油气沿不同时期断裂穿过泥岩盖层渗滤散失的地质条件及其识别方法

发布时间：2018-04-16 21:29

本文选题：油气 + 泥岩盖层　；参考：《现代地质》2017年02期

【摘要】：为了研究含油气盆地断裂发育区油气分布规律,在确定油气沿活动期和静止期断裂穿过泥岩盖层发生渗滤散失机理的基础上,针对油气沿活动期和静止期断裂穿过泥岩盖层渗滤散失的地质条件及识别方法进行了研究。研究结果表明:油气沿活动期断裂穿过泥岩盖层渗滤散失所需的地质条件是活动期断裂在盖层内上下连接分布,作为油气穿过泥岩盖层的输导通道;油气沿静止期断裂穿过泥岩盖层渗滤散失所需的地质条件是下伏储层油气剩余压力大于断层岩排替压力。通过比较泥岩盖层断接厚度与油气沿活动期断裂穿过泥岩盖层渗滤散失所需最小断接厚度的相对大小和下伏储层剩余压力与断层岩排替压力的相对大小,分别建立了油气是否沿活动期断裂和静止期断裂穿过泥岩盖层渗滤散失的识别方法,并将其应用于渤海湾盆地南堡凹陷南堡5号构造天然气能否通过活动期和静止期NP5-2断裂穿过东二段泥岩盖层渗滤散失的识别。结果表明:在断裂活动期,仅在L_2和L_8测线处天然气可以沿着NP5-2断裂穿过东二段泥岩盖层渗滤散失,其余测线处(L_1、L_3、L_4、L_5、L_6、L_7、L_9)则不能;但是在断裂静止期,天然气不能沿NP5-2断裂穿过东二段泥岩盖层渗滤散失,与目前南堡5号构造东二段泥岩盖层之下已发现的天然气分布相吻合,表明这2种方法分别用于识别油气是否通过静止期断裂和活动期断裂穿过泥岩盖层渗滤散失是可行的。
[Abstract]:In order to study the distribution of oil and gas in fault development area of oil-bearing basin, on the basis of determining the mechanism of percolation loss of oil and gas through mudstone caprock during active and static period,The geological conditions and identification methods of percolation loss of oil and gas through mudstone caprock along active and static faults are studied.The results show that the geological condition of percolation loss of oil and gas through mudstone caprock along active fault is that the active fault connects up and down in the caprock and acts as the passage of oil and gas passing through mudstone caprock.The geological conditions for percolation loss of oil and gas through mudstone caprock along the static fault are that the residual pressure of oil and gas in the underlying reservoir is greater than the displacement pressure of fault rock.By comparing the relative thickness of mudstone caprock fracture with the minimum fracture thickness required for seepage loss of oil and gas through mudstone caprock along active fault stage, the relative magnitude of residual pressure of underlying reservoir and displacement pressure of fault rock are compared.The methods of identifying whether oil and gas percolate through mudstone caprock along active fault and static fault are established respectively.And it is applied to identify whether the natural gas of Nanbao No. 5 structure in Nanpu depression of Bohai Bay basin can pass through the mudstone caprock of the eastern second member of the Bohai Bay basin through the active and static NP5-2 faults.The results show that during the active period of the fault, natural gas can pass along the NP5-2 fault along the NP5-2 fault through the mudstone caprock of the second member of the eastern section for leachate loss, while at the rest of the survey lines, it is not possible only at the stage of the fault activity.Natural gas can not pass through the mudstone caprock of the eastern second member along the NP5-2 fault, which is consistent with the distribution of natural gas found under the mudstone caprock of the eastern second member of Nanpu No. 5 structure at present.The results show that it is feasible to use these two methods to identify the seepage loss of oil and gas through mudstone caprock by static fault and active fault respectively.
【作者单位】：东北石油大学地球科学学院;大庆油田有限责任公司第一采油厂;
【基金】：国家自然科学基金项目(41372154,41372153) 东北石油大学研究生创新科研项目“油气成藏期断层侧向封闭能力综合定量评价”(YHSCX2015-002NEPU)
【分类号】：P618.13

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