| 摘要: |
| 通过流体包裹体,碳、氧、锶同位素资料分析及盆地模拟,对中扬子北缘京山地区古流体活动期次和流体来源进行研究。结果表明:包裹体均一温度指示京山地区存在4～5幕流体活动,确定地层裂缝中大规模流体活动时间为距今150～60 Ma;方解石脉体中捕获地层水盐度为12％～18％,具高盐度特征;奥陶系和三叠系灰岩围岩与方解石脉体的碳同位素δ13C值相当,方解石脉体沉淀时地层水的氧同位素δ18OSMOW值(5‰～12.5‰)高于海水,成岩流体为源于同层深部地层水;二叠系方解石脉体的δ13C、δ18O值较围岩偏负,锶同位素Sr87/Sr86值(0.707292～0.707735)与同期海水相当,成岩流体源于受有机质影响的本层地层水;中扬子北缘在距今150～60 Ma的构造挤压抬升作用中伴随的流体活动以同层内流动为主,穿层流动和地表水下渗影响微弱,古油气保存条件未遭受严重破坏。 |
| 关键词: 含油气盆地 中扬子地区 方解石脉体 流体包裹体 同位素 油气保存 |
| DOI：10.3969/j.issn.1673-5005.2013.01.004 |
| 分类号::P 597.2; TE 121 |
| 基金项目:国家自然科学重点基金项目(40739904);国家科技重大专项(2011ZX05005-002);国家自然科学基金面上项目(41072093) |
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| Characteristics and pale-fluid activity implications of fluid-inclusion and isotope of calcite veins in Jingshan area |
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YANG Xing-ye1, HE Sheng1, HE Zhi-liang2, WANG Fu-rong1, LI Tian-yi1,2
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(1.Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education, China University of Geosciences, Wuhan 430074, China;2.Research Institute of Petroleum Exploration and Production, SINOPEC, Beijing 100083, China)
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| Abstract: |
| Fluid inclusions, C, O, Sr isotope and basin modeling were carried out to analyze the fluid activity episodes and sources of the fluids in Jingshan area of Northern Mid-Yangtze. The results show that there are four to five fluid activity episodes and large scale fluid flow in formation fracture occurred at 150-60 Ma. Formation water salinity estimated by freezing point of the fluid inclusions captured in calcite vein is mainly distributed in 12％ to 18％, with high salinity characteristics. Ordovician and Triassic formation δ13C values of calcite veins and wall rock limestone are correspond, while the formation water δ18OSMOW values(5 ‰～12.5 ‰) is significantly higher than that of seawater, which illustrates that diagenetic fluids originated from deeply buried wall rock formation water. δ13C, δ18O values of Permian calcite vein are significantly more negative than that of the surrounding rock, whereas strontium isotope Sr87/Sr86values (0.707292～0.707735) are equivalent to that of seawater in the same period, which show that diagenetic fluids originated from Permian formation water affected by organic matter. In the northern margin of Yangtze, fluid activities associated with tectonic compression and uplift at 150-60 Ma are mainly fluid flow within the same layer-based, and mutual-layer flow and influence of surface water infiltration count for little. Petroleum storage conditions did not suffer serious damage. |
| Key words: petroliferous basin Mid-Yangtze area calcite vein fluid-inclusion isotope petroleum preservation |
