Estimativa de teor por uso de inverso da potência da distância: caso do ouro Filão da Porteira- MT

Abstract

In the northern region of the State of Mato Grosso there are many gold mines, where they have a significant participation in gold mining in the State; these mines often do not carry out a detailed and indepth study of the deposit, thus generating a loss for the garimpeiro. The Alta Floresta Aurífera Province (PAAF) is located in the Amazon Craton, in an elongated area in the W-NW direction. The Filão da Porteira deposit is housed in Monzogranito Buriti, which corresponds to whitish gray gray gray monzogranite, uneven, thick, isotropic, locally banded and foliated. The ore of Filão da Porteira is composed of gold, pyrite and chalcopyrite, being hosted in quartz veins with thickness varying from 0.2 to 1.5 m, with preferential direction N15W and diving ranging from 60 ° to 85 ° NE. To estimate the gold content at the site, a treatment and validation of the drilling holes provided by Coogavep was first used, followed by a statistical and geostatistical study. The conventional Inverse of Distance Power (IPD) technique was then adopted, making it possible to obtain an estimated reserve value of 625 kg of gold, which represents an estimated market value of R $ 187,273,931.00 reais. The cross validation, associated with the IPD estimate, provided an error of -4.290255, which is considered excessive, since the error or residual of the estimate (difference between estimated and real value)must be close to 0.