抄録
Tarim Basin, Xinjiang Uyghr autonomous region, China, contacts with the Tian Shan and the Pamir at its northwestern corner. On the tectonic field, Tarim Basin is considered to be under thrusting into the Tian Shan from south and the Pamir is slipping left-lateral against the Tarim Basin. Recently, many earthquakes have occurred in this region, including the Artux earthquake of 1902 (Magnitude 8 1/4) and the Wugia earthquake of August in 1985 (Magnitude 7.5). Though these major earthquakes are caused by the active faults, the precise locations of these active faults, with some references and characteristics of their activities are obscure. The purpose of this paper is to show the distribution and characteristics of the active faults at the northwestern corner of Tarim Basin based on the interpretation of the CORONA Satellite Photographs. The following results were obtained:
Active faults of this region, mainly based on the reference of the river terraces, can be classified into following two groups; a) the reverse faults in SW-NE direction of parallel with the Tian Shan, b) the reverse faults parallel with the King Ata Tagh, located along the northeastern piedmont of the Pamir. The latter group changes their direction from N-S to NW-SE into the North. Based on the directions of the above mentioned active faults and occurrences of the major earthquakes (Magnitude>7.5) amidst these active fault zones, these active faults are considered to be forming important boundaries both of the Tarim Basin to the Tian Shan and to the King Ata Tagh, namely to the Pamir.
According to the seismic data of USGS National Earthquake Information Center, recent earthquakes in the past 30 years concentrate around the southern part of Wugia and the northern part of Wpaerh. In the other areas along these recognized active faults, obviously, few earthquakes have occurred. If there is no evidence of large earthquakes during the historical time in the other areas, these active faults have high potentials for the occurrences of the large earthquakes in near future.
It is necessary for more detailed investigations, namely, on the last events, amount of dislocations and the activity intervals of these active faults, for not only understanding the kinematics of present deformations of the Tian Shan, the Tarim Basin and the Pamir, but also the prevention of earthquake disasters.
