地质论评2009，Vol.55Issue(6)：795-803,9.
贵州罗甸晚二叠世辉绿岩及其区域构造意义
Late Permian Diabase in Luodian, Southeastern Guizhou,and Its Tectonic Significances
韩伟 1罗金海 1樊俊雷 2曹远志 3张静艺4
作者信息
- 1. 大陆动力学国家重点实验室(西北大学)西北大学地质学系,西安,710069
- 2. 陕西省煤田地质局勘察研究院,西安,710005
- 3. 中石化西北油田分公司,乌鲁木齐,830011
- 4. 冀东油田勘探开发研究院,河北唐山,063004
- 折叠
摘要
Abstract
The diabase exposed in Luodian area,southeastern Guizhou Province,belongs to tholeiite series.The major elements of the diabase are characterized by high TiO_2 (2.36%～2.57%),high CaO(9.40%～10.31%),low MgO(5.65%～6.93%),low alkali and Na_2O＞K_2O;the diabase have a higher content of ΣREE(164.9×10~(-6)～187.3×10~(-6)) with a remarkable fractionation between LREE and HREE reflecting the enrichment of LREE and the depletion of HREE.Meanwhile,the testing result pronounces a significant positive Eu anomaly and the chondrite-normalized distribution curve is right inclined.The U-Pb dating result from zircons in the diabase samples yields a concordant lower intersection age (tested by LA-ICP-MS),255.0±0.62Ma, which may represents the rock mass crystallization time.Combining with the regional geology analysis, we believe that the diabase of Luodian area possibly originates from the partial melting of the peridotite approaches in the primitive mantle,and the magmas probably suffer from the contamination of crust materials during the rapid rising process.The Luodian diabase has a similar geochemistry characteristic with the Emeishan basalt,and its formation age is nearly at the same time with the main eruption period of Emeishan basalt.The comprehensive analysis proves that the late Permian diabase from the southeastern Guizhou Province is the product of polymorphism magmatic activities of the Emeishan basalt,and the Luodian-Wangmo area of the southeastern Guizhou Province lies in the eastern boundary zone of the Emeishan basaltic magmatism.关键词
辉绿岩/地球化学特征/构造环境/罗甸地区Key words
diabase/ geochemical characteristics/ tectonic setting/ Luodian/ Guizhou分类
天文与地球科学引用本文复制引用
韩伟,罗金海,樊俊雷,曹远志,张静艺..贵州罗甸晚二叠世辉绿岩及其区域构造意义[J].地质论评,2009,55(6):795-803,9.
