浙西、冀东寒武-奥陶系灰岩地层的热发光特征

本文试图以浙西江山碓边大豆山和冀东卢龙武山两个地表剖面为例,应用热发光测量数据,分析并探讨对灰岩地层划分和对比的可能性。其目的是为了建立寒武系与奥陶系的界线特点和对比特征。经对2000多个热发光测量参数的处理,初步归结出以下几个问题。

THERMOLUMINESCENCE OF THE CAMBRIAN AND ORDOVICIAN LIMESTONES FROM EASTERN HEBEI AND WESTERN ZHEJIANG, CHINA

This paper deals with the possibility of division and correlation of limestone strata by means of thermo uminescence technique. The rock samples were colleted from a profile of Dadoushan,Jiangshan County in. Western Zhejiang and from another one of Wushan,Lulong County in Eastern Hebei. The purposes are to establish the boundary between Cambrian and Ordovician,and to find their correlative characteristics on the basis of more than 2000 thermoluminescence data.The thermoluminescence intensities of both ATL and NTL of the samples from the two profiles exhibit that the older rocks have stronger thermoluminescence,and in Jiangshan profile,this tendency is more remarkable. However,there are special thermoluminescence features at the boundary between the Lower Ordovician and the Upper Cambrian,which are useful for the horizon division.Generally,the division and correlation of strata by thermoluminescence technique are feasible within a tectonic unit or within a close distance. However,for the division and correlation of the Lower Ordovician and the Upper,Middle Cambrian strata from the Southern and Northern profiles (Jiangshan and Lulong),we don’t have enough data,and further works must be done in the future. Therefore,the division and correlation of the younger atrata by thermoluminescence technique are more efficient than those of the older ones as shown in this work.This paper suggests that the application of thermoluminescence technique for dividing and correlating strata is more or less fruitful. There are many factors which affect this technique,such as sedimentary environment,nature of sedimentary sources,tectonic condition,paleoclimate,chemical composition of the rocks and so on. Therefore,to interpret the mechanism of strata division and correlation using thermoluminescence technique is more complicated than intuitively using this technique. Of course,it is necessary to do more detailed work for understanding this mechanism.