JOPC ›› 2017, Vol. 19 ›› Issue (2): 299-314. doi: 10.7605/gdlxb.2017.02.023

• LITHOFACIES PALAEOGEOGRAPHY AND SEDIMENTOLOGY • Previous Articles     Next Articles

Sedimentary characteristics and petroleum geologic significance of deep-water gravity flow of the Triassic Yanchang Formation in southern Ordos Basin

Sun Ningliang1, Zhong Jianhua1, Wang Shubao2, Liu Shaoguang3, Ni Liangtian1, Qu Junli4, Hao Bing1, Liu Chuang1   

  1. 1 School of Geosciences,China University of Petroleum(East China),Qingdao 266580,Shandong;
    2 Yanchang Oil Field Co., Ltd., Xi'an 710018,Shaanxi;
    3 Exploration & Development Technology Research Center of Yanchang Oil Field Co., Ltd., Yan'an 716000, Shaanxi;
    4 Strategic Research Center of Oil and Gas Resources,Ministry of Land & Resources,Beijing 100034;
  • Received:2015-10-19 Revised:2016-02-01 Online:2017-04-01 Published:2017-04-01
  • About author:About the first author Sun Ningliang,born in 1987,is a doctoral candidate of China University of Petroleum(East China). Now he is mainly engaged in deep-water gravity flow and unconventional petroleum geology. E-mail: 296182073@qq.com.
  • Supported by:
    Co-funded by the National Natural Science Foundation of China(No.41172093),the Fundamental Research Funds for the Central Universities(No.15CX06002A)and Graduate Innovation Project of China University of Petroleum(East China)(No.YCX2015004)

鄂尔多斯盆地南部三叠系延长组深水重力流沉积特征及其石油地质意义*

孙宁亮1, 钟建华1, 王书宝2, 刘绍光3, 倪良田1, 曲俊利4, 郝兵1, 刘闯1   

  1. 1 中国石油大学(华东)地球科学与技术学院,山东青岛 266580。
    2 延长油田股份有限公司,陕西西安 710018。
    3延长油田股份有限公司勘探开发技术研究中心,陕西延安 716000。
    4国土资源部油气资源战略研究中心,北京 100034
  • 作者简介:孙宁亮,男,1987年生,中国石油大学(华东)地球科学与技术学院博士研究生,主要从事重力流沉积及非常规油气地质研究。E-mail: 296182073@qq.com。
  • 基金资助:
    *国家自然科学基金项目(编号:41172093),中央高校基本科研业务费专项资金(编号:15CX06002A)和中国石油大学(华东)研究生创新工程(编号:YCX2015004)联合资助

Abstract: Through the observation of abundant cores, analysis of drilling and logging data,and outcrop observation,the sedimentary characteristics,triggering mechanisms,sedimentary process and pattern of deep-water gravity flow were analyzed in detail in the Chang 6-7 intervals of the Triassic Yanchang Formation,southern Ordos Basin. The results show that there are five types of gravity flow sediments,which are slipped mass,slump deposits,sandy debris flow deposits,turbidity deposits and muddy debris flow deposits. There are five vertical combination styles of gravity flow deposits in the study area. The sedimentary process of gravity flow can be divided into five stages,which are delta front sedimentary stage,slide stage,slump deformation stage,sandy and muddy debris flow stage and turbidity flow stage. Slide and slump sand bodies are formed in shapes of isolated lens;sandy debris flow sand bodies are formed in fan channel;and turbidity sand body are formed as sheet sand,mainly distributing in the front or sides of the fan channel. Sand bodies of deep-water gravity flow are vertically superposed in large thickness,which could form large scale reservoirs and extremely extends the exploration of deep lake sedimentary facies. In the study area,sand bodies of sandy debris flow in Chang 6-7 intervals are worth of great concern for their preferable physical properties and hydrocarbon potential.

Key words: deep-water gravity flow, sedimentary characteristics, petroleum geology, Yanchang Formation, Triassic, Ordos Basin

摘要: 通过大量岩心观察、钻测井资料分析及野外露头观察,对鄂尔多斯盆地南部延长组长6—长7深水重力流沉积特征、触发机制、沉积过程、沉积模式及石油地质意义进行了系统分析。研究结果表明:研究区共存在滑动岩体、滑塌沉积、砂质碎屑流沉积、浊流沉积及泥质碎屑流沉积5种类型的重力流沉积物,各类型的沉积物特征明显。不同类型重力流沉积物垂向组合可分为5类,研究区重力流的形成过程可分为5个阶段:三角洲前缘沉积阶段、滑动阶段、滑塌变形阶段、砂质碎屑流及泥质碎屑流形成阶段以及浊流形成阶段。滑动、滑塌砂体多呈孤立透镜体状,砂质碎屑流砂体多以扇沟道的形式展现出来,浊流砂体多分布在扇沟道的前端或侧翼,呈席状砂展布。深水重力流砂体垂向叠置厚度大,可形成规模大的油藏,大大扩展了深湖的勘探范围。研究区长6、长7油层组砂质碎屑流砂体储集层物性较好,含油性好,是重点勘探层位。

关键词: 深水重力流, 沉积特征, 石油地质, 延长组, 三叠系, 鄂尔多斯盆地