地球学报Issue(1):49-58,10.DOI:10.3975/cagsb.2014.01.07
大巴山燕山期陆内造山地质流体活动特征
Geofluids Features in the Daba Mountain during Yanshanian Intracontinental Orogenic Movement
摘要
Abstract
During the Yanshanian intracontinental orogenic movement, the Daba Mountain area was strongly deformed and four tectonic deformation belts were formed from northeast to southwest, i.e., thrust-nappe belt, foreland basement detachment belt, foreland decollement belt and foreland depression belt. Accompanying the strong tectonic movement, large scale fluid flow occurred and lots of fault planes were filled with calcite veins crystallized from geological fluids. Across the tectonic deformation belts, samples of calcite were collected from the fault planes and their wall rocks for the analysis of trace elements and rare earth elements (REE), so as to trace the fluid origin, restore the environment of crystallization and reveal the relationship between the tectonic deformation belts and the fluid flow. Trace elements and REE features of all samples show that calcites were of hydrothermal origin and the fluids that crystallized calcites were mainly derived from wall rocks with the mixture of some other fluids. From thrust-nappe belt to foreland depression belt, the distribution of trace elements As, Co, Ni, Sc, Li and Ge regularly changed in accordance with different tectonic deformation belts, suggesting the variation from thrust-nappe belt to foreland depression belt; the fluid environment changed from low to high oxidation, pH values changed from low to high, and the organic components in fluids also correspondingly increased. The tectonic deformation belts, especially the important boundary faults, controlled the environment of fluid flow and the distribution of some trace elements in the Daba Mountain. The information obtained by the authors is important for tectonic research and oil and gas exploration in Daba Mountain area.关键词
大巴山/构造变形带/流体/方解石/围岩/微量元素/稀土元素Key words
Daba Mountain/tectonic deformation belts/fluid/wall rock/trace element/REE分类
天文与地球科学引用本文复制引用
黄始琪,董树文,黄德志,施炜,王显莹,李国明,张进富..大巴山燕山期陆内造山地质流体活动特征[J].地球学报,2014,(1):49-58,10.基金项目
本文由中石化海相前瞻性研究专项“大巴山前陆构造演化与油气远景研究”(编号:YPH08023)和国家专项“深部探测技术与实验研究”(编号:SinoProbe-08-01)联合资助。 (编号:YPH08023)