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本文通过对长江三角洲地区八个钻孔约二千五百多块古地磁样品的测量,对该地区的第四纪松散沉积物进行了磁性地层划分。其主要认识是:1.布容期沉积物厚度约为60—130m;2.松山期与高斯期的界限位于170—390m;3.该区松散沉积物的底部年龄约为3600—2500ka;4.根据磁性地层对比,该地区不少于三次海浸,第一次海浸为1150—800 ka前;5.窑镇孔底部的玄武岩至少有八次喷发,时代约在5500—3400ka前。
In this paper, the Quaternary loose sediments in the area were magnetically stratified by measuring about 2,500 ancient geomagnetic samples from eight boreholes in the Yangtze River Delta. The main understanding is as follows: 1. The thickness of sediment in cloth-age is about 60-130m; 2. The boundary between Matsuyama period and Gauss period is 170-390m; 3. The bottom age of loose sediment in this area is about 3600-2500ka; 4 According to the comparison of magnetic stratum, there are not less than three sea immersion in the area, with the first sea immersion being 1150-800 ka ago. The basalts at the bottom of the kiln town have at least eight eruptive episodes before about 5500-3400 ka.