莺歌海盆地东方1—1气田天然气来源与运聚模式  

Origin and Accumulation Model of Natural Gases in the Dongfang 1-1 Gas Field of the Yinggehai Basin

作　　者：赵必强[1] 肖贤明[1] 胡忠良[1] 黄保家[2] 

机构地区：[1]中国科学院广州地球化学研究所有机地球化学国家重点实验室,广州510640 [2]中国海洋石油有限公司湛江分公司技术部,广东湛江524057

出　　处：《沉积学报》2005年第1期156-161,共6页Acta Sedimentologica Sinica

基　　金：国家自然科学基金资助项目(批准号: 40072043);中国科学院广州地球化学研究所前沿领域性项目(GIGCX-04-08).

摘　　要：莺歌海盆地东方 1—1气田以其埋藏浅、天然气成份变化大、气藏位于底辟构造带等特征一直是研究的热点。长期以来对其气源、充注历史等问题存在不少疑问。该研究应用生烃动力学与碳同位素动力学方法通过对典型烃源岩的研究,建立起了烃源岩在地质条件下的生气模式与碳同位素分馏模式。结合天然气地质地球化学特征,研究认为:东方 1—1气田烃类气体主要来源于梅山组烃源岩,非烃气体来源于三亚组或更深部含钙地层;天然气藏形成相当晚,与底辟作用有关,烃类气体主要充注时间在 1. 3Ma以后,CO2气体主要充注时间在 0. 1Ma左右;天然气成份的非均一性主要受控于底辟断裂活动所控制的幕式充注。The Dongfong 1-1 Gas Field of the Yinggehai Basin has great attractiveness because its characteristics of a shallow burial depth, wide variations of gas composition and occurrence in the diapir fault belt. There have been still problems on gas source and gas-filling model for a long period. In this paper, the method of hydrocarbon generation kinetics and carbon isotopic fraction kinetics was applied to some typical source rocks from this basin, and a geological model of gas generation and methane carbon isotopic fraction was suggested. With the combination of the geological and geochemical background of the Dongfong 1-1 Gas Filed, it was believed that the hydrocarbon gases were mainly from the coal measure source rocks in the Meishan Formation, but non-hydrocarbon gas the calcareous shale in the Shanya Formation. The gas pool is quite young, and is related to the diapirism. The hydrocarbon gas was charged after t 1.3 Ma, and CO 2 gas at about 0.1 Ma. The wide variation compositions of the natural gas were controlled by episode charges of gases controlled by diapir fault activities.

关 键 词：莺歌海盆地 烃源岩 碳同位素 地质地球化学特征 非烃气体 断裂活动 天然气藏 气田 烃类气体 生烃动力学 

分 类 号：P618[天文地球—矿床学] TE122[天文地球—地质学]