【摘要】 <正> 强震的孕育和发生,与区域构造活动的强度和方式密切相关,不同地区各自特点不同。本文综合近年活断层填图等方面研究成果,对山西断陷带7级以上历史强震的地表破裂带及全新世古地震进行分析对比,讨论该区7级以上强震地表破裂特征。强震发生时,依据当地的地形地物条件,破坏区的地表出现多样地面破坏现象,例如山崩、滑坡、地裂缝、地表陡坎、喷砂冒水等。在松散沉积物地区,许多地表破坏现象常反映震时的应力场特征。本文着重讨论的是震时出现的反映震源发震构造特征的地表破坏现象——地表破裂带、地表地震断层或地震形变带。更多还原

【Abstract】 The Shanxi Fault-Depression Zone is one of the major seismical active zones in China.According to historical records,there have been six large events occurred in the zone with magnitude greater than 7,and one of which reached 8.Recently,some new discoveries on the Holocene paleo-earthquakes have been reported.The authors tend to review these new achievements and discuss the characteristics of surface ruptures and their correlation with the magnitude of earthquake that formed such surface rupture. The conclusions are as fellows: 1. Paleo-seismological studies proved that in the passed several thousand years, strong earthquakes had occurred in all the major basins in the fault-depression zone from north to south; and that these basins have close relation with strong earthquakes, as they act as an integrated tectonic system. 2. The Holocene paleo-earthquakes were featured as characteristic earthquakes. 3. Co-seismic surface rupture belts of some historical and paleo-earthquakes can be discontiguous and the discontinuance may reach 15～25 km, 20%～30% of the total length of the surface rupture belt. 4. The recurrence interval of 3 historical events with M7 in the Xinding basin was 500～650 a. That of another two events occurred in the Linfen basin was less than 400a. Each of the two basins has 2-3 active faults. The point is that the above-mentioned recurrence interval of each basin is much shorter than the recurrence interval of strong earthquakes on each active fault in the basin. This may imply that the interaction of the active faults in the whole interacted tectonic unit.更多还原