Constraints of deep crustal structures on large deposits in the Cloncurry district, Australia: Evidence from spatial analysis

Abstract

Deep structures are commonly recognized as critical factors for controlling the formation of large hydrothermal deposits. It is of great importance for the metallogenic studies to quantitatively describe the spatial associations of deep structures with mineral deposits. In the Cloncurry district of the Mt. Isa Province, Australia, many large deposits have been discovered and district-scale deep structures have also been recognized from the magnetic, gravity, seismic and magnetotelluric data. In this paper, we delineate the 3D configuration of the deep structures by 3D geometric modeling and Gaussian curvature analysis, and quantify spatial associations of the deep structures with the large deposits by the weights of evidence method. The results demonstrate that the configuration of deep structures has a positive spatial constraint on the distribution of deposits. Many deposits are located close to the high curvature portion of the deep structures. According to this rule, there are some potential target areas where curvature of the deep structural surfaces is high but no deposits have been discovered. Such results can be used to identify targets with potential for finding undiscovered deposits.