Analyzing the mid-low porosity sandstone dry frame in central Sichuan based on effective medium theory  

基于等效介质理论分析川中低孔砂岩的骨架结构分析(英文)

作　　者：晏信飞[1,2] 姚逢昌[1,2] 曹宏[1,2] 巴晶[1,2] 胡莲莲[3] 杨志芳[1,2] 

机构地区：[1]中国石油勘探开发研究院物探技术研究所,北京100083 [2]中国石油天然气股份有限公司地球物理重点实验室,北京100083 [3]中国地质大学(北京),北京100083

出　　处：《Applied Geophysics》2011年第3期163-170,239,共9页应用地球物理（英文版）

基　　金：supported by the National Natural Foundation of China (No. 41104066);the Basic Research Programs of CNPC during the 12th Five-Year Plan Period (No. 2011A-3601);the Major State Basic Research Development Program of China (No. 2007CB209505);RIPED Young Innovation Foundation (No. 2010-A-26-01)

摘　　要：Tight gas sandstone reservoirs in Guang＇an are characterized by wide distribution and low abundance. Sandstone samples from this area usually have low porosity and poor connectivity. We analyze the observed velocity data of tight sandstone samples with the Mori- Tanaka model, and give the sandstone framework physical model in this area based on theory and experiment analysis. The matrix modulus was obtained by an empirical relationship and then the experiment data were compared with the values predicted by the Mori-Tanaka model with different pore shapes. The results revealed that the experiment data were close to the model with low pore aspect ratio. Considering the matrix modulus and pore shape variation, we find that, under the condition of small mineral composition change, the effective pore aspect ratio of these samples increased with porosity evidently.川中广安地区的致密含气砂岩储层具有分布广,丰度低的特点。采自该地区的砂岩样本孔隙度普遍偏低,孔隙连通性差。本文采用Mori-Tanaka模型分析致密砂岩样本的波速观测数据,基于理论与实验分析,给出了该地区砂岩骨架的物理模型。通过经验关系获取基质模量,将实验数据与Mori-Tanaka模型在不同孔隙形态时的预测值进行对比,结果显示实验数据与低纵横比的软孔模型比较接近。综合考虑基质模量和孔隙形态变化的影响,分析表明在矿物成分变化不大的情况下,样本的等效孔隙纵横比随孔隙度增加有上升的趋势。

关 键 词：tight sandstone dry frame Mori-Tanaka model pore aspect ratio INCLUSION 

分 类 号：P618.13[天文地球—矿床学]