CAJ | 학술논문

利用1999-2007年和2009-2013年两期 GPS 速度场资料，采用最小二乘配置方法分别计算了2008年和2014年新疆两次于田 MS 7．3地震前新疆及周边地区的主应变率、面应变率及最大剪应变率，分析了该区域的变形动态特征，并结合速度剖面分析方法给出了震源区的构造变形特征．速度场及应变率场动态结果表明：新疆天山地区的地壳变形特征整体表现为由南向北缩短，相对运动速率表现为由南向北、由西向东逐渐减小；震源区东侧的左旋剪切变形明显大于西侧；2008年与2014年两次于田 MS 7．3地震的震源区均处于拉张与挤压变形的过渡地带，易于强地震的发生；2008年于田 MS 7．3地震的张性兼有少量剪性破裂的发生使得阿尔金断裂的左旋剪切变形增强．GPS 速度场剖面分析结果表明，2014年于田 MS 7．3地震前震源区西侧的变形宽度大于东侧，剪切应变积累程度西侧高于东侧．综合分析认为，震源周边构造区应变积累的差异性有利于强震的孕育，2008年于田 MS 7．3地震对2014年于田 MS 7．3地震可能有促进作用．
이용1999-2007년화2009-2013년량기 GPS 속도장자료，채용최소이승배치방법분별계산료2008년화2014년신강량차우전 MS 7．3지진전신강급주변지구적주응변솔、면응변솔급최대전응변솔，분석료해구역적변형동태특정，병결합속도부면분석방법급출료진원구적구조변형특정．속도장급응변솔장동태결과표명：신강천산지구적지각변형특정정체표현위유남향북축단，상대운동속솔표현위유남향북、유서향동축점감소；진원구동측적좌선전절변형명현대우서측；2008년여2014년량차우전 MS 7．3지진적진원구균처우랍장여제압변형적과도지대，역우강지진적발생；2008년우전 MS 7．3지진적장성겸유소량전성파렬적발생사득아이금단렬적좌선전절변형증강．GPS 속도장부면분석결과표명，2014년우전 MS 7．3지진전진원구서측적변형관도대우동측，전절응변적루정도서측고우동측．종합분석인위，진원주변구조구응변적루적차이성유리우강진적잉육，2008년우전 MS 7．3지진대2014년우전 MS 7．3지진가능유촉진작용．
This paper calculates the principal strain rate,plane strain rate and maximum shear strain rate in Xinjiang and its vicinity by using the least squares method with GPS data set during 1999-2007 and 2009-2013.The crustal tectonic deformation characteristics in this area before 2008 and 2014 Yutian MS 7.3 earthquakes are also analyzed comprehensively.The dynamic results of velocity field and strain rate field indicate that the crust shortening decreases gradually from south to north and from west to east,suggesting that the sinis-tral shear deformation in the eastern side is significantly greater than that in the western side around focal area.The source areas of 2008 and 2014 MS 7.3 Yu-tian earthquakes are located in the transitional zone of the tensile and compres-sive deformation,which is prone to occurrence of a great earthquake.The sur-face rupture in 2008 Yutian earthquake,which is mainly tensile with little shear component,strengthened the sinistral shear deformation of Altyn Tagh fault. The GPS velocity profiles show that the deformation width of western side is greater than that of the east in the hypocentral region before 2014 Yutian MS 7.3 earthquake,consistent with the degree of shear strain accumulation.In conclu-sion,this difference between two sides in strain accumulation are easy for the nucleation process of 2014 Yutian earthquake.And it is inferred that the 2008 Yutian MS 7.3 earthquake may play a role in promoting the 2014 Yutian MS 7.3 earthquake.