The Mt Carlon project was originally identified during a regional review to identify potential mafic intrusions that may host magmatic nickel-copper-cobalt sulphide mineralisation.
There are two conceptual targets within Mt Carlon. The first is an area of strong geophysical magnetic and gravity response on the eastern side of the greenstone belt which may represent a large mafic intrusion. The second is an ultramafic unit mapped over 7km of strike in which historic drilling has identified elevated nickel and copper values.
In mid-2019 Great Boulder completed an airborne EM survey over the tenement looking for possible sulphide bodies. This resulted in the identification of two large, elongate anomalies labelled the Western Zone anomaly and the Eastern Zone anomaly.
The Western Zone is a 3.7km conductive anomaly which coincides with mapped Banded Iron Formation (BIF). Because BIF is not a conductive unit, the anomaly may be caused by sulphide minerals within the BIF unit in a fault-bound dilational setting. This environment is prospective for gold mineralization.
Although the Western Zone has had some historic coverage with RAB drilling, the hardness of the BIF means it is unlikely to have been effectively tested.
The Eastern Zone anomaly is a 3.5km linear feature which displays a chargeable effect or “IP Effect” in the EM data. In this sense it is not a conductive anomaly but rather a capacitive or chargeable anomaly. Such effects are characteristic of disseminated sulphides or chargeable clays such as montmorillonite; however the shallow cover and limited weathering in this area indicate that clays are not the cause of this anomaly.
The Eastern Zone is also coincident with elevated nickel geochemistry, as intersected in aircore drilling, and it sits above a mapped ultramafic unit. This coincidence of geology, geochemistry and geophysics makes the Eastern Zone a high priority for nickel exploration.