燕山地区冀北坳陷元古界下马岭组沥青砂岩岩石学特征和沉积环境*
朱毅秀1,2, 杨程宇1,2, 王欢1,2, 肖劲光1,2

Petrologic characteristics and sedimentary environments of bituminous sandstone in the Proterozoic Xiamaling Formation of Jibei Depression, Yanshan region
Zhu Yi-Xiu1,2, Yang Cheng-Yu1,2, Wang Huan1,2, Xiao Jin-Guang1,2
冀北坳陷下马岭组沥青砂岩样品粒度分析结果图 a—粒度概率累积曲线;b—C-M图