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941.
The Solomon Sea Plate was widely developed during late Oligocene, separating the proto-West Melanesian Arc from the proto-Trobriand Arc. Spreading in the Bismarck Sea and in the Woodlark Basin resulted from interaction between the Pacific and Australian Plates, specifically from the collision of the proto-West Melanesian Arc with north New Guinea, which occurred after arc reversal. This model explains the extensive Miocene, Pliocene, and Quaternary volcanism of the Papua New Guinea mainland as it related to southward subduction of the Trobriand Trough. Our interpreted plate motions are concordant with the geological evidence onshore and also with complex tectonic features in the Solomon Sea Basin Region. 相似文献
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An approximate method is presented to estimate the hydrodynamic loading and structural response of an idealized offshore platform subjected to a regular train of linear surface waves. The platform is taken to consist of four bottom-mounted, flexible, circular cylinders supporting a rigid deck and is assumed to be aligned parallel to the incident wave direction. The response of each column is assumed to be one-dimensional and to be governed by linear beam theory. The solution technique for the fluid velocity potential involves replacing scattered waves by equivalent plane waves together with non-planar, first-correction terms, and can be shown to be a large spacing approximation.Numerical results are presented which show the effect of hydrodynamic interference and structural flexibility on the platform response. 相似文献
944.
OBS’s were deployed for 26 to 29 days in the eastern Bismarck Sea to investigate the back-arc spreading. Hypocenters of 186 shallow earthquakes were determined using P- and S-waves from at least five stations. In the western survey area, a transform fault zone is marked by a linear micro-earthquake activity striking N65°W and less than 5 km wide. The predominant type of their focal mechanisms is strike-slip. In the eastern area, several intermittent zones of micro-earthquakes and their strike-slip type focal mechanisms suggest the location of short-length transform faults separating en-echelon spreading ridges. 相似文献
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949.
Abandonment and recovery solution of submarine pipelines 总被引:1,自引:0,他引:1
T.K. Datta 《Applied Ocean Research》1982,4(4):247-252
950.
K. T. Pickering 《Geo-Marine Letters》1982,2(1-2):41-46
Deep-water siliciclastic systems are classified primarily on their shape as: submarine fans with well developed or poorly
developed morphology, slope drapes, for example, over relatively stable basin margins, fault-scarp aprons, canyons and large
channels, under-supplied sheet systems such as abyssal plains, non-fan ponded systems such as over-supplied perched basins,
and fan deltas. Collectively, or separately, these systems may form sedimentary basin fills that can be over or under-supplied
with respect to the sediment input although most systems will tend toward over-supply/overflow with time. Finally, the sum
total of the siliciclastic systems and basins can be used to define the tectonic milieux such as passive, strike-slip and
convergent margins. 相似文献