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沿国际海洋钻探计划协作阶段(IPOD)各剖面对会聚边缘进行的研究,证实了弧后盆地内洋底扩张以及会聚边缘前沿有构造加积沉积体的看法,但监非所有会聚边缘都有巨大的加积复杂体,而且在解释这些会聚边缘时还需要有其它不经常使用的概念。如果承认目前板块会聚的速率的话,那么,进入所研究的海沟中的大部分沉积物很可能被俯冲了而不是被加积了。在某些实例中,大陆基底被构造削蚀作用截断而发生位移。有些会聚边缘,在俯冲过程中曾有较大的沉降,贝尼奥夫带以上的地壳看来已由壳下侵蚀而变薄,或者和田—贝尼奥夫带的形状(Wadati—Benioff)已经改变。不管怎样,由于仅一部分沉降可以用侵蚀作用来解释,因而俯冲速率变化引起的热结构改变可能就成了主要的原因。为了区分与俯冲有关的各种过程,通常需要有从钻探样品获得的时间地层资料来复原大陆边缘的动力学历史。
A study of converging margins along various sections of the IPOD collaboration phase has confirmed the view that the ocean floor is expanding within the backarc basin and there is tectonic accretion sediments on the frontward of convergent margins but not all convergent margins The addition of complex complex body, but also in the interpretation of these convergence edge also need to have other infrequently used concept. If you acknowledge the current rate of plate convergence, most of the sediment that enters the trench under study is likely to be subdued rather than being accreted. In some instances, the continental base is truncated by structural erosion and displaced. Some of the converging margins have had larger subsidence during subduction, the crust above the Benioff belt appears to have been thinned by erosion under the shell, or the shape of the Wadati-Benioff belt (Wadati-Benioff) change. However, since only a portion of the subsidence can be explained by erosion, thermal structural changes due to changes in subduction rates may be the main cause. In order to distinguish between processes related to subduction, it is usually necessary to recover the dynamic history of the continental margin from the time-stratigraphic data obtained from drilling samples.