黔东震旦系-下寒武统黑色岩系稀土元素地球化学特征  

REE Geochemical Characteristics of the Ediacaran—Lower Cambrian Black Rock Series in Eastern Guizhou

作　　者：杨兴莲[1] 朱茂炎[2] 赵元龙[1] 张俊明[2] 郭庆军[3] 皮道会[3] 

机构地区：[1]贵州大学资源与环境工程学院,贵州贵阳550003 [2]中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室,江苏南京210008 [3]中国科学院地球化学研究所环境地球化学国家重点实验室,贵州贵阳550002

出　　处：《地质论评》2008年第1期3-15,共13页Geological Review

基　　金：国家自然科学基金资助项目(编号40162002);黔科合J字[2007]2151号;973项目(编号2006CB806401);中国科学院知识创新工程重要方向项目(KZCX3-SW-141);贵州大学博士启动基金项目的成果。

摘　　要：通过对黔东丹寨南皋剖面和三都渣拉沟剖面的稀土元素分析发现:两条剖面的梅树村期与筇竹寺期分界处大量稀土元素明显富集,黑色页岩中存在明显的Ce负异常和Eu、Y正异常,表明为缺氧和热水沉积的产物。这套黑色岩系总体沉积于缺氧和具热水注入的环境中,但发生缺氧和热水注入的时间和强度在不同地方会有不同的表现。Analyses of REEs from the Ediacaran-Cambrian transition interval black rock series on Nangao section and Zhalagou section, eastern Guizhou, South China, characterized by：（1） lots of REEs enriched at the boundary between the Meishucunian and Qiongzhusian; （2） a distinct negative Ce anomaly and a positive Eu anomaly, indicate anoxic conditions with hydrothermal inputs. However, oxygen-deficient environment and hydrothermal inputs varied between the sections. The black shale of the Niutitang Formation in Danzhai was deposited in an oxygen-deficient environment gradually transforming to an oxic environment in the shallow shelf area, with occasional upwelling and hydrothermal fluid input. The black chert of the underlying Laobao Formation formed in an oxic environment between the shelf and slope. In contrast, the silicastone of the Laobao Formation in Sandu formed in an anoxic environment in deeper water with frequent hydrothermal activity, as in western Hunan and the Tarim Basin.

关 键 词：黑色岩系 前寒武纪 寒武纪转换时期 稀土元素 黔东 

分 类 号：P595[天文地球—地球化学]