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1. |
Uranium in the Earth's core |
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Eos, Transactions American Geophysical Union,
Volume 65,
Issue 44,
1984,
Page 785-785
Roy C. Feber,
Terry C. Wallace,
Leona Marshall Libby,
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摘要:
That there is no radioactivity in the earth's core is a concept that has long been held. The reason is that the major radioactive elements, potassium and uranium, exist as siderophobic compounds, such as silicates and oxides, in the earth's mantle and thus were thought to be immiscible with the metal core. An experimental measurement of the binary system of steel and UO2, however, shows that above 3120 K the system is a two‐phase liquid, the one rich in UO2and the other poor in UO2. The phase diagram predicts that there must be a temperature above which there is total miscibility between UO2and steel. This temperature may be above the boiling point of UO2, estimated as 3750 K. The temperature at the core‐mantle interface of the earth's interior is estimated most recently as 3130 K. Thus there is a strong likelihood that uranium exists in the earth's metal core. Hence the natural alpha radioactivity of uranium offers a power source for the earth's magnetic dyn
ISSN:0002-8606
DOI:10.1029/EO065i044p00785-01
年代:1984
数据来源: WILEY
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2. |
Land and seabed deformation |
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Eos, Transactions American Geophysical Union,
Volume 65,
Issue 44,
1984,
Page 786-786
David W. Robb,
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摘要:
The development of techniques to monitor undersea and ground surface deformation and sea level changes will be highlighted at a session of invited geodesy papers at the AGU Fall Meeting, to be held in San Francisco, Calif., December 3–7 , 1984.The oceans conceal the earth's largest sudden deformation events. Subduction earthquakes at great plate boundaries produce 10–20‐m motions of the crust near offshore trenches. Inflation of undersea volcanoes and the spreading of midocean rifts also produce large changes that may go unnoticed. The great tsunami‐generating earthquakes may be associated with unusually large vertical movements of the seabed; these earthquakes also may cause vast undersea landslides. Technologies to predict these large movements have potential for improving earthquake prediction, tsunami warning, and prediction of volcanic eruptions. Fred Speiss, chief editor of a recent National Academy of Sciences book on undersea deformation, will chair this
ISSN:0002-8606
DOI:10.1029/EO065i044p00786-01
年代:1984
数据来源: WILEY
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3. |
Geomagnetism of Baked Clays and Recent Sediments |
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Eos, Transactions American Geophysical Union,
Volume 65,
Issue 44,
1984,
Page 787-787
Edward A. Mankinen,
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PDF (205KB)
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摘要:
This book is an outgrowth of the symposium entitled “Time Scales of Geomagnetic Secular Variations,” which was held at the 4th Assembly of the International Association of Geomagnetism and Aeronomy (Edinburgh, U.K., August 1981). The volume includes many of the papers presented, which described paleomagnetic results from both archeologic materials and Holocene geologic deposits, as well as contributions solicited from other researchers in the fields of archeomagnetism and paleomagnetism. In a remarkably short time after the conclusion of the symposium the editors were able to elicit, edit, and assemble a large body of material from 40 individuals into a thoughtful, wellorganized prod
ISSN:0002-8606
DOI:10.1029/EO065i044p00787
年代:1984
数据来源: WILEY
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