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北祁连早古生代洋盆是裂陷槽还是大洋盆,是一个有争论的问题。文中讨论了蛇绿岩中保存的代表大洋盆存在的印记。认为被夹持于华北地块和柴达木地块之间的北祁连早古生代造山带属于板块增生杂岩带,是由海洋岩石圈残片、消减杂岩、岛弧增生楔等组成的(或许还包括一部分残留陆块)。指出北祁连蛇绿岩属于科迪勒拉型,暗示北祁连在早古生代时可能曾经是一个规模较大的洋盆,而非裂陷槽。华北地块和柴达木地块的规模很小,只不过是浩瀚海洋中散布的微小陆块而已。
The pre-Paleozoic oceanic basins in North Qilian are either rift troughs or oceanic basins. This is a controversial issue. The paper discusses the imprint that represents the existence of the oceanic basin preserved in ophiolite. It is considered that the Paleozoic orogenic Paleozoic orogenic belts in North Qilian between North China block and Qaidam block belong to plate accretionary complex belt and are composed of marine lithospheric fragments, depleted complexes and island arc accretion wedges Perhaps including part of the remaining land). It is pointed out that the North Qilian ophiolite belongs to Cordillera type, suggesting that the North Qilian might have been a large oceanic basin rather than a rift basin during the Early Paleozoic. North China block and Qaidam plots of small size, but the tiny ocean scattered in the vast land only.