New Method for Calculating Rock Particle Size Composition Parameters

The application of the conventional arithmetic mean method to calculation of the rock particle size composition parameters is limited to the normal type of distribution and may result in high error of calculated parameters. In view of this, a new method to calculate the rock particle size composition parameters is proposed in this paper. The method was called “a weighted mean method.” A detailed theoretical basis for the new method is presented, and the calculation formula expressions are derived. The calculation process is demonstrated with an example. In order to verify the accuracy of the new method, the calculation results are compared with those of the conventional arithmetic mean method. It was shown that the new method can be applied to calculate rock particle size composition parameters in cases where the granulometric parameter distribution is unknown or differs from normal distribution. The results show that the proposed method is more accurate and widely applicable.