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991.
D. Q. Bowen 《Geological Journal》1973,8(2):207-224
The Pleistocene rock-stratigraphic record is accorded more or less traditional time-stratigraphic interpretation which was held widely before application of an Irish developmental model in 1960. The following sequence of events are recognised: (1) Complete glaciation, of indeterminate age, which antedated the raised beach interglacial. (2) The raised beach episode which is shown to be the last (Ipswichian) interglacial. (3) The last (Devensian/Weichselian) glaciation, followed by possible readvance in northwest and northeast Wales; prior and subsequent to glaciation periglacial conditions obtained. It is shown that the Irish model, relying heavily as it does on the equation of rock and time stratigraphy, is inapplicable in Wales. 相似文献
992.
M. D. Max 《Geological Journal》1973,8(2):375-386
Lewisian gneisses, Moinian and Dalradian sediments, and dolerites have been deformed and metamorphosed under Amphibolite Fades conditions. The metamorphic climax, with the growth of kyanite and staurolite, occurred after the cessation of the second deformational episode and before the onset of the third. Plagioclase growth ceased at or about the time of kyanite and staurolite nucleation. Metamorphic effects become less to the south and southeast while the most advanced stages occur around Inver. A single heat pulse appears to be not directly related to any structure. 相似文献
993.
994.
Nikos D Lagaros 《地震工程与工程振动(英文版)》2008,7(1):45-56
995.
INTRODUCTIONWeatherforecastingasamajorsubjectinatmosphericsciencehasdevelopedsincethe 1 950’sintoamodernscience .Numericalweatherforecastmodelsareextensivelyandfrequentlyusedtocheckthetheories,ruleouttheoldincorrectonesandpresentnewideas,andsuggestmethods… 相似文献
996.
James D Irish 《Marine Geology》1976,21(3):M31-M35
A bathymetric and magnetic survey of the California Seamount region (17°40′N × 124°00′W) shows that existing charts are in error. California Seamount is a peak extending to within 454 m (248 fathoms) of the surface. Its true location is 17°41′N × 124°01′W, 25 km southwest of the charted position. Near the old charted position there is an elongated feature which extends to within 1818 m (994 fathoms) of the surface. Both features are located on the Clarion Fracture Zone. 相似文献
997.
998.
999.
A nearly continuous zone of sediment waves is present on the lower continental rise off western Morocco which parallels the regional bathymetric trends. The individual sediment waves within the zone migrate upslope with time and, in general, also trend parallel to the regional bathymetric contours. These observations suggest that geostrophic contour currents are responsible for the formation of sediment waves. Physical oceanographic measurements and sea-floor photographs indicate only a very weak bottom circulation in this region. This suggests either that strong bottom currents are not essential for the formation of sediment waves or that relatively stronger bottom currents flowed along the continental margin of Morocco in the recent past. Turbidity flows may also influence the distribution of these sediment waves. 相似文献
1000.