可可西里古近系含盐系地层沉积特征及古盐湖成盐模式讨论

Discussion on Sedimentary Characteristics of the Paleogene Salt-bearing Formation and Saltforming Model of the Paleo-Saline in Hoh Xil Area

中文关键词:  含盐系地层  沉积特征  成盐模式  盐湖封闭性  古近系  可可西里

英文关键词:Salt-bearing formation  Sedimentary characteristics  Saltforming model  Sealing of paleo-saline  Paleogene  Hob Xil

中文摘要:

      可可西里是羌北-滇西构造域中重要的新生代沉积盆地，其古近系红层是认识中国陆相微陆块成盐作用的重要窗口。该区南部沱沱河盆地、北部错仁德加盆地古近系雅西措群地层中明显包含两套含盐系地层，两套层系形成的时代、古气候条件相同，但古地理条件、古盐湖盆地规模、成盐机制各异。渐新世时期沱沱河盆地属于封闭型的干盐湖沉积。错仁德加盆地属于开放型干盐湖沉积环境，预示着青藏高原中部渐新世大可可西里盆地并非相互连通，其中小型盆地的沉积成盐环境存在差异。

英文摘要:

      The Hoh xil area is the most impotant sedimentary basin in the tectonic domain of Qiangtang-- West Yunnan in Cenozoic. That has been called red-layer or gypsum-salt bed is very wide distribution in this area, it gives us a bright window to the salt-forming mechanism of continental palaeo-block. Taking sedimentology and paleogeographic analysis as guiding theory, focusing on Yaxicuo formation in Oligocene, selecting Cuorendejia（CRDJ） basin and Tuotuohe （TTH） basin in Hoh Xil area as the main re- search object, two salt-beating series could be recognized. Comprehensive evaluation revealed that both of the salt-bearlng series formed in the same period and paleoclimate, but there are different palaeogeo- graphical conditions, different scale of the Paleo-Saline and salt-forming mechanism for the two secondary salt basins, The CRDJ basin was an opening playa, while the TTH basin was more closed, implay that the wide Hoh Xil area was consisted by a series of distinctive, secondary salt basins.