ISSN:0149-0419    

DOI:10.1080/01490410050210481

出版商:Informa UK Ltd    

年代:2000

数据来源: Taylor

摘要:

We present an improved crossover adjustment procedure to determine mean sea surface height using TOPEX, 35-day repeat phase ERS-1, Geosat, and 168-day repeat phase ERS-1 satellite altimeter data. The mean sea surface frame defined by the TOPEX data is imposed as certain constraints in our crossover adjustment procedure rather than held fixed as in some other procedures. The new procedure is discussed in detail. Equations are developed to incorporate the a priori information of Topex data as well as other satellite altimeter data. The numerical computation result shows that the rms crossover discrepancies are reduced by an order of 1 cm when the Topex data is not fixed. Furthermore, the computed mean sea surface is less noisy and more realistic than that computed by the traditional procedure.

ISSN:0149-0419    

DOI:10.1080/01490410050210490

出版商:Informa UK Ltd    

年代:2000

数据来源: Taylor

摘要:

Historically, prediction of ocean floor depth, or bathymetry, has been based on the isostatic modeling and linearized relationships between gravity anomalies and bathymetry. The need for isostatic modeling limits the application of the resulting bathymetry predictions as constraints in geophysical models. An alternative technique making use of the Earth's vertical gravity gradient for predicting bathymetry is explored in this paper. This technique is based on the fact that the observed gravity gradient anomalies result primarily from local mass concentrations on the ocean floor, and that mass compensation by the oceanic crust has an insignificant effect on the gravity gradients, and can be neglected. The resulting bathymetry prediction therefore is independent of isostatic modeling assumptions, allowing it to be used as a constraint on models of lithospheric compensation and for other geodetic and geophysical applications.

ISSN:0149-0419    

DOI:10.1080/01490410050210508

出版商:Informa UK Ltd    

年代:2000

数据来源: Taylor

摘要:

Based upon the analysis of about 10,000 line km of echosounding and bathymetric data and variations in mass accumulation rate along the NW continental margin of India (between Kori creek and Mumbai), we have deduced that in the northern region (in the vicinity of the River Indus) the shelf-break occurs at a shallower depth and the slope is shallower, has the steepest gradient (<1:20), is smoother with no major features, and has reduced width (slope edge at 1450 m; width 19 km than off Mumbai). The width and depth of the slope edge gradually increases southwards, and is at maximum off DamanMumbai (slope edge depth 2900 m; width 84 km). The intensity of the occurrence of physiographic features also increases southwards. The shelf edge off Saurashtra is undulating and on the slope, regional notches and benches (the most prominent at 560 m) are observed. Further southwards off Khambhat-Mumbai, the slope is characterized by the presence of bathymetric highs and lows. We have also observed numerous features on the shelf, with a variable depth of the shelf-break. The gradient of the continental slope is also reduced from the northern region to the southern region. The variations in the gradient of the slope and the presence of distinct physiographic features in this area are examined vis-a-vis fluvial supply of the sediments into the region.

ISSN:0149-0419    

DOI:10.1080/01490410050210517

出版商:Informa UK Ltd    

年代:2000

数据来源: Taylor

ISSN:0149-0419    

DOI:10.1080/01490410050210526

出版商:Informa UK Ltd    

年代:2000

数据来源: Taylor

ISSN:0149-0419    

DOI:10.1080/01490410050210535

出版商:Informa UK Ltd    

年代:2000

数据来源: Taylor

ISSN:0149-0419    

DOI:10.1080/01490410050210544

出版商:Informa UK Ltd    

年代:2000

数据来源: Taylor