石油学报 ›› 2011, Vol. 32 ›› Issue (3): 459-465.DOI: 10.7623/syxb201103012

• 地质勘探 • 上一篇    下一篇

碳酸盐岩储层孔隙结构评价方法——以土库曼斯坦阿姆河右岸气田为例

郭振华 1  李光辉 1  吴  蕾 2  李序仁 2  韩桂芹 1  姜英辉 1   

  1. 1中国石油长城钻探工程公司  北京  100101; 2阿姆河天然气公司  阿什哈巴德  744020
  • 出版日期:2011-05-25 发布日期:2011-07-19
  • 通讯作者: 郭振华
  • 作者简介:郭振华,男,1979年8月生,2006年获吉林大学矿产普查与勘探专业硕士学位,现为中国石油长城钻探工程公司工程师,主要从事测井、测试资料解释和储层评价工作。
  • 基金资助:

    国土资源部国家油气专项(GT-YQ-QQ-2008-2-07)资助。

Pore texture evaluation of carbonate reservoirs in Gasfield A, Turkmenistan

GUO Zhenhua 1  LI Guanghui 1  WU Lei 2  LI Xuren 2  HAN Guiqin 1  JIANG Yinghui 1   

  • Online:2011-05-25 Published:2011-07-19

摘要:

对土库曼斯坦阿姆河右岸气田两种构造类型的碳酸盐岩储层孔隙结构进行了对比评价。结果表明,大背斜构造储层主要表现为孔洞型储层,披覆构造储层主要表现为孔隙型、裂缝—孔隙型储层。对于大背斜构造储层,孔喉中值半径越大,孔喉分布越偏向较大孔喉,呈现“好上加好”的特点。针对碳酸盐岩天然气储层及其开发特点,从动、静态角度以及物性综合指数与毛细管中值压力等试验结果的相关性角度进行分析,提出了评价碳酸盐岩储层的新物性综合指数 Zs。结合毛细管中值压力和新物性综合指数 Zs,将碳酸盐岩储层分为4个级别,并在实例分析中验证了 Zs的合理性和可操作性。应用储层毛细管压力曲线,还原气藏条件下各级别储层的气柱高度,并结合常规测井、成像测井以及地层测试资料研究了储层纵向和区域上的气水分布特征。储层普遍存在气水过渡带,相比于大背斜构造储层,披覆构造储层气水过渡带要更厚一些。裂缝在该区域发育程度和有效性存在明显差异,裂缝及微裂缝对于研究区碳酸盐岩储层求产,尤其是披覆构造储层求产作用关键。

关键词: 碳酸盐岩储层, 物性综合指数, 储层分类, 气水分布, 裂缝, 土库曼斯坦

Abstract:

This research compared and evaluated pore textures formed by two different kinds of structures in carbonate reservoirs in Gasfield A of Turkmenistan. It suggests that reservoirs of mega-anticline structures are characterized mainly by vuggy texture, while those of drape structures mainly showed characteristics of pore texture and fracture-pore texture. As to mega-anticline structures, the larger the medium throat size (corresponding to experimental medium value of capillary pressure), the more obvious tendency of pore throat size distribution to larger size. In view of carbonate gas reservoirs and their special features represented during development, a new aggregative index Zs is proposed to evaluate physical properties of reservoirs based on both dynamic and static texture analysis as well as the correlation of the aggregative index with an experimental medium value of capillary pressure. As a result, carbonate reservoirs can be divided into four grades by integrating the medium value of capillary pressure with the aggregative index. The rationality and feasibility of the index was validated by applying it to example analyses in the evaluation of carbonate reservoirs in Gasfield A. Gas saturation, i.e. gas-column height, was reconstructed under gas-reservoir conditions for each grade of different reservoirs by using capillary pressure curves of reservoirs. Also, the characteristics of vertical and regional distributions of gas and water in reservoirs were examined by combining conventional logging data with image logging data and formation testing data. It was found that a gas-water transition zone was common in carbonate reservoirs, and, when compared with reservoirs of mega-anticline structures, the reservoirs of drape structures generally had a thicker transition zone. The development and availability of fractures in this area showed an apparent regional diversity, and therefore fractures and microfractures play a very important role in gas deliverability in carbonate reservoirs, especially those of drape structures.

Key words: carbonate reservoir, aggregative index of physical property, reservoir classification; , gas/water distribution; , fracture; , Turkmenistan