Annual Report for EL 3504 and EL 3505 year ending 20-04-1986

Abstract

During 1985, CSR Limited carried out an exploration programme for gold within Exploration Licences (EL's) 3504 and 3505. The programme consisted of geological mapping, airborne and ground geophysical surveys, and soil and rock- chip geochemical sampling. Two sills of the prospective host rock, the Zamu Dolerite, are present. A total of 1,200 soil samples were collected along regional soil lines. Several arsenic anomalies were defined. Anomalous zones were assigned priorities according to their geological association. Composite soil samples from the anomalous arsenic zones defined several intervals containing anomalous gold. One rock-chip sample from an outcropping altered ultrabasic unit assayed 0.2 ppm Au and 101 ppm As. High As values (maximum 1.59%) were obtained from outcropping Koolpin Formation on lines B23 and B24. Geological mapping, rock-chip and soil sampling were completed along sections of the Darwin to Amadeus Basin gas pipeline trench. Further work is recommended. The high-priority arsenic soil anomalies should be checked by a programme of geological mapping, rock-chip sampling and, if warranted, trenching. Lower-priority anomalies should be evaluated by rock-chip sampling.