关键词: 羌塘地区, 地壳, 低电阻, 地层

Abstract: The inner-crustal low resistivity zones over the profile of crustal magneto-electrotelluric survey beneath 100 km in Qiangtang area show district images which are characterized by massive body symbolided as“△”in southern segment and tremendous mushroom body in northern segment ranging from-100 km up to-10 km in depth. From the view of plane contour diagram, the northern Qiangtang area is characterized by large area of depression-uplift and bulking in its east and west parts, while the southern Qiangtang area by strip depression-uplift and zoning in its south and north parts. The results show that the low resistivity zone is related closely to the landscapes, not only indicating reliability about the zone interpretation,but that the distinctive features like block high mountain range are expressions of active deep tectonic movements. The crustal bodies in studied area are neither cold nor thermal, but cold crust alternates with thermal crust in form of wedge,,along the Quedancuo area may exist thermal plume,all of which has greater effect on its petroleum accumulation, generation and secondary origin.

Key words: Qiangtang area, crust, Low resistivity, formation