对1556年84/级大地震震中位置和发震构造的新认识

The New Recognizes for Epicenter Location and Seismogenic Structure of 1556 M 84/ Large Earthquake

郭增建先生 (195 7)称 15 5 6年 8 级大地震为关中大地震 ,并绘制了等震线图。 1983年版中国地震目录将其称为华县地震。之后 ,中国地震目录几经修改 ,但对震中位置都没再进行过进一步的研究和修订。 80年代以来 ,几位研究者从不同角度渐次提出这次地震的震中位置不在华县的新见解。本文同意这些见解 ,并通过分析大量史料和对发震构造的研究作进一步论证 ,提出对这次地震震中位置和发震构造的新认识。(1) 15 5 6年 8 级大地震的震中位置不在华县。极震区分布在蒲州 (今永济西黄河东岸 )、朝邑、潼关卫、华阴、华州、解州一带 ,故震中位置宜定在蒲州、潼关卫、华阴、朝邑之间 ,即北纬34°4 4′ ,东经 110°16′ ,震级仍沿用 1995年版中国地震目录修订的 8 级。由于蒲州最重 ,可称为15 5 6年蒲州 8 级大地震。(2 ) 15 5 6年 8 级大地震的发震构造不只是华山山前断裂 ,而是大致沿黄河分布的北北东向右旋走滑断裂带及其南北两端相反方向分布的渭河拉分盆地和运城、临猗一带张性地堑、地垒带 ,由它们共同组合而成的走滑型发震构造带 ,为该次大地震的发震构造。

Based on analysis of the abundant historical earthquake records and recent research results, the newad recognizes for epicenter location and seismogenic structure of 1556 large earthquake are proposed.1. The meizoseismal area of 1556 large earthquake located in the region of the west of Puzhou (Youngzee, east bank of the Huanghe River), Chaoyi, Toungguanwai, Huayin and Giezhou etc. The epicenter is determined in the 34°45'N,110°12'E, between of the Puxian and Tonguan. The earthquake magnitude is 81/4(State Seismological Bureau, 1995) 2. The seismogenic structure of 1556 M 81/4 large earthquake located in the NNE right rateral strik slip fault zone, distribution along the Huanghe River, and its both ends draw basin, south end of Weihe basin and north end of Yunchen basin. The seismogenic structure zone is from their together composition.