The BGGB is dominated by an E-NE trending, isoclinally folded sequence of mafic to felsic metavolcanics and overlying metasedimentary rocks. These rocks are cut by a series of felsic to intermediate dykes and plutons. Lower Proterozoic diabase dykes crosscut all of the above units and felsic intrusives and are interpreted to postdate mineralization.
In detail, the OTGB consists of felsic to mafic metavolcanic (calc‐alkaline and tholeiitic) sequences bound to the south by the BGB’s northern contact defined by the Paint Lake Deformation Zone. Metavolcanic rocks of the OTGB are deformed into arcuate shaped belts related to the emplacement of ovoid granitoid intrusions.
Regional structures and stratigraphy exhibit N-NE trends while late NW-SE trending fragile structures are common in the southern part of the OTGB. The mafic metavolcanic rocks are interbedded with felsic pyroclastic rocks and quartz-feldspar porphyries with rhyolite flows. The mafic meta-volcanic rocks consist of massive to foliated, pillowed, porphyritic and amygdaloidal flows and chlorite schists, tuffs and agglomerates. The felsic metavolcanics consist of rhyolitic to rhyodacitic flows, rhyolite porphyry, crystal tuff, lapilli‐tuff, tuff breccia, rhyolitic quartz feldspar porphyry and pyroclastic breccia.
Two main structural trends exist at LAURION’s Ishkoday property.
These are northeast-southwest trending quartz-sulphide and polymetallic veins, and east-west to east-southeast trending faults. Most of LAURION’s Ishkoday veins are oriented northeast-southwest, and represent a dilatant crack-seal type veining with minor associated shearing. Dextral movements along the east to southeast trending faults are thought to represent the mechanism which produced the northeast dilatant features hosting the gold-bearing quartz veins.
Gold is associated with quartz(-carbonate) veins hosted by felsic to intermediate meta-volcanics, and located often marginal to felsic intrusions (either dykes, stocks or plutons). Veins are typically sigmoidal or lenticular and free visible gold is common. Sulphide content within such veins ranges from trace to 40%. Coarse pyrite, pyrrhotite, chalcopyrite, sphalerite and galena may be present in the veins. Gold usually occurs as either in quartz veins as free coarse gold or in fractured sulphides. Gold can also occur in sheared chlorite and sulphide rich wall rocks.
AS part on the 2018 exploration work, and interpreted presence of a new structural corridor incorporating the main 3km x 1km Target Area at Ishkoday: the 6km wide gold bearing Ishkoday Deformation Zone (“IDZ”). The IDZ is a new shear/deformation zone, an apparent new splay off the Paint Lake Shear/Deformation Zone (the “PLDZ”). The new Break is similar to the PLDZ, and to other gold bearing deformation zones such as in the Abitibi Greenstone Belt: the Destor Porcupine (“DPDZ”) and Cadillac Larder Lake Deformation Zone (“CLLDZ”), which host major gold deposits.
The Ishkoday occurs on the southernmost “Breaks”, the “Sturgeon River Break”, where there are at least two additional subsidiary shear/deformation zones (the “Sturgeon River North and South Breaks”) giving an overall 6 km width to the combined IDZ. The proximity of the PLDZ to the IDZ suggest a splitting of the former into multiple east-west to northeast-southwest shears at Ishkoday. The presence of multiple shears and movement within the Break would significantly fracture the brittle felsic volcanic package at Ishkoday, allowing for the development of the observed quartz veins with gold-sulphides
This major kilometric long and wide NE-SW structural corridor encompasses most of the known precious and base metal mineralization at Ishkoday of the main 3km by 1km Target Area. Mineralization is open along strike to the E-NE and W-SW and is open at depth down-plunge beyond 650m as indicated from the historic Sturgeon River Mine development and production – a very significant gold target.