摘要:

An aeromagnetic survey of Kansas, conducted by the Kansas Geological Survey during the past 5 years, has been completed. The total intensity magnetic field contour map, along with spectrally filtered versions, reveals largescale magnetic patterns, which we correlate with basement composition and paleotectonics.A second vertical derivative map clearly demonstrates that the southern part of the Proterozoic Central North American Rift System (CNARS) does not terminate in central Kansas but continues along a southwestern trend to at least the Oklahoma border. Some of the current seismicity within the state appears to be correlated with reactivated faults within the CNARS.Apparent in northeastern Kansas is the presence of numerous highly magnetic shallow granitic plutons, known from drilling to be approximately 1350 m.y. old, embedded within the older, 1600—1700‐m.y.‐old mesozonal granitic crust.The total intensity magnetic field map reveals a series of magnetic lows trending approximately east‐west across the state. These may correspond to a paleoplate boundary between the older granitic terrane to the north and the younger, 1400‐m.y. rhyolitic and epizonal granitic terrane to

ISSN:0002-8606    

DOI:10.1029/EO062i017p00169

年代:1981

数据来源: WILEY

摘要:

The purpose of this note is to suggest a quantitative approach to deciding how much time to give a speaker at a scientific meeting. The elementary procedure is to use the preacher's rule of thumb that no souls are saved after the first 20 minutes. This is in qualitative agreement with the proverb that one cannot listen to a single voice for more than an hour without going to sleep. A refinement of this crude approach can be made by considering the situation from the point of view of a linear physical system with an input, a transfer function, and an output. We attempt here to derive an optimum speaking time through these considerations.

ISSN:0002-8606    

DOI:10.1029/EO062i017p00179

年代:1981

数据来源: WILEY

摘要:

Calculations that used Pioneer‐Venus measurements of atmosphere composition, temperature profiles, and radiative heating predicted Venus' surface temperature ‘very precisely,’ says the Ames Research Center. The calculations predict not only Venus' surface temperature but agree with temperatures measured at various altitudes above the surface by the four Pioneer Venus atmosphere probe craft.Using Pioneer‐Venus spacecraft data, a research team has virtually proved that the searing 482° C surface temperature of Venus is due to an atmospheric greenhouse effect. Until now the Venus greenhouse effect has been largely

ISSN:0002-8606    

DOI:10.1029/EO062i017p00182-01

年代:1981

数据来源: WILEY

摘要:

Two major changes characterize the evolution of the AGU annual meetings, in the eyes of Martin Walt, meetings chairman. Walt, the director of physical sciences at the Lockheed Palo Alto Research Laboratory, was recently appointed meetings chairman for AGU annual meetings through 1982 by AGU President J. Tuzo Wilson. Walt's term will end with the 1982 Fall Meeting in San Francisco; that meeting will be chaired jointly by Walt and his successor.The first change Walt sees is a more businesslike approach to the meetings than when he first attended more than a decade ago. ‘I think people are preparing their talks better now, the session chairmen are more rigorous in keeping to schedule, and the meeting facilities have been improved,’ Walt no

ISSN:0002-8606    

DOI:10.1029/EO062i017p00193

年代:1981

数据来源: WILEY

摘要:

The European Seismological commission met in its 17th General Assembly, in Budapest, August 21–29, 1980. Part of the meeting took place jointly with the European Geophysical Society. More than 150 seismologists from 25 countries attended and contributed to the sessions of subcommissions and the two joint symposia. The program gave a total of 152 scientific contributions. The symposia had as subjects: the Edsnet, the European Digital Seismic Network (convener: P.L. Willmore), and the earthquake hazard and prediction (convener: V. Karnik). The IASPEI was represented by President B.A. Bolt, who gave a frontier lecture on strong motion seismology, and Secretary R.D. Adams. H. Meyers, from Boulder, represented WDC‐A. Other seismologists from countries outside the European area attended and took part in the meeti

ISSN:0002-8606    

DOI:10.1029/EO062i017p00201

年代:1981

数据来源: WILEY