A new survey design for 3D IP inversion modelling at Copper Hill

Abstract

The Copper Hill prospect in NSW is a porphyry copper/gold system. Geochemical and gradient array IP results suggest that grid northwest and grid northeast structural directions control the location of mineralisation. Previous drilling has been oblique to these directions. The known sulphide rich mineralised zones exhibit moderate to strong IP responses. An IP/resistivity survey was conducted to produce a detailed 3D mineralisation model for Copper Hill. 3D inversion of IP data is considered suitable for mapping the sulphide horizons in detail. The use of 3D-inversion modeling techniques, accepting a modified pole-dipole IP survey array, allowed an electrode array to be designed for fast acquisition of a large quantity of data. The use of modified pole-dipole arrays extend the effective depth of investigation of IP surveys as well as improving the across line resolution. Inversion results delineated the three dimensional form of sulphides zones at Copper Hill.