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继初期裂谷作用之后,在大陆边缘堆积的沉积物构成岩石圈上的一种负荷,由于其本身的重量而产生下陷。现在,对于较年青的以及年老的大陆边缘都采用一种所谓剥离(Back -stripping)研究方法,在这种研究中,将不同地质时期的沉积物和水的负荷从一大陆边缘移去。这些研究表明,许多因素均能影响大陆边缘的沉降和构造,其中包括:海面的升降、基底的抗挠强度、压实作用和古海洋深度等。但是,这些因素并不能解释所观测到的大陆边缘沉降与构造的全部特征,而且其中必定还涉及到其它的一些作用过程。继裂谷作用初期大陆边缘的引张之后最可能影响所观测到的沉降的因素是热收缩作用。简单的扩展模式虽然目前还存在许多问题,但是看是能够解释大陆边缘构造沉降的指数特征的。这些问题中最重要的是裂谷前和裂谷期的沉积物与裂谷后沉积物的相对比例以及横贯大陆边缘的地壳的变薄量。
Following the initial rifting, sediments deposited on the margins of the continent constitute a load on the lithosphere that sags due to its own weight. Now, for the younger and older continental margins, a so-called back-stripping approach is used in which sediment and water loads from different geologic times are removed from a continental margin. These studies show that many factors can influence the settlement and tectonic setting of the continental margin, including the rise and fall of the sea surface, the flexural strength of the basement, compaction and paleoceanographic depth. However, these factors do not explain all of the observed characteristics of continental margin settlement and tectonics, and certainly involve some other processes. The factor that most likely affects the observed subsidence following the extension of the initial continental margin following rifting is thermal contraction. Simple expansion mode Although there are still many problems, but it can be interpreted to explain the characteristics of the continental margin sedimentation index. The most important of these issues are the relative proportions of pre-Rift and Rift sediments to post-Rift sediments and the crustal thinning across the continental margin.