摘要
Finite strain patterns of rocks The structural styles and crustal shortening in the northern margin of Qinghai—Tibet plateau are examined by systematic finite strain measurements. The finite strain patterns in this area are of following characteristics:① The orientation of & principal axes of strain ellipsoid varies regularly in regard to different tectonic locations. In fact, most of the measured X axes are parallel to the regional structure lines, striking east\|west or approximately east\|west with some X axes trending northeast\|southwest. The measured Z\|axes are approximately at right angle to the regional structure lines, trending north\|northeast or north\|northwest.② The Flinn parameter k is higher in the northern and southern margins of the basin than that in the basin center, indicating that the margins of basin experienced extensional strain and the middle of basin undergo strain.③ Rocks of different age possess different strain state and show k value of 1～2 for Tertiary rocks, 3～4 for Jurassic—Cretaceous rocks. The k value of the basement rocks is the highest of all.
Finite strain patterns of rocks The structural styles and crustal shortening in the northern margin of Qinghai—Tibet plateau are examined by systematic finite strain measurements. The finite strain patterns in this area are of following characteristics:① The orientation of & principal axes of strain ellipsoid varies regularly in regard to different tectonic locations. In fact, most of the measured X axes are parallel to the regional structure lines, striking east\|west or approximately east\|west with some X axes trending northeast\|southwest. The measured Z\|axes are approximately at right angle to the regional structure lines, trending north\|northeast or north\|northwest.② The Flinn parameter k is higher in the northern and southern margins of the basin than that in the basin center, indicating that the margins of basin experienced extensional strain and the middle of basin undergo strain.③ Rocks of different age possess different strain state and show k value of 1～2 for Tertiary rocks, 3～4 for Jurassic—Cretaceous rocks. The k value of the basement rocks is the highest of all.
出处
《地学前缘》
EI
CAS
CSCD
2000年第S1期149-150,共2页
Earth Science Frontiers
