鄂尔多斯盆地合水地区延长组长6段砂体结构特征及成因分析  

Sandbody structural characteristics of Chang 6 Member of Yanchang Formation and its origin in Heshui area,Ordos Basin

作　　者：杨孝 李廷艳[2,3] 尤源[2,3] 郝炳英[2,3] 冯胜斌[2,3] 毛振华[2,3] YANG Xiao;LI Ting-yan;YOU Yuan;HAO Bing-ying;FENG Sheng-bin;MAO Zhen-hua(Department of Reservoir Evaluation, Changqing Oilfield Company, PetroChina, Xian 710018, China;Exploration and Development Research Institute of Changqing Oilfield Company, PetroChina, Xian 710018, China;National Engineering Laboratory for Exploration and Development of Low-Permeability Oil & Gas Fields, Xi'an 710018, China)

机构地区：[1]中国石油长庆油田分公司油藏评价处,西安710018 [2]中国石油长庆油田分公司勘探开发研究院,西安710018 [3]低渗透油气田勘探开发国家工程实验室,西安710018

出　　处：《世界地质》2016年第3期789-800,共12页World Geology

基　　金：国家重点基础研究发展计划(973计划)(2014CB239003);国家自然科学基金重大项目(41390451);国家科技重大专项(2016ZX05046005)联合资助

摘　　要：通过岩芯及露头观察对鄂尔多斯盆地合水地区延长组长6段砂体沉积类型的识别、依据沉积组合对砂体结构进行分类、并结合测井响应特征刻画了砂体结构平面分布,综合分析了砂体结构平面差异的成因。结果显示,合水地区长6段主要为深水重力流沉积,可识别出砂质碎屑流和浊流两种不同的重力流沉积类型。两种重力流沉积砂体在纵向上复合叠置形成广泛分布的厚砂体,因组合关系及含油性不同,可分为3种砂体结构类型:多期砂质碎屑流叠加型、砂质碎屑流与浊流复合叠加型及多期浊流叠加型。砂体结构平面分布差异受湖盆底形、物源及供屑量和流体重复改造等因素影响,不同结构砂体平面上具有垂直物源轴线呈带状展布特征,在合水地区东北部和中部形成较为有利的砂体结构类型。The deposition types of Chang 6 M e m b e r of the Yanchang Formation in Heshui area of Ordos B a sin, were firstly identified by core and outcrop observations, and then the sandbody structures were classified according to the combination of deposition types. Furthermore, the distributions of sandbody structure were revealed by logging responses, and the reasons for the plane differences of sandbody structures were synthetically analyzed.The results show that the main deposition type of Chang 6 M e m b e r in Heshui area was deep-water gravity flow deposition,which can be further divided into sandy debris flow deposition and turbidity current deposition. These two types of gravity flow depositions superimposed vertically, leading to widespread and thick sandbodies, which can be classified as superimposition of multi-stage sandy debris flow deposition, superimposition of sandy debris flow deposition and turbidity current deposition, and superimposition of multi-stage turbidity current deposition according to the differences in storage ability and oil enrichment. The distributive difference of sandbody structure effected by the bottom shape of lake basin, provenance, amount of debris and transformation of flow. Different types of sandbody have the belt distribution characteristics of vertical provenance axis, and the favorable sandbodies are in the northeastern and central parts of the Heshui area.

关 键 词：鄂尔多斯盆地 合水地区 延长组 长6段 砂体结构 重力流沉积 

分 类 号：P618.130.21[天文地球—矿床学]