北拉萨地体白垩纪郎山组岩石薄片显微图像数据集  

A photomicrograph dataset of mid-Cretaceous rocks from Langshan Formation in northern Lhasa Terrane,Tibet

作　　者：许艺炜 胡修棉[1] 孙高远 Xu Yiwei;Hu Xiumian;Sun Gaoyuan(School of Earth Sciences and Engineering,Nanjing University,Nanjing 210023,P.R.China;College of Oceanography,Hohai University,Nanjing 210098,P.R.China)

机构地区：[1]南京大学地球科学与工程学院,南京210023 [2]河海大学海洋学院,南京210098

出　　处：《中国科学数据（中英文网络版）》2020年第3期65-72,共8页China Scientific Data

基　　金：国家杰出青年基金项目(41525007)。

摘　　要：沉积微相研究是碳酸盐岩沉积环境研究的基础,然而高度概括的微相划分容易丢失沉积环境的渐变演化过程。一条剖面所有岩石薄片的显微图像可以很好地补充不同微相之间的连续变化过程。本文以西藏中部郎山组碳酸盐岩为对象,对区域上3条平行剖面、559个薄片进行显微拍照,并记录了样品的采集位置、地层时代、岩石名称、岩石特征等信息。本显微照片数据集显示郎山组岩性主要为灰岩和白云岩,其中灰岩以粒泥灰岩、泥晶灰岩和漂砾灰岩为主。本数据集可广泛应用于北拉萨地体白垩纪地层相关的基础地质学研究,也可应用于相关油气勘察等实践生产。其中,薄片中典型的沉积特征,还可应用于白垩纪碳酸盐相模式研究、教学与科普。Microfacies analysis constitutes the basis for studying carbonate sedimentary environments. The scholarly tendency to categorize microfacies into distinct types, however, risks ignoring the continuity and congruity between different environments. To address this predicament, we studied the carbonate strata from Langshan Formation in central Tibet. We collected polarized photomicrographs of 559 thin sections from three stratigraphic sections of the Langshan Formation, and described the location, stratigraphic age, lithology and petrography of these thin sections. The results show the lithology of the Langshan Formation including limestone and dolostone, where the wackestone, mudstone and floatstone are the dominants in the limestone. This photomicrograph dataset can be used to support basic geological research, oil exploration, carbonate facies modelling, teaching and general science popularization.

关 键 词：拉萨地体 白垩纪中期 郎山组 偏光显微图像 

分 类 号：P618.13[天文地球—矿床学]