河北商庄子可能存在前太古陆壳

详细信息

POSSIBLE EXISTENCE OF THE PRE-ARCHEAN CONTINENTAL CRUST IN SHANGZHUANGZI,QIAN’AN COUNTY,HEBEI

摘要: 某些岩石的铋含量可能具有年龄意义：含量愈低，年龄愈老。迁安商庄子一带出现一个铋的最低区。这里还表现出奇异的地球化学特征：在不大的范围内，既有超基性元素，又有基性、酸性甚至碱性元素的区域地球化学正异常，它们又多为大离子亲石难熔元素。这里可能存在一个前太古地体。此推论也基本获得野外地质资料的佐证。

Abstract: The Bi content in certain rocks may probably have age significance,i.e. the lower the Bicontent,the older the rocks will be.For example,in Shanghuangzi,Qian’an,there is an areawith the lowest Bi content.This area shows a peculiar geochemical features,that is,there areregional geochemical positive anomalies of not only ultrabasic elements but also basic, acid andeven alkaline elements in a not big areal extent.They are mostly large- ion lithophile refracto-ry elements. To there might exist a pre- Archean terrane in the area, This inference is also ev-idenced by field geological data.