Summary:
Geology comprises typical Archaean Yilgarn greenstone belt lithologies and granitic intrusives. Two main styles of mineralisation are present, typical Yilgarn Archaean lode gold and volcanic massive sulphide (VMS) base metal and gold mineralisation within the Eelya Felsic complex. A crustal scale shear, the Cuddingwarra Shear, truncates the western edge of the project. Structural complexity is common at Cue with the area dominated by local scale shears, notably the Lena Shear. The geology is generally subvertical and include a range of igneous units (basalts, dolerite, granite, etc.), banded Iron formations and felsic sediments. Gold mineralisation most typically occurs as steep dipping (+70°), thin (2-10m) lodes with a range of orientations driven by local structural controls.
Cue sits on greenstone sequences transacted by the Cuddingwarra Shear to the west. Second order shearing (Lena Shear) is the dominant feature through the Project which hosts lower grade mineralisation. High grade mineralisation is generally hosted within brittle units between ductile lithologies. Then there are smaller resources throughout Cue which are hosted in several lithologies including BIF and sheared, high-magnesium basalts.
Mineralisation in the BOD and White Heat (WH) areas is found in the Starlight Basalt stratigraphic unit. The area has experienced alteration associated with the BOD Shear Zone, which trends N-S parallel to the stratigraphy. Veining exists both parallel to, and oblique to the main shear zone, leading to the interpretation of a multi-stage development history, with a complex gold distribution.
Lena mineralisation is associated with the Lena Shear, a 100m wide zone of deformation, to the west of and parallel to the BOD Shear Zone. The Lena Shear Zone consists of a highly strained sequence of high-magnesium basalts, ultramafics and iron rich sediments that have been intruded by numerous phases of felsic dykes.
The Big Sky mineralisation comprises quartz lodes hosted within a foliated and altered sedimentary and mafic stratigraphic sequence and intruded by felsic porphyries. Discrete zones of mineralisation are typically 1m to 15m in thickness and strike north-south. The gold mineralised zones typically dip steeply to the west. A total of 53 separate mineralised zones were interpreted.
Mineralisation at Amarillo occurs in the sedimentary and felsic package located to the west of the Lena Shear Zone. The Amarillo Resource is found on the same trend as the Big Sky Resource to the south.
Mineralisation at the Leviticus deposit is typically 1-8m wide, independent of rock type and is hosted within foliated mafic rocks, with minor felsic intrusions. Mineralisation at Leviticus dips steeply to the east and no plunge has been identified. The deposit has a strike length of just under 200m and extends 120m below surface. Weathering occurs to a depth of 20-45m, and fresh rock commences 5-10m deeper. Most of the deposit is in oxidised or partially oxidised rock.
The Waratah deposit is approximately 400m east of Break of Day and runs parallel to the Lena-BOD corridor. The mineralised trend is interpreted to extend for over 1.2km of strike, with gold mineralisation identified in multiple separate zones, the longest continuous zone is approximately 400m in strike. The mineralisation is dipping steeply west and hosted within a BIF, the mineralisation is typically hosted within the hanging wall and footwall. The BIF is part of the ultramafic and dolerites sequence typical in the area. The deposit remains open down plunge. Weathering occurs to a depth of 20-45m, and fresh rock commences 5-10m deeper. Most of the deposit is in oxidised or partially oxidised rock.
Dimensions
- Break of Day: NW-SE striking with lengths of 50- 130m, a steep (+75°) dip to the SW and thicknesses of 2- 12m, and N-S striking with lengths of 30- 190m, a steep (+80°) dip to the East and thicknesses of 2- 8m.
- White Heat: NWSE striking with lengths of 30- 140m, a steep (+75°) dip to the SW and thicknesses of 1- 10m, and NE-SW striking with a length of 120m, a steep (+75°) dip to the SE and thicknesses of 1- 5m.
- Lena: NE-SW striking with lengths up to 720m, a steep (+80°) dip to the West and thicknesses of 1- 15m.
- Leviticus: N-S striking with a length of 160m, a steep (+70°) dip to the East and thicknesses of 2- 8m. –
- Numbers: N-S striking with lengths of 140- 300m, a steep (+75°) dip to the East and thicknesses of 2- 10m.
- Big Sky: N-S striking with lengths of 100- 590m, a steep (+80°) dip to the East and thicknesses of 1- 5m.
- Waratah: NE-SW striking with lengths of 75- 380m, a steep (+80°) dip to the West and thicknesses of 2- 5m.
- Amarillo: N-S striking with lengths of 100- 460m, a moderate (+65°) dip to the East and thicknesses of 1- 10m.