Estimasi Sumberdaya Untuk Data Dengan Distribusi Lognormal Pada Endapan Urat Emas Gunung Pongkor Dengan Pendekatan Geostatistik

  • Idris Herkan Afandi Institut Teknologi Bandung
  • M. Nur Heriawan Institut Teknologi Bandung

Abstract

This study aims to determine the method of estimation and data processing are suitable to the
lognormal distribution data. Data obtained from the assay data of gold vein mineralization from
Gunung Pongkor, West Java. Data provided are relatively only a few or not proportionate to the
volume of mineral bodies, range of space (average 50 m to the north), as well as lognormal
distribution data. Data collection was enlarged by conducting composites within 1 m, resulting in
828 points. Furthermmineral, the data is divided into the data without a top cut and the data with
a top cut, for the benefit to estimate data also has been transformated into logarithm. Variogram
modeling performed on each data to get a geostatistical parameters. The estimation method that
used are methods such as of Ordinary Kriging (OK), Lognormal Ordinary Kriging (OLK) and
Sichel's t-estimator. The criteria used suitably is the correlation coefficient value estimation results
with actual levels valued mmineral than 0.6. Assumptions for the best method is the method that
has the best accuracy between the regression line with line bisector and for the method that has a
variance estimation is a method which has an average smallest variance estimation. The cumulative
distribution curve estimation results show the difference in the results of the estimates using the
data without a top cut and the data with a top cut. This research resulted in the values of the
correlation coefficient from the three methods are mmineral than 0.6. The most appropriate
regression line with a line bisektor is Lognormal Ordinary Kriging method (OLK) both use the data
without a top cut and the data with a top cut and the average of smallest variance estimation is a
method of Ordinary Kriging (OK) that use data with the top cut.

Author Biographies

Idris Herkan Afandi, Institut Teknologi Bandung

Fakultas Teknik Pertambangan dan Perminyakan Institut Teknologi Bandung

M. Nur Heriawan, Institut Teknologi Bandung

Fakultas Teknik Pertambangan dan Perminyakan Institut Teknologi Bandung

Published
2018-04-02