th century, many people – prominent among whom was the British naturalist Edward Forbes (1815–1854) – had believed that the deep sea was anoxic and, consequently, azoic (Anderson and Rice, 2006). The Challenger expedition
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3. NITROGEN CYCLING IN OPEN OCEAN ODZS Geochem. Perspect. (IF 3.8) Pub Date : 2022-10-01 S. Wajih A. Naqvi
Heterotrophic organisms derive energy by oxidising organic matter produced by autotrophs. There are a number of chemical species dissolved in seawater that may serve as electron acceptors (oxidants) for this purpose. The most important of these are oxygen, nitrate (and other oxidised forms of nitrogen), manganese (IV), iron (III) and sulfate. The energy gained by the heterotrophs using these electron
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ACKNOWLEDGEMENTS Geochem. Perspect. (IF 3.8) Pub Date : 2022-10-01 S. Wajih A. Naqvi
I wish to express my sincere gratitude to all my colleagues and co-workers, too many to name individually, who have contributed to the generation of information summarised here. I am grateful to the Directors of NIO and the Director-Generals of CSIR who I worked under, as well as the funding agencies (especially the Ministry of Earth Sciences) for their support and encouragement throughout my career
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ANOXIA-RELATED BIOGEOCHEMISTRY OF NORTH INDIAN OCEAN Geochem. Perspect. (IF 3.8) Pub Date : 2022-10-01 S. Wajih A. Naqvi
This article provides a brief account of my early life and career, and a more detailed description of the contributions of the groups with which I have been associated to the biogeochemistry of the North Indian Ocean, especially nitrogen cycling in oxygen deficient waters.Some of the most intense oxygen depletion in the water column in the open ocean occurs at mid-depths in the two northern basins
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4. REDOX SENSITIVE ELEMENTS OTHER THAN NITROGEN Geochem. Perspect. (IF 3.8) Pub Date : 2022-10-01 S. Wajih A. Naqvi
As stated earlier, in addition to nitrogen, several other polyvalent elements also undergo redox transformations in anoxic waters (Table 1). Studies in the Arabian Sea undertaken prior to JGOFS had focussed on manganese (Mn), iron (Fe) and cerium (Ce) (Saager et al., 1989; German and Elderfield, 1990). These authors observed concentration maxima in dissolved Mn, Fe and Ce (operationally defined as
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6. GLOBAL EFFORT TO ASSESS OCEAN DEOXYGENATION: TRENDS IN THE INDIAN OCEAN Geochem. Perspect. (IF 3.8) Pub Date : 2022-10-01 S. Wajih A. Naqvi
Human activities are affecting oxygen distribution in the ocean in two major ways (Keeling et al., 2010; Breitburg et al., 2018; Naqvi, 2020). (1) Rising levels of greenhouse gases in the atmosphere are also causing ocean warming, with as much as 93 % of the extra energy being retained by the planet going into the oceans. Warming may affect the oxygen balance of subsurface waters through a decrease
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7. SOME OUTSTANDING ISSUES CONCERNING INDIAN OCEAN’S OXYGEN DEFICIENT ZONES Geochem. Perspect. (IF 3.8) Pub Date : 2022-10-01 S. Wajih A. Naqvi
Despite huge advances over the past few decades in our understanding of the biogeochemistry of ODZs, there are still a couple of fundamental, inter-related questions that remain to be satisfactorily answered, with one of them more specific to the North Indian Ocean. (1) Can substantial combined nitrogen loss through heterotrophic denitrification and anammox occur in the presence of oxygen in traces
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8. OCEANOGRAPHY OF MARGINAL SEAS OF THE NORTHWEST INDIAN OCEAN Geochem. Perspect. (IF 3.8) Pub Date : 2022-10-01 S. Wajih A. Naqvi
The Northwestern Indian Ocean contains two marginal seas: the Red Sea and the Persian Gulf. Located in a highly arid region, these seas experience negative water balance (large excess of evaporation over precipitation and river runoff) resulting in very high salinities and Mediterranean-type (anti-estuarine) circulation i.e. net flow of fresher seawater into these basins close to the surface and outflow
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1. THE PROBLEM Geochem. Perspect. (IF 3.8) Pub Date : 2022-04-01 Lourens G.M. Baas Becking, Alexander J.P. Raat
Man lives on the earth, and although his Kingdom is not of this world, this seems insufficient reason to neglect our relation with our foster planet, which has been, and probably will remain, the sole abode of mankind. As Henderson (1913) pointed out in his masterly essay The Fitness of the Environment,1 current opinion, up to the birth of natural sciences was that the earth was created as our playground
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APPENDIX Geochem. Perspect. (IF 3.8) Pub Date : 2022-04-01 Lourens G.M. Baas Becking, Alexander J.P. Raat
