泉州平原—海湾地区现今地壳活动性

THE ACTIVITIFS OF THE EARTH CRUST DURING THE MODERN TIMES IN THE QUANZHOU GULF-PLAIN AREA

本文在分析地质、地貌资料的基础上,根据史志、考古、测量、地震等资料,就晋江下游的泉州平原——海湾地区现今地壳活动性作一初步探讨。一、构造格架本区岩层,主要分布着燕山期花岗岩和上覆薄层第四纪沉积物。地质构造较为复杂,以断裂为主要特征,有NE向的长乐——诏安断裂带和NW向晋江断裂带通过本区(图1)。长乐——诏安断裂带在本区由四条断裂组成,自内陆向海为莲塘——东田断裂、惠安岭——罗裳山断裂、小岞——金井断裂和近岸篠蚨狭?其走向大多为NE40°,倾向SE或NW,倾角50°左右。晋江NW向断裂带在区内分布有杏田——张坂断裂、双阳——洛阳江断裂、清源山南侧断裂和亭店——下辇断裂,其走向大多在300°左右,倾向不一,倾角较陡。

Baaed on the geological and morphological analyses,historical data,archaeology and topographic surveys,the activities of the earth crust during the modern times in the Quanzhou Gulf-Plain are discussed.It is recognized that one of the dominant factors causing the gradual emergence of the plain was the fall of the sea level in a wide in recent 2000 years.In addition,the emergence was alto constrained greatly by the tectonic movements simultaneously.Since the end of the late-Pleistocene or the early-Holocene periods.NW-fault subsidence has developed in the area,governing the physical features of the Gulf-Plain and the Holocene deposits,being expresaed in their different developmental courses.A lot of modern data indicate that the diastrophism of the earth crust is rather brisk and active.The earth crust move ment is tending to be strengthened on the crossed areas of the two-set faults differential movements of the fault massif are evident in this dtstrict,having the same fieatures of diastrophism since the late-Pleistocene period.The area is now still in a tendency of subsidence.