摘要
The intensive geophysical survey of Qinghai Lake reveals the buried depth of lake sediments and their distribution features. The result indicates that there are three important inter- phases of Qinghai Lake sediments: T1 is the rife interphase of the lake, above which sediments are spread all over the lake basin with roughly the same thickness; T5 is the interphase from which the neotectonic sedimentary cycle begins, and its above sedimentary environment is relatively stable; Tg is the base of the lake basin. Five west-northwest (WNW) fault belts defined the tectonic structure of Qinghai Lake basin: the central hunch around Haixin Shan with two subbasins both in its north and south. The thickness of the lake sediments varies at different places, the thickest sediments are found within the two subbasins. According to the depth that the Sparker System can reach, sediment in the northern subbasin is deeper than 560 m, while sediment in the southern subbasin is deeper than 700 m. The correlation between the seismic sequence stratigraph and the lithology of onshore core shows that Qinghai Lake sediments consist of muddy silt, clay silt, silty clay, gravel silty clay, etc.
The intensive geophysical survey of Qinghai Lake reveals the buried depth oflake sediments and their distribution features. The result indicates that there are three importantinter-phases of Qinghai Lake sediments: T1 is the rife interphase of the lake, above which sedimentsare spread all over the lake basin with roughly the same thickness; T5 is the interphase from whichthe neotectonic sedimentary cycle begins, and its above sedimentary environment is relativelystable; Tg is the base of the lake basin. Five west-northwest (WNW) fault belts defined the tectonicstructure of Qinghai Lake basin: the central hunch around Haixin Shan with two subbasins both inits north and south. The thickness of the lake sediments varies at different places, the thickestsediments are found within the two subbasins. According to the depth that the Sparker System canreach, sediment in the northern subbasin is deeper than 560 m, while sediment in the southernsubbasin is deeper than 700 m. The correlation between the seismic sequence stratigraph and thelithology of onshore core shows that Qinghai Lake sediments consist of muddy silt, clay silt, siltyclay, gravel silty clay, etc.
作者
AN Zhisheng1, WANG Ping2, SHEN Ji3, ZHANG Yixiang2, ZHANG Peizhen4, WANG Sumin3, LI Xiaoqiang1, SUN Qianli1, SONG Yougui1, AI Li1, ZHANG Yechun2, JIANG Shaoren2, LIU Xingqi3 & WANG Yong31. Institute of Earth Environment, Chinese Academy of Sciences (CAS), Xi’an 710075, China
2. South China Sea Institute of Oceanology, CAS, Guangzhou 510301, China
3. Nanjing Institute of Geography and Limnology, CAS, Nanjing 210008, China
4. Institute of Geology, China Earthquake Administration, Beijing 100029, China
