An integrated study of remotely sensed and geophysical data for mineral exploration in Lincoln County, Nevada
The mineral belts of Lincoln County, which comprise the Pioche mineral belt, and the Delamar-Iron Springs (sub) belt, were studied using geophysical and remote sensing data. A general objective of the project was to develop a procedure for integrated investigation using remotely sensed and geophysical data for mineral exploration in arid to semi-arid regions. Particular emphasis was placed in determining the relationships between the data sets, the adequacy of spatial and spectral resolution of the sets, and optimum use of the multi-type data sets in mineral exploration. The multi-type data sets used in this study can be divided into three categories: remote sensing, geophysical and GIS-based data. Digital Thematic Mapper (TM) data were processed in a maximization technique that discriminates hydrothermal alteration from the other cover types in the area. This technique is robust, appears to be scene independent, and resulted in the discovery of previously unknown areas of hydrothermal alteration. A new technique, n-dimensional probability density functions (nPDF) which is an algorithm for displaying, analyzing and classifying multi-dimensional data, was developed in order to classify the data interactively. Lineament analysis was carried out using a variety of filters on the TM data. Gamma-ray, as well as aeromagnetic and gravity data were used to identify the specific attributes of known mineral deposits in order to outline other potential target areas. The combined analysis of the geophysical data using Internal Correspondence Analysis (ICA) showed east-west trends in the study area. It is believed that the mineral belts in the area are controlled by these east-west trending structures. The intrusive rocks in the area are associated with a negative ICA correlation coefficient. Quantitative integration of the TM and geophysical data sets was done using the nPDF classification technique. This quantitative analysis technique provided an excellent strategy for mineral exploration in the study area. It resulted in discovery of five prospects having the characteristics similar to the Delamar and Pioche Districts.
Levandowski, Purdue University.
Off-Campus Purdue Users:
To access this dissertation, please log in to our