选取晋冀蒙交界地区2014年10月-2015年8月ML 2.0以上地震事件，使用SAM软件进行S波分裂，得到研究时空域内S波分裂的偏振方向和延迟时间。其中：偏振方向在晋冀蒙交界的和林格尔以南及大同盆地、天镇-阳高盆地、阳原盆地和浑源盆地周围区域存在较大幅度变化；延迟时间变化范围在0.01-0.08 s，主要集中在0.01-0.03 s，高值主要出现在恒山南麓断裂和怀安盆地南缘断裂附近。分析认为，晋冀蒙交界地区地下介质各向异性较复杂，需密切注意今后地震地质活动。
In this paper, by use of the data of ML 2.0 seismic events recorded by 39 mobile stations and four fixed stations in the border region of Shanxi, Hebei and Inner Mongolia (38.5°-40.7°N, 111.1°-115.6°E) from October 2014 to August 2015, and with SAM software for the S wave splitting study, the S wave polarization direction and the delay time in time and space domain has been investigated. The results show that there is a substantial change of the direction of polarization at the junction of Shanxi, Hebei and Inner Mongolia and Lingle Saharan region and Datong Basin, Tianzhen-Yanggao Basin, Yangyuan basin and surrounding areas of Hunyuan basin; the change amplitude of the delay time is in the scope of 0.01-0.08 seconds; the high value are mainly concentrated in the 0.01-0.03 seconds; and a high value occurs mainly near the Huai basin to the southern edge of the fault rupture and south of Hengshan. According to the results obtained here, it is thought that the subsurface anisotropy in the border area of Shanxi, Hebei and Inner Mongolia is more complex, and is necessary to pay close attention to the future seismic geological activity in there.
2017,38(1): 15-20 收稿日期：2016-04-15
DOI：10.3969/j.issn.1003-3246.2017.01.003
基金项目：中国地震局科技星火计划青年项目（编号：XH15009Y）
作者简介：张晖(1982-),男,毕业于中国地震局兰州地震研究所,硕士研究生,工程师,从事地震监测预报工作。E-mail:zhandyg@163.com
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