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在西南日本秋吉地区通过运用地层学、时代、和岩石学特征来再造该区的增生大洋岩体层序—石灰岩、燧石、绿岩的沉积环境。根据地层和放射虫古生物研究成果确定出四套同时期的大洋岩体,其时代范围从早石炭纪晚期到中二叠纪晚期。沉积物位于海底山顶部、上翼部、下翼部和基脚部,其周围洋底上的沉积物分别为礁灰岩,含针状燧石的碎屑灰岩、含针状燧石的位移石灰岩、放射虫燧石;各套岩石都位于绿岩之上。放射虫燧石为比针状燧石更远端相。这些岩体沉积于没有陆源物质进入的开阔海中形成的玄武质海山之上及其周围的沉积物。
The sedimentary environment of limestone, chert, and greenstone in the area of the accretionary oceanic rocks in the area is reconstructed by using stratigraphy, geochronology and petrology features in the autumn Kyrgyz region of Southwest Japan. Four sets of contemporaneous oceanites were identified based on the stratigraphic and radio-parasite paleontological studies, dating from the late Early Carboniferous to the late Middle Permian. Sediments are located at the top of the seafloor, the upper wing, the lower wing and the base. The sediments on the ocean floor are reef limestone, acicular chert limestone, acicular chert limestone , Radioactive worm chert; each set of rocks are located above the greenstone. Radiolarian chert is more distal than acicular flint. These rock masses are deposited on and around the basaltic seamounts formed in open sea without the entry of terrestrial matter.