【摘要】 利用1999—2007年、2011—2013年的流动GNSS观测资料及处理结果,分析了2013年吉林松原MS5.8地震前区域水平形变场及其变化,获得以下结果:1松原MS5.8级地震发生在地壳运动相对较弱的部位;2发震区带1999—2007年主应变和最大剪切应变几乎为零,为全区应变最薄弱的部位,2011—2013年仍然相对较弱;3发震区带1999—2007年为右旋形变区带,2011—2013年为左右旋形变的转换区带,但量级均较弱;4 1999—2007年发震区形变均较小,在性质上以微弱的右旋形变为优势;2011—2013年全区形变率大于之前,在性质上以左旋形变为优势,较大运动部位大体上以震中为中心且平行于北郯庐断裂以东的区域,这样的变化主要来自于日本9.0级大震的震后调整,但似乎不是导致松原地震发生的诱因。更多还原

【Abstract】 We used mobile GNSS observations of 1999—2007and 2007—2013and their processing results,and analyzed the horizontal deformation field and its changes before the November 23,2013 Songyuan MS5.8earthquake in Jilin province.The results show that(1)The Songyuan MS5.8earthquake occurred in the region of weaker crust movement;(2)The maximum shear strain and main principal strain of this earthquake zone are almost zero in 1999—2007,which is the weakest part in the region,and still weaker in 2009—2013;(3)The earthquake zone is right rotary deformation in 1999—2007,and is transition zone for the left and right rotary deformation in 2009—2013,both of their order are weaker;(4)Crustal deformation is smaller and right rotary deformation is primary in whole area from 1999 to 2007;however,it is larger in east part of the area and left rotary deformation is primary in the area between 2009 and 2013.We think that the change is caused by the Japan MW9.0earthquake,but Songyuan earthquake is not occasioned by the MW9.0earthquake.更多还原