Tectonic Deformation Characteristics And Its Control On Mineral Resources In Cuomei Area,Southern Tibet

The Himalayan Orogenic Belt is the youngest and most typical orogenic belt in the world.It was formed by collisions between the Indian plate and the Asian continent during the period of 70-50 Ma.Since the collision,the Himalayan orogens have significantly shortened the crust.After entering the Miocene,the Himalayan orogenic belt has undergone a large stretch and detachment movement while the crust has shortened and thickened.The tectonic evolution process has formed a complex geological structure in southern Tibet.At the same time,the collisional orogeny was accompanied by a large number of magmatic intrusions,which provided favorable conditions for the formation of antimony?gold?lead and zinc polymetallic deposits in southern Tibet,making the area a favorable area for the formation of antimony,gold and other minerals.Cuomei area is located in the first grade tectonic units in Himalaya orogenic system in Himalaya area.In the study area,the fault structures extend eastward to west and south to north,and antimony gold deposits are distributed.During the field,through field geological observation,we saw plenty of geological phenomena.Through the analysis and study,the fracture of the study area is divided into brittle fracture and ductile fracture,and the structural evolution of the region is divided by the analysis of the mechanical analysis and the achievements of the previous work.On the whole,the tectonic evolution of the region is divided into six stages,which are as follows:(1)the Cenozoic Paleogene was squeezed by NE-SW to form a ductile thrust belt;(2)the Neocene Mesozoic and Neocene tensional stretching was formed by the Neocene;(3)the Miocene was squeezed by NE-SW,and a steep cleavage was developed in the sandstone and diabase rocks.The section has calcite vein filling;(4)the middle Miocene was squeezed by NW-SE,forming folds,joints and reverse faults,reverse faults and dextral properties;(5)the middle Miocene was squeezed by NNW-SSE,forming brittle reverse faults,shear joints,quartz veins filling,and the reverse fault with left-handed property;(6)Quaternary due to the shortening and thickening of the earth's crust,tensile stress occurs,and a series of high-angle normal faults and soft rock formations slide northward along the sandstone,limestone,and diabase.Through the analysis and study of the structural features in the region of the Cuomei area,and combining the genesis and metallogenic regularity of the deposit in the study area,it is speculated that the faulted structures in the study area may provide a space for metallogenesis and accumulation,while the magmatic intrusion may affect the ore-forming materials.The source has a certain positive effect and provides the impetus for the migration of ore-forming fluids.