The Leonora Gold Project is located within the Norseman-Wiluna Greenstone Belt which comprises volcanic and sedimentary rocks that were deposited around 2.7Ga, multiply folded, metamorphosed to low or medium grade, extensively intruded by granitoids and subjected to major faulting along northerly to north-northwesterly trends.
The dominant structural feature in the Project area is the Mertondale shear zone which is a northerly striking structure linking the north-northwesterly trending Keith-Kilkenny and Celia Lineaments. The Mertondale shear zone has a total strike length of 90km of which some 20km lies within Navigator’s tenements. Gold mineralisation is structurally controlled within the shear zone and can be associated with:
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dilational, flat dipping intershear quartz-sulphide lodes as at Merton’s Reward;
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zones of high competency contrast along a porphyry-metabasalt contact as at Mertondale 3-4; and,
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as steeply dipping dilational zones along the western branch of the shear zone as at Quicksilver, Tonto, Eclipse and Mertondale 5.
Plunges of individual mineralised zones are often sub-horizontal as at Mertondale 5, whilst the Merton’s Reward lodes have a moderate northerly plunge and easterly dip.
The resources at Cardinia are contained within a sub-horizontal supergene zone lying within 50m of the surface. The mineralisation transects all rock types in the area and to date no significant primary mineralisation has been defined.
At Raeside, the mineralisation is hosted by mafic and sedimentary rocks and occurs as multiple weak stockworks or sheeted vein zones. The veins are predominantly quartz or quartz-carbonate, accompanied in the primary zone by disseminated to stringer sulphides. The lodes have a generally moderate dip to the north-east.