Outlining of high quality coking coal by concentration–volume fractal model and turning bands simulation in East-Parvadeh coal deposit, Central Iran

•Using turning bands and C–V fractal modeling in coal seams•Reproduction of 100 realization for ash and sulfur in coal seams•Categorization of coal seams for ash and sulfur by fractal modeling•Correlation between fractal and geological modeling

This study aims at identifying the proper parts of C1 and B2 coking coal seams in the North block of East-Parvadeh coal deposit (Central Iran) using the concentration–volume (C–V) fractal modeling according to sulfur and ash values which were calculated by turning bands conditional simulation. The C–V log–log plots were generated based on results of 100 realizations derived via turning bands simulation which show seven different geochemical populations for both sulfur and ash data in B2 seam which has a relatively good quality for coking coal with sulfur and ash values lower than 1.548% and 6.39% respectively. Additionally, C–V log–log plots indicate that there are seven and six for sulfur and ash geochemical populations in C1 seam containing a proper coal quality with respect to sulfur and ash values less than 1.41% and 6.92% respectively. High quality populations are located in the northern and western parts of the studied area which correlated with USGS standard. The logratio matrix was used for the correlation between results obtained by the C–V fractal modeling and geological particulars consisting of pyritic veins and ash coals. Based on the logratio matrix for sulfur values higher than 3.55% and 3.39% for C1 and B2, respectively, low quality parts of the seams have good correlation with pyritic veins in the eastern and central parts of the area. Moreover, there are high values of overall accuracy (OA) for correlation between parts of the seams with high values of ash which are 47.86% and 39.81% for C1 and B2, respectively, and ash coals obtained by geological data.