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从我们科考四分队所获得的资料表明,全区的构造格架可以班公错断裂和噶尔曲断裂为界划分为三个构造带,从北到南为:喀喇昆仑构造带,冈底斯构造带、喜马拉雅构造带。(图1)它们是呈北西或北西西方向展布。在喀喇昆仑构造带,主要发育的地层为上石炭统一侏罗系,有复理石夹基性火山岩,沿班公错断裂有属于印支运动的中酸性小侵入体。班公错西段有超镁铁岩小岩体。说明在这个带的南部,中生代以来岩浆活动是较弱的。冈底斯构造带,发育有白垩系和第三系。白垩系下部碎屑岩中含有蕨类和苏铁等植物化石,可能代表滨海环境。上部为浅海环境形成的礁状灰岩。第三系为碎屑岩系,在门士附近有含煤地层。冈底斯构造带内,由于班公错断裂与噶尔曲断裂交汇形成三角形地带,并产生一系列北西向的断裂和褶皱,控制了燕山运动的中酸性岩浆活动和超镁铁岩及有关火山岩的分布。冈底斯构造带的南部为喜马拉雅构造带的西北段,与冈底斯构造带相比,有酸性岩浆侵
The data obtained from our expedition Corps 4 shows that the tectonic framework of the entire region can be divided into three tectonic belts by dividing the Banggong fault and the Gallsean fault into three tectonic belts, from north to south: the Karakorum tectonic belt, The end of the structural belt, Himalayan tectonic belt. (Figure 1) They are spread northwest or north west. In the Karakorum tectonic belt, the major strata are the Upper Carboniferous Jurassic, with flysch-bedded volcanic rocks and small to medium-sized intrusions belonging to the Indosinian movement along the Gonggong fault. Ban Gongshe western section of ultramafic rock small rock mass. It shows that magmatism was weak in the southern part of this belt since Mesozoic. Gangdise structural belt, the development of the Cretaceous and Tertiary. Lower Cretaceous clastic rocks contain ferns and cycads and other plant fossils, may represent the coastal environment. Upper reef-shaped limestone formed by the shallow sea environment. The Tertiary is a clastic rock system with coal-bearing strata near Menhye. In the Gangdese tectonic belt, due to the intersection of the Bancongzao fault and the Gulchu fault, a triangular zone is formed and a series of NW-trending faults and folds are produced to control the moderate-acid magmatism and ultramafic rocks of the Yanshan movement and related volcanic rocks Distribution. The southern Gangdese tectonic belt is the northwestern segment of the Himalayan tectonic belt. Compared with the Gangdese tectonic belt, there are acidic magmatic intrusions