Time domain spectral IP results from three gold deposits in northern Saskatchewan

CIM Bulletin, Vol. 82, No. 922, 1989

lan Johnson and Blaine Webster, JVX Ltd., and Ron Matthews and Steve McMullan, Cameco

Time domain spectral Induced Polarization (IP) data from the Tower, Jojay and Laurel Lake gold deposits in northern Saskatchewan are presented. The resistivity data shows both resistivity lows (due to fault, shear or alteration zones) and resistivity highs (due to silicification) in the area of the deposits. The high resistivity zones suppress and distort coincident IP responses, calling for high quality surveys and special care in interpreting the IP data. Electromagnetic methods are not effective in locating the deposits. This is due, in part, to masking by conductive cover. The Jojay Lake deposit has a strong magnetic response. A more indirect magnetic association is seen for the Tower Lake deposit. The Laurel Lake deposit has no magnetic signature. Magnetic data are useful in defining structure in all cases. All three deposits are outlined in the IP survey results. IP anomaly amplitudes from the pole-dipole array are from two times (Tower and Laurel Lake) to six times (Jojay Lake) background values. Gradient array IP anomalies are of less amplitude. The spectral time constant is short for the Tower and Laurel Lake deposits and long for the Jojay deposit. This implies that the metallic sulphides in the Jojay deposit are more interconnected than those of the other two deposits.

Keywords: Exploration, Gold deposits, Induced polarization (IP) methods, Tower Lake deposit, Jojay Lake deposit, Laurel Lake deposit, Spectral IP