1604年泉州海外大震的发震构造

THE EARTHQUAKE-GENERATING STRUCTURE FOR QUANZHOU BAY MACROSEISM OF 1604

1604年12月29日泉州海外发生了一次强烈地震。震中位于24°54′N、119°24′E,震级8级,震中烈度Ⅺ度,震源深度24—28公里。在震中区附近,城墙倾颓,房屋倒塌,击浪覆舟。地震顷刻,在兴化、泉州、漳州—龙海之间等平原地带,还出现地裂、喷水冒砂的地震形变带,其联线呈NE方向。这次地震,波及福建、浙江、江西及江苏、安徽、上海、湖南、湖北、广西、广东等省市的部分地区,影响最远记录约1000公里。据烈度分布编制的等震线图,极震区长轴为NE方向,与本区NE向构造走向一致。

This paper is an analysis of the earthquake-generating structure for the Quanzhou Bay macroseism of 1604 based on strain accumulation units.It considers that the macroseism occurred in the Quanzhou-Nanri fault block.Situated in that fault block and near the zone of warpage of deep tectonic in the Taiwan Strait and the maximum shear plane position of NEE presure stress,Wuqiu Islet fault is advantageous for the accumulation of strain energy.Bacause of this fault is separated and restrained by the southern boundary of the fault block where several basalt outbursts occurred from the end of Tertiary to early Quaternary,the fault was melted and cemented and a blocked area of fault aceivity was formed.It has accumulated strain energy continuously under the action of NEE pressure stress field.This earthquake was the result that Wuqiu Islet fault displaced dextrally under the action of NEE pressure stress.That seismic rupture expanded from NE to SW end of the fault.The above-mentioned has been confirmed by the occurrance of earthquake and damage of relic buildings.Some problems about pressure stress field are also discussed.