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采用7条地震前后日本ALOS/PALSAR整轨数据,利用D-InSAR技术提取了2008年5月12日四川汶川地震500km×450km的地表连续同震形变场。形变场覆盖了金川—石棉、黑水—乐山、松盘—彭山、南坪—简阳、康县—重庆所有区域,包括了理县、汶川、茂县、北川、青川等重灾区域。结果显示,整个形变场影响范围较大,四川盆地出现了不同程度的地表形变。发震断层附近的非相干区域显示此次地震地表主破裂带在北川-映秀断裂带上,可以追踪出地表破裂带从汶川县映秀镇西南震中附近一直到青川县苏河北侧,全长约为230km。在发震断层西南段汶川至茂县一带,非相干条带的宽度明显大于其它段落,这与彭县-灌县断裂(前山断裂)的都江堰—安县段地表破裂段密切相关,地表破裂带长约70km。在远离发震断层的区域,西北盘总体表现为抬升,东南盘表现为沉降。但在发震断层附近,断层两侧均表现为局部抬升,且沿断层形变量分布很不均匀,表现出较强的分段性,显示出发震断层以逆冲为主的断层性质。从美国哈佛大学(Harvard)、美国地质调查局(USGS)与美国国家地震信息中心(NEIC)、中国地震台网中心(CENC)所给出的震中位置和发震时刻的差异来看,也反映出汶川地震破裂过程是多点破裂过程。在汶川县映秀镇西侧震中区,最大相对形变量达260cm,如果全部换算成垂直形变,则两个区域的垂直相对形变达3.3m。在雅安、峨眉山一带约有35cm的沉降区,在重庆及其南侧区域约有25cm的小范围隆起。
Based on the data of Japan ALOS / PALSAR orbit before and after 7 earthquakes, the continuous coseismic deformation field of 500km × 450km on Wenchuan Earthquake on May 12, 2008 was extracted by D-InSAR technique. The deformation field covered all the areas of Jinchuan - asbestos, Heishui - Leshan, Songpan - Pengshan, Nanping - Jianyang and Kangxian - Chongqing, including heavily damaged areas such as Li County, Wenchuan, Mao County, Beichuan and Qingchuan. The results show that the whole deformation field has a wide range of influence, and different degrees of surface deformation have occurred in the Sichuan Basin. Non-coherent areas near the seismogenic faults show that the main rupture of the earthquakes on the Beichuan-Yingxiu fault zone can trace the surface rupture zone from the vicinity of the southwest epicenter of Yingxiu town in Wenchuan County to the north of Suhe in Qingchuan County with a total length of about 230km. In the area from Wenchuan to Maomao County in the southwestern segment of the seismogenic fault, the width of the incoherent strip is significantly larger than that of the other segments, which is closely related to the surface rupture of Dujiangyan-Anxian section of Pengxian-Guanxian fault (Qianshan fault). The length of the surface rupture zone 70km. In the area far away from the seismogenic fault, the overall performance of the northwest plate is uplifted while that of the southeast plate shows settlement. However, in the vicinity of the seismogenic fault, both sides of the fault show partial uplift, and the distribution along the fault is very uneven. It shows a strong segmentality and shows the fault-type faults that are mainly thrusted. The differences between epicenter locations and seismogenic moments given by Harvard, USGS and NEIC and CENC are also reflected The Wenchuan earthquake rupture process is a multi-point rupture process. In the epicenter of the west of Yingxiu town in Wenchuan County, the maximum relative deformation is 260cm. If all are converted into vertical deformation, the vertical relative deformation of the two areas reaches 3.3m. In Ya’an, Emeishan area about 35cm of settlement, in Chongqing and its southern region about 25cm uplift in a small area.