三塘湖盆地石炭系火山岩中断层封闭机理研究  

Fault Sealing Mechanism of Carboniferous Volcanic Rocks in Santanghu Basin

作　　者：柳成志[1] 于海山[1] 雷海艳[1] 刘倩[1] 刘蓓蓓[1] 

机构地区：[1]东北石油大学地球科学学院,大庆163318

出　　处：《科学技术与工程》2011年第23期5517-5523,共7页Science Technology and Engineering

基　　金：中国石油天然气股份有限公司专题项目(2008B-0101)资助

摘　　要：三塘湖盆地石炭系火山岩中几乎所有的油气藏都聚集在断层圈闭中,体现了断层对火山岩油气成藏具有很强的封闭能力。研究认为三塘湖盆地石炭系火山岩中断层具有垂向和侧向两种封闭性。垂向封闭性主要取决于断裂中充填物的排替压力,而排替压力大小主要与充填物的成分和充填程度相关。在火山岩中断裂充填物无非是火山岩自身破碎的岩屑和泥岩两种,泥岩充填在一定条件下具有很好的封闭性,而单纯的火山岩自身碎屑充填一般不具封闭性。但由于石炭系火山岩受到烃碱流体作用,碱交代所形成的"上硅下碱"的结果使SiO2在局部层段将火山岩自身破碎的岩屑胶结起来,形成垂向封闭。因此,火山岩中断层垂向封闭存在泥质充填和SiO2胶结2种机理。在断层两盘对应火山岩储层内,油气通常呈现"此消彼长"的现象,这是断层侧向封闭性的体现。从引起差异渗透的因素来看,火山岩中侧向封闭存在岩性对接、泥岩涂抹和胶结封闭3种机理。每种机理在不同的地质情况下对火山岩中油气聚集发挥作用。Carboniferous volcanic rocks in the oil and gas reservoirs are almost all gathered in fault traps in San- tanghu basin, reflects the faults of the volcanic gas reservoir has a strong sealing ability. Study suggests santanghu basin and carboniferous volcanic rocks in the fault basin with two vertical and lateral seal. Vertical sealing depends primarily level. In on the fracture filling line for pressure, but the main row size for pressure and filling ingredients and filling volcanic rocks of volcanic rock fracture filling is nothing more than their own broken rock debris and mud, mudstone filling under certain conditions with good sealing, the simple volcanic debris filling their general non- closed. However, since the carboniferous volcanic rocks in effect by the hydrocarbon base fluid, explain the forma- tion of alkali＂ on the silicon under the base＂ of the result will SiO2 layers in the local volcanic debris cemented itself broken up, the formation of vertical closure. Therefore, the volcanic rocks in the clay filled fault exists and vertical sealing cement two kinds of mechanism of Si02. In fault corresponding volcanic reservoir, oil and gas are usually present＂ the shift＂ phenomenon, this is a manifestation of lateral seal. Looking from causes the difference infiltration factor, volcanic rock in the presence of lateral seal butt, shale smear and cementation closed three kinds of mechanism. Each mechanism under different geological conditions in the oil and gas accumulation on the role of volcanic rock.

关 键 词：三塘湖盆地 火山岩 断层 封闭机理 烃碱流体 

分 类 号：P618.130.22[天文地球—矿床学]