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最近,多道地震反射剖面揭示了美国东部近海大陆斜坡下有早白垩—侏罗纪碳酸盐岩地台边缘存在的可能性。在无反射界面的地块上,地震反射具有高振幅双曲线状的特征。地震折射研究测得了高振幅反射界面下的地层速度。脊地台(Back-Plat form)的层状沉积形成高振幅的连续混响反射层,它们朝海洋伸入地台边缘的无反射界面的地块中。脊地台沉积的朝陆斜坡,是由于较为正向的承压地台构造的差异下降和倒转而产生的。覆盖的外滨海沉积形成超覆反射层,并从地台边缘逐渐向附近的盆地倾斜。这种地台边缘构造形成了地下起伏几公里的马头丘,进而作为年轻大陆斜坡的基底.很明显,这种马头丘完全控制了后来形成的大陆架边缘的位置。在某些情况下,碳酸盐岩地台边缘沿海向逐渐向下延伸,从大陆过渡到洋壳。因此,现在的大陆架边缘,正如新泽西——特拉华近海的情况那样,是位于洋壳之上的。疏浚工程和深海钻探工程研究,对美国近海几个地区的碳酸盐岩地台边缘进行了采样,并且,这些已经明确的地震特征已被用来解释迄今还未取得样品的、沿走向延伸几千公里的地下构造。
Recently, the multi-channel seismic reflection profile revealed the possibility of the presence of the margin of the Early Cretaceous-Jurassic carbonate platform beneath the continental slope of the eastern United States. Seismic reflection has the characteristics of hyperbolic hyperbolic on the massif without reflection interface. Seismic refraction studies have measured formation velocities at high-amplitude reflection interfaces. Layered deposition of the Back-Plat form creates a high-amplitude continuous reverberation reflector that extends into the ocean into the mass of the landfill with no reflection interface. Landward slope of the ridge platform deposition is due to a more positive pressure bearing platform structure difference between the decline and inversion generated. The covered outer coastal sediments form overlying reflective layers and are gradually inclined from the edge of the platform to nearby basins. The marginal structure of this platform formed a horse-head mound a few kilometers below the ground, which served as a base for a young continental slope, apparently completely controlling the position of the resulting continental shelf edge. In some cases, the margins of the carbonate platform gradually extend down the coast and transition from the mainland to the oceanic crust. As a result, the margins of the present continental shelf are above the oceanic crust, as is the case with the New Jersey-Delaware Offshore. Dredging and deep-sea drilling engineering studies sampled the carbonate platform margins in several parts of the US offshore and these well-defined seismic features have been used to explain the hitherto unexpressed samples that extend thousands of miles along the strike Underground structure of kilometers.