鄂尔多斯盆地靖边气田的古地貌定量恢复新方法  

A new method to quantitatively rebuild palaeogeomorphology and its application to Jingbian gasfield Ordos Basin

作　　者：乔博[1] 刘海锋[1] 何鎏[1] 蔡明歌 张芳[1] 袁继明[1] Qiao Bo;Liu Haifeng;He Liu;Cai Mingge;Zhang Fang;Yuan Jiming(Exploration and Development Research Institute,PetroChina Changqing Oilfield Company,Xi'an,Shaanxi 710018,China;Tianjing Branch,CNPC Logging Company Limited,Tianjing 300280,China)

机构地区：[1]中国石油长庆油田分公司勘探开发研究院 [2]中国石油集团测井有限公司天津分公司

出　　处：《天然气勘探与开发》2018年第4期32-37,共6页Natural Gas Exploration and Development

摘　　要：近年来,靖边气田在上、下古生界立体开发过程中,多次在原预测模型的侵蚀沟槽区域发现下奥陶统马五_(1+2)亚段完整,引起人们对原古地貌恢复方法的质疑。为此,综合分析现有古地貌恢复方法的优缺点,基于印模法和残厚法,提出了一种靖边气田的古地貌定量恢复新方法 :选取任意一点作为参考水平面,将该水平面至奥陶系剥蚀面的距离作为古地貌高程值,通过绘制古地貌高程图实现古地貌的定量化表征与侵蚀沟槽预测。结果表明:在靖边气田侵蚀沟槽的重新刻画中,侵蚀沟槽的展布模式由原来的"东西向树枝状沟槽模式"变为"沟槽与潜坑并存模式",且2017年完钻的8口井,有7口井的实钻结果与新方法预测的古地貌相吻合。During 3D development of the Lower and Upper Paleozoic in Jingbian gasfield,complete Lower Ordovician Ma5 1+2 strata have been discovered for many times in an erosion groove area identified on the basis of previous prediction model.And this arouses some doubts about the methods to rebuild existing palaeogeomorphology.In this study,the advantages and disadvantages of existing rebuilding methods were analyzed comprehensively.Then,a new quantitatively rebuilding method suitable for Jingbian gasfield was developed based on other two approaches of both impression and residual thickness.Firstly,one point is selected arbitrarily as a reference level,and the distance between this level and Ordovician denudation surface is taken as the palaeogeomorphologic elevation.And then,quantitative characterization of palaeogeomorphology and prediction of erosion groove are realized by plotting the elevation map.It's indicated that,when this new method is applied to depict the erosion groove in Jingbian gasfield,its distribution mode is changed from"EW dendritic groove"to"groove and shallow pit coexistence".Among 8 wells drilled in 2017,7 wells'drilling results are coincident with the palaeogeomorphology predicted by this new method.

关 键 词：古地貌恢复 靖边气田 下古生界 碳酸盐岩储层 侵蚀沟槽 

分 类 号：P618.13[天文地球—矿床学]