石油与天然气地质 ›› 1997, Vol. 18 ›› Issue (4): 319-325.doi: 10.11743/ogg19970411

• 论文 • 上一篇    下一篇

鄂尔多斯碳酸盐岩去白云石化及其与储集性的关系

覃建雄1, 杨作升2   

  1. 1. 成都理工学院沉积研究所 四川成都 610059;
    2. 青岛海洋大学 山东青岛 266003
  • 收稿日期:1995-02-15 修回日期:1997-01-21 出版日期:1997-12-25 发布日期:2012-01-18

DEDOLOMITIZATION OF CARBONATE ROCKS IN ORDOS AND ITS RELATION TO RESERVOIR PROPERTY

Qin Jianxiong1, Yang Zuosheng2   

  1. 1. Institute of Sedimentology, Chengdu Collegy of Technology, Chengdu, Sichuan;
    2. Qingdao Marine University, Qingdao, Shandong
  • Received:1995-02-15 Revised:1997-01-21 Online:1997-12-25 Published:2012-01-18

PDF (PC)

809

被引次数

19

摘要：

鄂尔多斯下奥陶统碳酸盐岩储层去白云石化主要有下列类型:与不整合面有关的去白云石化主要是大气淡水沿不整合面运移,使其附近的铁白云石发生差异去白云石化,产生大量溶蚀组构和少量去白云石化方解石,以低Sr,Fe,Mn,具低温包裹体等为特征;埋藏环境中去白云石化是与缝合线、石膏结核、埋藏溶蚀孔洞缝和构造裂隙有关的类型,主要与Mg2+的不断消耗、Ca2+含量增加,及有机质热成熟作用和油气的运移聚集有关,以富Mg,Fe,Mn,Sr,低δ18O,δ13C,包裹体均一温度高,可造成大量去白云石化方解石为特征。去白云石化白云岩孔隙度明显比其他类型白云岩和灰岩高,不仅可以提高储层的孔渗性,亦可使非渗透层变为高孔渗层。

关键词: 去白云石化, 碳酸盐岩, 储集性, 鄂尔多斯

Abstract:

The dedolomitization of Lower Ordovician carbonate reservoirs in Ordos Basin could be divided into five types.Dedolonitization related to unconformity is characterized by producing lots of corrosion fabrics, small amounts of dedolomitized calcite with low contents of Sr,Fe,Mn and low homogenization temperature inclusions.Burial environment dedolomitization related to suture lines,gypsum nodules,burial dissolution caves and cracks,structure fissures are mainly resulted from the loss of Mg2+,the increase of Ca2+,the thermal maturation of organic matter and hydrocarbon migration and accumulation.The dedolomitization is charactorized by rich Mg,Fe,Mn,Sr and low δ 18O,δ 13C,high homogenization temperature inclusions,thus forming large amounts of dedolamitized calcite.The porosity of the dedolomitized dolomite is clearly higher than that of other dolomites and limestones.This could not only improve reservoir permeability,but also change nonpermeable beds into permeable ones.