Geostatistical investigation of RQD to identify the high permeable zones in the Takht-e-Gonbad copper mine pit,, Sirjan

One of the most important problems in mining is the flow of groundwater into the pit mines. The location and amount of these waters are often dependent on the permeable zones. Therefore, geostatistical methods can be used to identify these zones. Hence, geostatistical research has been done on variable data of the rock quality designation (RQD) to identify permeable zones in the area of Takht e- Gonbad copper mine pit, Sirjan. This mine is located in Kerman province, northeast of the Sirjan city and it is an open-pit type. A total of 69 exploration boreholes have been dug in the area around the pit. During the drilling, the variable data of the RQD was recorded during a spatial distance of 3 m along the entire length of the boreholes. Identifying areas with high permeability in the rock units of the region, especially in the subsurface of the aquifer, is necessary to carry out the drainage plan in the future. In this research, geostatistical simulation methods have been used to identify permeable zones. The results of the preliminary statistics showed that the RQD has an increasing trend with increasing depth. The spatial continuity of the RQD based on the directional variogram and the spherical model was estimated about 81 meters, and was greater in the east-west direction. Finally, by geostatistical simulation, the areas with high permeability in the region have been determined which are mainly located in the northeast and southwest of the pit.