利用GPS数据研究低纬度环球剪切带的活动性

AN ANALYSIS OF FAULT ACTIVITY IN SHEAR ZONE AT LOW LATITUDES FROM GPS MEASUREMENTS

利用GPS速度研究了低纬度环球剪切带主要断裂的活动性,结果显示:北安纳托利亚断裂、北高加索断裂、嘉黎断裂、实皆断裂以及苏门答腊断裂均表现为右旋走滑特征,滑动速率分别为13.7±0.6、5.8±0.5、7.1±1.0、12.7±0.2和25.4±0.5 mm/a;索龙断裂和危地马拉断裂呈现左旋走滑特征,滑动速率分别为29.2±1.8、14.1±1.0 mm/a;嘉黎断裂和苏门答腊断裂表现出强挤压性,挤压量分别为18.5±1.0、15.2±0.6 mm/a;索龙断裂表现出强拉张性,拉张量为10.7±1.1 mm/a。低纬度剪切带总体上表现出较强的活动性并以剪切活动为主。

Global Positioning System （GPS） measure campaign in shear zone at low-latitudes was conducted in 1991 and 2003, for quantifying the present-day major faults＇ activity. The results are as follow, the north Antolia fault , Jiali fault, Sagaing fault and Sumatra fault are right lateral motion, the rates are（ 13.7 ± 0.6 ）, （5.8 ± 0.5 ） （7.1± 1.0）, （ 12.7 ±0.2） and（25.4± 0.5 ） mm/a respectively; while the Sorong fault and Guatemala fault are left lateral motion , the rates are 29.2 ± 1.8）, （ 14.1±1.0） mm/a, respectively . Besides, Sumatra fault and Jiali fault also show strong squeezing, （18.5 ± 1.0）, （15.2 ±0.6） mm / a, respectively, while Sorong fault show powerful pull, reached to ： （ 10.7 ± 1.1 ） mm / a. Overall, the shear activity dominats in the shear zone at low-latitudes.