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西秦岭海西-印支期成矿大地构造背景为受位于古特提斯洋的坳拉槽,主要依据:(1)地层呈东宽西窄的剪刀形,犹如古特提斯构造带伸进中国古陆内的一段盲肠,并且位于中国古陆的凹入部位;(2)主要发育海相槽台沉积,且发育时限漫长,对应于古特提斯大约从4亿至2亿年的演化时限;(3)发育同沉积断裂,特别是同沉积正断层为主要的控相构造;(4)变质程度低,侵入岩及火山岩发育较少,并且火山作用西强东弱。这一认识对研究秦岭地质构造关键性问题得到较合理的解释。推断其主要构造型式为一具有向南倾主滑脱面的半地堑,是层控、热水沉积和浅成热液型铅、锌、金、银、汞、锑等矿产成矿的有利构造环境。
The western Qinling Hercynian-Indosinian metallogenetic tectonic setting is dominated by the aulacool groove located in the ancient Tethys Ocean. It is mainly based on: (1) The strata show a scissors shape with a narrow width of the east, the west and the west, Into a section of cecum within the ancient Chinese mainland, and is located in the concave part of the ancient Chinese continent; (2) the main development of marine sediments, and the long development time, corresponding to the ancient Tethys about 400 million to 200 million years Evolutionary time limit; (3) the development of synsedimentary faults, especially the synsedimentary normal faults as the main controlled facies structure; (4) low metamorphism, intrusive rocks and volcanic rocks less developed, and the volcanism is stronger in the west and weaker in the east. This understanding of the Qinling Geological Structure of the key issues to be more reasonable explanation. It is inferred that the main structural type is a semi-graben with south-facing main slip surface, which is a favorable structure for stratigraphic control, hydrothermal deposition and mineralization of epithermal lead, zinc, gold, silver, mercury and antimony surroundings.