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基于黄河源区1∶25万生态环境地质调查新获得的大量实际资料,通过分析和研究发现,黄河源区早更新世—中更新世处于走滑伸展的大陆动力学背景,在整体隆升中,形成断块山与拉分盆地,湖泊广布;晚更新世,大陆动力学机制过渡为挤压收缩,在整体抬升中,断块山显著崛起,湖盆萎缩、变形;全新世,大陆动力学环境反转为走滑挤压,持续隆升,黄河扩展源头到达本区,扎陵湖、鄂陵湖外泄,闭流盆地水环境转向开放。近代,特别是20世纪70年代以来,新构造活化与寒冻风化岩屑坡扩大、沙质荒漠化蔓延、湖泊和沼泽湿地萎缩、区域地下水位下降、源区黄河频繁断流、生态环境日益恶化响应关系密切。因此,新构造运动在黄河源区生态环境恶化中起主导作用,而其他因素则起到促进与加速的作用。
Based on a large amount of actual data obtained from 1: 250000 eco-environmental geological survey in the source region of the Yellow River, it was found through analysis and research that the Early Pleistocene-Middle Pleistocene in the source region of the Yellow River was in continental dynamics of strike-slip extension. During the whole uplift During the Late Pleistocene, the continental dynamic mechanism was changed to squeeze and shrinkage. During the whole uplift, the fault block mountain rose sharply, and the lake basin shrank and deformed. During the Holocene and the mainland, The environment was reversed for the strike-slip extrusion and continued uplift. The Yellow River extended its source to reach the area. The Zaling Lake and Eling Lake leaked and the water environment in the closure basins turned to open. In modern times, especially since the 1970s, the lithosphere slope of neotectonic activation and freezing weathering has been expanded, sandy desertification has spread, lakes and swamps have been shrunk, the regional groundwater table has been declining, and the Yellow River in the source area has been cut off frequently, deteriorating the ecological environment. Close relationship. Therefore, the neotectonic movement played a leading role in the deterioration of the ecological environment in the source region of the Yellow River, while other factors played the role of promotion and acceleration.