鄂尔多斯盆地奥陶系马家沟组层序地层特征及控藏作用  

Sequence stratigraphic features and their control over hydrocarbon accumulation of Ordovician Majiagou formation in the Ordos basin

作　　者：王龙[1] 梅朝佳 李屹尧 赵静 

机构地区：[1]中国地质大学(北京)地球科学与资源学院,北京100083 [2]中国石油集团渤海钻探工程有限公司测井分公司,天津300457

出　　处：《东北石油大学学报》2018年第3期26-36,112,共12页Journal of Northeast Petroleum University

基　　金：国家科技重大专项(2011ZX05004-002);国家自然科学基金项目(41472090;40472065)

摘　　要：为揭示鄂尔多斯盆地奥陶系马家沟组层序地层发育特征及其对油气成藏的影响,结合钻井和野外露头等资料,采用曲线频谱趋势属性分析技术,根据层序地层四分模式划分奥陶系马家沟组层序地层,分析层序地层格架下的油气藏分布和发育规律。结果表明:马家沟组可以分为4个三级层序,SQ1由马一段至马三段构成,SQ2由马四段和马五_(10)至马五_6亚段构成,SQ3由马五_5至五_1亚段构成,SQ4由马六段构成,只在局部残存;每个层序内部的地层叠加形式有3种,分别为海侵、正常海退及强迫型海退成因的沉积;烃源岩和储集层的发育明显受层序格架控制,主要形成于海退阶段,层序SQ4或SQ3顶部的区域不整合面长期遭受风化剥蚀,控制风化壳型储集层的发育。该结果为鄂尔多斯盆地天然气藏的勘探提供指导。In order to reveal the characteristics of the sequence stratigraphy and their impact on hydrocarbon accumulation of Ordovician Majiagou formation in the Ordos basin,the reservoir development and distribution pattern of Ordovician Majiagou formation is established systematically under the sequence stratigraphic framework in this basin,which is based on the Helland sequence stratigraphic model,using the spectral curve attribute analysis together with drilling and field outcrop data.The results are as follows:The Majiagou formation can be divided into four third-order sequences,among which,SQ1 is composed of Ma1 member to Ma3 member,SQ2 is composed of Ma4 member to Ma56 member,SQ3 is composed of Ma55 to Ma51 member,and SQ4 is composed of Ma6 member.There are three types of stratigraphic superposition within each sequence,which are "transgression", " normal regression" and "forced regression" deposits according to sedimentary genesis.The development and distribution of source rocks and reservoirs are obviously controlled by sequence framework.They are mainly formed inthe forced regression stage.While the regional unconformity,subjected to weathering and denudation for a long time,controls the distribution of residuum reservoirs at the top of sequence SQ4 or SQ3.These results provide some guidance for natural gas exploration in Ordos basin.

关 键 词：鄂尔多斯盆地 马家沟组 层序地层 频谱趋势属性分析 储集层 烃源岩 

分 类 号：P618.13[天文地球—矿床学] TE122.1[天文地球—地质学]