Zonia Copper Oxide Project, Arizona
Geophysics
IP & Resistivity Survey
In January and February 2018, HydroGEOPHYSICS, Inc. (HGI), of Tucson, Arizona completed 28 line kilometres of Induced Polarization (“IP”) and Electrical Resistivity (“ER”) on the Zonia project. Coincident IP and ER data were collected to characterize the extent of chargeable sulfides under the area of drill-defined mineralization, and then apply this information to outline other possible subsurface mineralization on the property. The IP method was selected to take advantage of the charge-storage capability of the sulfides that are known to underlie the copper oxide resources. ER measurements were recorded coincident with the IP measurements during this survey, as the ER data provides valuable context for the IP data and information on subsurface structure. The data were collected at 200m (n=1) dipole spacing to a maximum of n=6 spacing between measurements.
Depth slices at the 1000, 1100, 1200, and 1300-meter elevations show an increase in chargeability with depth, matching observations in the drill holes of sulphides underlying the copper oxide mineralization in this area. The IP response increases in magnitude in the depth slice from the 1,100-meter elevation, with the highest values towards the southwest end of the survey area. The chargeable body is clearly observed trending across the survey area in a NE-SW direction, with highest magnitude IP responses noted in the southwest and the response dropping off toward the northeast. The top of sulphides (or base of oxidation) is known from the drilling to dip down to the northeast, and this is well reflected in the IP data.
The area of overlapping chargeability and copper-molybdenum anomalies extends about 600 metres from the current Whittle pit defined resources. Half of this area has been sparsely drilled by holes targeting copper-gold structures, with the southeast half (up-dip from the chargeability) untested. This area will be tested during the future feasibility study in-fill drill programme.
The Northeast geochemical anomaly was only covered at its margins by widely spaced lines, which did not detect sulphides (i.e. a chargeability anomaly) down to depths of 300 metres. This suggests the area is deeply weathered and a good copper oxide porphyry target.
