Article quick-view

Remote sensing and GIS prospectivity mapping for magmatic-hydrothermal base- and precious-metal deposits in the Honghai district, China

ABSTRACT

In this paper, we constructed an exploration target model for volcanogenic massive sulfide and hydrothermal deposits in Honghai district (China) using moderate resolution ETM+, ASTER, and hyperspectral Hyperion images and high resolution ZY-3 images, and weights-of-evidence (WofE) analysis and concentration-area (C-A) fractal modeling. The methodology and mapping steps were: (1) ETM + images were used to extract hydroxyl and iron-oxide alterations for identification of linear and ring fault structures and prospective zones in regional scale; (2) ASTER images were used to extract SiO2 index, kaolinite, chlorite, propylite, potassium, carbonate, and limonite alterations for identification of mineralization zones in district scale; (3) hyperspectral Hyperion images were analyzed to identify mineral components for identification of Cu<img border="0" alt="single bond" src="http://cdn.els-cdn.com/sd/entities/sbnd" class="glyphImg">Au deposit zones in district scale; (4) high resolution ZY-3 images were used to extract geological objects (e.g., volcanic rocks, integration, and linear and ring fault structures) and cross-validate multiple type alterations and their associations with lithological strata based on interpretation of ETM+ and ASTER images; (5) alteration/structural factors and geological objects were integrated for mineral prospectivity mapping by WofE analysis, and mineral prospectivity was classified by (C-A) fractal modeling. Ring faults, iron-oxide alteration, chlorite alteration and silicification are important exploration factors, whereas carbonate alteration, potassic alteration, and linear faults are secondary exploration factors. Ten exploration targets were recognized in the Honghai district.

8 FIGURES