Method for Calculating Mineral Component Content and Porosity of Shale Gas Formation

Abstract

The invention discloses a method for calculating the mineral component content and porosity of a shale gas formation, comprising the following steps: calculating the total clay mineral content by using conventional comprehensive logging data, decomposing and calculating the content of three different types of clay minerals, Calculate the organic matter content, and then calculate the pyrite content; correct the log value of the logging curve; log results without element capture, and return to the mineral content of carbonate rocks according to the regional relationship established by the comprehensive logging data; with element capture The logging results directly use the element capture logging results for carbonate rock mineral content; the optimization and constraint calculation of quartz, feldspar, calcite, dolomite minerals and porosity; and the normalization of calculation results. The invention realizes the calculation of various mineral component contents of shale gas formations by well logging data, improves the calculation accuracy of complex mineral component contents and porosity of shale gas formations, and provides accurate calculation of brittleness index and shale gas formation The gas content of the gas formation provides a basis.

Description

technical field [0001] The invention relates to a method for calculating the contents of up to nine kinds of minerals and the size of porosity in a shale gas formation by using logging data, and belongs to the field of logging data interpretation and evaluation in oil and gas exploration. Background technique [0002] Shale gas is an unconventional oil and gas reservoir. The shale gas formation is composed of lithological minerals and pores (fractures). The lithological particles are not only much finer than the conventional sandstone formation, but also the mineral diversity of the formation is complex. , except for a small amount of minerals with low content, it generally mainly includes clay (illite, chlorite, montmorillonite), quartz, feldspar, calcite, dolomite, organic matter (kerogen), pyrite, etc. The logging response characteristics of each mineral component vary greatly, and the content of each mineral component varies greatly in each shale gas development block. T...

AI Technical Summary

Problems solved by technology

[0005] 2. Domestic methods for calculating complex minerals using logging data for shale gas formations are immature. Quartz and feldspar are classified as siliceous minerals, calcite and dolomite are classified as carbonate minerals, and different types of clay minerals are classified as A clay mineral, although the calculation method is simplified, the result cannot correctly reflect the characteristics of the real mineral composition in shale gas formations

[0006] 3. Foreign logging companies represented by Schlumberger rely more on formation element capture logging data when calculating the complex mineral components of shale gas, and cannot calculate the corresponding complex mineral composition

[0007] 4. It is very difficult to accurately calculate the content and porosity of complex mineral components when there are only conventional comprehensive logging data