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给出了通过对2005~2012年期间发生的约10万个地震改进震源定位获得的意大利仪器记录的地震活动性的一幅新图像。改进的定位对地中海中部地区的活动构造产生了新的约束,该地区的嵌套板块和大陆碎片之间长期的相互作用导致了阿尔卑斯和亚平宁山系的发育。中源和深源地震确定了此山脉带下面分层的横向非均匀过程以及大陆岩石层下沉的活跃。浅源地震主要发生在抬升的地形下且与低速地幔异常有关,表明重力的叠加迫使欧亚—非洲板块汇聚。分层过程驱动使山脉拉长,同时导致山脉外边缘缩短的挤压和扩张结对体系。更新的地震目录使我们能解决近年来即2009年MW6.3拉奎拉地震后出现的地震活动率的突变。由于地壳内流体流动和孔隙压力变化引起应力场的区域尺度扰动,该扰动可能与山脉下方深部脱水过程的活跃有关,因此,地震活动率的增加是合理的。
A new image of the seismic activity recorded by an Italian instrument obtained through improved source localization of about 100,000 earthquakes that occurred during 2005-2012 was presented. Improved positioning has created new constraints on the tectonics of the Central Mediterranean, where the long-term interaction between the nested blocks and the continental fragments led to the development of the Alps and the Apennines. The mid-source and deep-source earthquakes have determined the lateral heterogeneity of stratification beneath this mountain range and the subsidence of the continental lithosphere. Shallow source earthquakes occur mainly under the uplifted terrain and are associated with low-velocity mantle anomalies, indicating that the superimposition of gravity forces the Eurasian-African plate to converge. Stratification drives the extrusion and dilatation systems that stretch the mountains and shorten the outer edges of the mountains. The updated earthquake catalog enables us to address the abrupt change in seismic activity that occurred in recent years after the MW6.3 Aquila earthquake in 2009. Because of the regional scale perturbation of stress field caused by fluid flow and pore pressure changes in the crust, the disturbance may be related to the activity of deep dehydration process below the mountain range. Therefore, the increase of seismic activity rate is reasonable.