Generalized model for evaluating area-potential in a mineral exploration program. A case study of silver exploration in parts of Idaho and Montana

A cellular approach is adopted and each two-degree quadrangle is divided into 512 cells. The model is developed in three independent stages. The first stage consists of identifying a useful database and transforming it into a computer processable form. National Uranium Resource Evaluation (NURE) stream-sediment data, the Geological highway map of the Northern Rocky Mountain region, a residual magnetic anomaly map of Butte quadrangle and mining data are identified as the database. The database is transformed into a computer processable form by digitizing the data over each cell. In the second stage, control cells are selected from the Butte quadrangle by two a priori subjective models using multiple linear regression and filtering techniques. These control cells are used for developing weighting factors for computer-transformed variables. The evaluation and prediction of cells are made in the third stage, wherein the products of weighting factors and corresponding transformed variables are added to give a probability score for each cell. A maximum of 10% of the cells are selected as predicted cells, and checked for mining in the cell areas by comparing them with the mining database. A total of 160 cells are selected as predicted cells from the area, of which 61 were identified as confirmed cells having mining within their cell areas. These 61 cells, constituting 38.13% of the total predicted cells, are classified as first order prospects. The remaining predicted cells are classified into 76 second order, and 23 third order prospects based on further inspection of cell areas in 1:250,000-scale geological maps and 7.5-minute topographic maps