Annual Report for EL 4841 Golden Dyke year ending 03-12-1987

Abstract

Exploration Licence 4841 is situated on the southeastern margin of the Golden Dyke Dome. The geology consists of metamorphosed pelitic sediments containing exhalative horizons (chert, banded iron formation, tourmalite) interlayered with thick sills of metamorphosed mafic rocks. These strata belong to the Koolpin Formation and Zamu Dolerite of early Proterozoic age. They are folded into southerly plunging anticlines and synclines which are subsidiary structures on the main dome.

Geological mapping and geochemical soil surveys carried out in 1986 disclosed anomalous gold and arsenic associated with banded iron formations at three localities. This raised the possibility of mineral deposits similar to those mined at Golden Dyke and Black Rock which occur at the same stratigraphic position on the west side of the dome 2000 - 3000 metres to the northwest. These results were followed up in 1981 by programmes of detailed grid survey, geological mapping, soil and rock-chip sampling and trenching. At Shady Camp anomaly three trenches on the west limb of a south plunging anticline encountered gold values in banded iron formation over a strike length of 200 metres. This is considered to be the same formation as that containing the Golden Dyke orebody situated 700 metres to the northwest. The best results were in the most northly trench which averaged 1.39 g/t Au over 7 metres, with a maximum of 5.5 g/t over the one-metre sampled width. This zone has a potentially mineralised strike extent of 400 metres. Trenching on the east side of the fold showed that the potentially mineralised horizon was faulted out at surface but may be present at shallow depth. At Rockwall anomaly three trenches were excavated along a strike length of 375 metres. The potentially mineralised BIF horizon proved to be thin and only weakly m mineralised. Results at the Shady Camp suggest a potential for moderate tonnages of low grade oxidised open pit ores. A small drilling programme is warranted to obtain a better indication of the grade of the mineralisation.