Word: geochemist
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...Soviets have some convincing evidence for their claim. Using special high-temperature ovens, they incinerated peat collected from the region. In the ashes they found many strange, irregularly shaped and extremely hard black grains, which laboratory examination revealed to be tiny diamonds. Institute Geochemist Emil Sobotovich explained that the little diamonds could only have been created under extraordinarily high pressures. Such conditions deep within the earth produce diamonds, which are brought to the surface in eruptions of molten magma through kimberlite, or volcanic, pipes. But extreme pressures also occur during high-velocity collisions between celestial objects; uralites, a class...
...added evidence that the diamonds arrived in a meteorite, Sobotovich cited their level of carbon 14, a radioactive isotope of carbon found in meteorites that have been subjected to prolonged bombardment by cosmic rays in space. University of Chicago Geochemist Edward Anders cautions that even a trace of unburnt peat could produce a high reading of carbon 14. But, based on these levels, the Soviets calculate that the meteorite must have weighed at least 4,000 tons...
...when -did life begin? Cyril Ponnamperuma, 55, a Ceylon-born geochemist at the University of Maryland, has been seeking answers to this question for much of his career. He has created precursors of life in laboratory simulations of the earth's primitive atmosphere and while with NASA in 1970, identified amino acids (the building blocks of protein) in the Murchison meteorite, which had fallen in Australia a year earlier. Last week, at a meeting of the American Chemical Society in Washington, Ponnamperuma presented three new pieces of evidence that the processes leading to the formation of life can take...
...ship in midocean, about 200 miles southwest of the Azores, had penetrated 1,910 ft. into the earth's hard crust under the Atlantic bottom sediment. It returned core samples from depths never before explored; the previous record penetration was 260 ft. into the submarine crustal rock. Said Geochemist William Melson of the Smithsonian Institution: "It was like probing into the unknown, getting samples we had thought about for years but had never been able to reach...
...volcanic vents on earth, they speculated that volcanic activity might well have occurred on the moon as recently as 200,000 or 300,000 years ago. That would have upset the widely held view that the moon has been largely dormant for more than 3 billion years. Said NASA Geochemist Robin Brett: "If the material is indeed so young, we may have witnessed one of the important finds in Apollo geology...