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中国东部构造演化,自1200Ma以来曾发生过两次碰撞、三次裂解。并有向东增生的构造岩浆地体。资料表明:①从中国大陆向东至日本、台湾均为人陆型地壳;②中国东部及西太平洋大陆板块的各微板块之间地壳结构不同;③裂解带的形成是由于热点和地幔对流导致大陆解体;④裂解带均显示出高重力正异常,上地幔顶部波速低、具低速层、高热流区的“裂谷垫”性质;⑤增生的构造岩浆地体同位素组成、微量元素与洋中脊玄武岩的性质有较大差异,裂解带的岩浆为大陆地幔的特征;⑥上地幔特征及岩浆分融、分异均显示出横向不连续。也显示山化学边界层和热边界层的不连续。
Tectonic evolution in eastern China has seen two collisions and three cleavages since 1200 Ma. There is a tectonic magmatic land that is accreted to the east. The data show that: ① from the Chinese mainland to the east, Japan and Taiwan are all human-type land crusts; ② crustal structures are different between the microplates in the eastern China and the western Pacific continental plates; ③ the formation of the lytic belt is caused by the hot spots and the convection of the mantle, (4) the pyramidal zone shows the features of high gravity positive anomalies, low ripple velocity at the top of the upper mantle, and the “rift mats” of low-velocity and high-heat flux areas; (5) the isotopic composition of the accretionary tectonic magmatism, trace elements and mid- The characteristics of the basalt are quite different. The magma in the tectonic zone is characteristic of the continental mantle. (6) The characteristics of the upper mantle and the differentiation and differentiation of the magma show lateral discontinuities. The discontinuities of the mountain chemical and thermal boundary layers are also shown.