The Mt Garnet area is located in the far south-west corner of the Hodgkinson Province which forms a 500km-long belt of Early- to Middle-Palaeozoic turbiditic sediments, with generally subordinate limestone, chert and basic volcanics that lie to the east of the Palmerville Fault. The Palmerville Fault is a major fault zone in NE Queensland along which Palaeozoic rocks to the east are juxtaposed against Proterozoic rocks to the west. Silurian-age Chillagoe Formation rocks, characterised by limestone, chert, basic volcanics and siliciclastics, lie along the western margin and at the base of the Hodgkinson Province. Limestones of this formation are favourable hosts for skarn-associated zinc mineralisation as demonstrated in the Mt Garnet district by the Mt Garnet and Bald Hill deposits.
Regionally, Permo-Carboniferous igneous activity resulted in emplacement of extensive granitic plutons and widespread eruption of sub-aerial felsic volcanic sequences.
Kagara Ltd’s EPM’s largely cover Siluro-Devonian Chillagoe Formation rocks with intrusive stocks and small plutons of Permo-Carboniferous granitoids in the northernmost sub-blocks. Sub-aerial felsic volcanic rocks of the Nanyetta Volcanics infringe onto the northern and north-eastern sub-blocks, and a small outlier of felsic volcanics lies on the southern side of Mt Garnet.
In the immediate vicinity of Mt Garnet and the Mt Garnet ore body environs; there is an inlier of the Proterozoic Halls Rewards Metamorphics east of the Chillagoe Formation, bound to the west by a mylonitic fault zone, which is interpreted as an expression of the Palmerville Fault. This mylonitic zone forms the eastern limit of mineralised skarns associated with the Mt Garnet zinc-rich ore body. Mafic rocks, chert and siliciclastic rocks along the mylonite zone may represent mylonitised Chillagoe Formation strata in contact with gneissic granite immediately to the east, which is interpreted as part of the Halls Reward Metamorphics.
Mineralisation in the district includes skarn-associated zinc (e.g. Mt Garnet and Bald Hill deposits), copper, lead, iron and fluorite (e.g. Wriggly Prospect), granite-hosted vein deposits of tin and tungsten, and porphyry-related gold mineralisation. The Mt Garnet district was one of the world’s major producers of alluvial tin, particularly over the period of 1939 to the early 1980’s.
Exploration in the Mt Garnet district over the next 12 months will focus on:
Soil sampling and geological mapping by Kagara Ltd and previous explorers has identified several prospects with highly anomalous base metals in soils with associated skarn alteration akin to the alteration at Mt Garnet. These are:
