Quantitative analysis of clay minerals

1、The following formula is used to calculate the total amount of clay minerals and the content of various non clay minerals:

In the formula:

Xi——percentage of mineral i (wt%);

Ii——selected integral intensity of diffraction peak in mineral i;

Ki——Reference strength of mineral i;

2、Determne of the relative content of clay minerals:

Firstly, pure clay minerals are extracted from rocks to prepare oriented slices. X-ray diffraction was performed.

Then calculate the relative content of various clay minerals.

The diffractive rays with specific diffractive index of various clay minerals are selected, and their intensities are determined. The relative content is determined according to the proportion of their intensities in the total intensities and intensities of diffractive rays of various clay minerals.

3、Determination of order degree of dolomite

Read the integral intensity I (015) of the diffraction peak [D (015) = 0.2540nm] of dolomite (015) crystal plane and the integral intensity I (110) of the diffraction peak [D (110) = 0.2405nm] of dolomite (110) crystal plane respectively, and calculate the order degree of dolomite according to the following formula:

In which:

δ——order degree of dolomite

I(015)——Intensity of diffraction peak (015)of dolomite

I(110)——Intensity of diffraction peak (110)of dolomite

4、Implementation standard:

SY/T5163-2018 Analysis method for clay minerals and common non-clay minerals in sedimentary rocks by the X-ray diffraction