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对西北太平洋日本海沟和南海海槽的地震剖面和 DSDP 钻探结果以及拖网采样资料的重新解释表明,所谓“大洋地壳”系由包含部份元古代正石英岩的前寒武纪大陆地壳组成。这一认识得到了古地理证据的支持。古地理证据表明在古生代—中生代—老第三纪时期在日本列岛的现今太平洋一侧有大型陆块存在,它们是向特提斯海的日本部份输送大量沉积物的物源区。现今西北太平洋的大部份地区在古生代至早中生代时期曾是出露于海面的,或部份为很浅的浅海,大约在侏罗纪末开始成为深海。上述结论要求对西北太平洋地区岛弧和海沟的地质发育的板块构造模式作根本修正。
The reinterpretation of seismic profiles and DSDP drilling results and trawl sampling data from the Japan Trench and South China Sea troughs in the western North Pacific shows that the so-called “oceanic crust” is composed of the Precambrian continental crust containing a portion of Proterozoic normal quartzite. This understanding is supported by paleogeographic evidence. Paleogeographic evidence indicates that large-scale land masses exist on the present Pacific side of the Japanese archipelago during the Paleozoic-Mesozoic-Oligocene periods and are source areas for massive deposition of sediment into the Japanese part of the Tethys Sea. Most parts of the Northwest Pacific today were exposed to the sea from the Paleozoic to the Early Mesozoic, or partly shallow, shallow waters, beginning to become deep-sea at the end of the Jurassic. The above conclusion calls for a fundamental correction of the plate tectonic pattern of the geological development of island arcs and trenches in the western North Pacific.