高级检索

    鄂尔多斯盆地合水—塔尔湾地区长6~长10油层组沉积相研究

    Sedimentary facies of the Chang6-Chang10 intervals in Heshui-Ta’erwan area, Ordos Basin

    • 摘要: 提要:沉积砂体成因类型影响了鄂尔多斯盆地合水—塔尔湾地区油气资源勘探,本文通过野外露头和岩心沉积特征分析,结合测井、录井资料,在合水—塔尔湾地区延长组长6~长10油层组识别出曲流河三角洲、辫状河三角洲、湖泊和滑塌扇等沉积类型,详细分析了不同沉积类型的亚微相特征,指出重力流沉积体系主要为经典浊积岩和砂质碎屑流。合水—塔尔湾地区长6~长10主要物源来自于西南方向,为辫状河三角洲沉积体系,次要物源来自于东北,发育曲流河三角洲前缘,中部发育湖泊沉积以及滑塌扇。研究区从长10到长6经历了湖侵到湖退的过程,西南物源持续退积,由辫状河三角洲平原逐渐演化为前缘,并在前端沉积深水滑塌扇,东南物源在长6及长8发育曲流河三角洲前缘。研究表明,合水—塔尔湾地区长7湖相泥岩生烃,长8和长6三角洲前缘水道、长7和长6滑塌扇砂体构成有利勘探目标。

       

      Abstract: Abstract:Genetic types of sedimentary sand bodies affect oil and gas exploration in the Heshui-Ta’erwan area of Ordos Basin. Based on outcrop and core characteristics analysis, combined with well logging data, the authors recognized various types of sedimentary facies of the Chang6-Chang10 intervals in the study area, i.e., normal delta, braided delta, lacustrine system and slump fan, and made a detailed discussion on the subfacies. The turbidite and sandy debris flow sediments are the major gravity flow deposition systems. The primary braided delta deposits came from the southwest, the minor normal delta deposits came from the northeast, and the slump fan developed in the middle. The study area experienced transgression and regression during the deposition of Chang6-Chang10 intervals. The southwestern braided delta kept retrograding and slump fan developed in the front in deep water ultimately. The northeastern normal delta deposits are found mainly in the Chang6 and Chang8 intervals. It is revealed that source rocks developed in the Chang7 interval, and both underwater distributary channels in the Chang6 and Chang8 interval and gravity flow sediments in the Chang7 and Chang6 interval are potential exploration targets.

       

    /

    返回文章
    返回