Rich, attractive and extremely dense: A geophysical review of Australian IOCGs

Anisotropy of Magnetic Susceptibility (AMS) and Paleomagnetism applied to the differentiation of structural and metallogenic controls on Iron Oxide Copper-Gold (IOCG) mineralization: a case study from Monakoff, NW Queensland

“…The remanent magnetisation has a mean declination of 238.4°, and an inclination of -38.6°, which is significantly offset from the present field, and previous measurements in Cloncurry IOCGs (e.g., Clark 1988,1994Austin et al, in press), so it likely formed during deposition, or early in the deformation history e.g., D 1 , D 2 . The relatively low average Q in the magnetite BIF and ore horizon are consistent with previous studies of IOCGs (Clark 1988(Clark , 1994Austin et al, 2012;Austin et al, in press) and indicate that metasomatic fluids precipitated the magnetite in both units. …”

“…Iron Oxide Copper-Gold (IOCG) deposits have a wide variety of geophysical signatures and properties (Austin and Foss, 2012). The metallogenesis of some stratiform types of IOCGs (e.g., Monakoff, Weatherly Creek) is particularly controversial with some authors proposing a primary syngenetic control via seafloor exhalative processes (e.g., Davidson, 1996Davidson, , 2002Hatton and Davidson, 2004) at ca.…”

3D Gravity Fast Inversion Based on Krylov Subspace Methods

“…IOCG deposits have different geophysical characteristics, especially gravity and magnetic data. The Olympic Dam has a more obvious gravity anomaly than the magnetic anomaly (Austin et al, 2012). The Olympic Dam deposit includes a large amount of magnetite, hematite or semi-biological minerals and is, thus, affected by iron oxides.…”

Geophysical vectors to IOCG mineralisation in the Gawler Craton

“…The geophysical responses of individual IOCG deposits and prospects have been documented at Olympic Dam (Esdale et al, 2003), Prominent Hill (Hart and Freeman, 2003), Carrapateena (Vella and Cawood, 2012) and Wirrda Well (Vella, 1997). Smith (2002) provides an overview of the geophysical responses from IOCG's that is purposely broad to encompass a wide range the IOCG related deposits, Austin and Foss (2012) modelled the gravity and magnetic response of a number of Australian IOCG deposits and Gow et al (1993) provides detail on interpreting the geology and IOCG alteration beneath the Stuart Shelf sediments from magnetic and gravity datasets.…”