Computer programs for the assessment of coal resources (ver. 2.0, April 2021)

The USGS assessment and methodology reports cited within this software release require extensive processing using computational methods and modeling. The most demanding aspects of the modeling were performed using publicly available software: SGeMS and GSLIB (See the 'related External Resources' section on this webpage to learn more about this software). This publication releases the FORTRAN source code of 15 supplementary computer programs that are required to perform the more specific aspects of the modeling. Upon downloading a program, the user needs to use a FORTRAN compiler for generating the executable code. The tasks performed by these FORTRAN programs are: blankgridsis, for blanking of several realizations of an attribute according to as many sequential indicator realizations of coal bed presence/absence; coverclass, for classification of cell cover into 4 classes intended to be used for determining mineable resources; decluster, for declustering of data with preferential sampling; dif2sur, for calculation of thickness between a deterministic surface, such as surface elevation, and several realizations of another attribute, such as the top of the oxidation zone; EtypeSGeMSsis, for preparation of grids for nine statistics node by node; g2gtrim, for blanking one grid based on the information of another, typically an SGeMS simulation file based on kriging standard error; kvar2ksd, for replacing the second of 2 columns by its square root, which is useful to convert variance to standard deviation in kriging grid; mining, for modeling mineable coal resources for both surface and deep methods; multgridconst, for multiplying a grid by a constant; pinchout, for wedging out realizations of coal seam thickness inside a convex polygon specified by the user; reliabcurve, for tabulating cumulative tonnage cell by increasing 5-95 spread; resourcesCsis, for calculating total coal resources per tonnage realization; thick2ton, for converting thickness realizations to tonnage realizations; trim, for blanking of file records base on the information of one column in the same file.