定量交会图技术及其在流体识别中的应用

Application of quantitative crossplot technique in fluid identification

(1.成都理工大学信息工程学院，四川成都610059；2.中国石油四川石油地球物理勘探物探研究中心，四川成都610213)

College of Information Engineering, Chengdu University of Technology, Chengdu 610059, China

交会图技术是地震资料解释的有效手段之一。但是，交会图域内的区域划分常采用粗略描述或人工勾绘，这实际上是一种定性分析方法，存在很大的不确定性。为解决这一问题，提出了一种定量交会图分析技术。首先对交会图域内各类储层数据进行椭圆拟合，自动生成各类储层数据的空间展布；然后计算平均拟合度和重叠率这2个定量参数，对储层类别进行定量描述；最后应用基于椭圆拟合的流体属性敏感性分析方法，利用Castagna和Smith的含油气砂岩模型进行了流体属性可识别性分析，并优选出对含气砂岩敏感的流体属性对。

The crossplot technique is one of the effective methods for seismic data interpretation. However, for partitioning the cross-plot region, rough description or hand drawing is usually adopted, which is a qualitative analysis, making uncertainty exist. To solve this problem, the quantitative crossplot technique is proposed. Firstly, the ellipse fitting is performed for data from different kinds of reservoirs in cross-plot region to automatically generate the spatial distribution of data. Then, the average fitting degree and overlap rate are calculated to quantitatively describe the reservoir category. Finally, the fluid attribute sensitivity analysis method based on ellipse fitting is adopted. Fluid attribute identifiability was studied by using the oil sand model from Castagna and Smith and fluid attributepairs sensible to gas bearing sand were optimized.