Objective Quantitative acquisition of the activity rate of strike slip faults in geological history is the basis of continental dynamics research, and also an important support for understanding the deformation mechanism of lithosphere and its dynamic evolution process over time. Obtaining accurate quantitative results mainly depends on the study of the existing and residual dislocation geomorphic indicators. At present, most studies mainly use the characteristic geological bodies that are dislocated along the two sides of the strike slip fault to limit the horizontal displacement of ten kilometers to one hundred kilometers, while the younger geomorphic units are used to limit the small displacement of meters to one hundred meters since the late Quaternary. However, studies on kilometer−scale fault displacements, which lie between these two extremes, are relatively scarce.
Methods This paper attempts to use Sentinel−2B multispectral image data, adopting an image enhancement processing technique fusing specific band data, and geological mapping results in the middle east section of the Altyn Tagh fault zone to accurately limit the horizontal displacement of ten meters to kilometers in the west of Heping town and the east of Shibaocheng town in two survey areas, which are about 50~130 m and 3~5 km, respectively.
Results According to the existing stratigraphic age, the estimated fault slip rate is 11.8 mm/a and 1.2~5.7 mm/a, respectively.
Conclusions It is basically consistent with the ten thousand years scale active tectonic rate and the ten−year scale current deformation rate obtained by predecessors, which provides a new solution for the next step to determine the accurate long−term scale fault slip rate in combination with sediment source analysis and appropriate Chronology testing methods, and improve the activity history of strike slip faults since Quaternary.
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