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1. |
Material transfer in an arc‐ridge collision zone |
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Eos, Transactions American Geophysical Union,
Volume 72,
Issue 40,
1991,
Page 425-431
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摘要:
The influence of colliding and subducting ridges on the structural evolution of volcanic island arcs was investigated during Leg 134 of the Ocean Drilling Program (ODP) in the Central New Hebrides Island Arc, Southwest Pacific. Documenting tectonic accretion of colliding ridges onto the forearc of the central New Hebrides Island Arc (Vanuatu) and fragmentation of the island‐arc crust were the primary drilling objectives. Other objectives included studies of compressional dewatering, diagenetic alteration of pore fluids with rocks of an accretionary mass, and the tectonic evolution of a colliding guyot. Ridge‐arc collisions significantly alter the morphology and structure of volcanic island arcs and continental margins; however, the processes of tectonic deformation are poorly understood. Leg 134 documented for the first time material transfer from a ridge to an arc and defined the style of deformation occurring in the forearc area of a ridge‐arc collision
ISSN:0002-8606
DOI:10.1029/90EO00314
年代:1991
数据来源: WILEY
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2. |
Magellan “Venusquake” evidence reconsidered |
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Eos, Transactions American Geophysical Union,
Volume 72,
Issue 40,
1991,
Page 426-427
Stephen Cole,
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摘要:
What initially appeared to be a remarkable discovery by NASA's Magellan radar mapping mission—direct visual evidence of active tectonics on Venus—may actually have been distortion in the data and not an actual change on the planet's surface, according to mission scientists. At a press conference at the Jet Propulsion Laboratory on August 30, project scientist Steve Saunders presented two radar images of the same region in Aphrodite Terra, taken eight months apart, that showed a change in the topography. A fracture in the earlier image appeared covered with a broad bright patch in the second image. The patch was interpreted as being a landslide caused by a “Venusquake” that had occurred sometime between the two flyovers of the area by the Magellan spa
ISSN:0002-8606
DOI:10.1029/EO072i040p00426
年代:1991
数据来源: WILEY
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3. |
Early data on Earth's wobble reexamined |
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Eos, Transactions American Geophysical Union,
Volume 72,
Issue 40,
1991,
Page 427-427
Charles Blue,
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摘要:
Modern data show that the Earth is wobbling much differently than earlier data indicated, according to a paper published in the September issue ofGeophysical Research Letters. The paper examines flaws that exist in two data sets commonly used to determine the amount of the Earth's wobble.N. E. King and D. C. Agnew of the University of California at San Diego compared recent measurements of polar motion (wobble) made by space survey methods with older optical measurements. The new data reveal that the retrograde (clockwise) annual wobble of the Earth is much less than in the older data. The researchers state that this implies systematic errors in the older data.
ISSN:0002-8606
DOI:10.1029/EO072i040p00427-01
年代:1991
数据来源: WILEY
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4. |
Recent Ph.D.s |
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Eos, Transactions American Geophysical Union,
Volume 72,
Issue 40,
1991,
Page 428-428
Anonymous,
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ISSN:0002-8606
DOI:10.1029/EO072i040p00428
年代:1991
数据来源: WILEY
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5. |
“Earth and Sky” Radio Program debuts |
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Eos, Transactions American Geophysical Union,
Volume 72,
Issue 40,
1991,
Page 429-429
M. Catherine DeVito,
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摘要:
“Earth and Sky,” the radio show produced in association with AGU by Deborah Byrd and Joel Block, aired for the first time on September 30. The 2‐minute shows will discuss a topic in Earth and space science and inform listeners of what to look for in the night sky. Many shows will be dedicated to answering listeners' questions about Earth and the universe. The first few topics presented on “Earth and Sky” include the ocean bottom, the nature of water, meteor showers, how Earth came to be, planets orbiting other suns, earthquakes, and Earth's
ISSN:0002-8606
DOI:10.1029/EO072i040p00429-01
年代:1991
数据来源: WILEY
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6. |
Acting Manager of ONR Ocean Optics |
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Eos, Transactions American Geophysical Union,
Volume 72,
Issue 40,
1991,
Page 430-430
Anonymous,
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摘要:
On September 9, Gary Gilbert assumed the duties of acting manager of the oceanic optics program at the Office of Naval Research (ONR). Gilbert has replaced Curt Mobley, who resigned on September 4. Gilbert was last at the Naval Oceans Systems Center in San Diego, where he performed naval research in areas related to oceanic optics. He will serve as acting program manager until a permanent replacement is identified for the position, which will be advertised in the near future.
ISSN:0002-8606
DOI:10.1029/EO072i040p00430
年代:1991
数据来源: WILEY
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7. |
Flux transfer events and reconnection at the magnetopause |
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Eos, Transactions American Geophysical Union,
Volume 72,
Issue 40,
1991,
Page 431-434
W. D. Gonzalez,
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摘要:
For the general reader on magnetopause reconnection, it would appear that mixed information is coming from the global and quasi‐steady type of large‐scale reconnection (LSR) models and from the “patchy” and transient character of models related to flux transfer events (FTEs). I will attempt here to address complementary aspects of both types of models, with the goal of moving toward a unified model of magnetopause reconnection.Motivated by the Eos article on transient reconnection at the magnetopause byLockwood et al.[1990] as well as by a previous article on the subject byLee[1988], both of which serve to summarize a large body of work since the initial papers on FTEs or “flux erosion events” byRussell and Elphic[1979] andHaerendel et al.[1978], I would like to comment on two aspects involving FTEs and LSR [Petschek, 1964;Gonzalez and Mozer, 1974;Vasyliunas, 1975;Forbes and Priest, 1987;Sonnerup,
ISSN:0002-8606
DOI:10.1029/90EO10315
年代:1991
数据来源: WILEY
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