Left page: [Quotations from the Bible (see transcription of the manuscript) and 2 D version of a 3 D tetrahedron or triangular pyramid, to depict the oxidation and reduction of carbon and nitrogen compounds.]Joshua speaks to the tribes of Joseph (Joshua 17:18) but the mountain shall be thine; for it is a wood and thou shalt cut it down: and the outgoings of it shall be thine.1Genesis 1:28 Be fruitful
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FOREWORD Geochem. Perspect. (IF 3.8) Pub Date : 2022-04-01 Lourens G.M. Baas Becking, Alexander J.P. Raat
Lourens Baas Becking is a pivotal figure in the history of microbial ecology and geobiology, having coined the term “Geobiologie” in the title of his 1934 opus (Geobiologie ofinleiding tot de milieukunde). This work has been translated into English (Baas Becking, 2016), so everyone now can read of Baas Becking’s contributions and see for themselves the context of his most famous proposition “Everything
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PREFACE Geochem. Perspect. (IF 3.8) Pub Date : 2022-04-01 Lourens G.M. Baas Becking, Alexander J.P. Raat
I wrote a book about the earth and man. He was always there as a hunting dog on the trail, restless, enthusiastic, with impromptu promptings, which helped me. For example, I wrote about a city with its energy production as an organism. He gave me to read Ezekiel 27, which describes the riches of Tyrus, and when I spoke of the devastation that man wreaks on earth, he showed me places from Isaiah, and
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GEOBIOLOGY Geochem. Perspect. (IF 3.8) Pub Date : 2022-04-01 Lourens G.M. Baas Becking, Alexander J.P. Raat
Lourens Baas Becking (1895-1963) was a Dutch plant physiologist, trained in the Botanical Laboratory of Utrecht University. After graduating in 1919, he worked in America at Stanford University, where he obtained his Doctor’s degree in 1921. From 1928, he was Herzstein Professor of Biology and Director of the Jacques Loeb Physiological Laboratory at the Hopkins Marine Station in Palo Alto. In 1931
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2. THE EARTH Geochem. Perspect. (IF 3.8) Pub Date : 2022-04-01 Lourens G.M. Baas Becking, Alexander J.P. Raat
Astronomists and geologists agree that this universe suffered a great conflagration about 2,000,000,000,0000 years (two thousand million years) ago. Umbgrove (1942) has dealt with these and called allied matter in his book The Pulse of Earth.1 Our planetary system seems to have originated in this epoch and, according to all probability, the earth, together with the other planets, was torn from the
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3. THE MILIEU Geochem. Perspect. (IF 3.8) Pub Date : 2022-04-01 Lourens G.M. Baas Becking, Alexander J.P. Raat
The limits of the milieu for a certain organism strictly pertain to a certain stage in its development. The milieu for a larva and for an imago may be different. Still, we might consider an integration of the boundaries for a certain stage, as long as that stage requires a constant milieu. Geobiologically this is an organism distinct from another developmental stage. Potential milieu is limited by
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4. THE ORGANISMS Geochem. Perspect. (IF 3.8) Pub Date : 2022-04-01 Lourens G.M. Baas Becking, Alexander J.P. Raat
If we consider the milieu as the stage of the life drama (Lotka), the living beings are the actors and the drama consists, like any proper ‘roman familial’, “of the relation between these actors with their environment and with another.”1 If we want to consider living things from this point of view, we are much more concerned with their activities and with their composition as with their form. Our problem
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5. INFLUENCE OF THE MILIEU UPON THE ORGANISMS Geochem. Perspect. (IF 3.8) Pub Date : 2022-04-01 Lourens G.M. Baas Becking, Alexander J.P. Raat
The living mass of one organism, or a population seems to increase according to a special law. The increase is often first fast, then slows down, until growth stops. There seems to be for the organism and for the population a limit which is slowly reached. Robertson compared the process to an autocatalytic reaction in which the reaction velocity dy/dt = y (a-y) in which y is the amount of substance
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6. INFLUENCE OF ORGANISMS Geochem. Perspect. (IF 3.8) Pub Date : 2022-04-01 Lourens G.M. Baas Becking, Alexander J.P. Raat
From Lavoisier (1790) we owe the rule of the indestructability of matter: “rien ne se perd, rien ne se crée”. Robert Mayer (1842) has created its analogue in energetics: the rule of the indestructibility of energy, “das Gesetz der Erhältung der Kraft”. Both rules have become to one since Einstein’s demonstration of the identity of matter and energy.Now Clausius formulated the second law of thermodynamics