Broken Hill Zn-Pb-Ag Project
Altius, via a strategic alliance with Proton Geoscience Ltd., holds a 100% interest in 2 Exploration licences and one Exploration licence application (347 km2) over an extensive area of largely untested prospective Broken Hill Group stratigraphy under cover in the western part of the Broken Hill district, which is host to the largest single sediment-hosted Zn-Pb-Ag deposit in the world. Limited drilling by previous operators in geologically similar areas nearby has encountered wide intersections of anomalous Zn mineralization.
Altius and Proton are seeking a partner to advance exploration to discovery via investment or earn-in / JV agreement, building on work conducted to date.
The Broken Hill deposit has been mined continuously since the late 1800’s, and the region continues to support three mining operations. The project area lies under cover to the west of the outcropping area of the Broken Hill block. Whilst there has been recent exploration, the large area under claim has only hosted a total of 18 drillholes which intersected basement. These drillholes have largely confirmed the presence of prospective Broken Hill Group rocks.
The main orebodies at Broken Hill are hosted in distinctive garnet-bearing quartzo-feldspathic gneisses of the Hores Gneiss, part of the Broken Hill Group. In the immediate deposit area, the meta-arkosic sediments are accompanied by amphibolite, felsic gneiss, minor units of BIF and quartz-garnet-gahnite lithologies. The deposit has a pronounced alteration halo that extends over at least 3 to 4 km along strike beyond the line of lode, and may be up to 500 m thick, defined by garnet spotting and increasing enrichment in K-Rb-Fe-Mn-Pb, and depletion of Na-Ca-Mg-Sr, towards mineralisation. From a geophysical point of view, the deposit occurs at the transition from an oxidized and highly magnetic underlying sequence, to a more reduced and less magnetic overlying sequence. The deposit occurs on the flank of a pronounced gravity high.
In the covered area near the Altius tenements, stratiform Zn-Pb-Ag mineralization has been intersected in a similar stratigraphic horizon at the Polygonum and Thunderdome prospects, where mineralization is hosted by fine-grained garnet-bearing to garnet-banded, interlayered psammitic to psammopelitic metasediments with some calcsilicate lenses and spatially associated banded iron formations. Drill results include: - 7.2m at 0.8% Pb, 14 g/t Ag and 0.2% Zn at Thunderdome (hole P2 Leyh and Conor 2000) - 103m @ 0.13% Pb and 0.14% Zn at Polygonum (hole P06 Main and Richards 1985)
The main project area shows clear evidence of the existence of extensive areas of prospective Broken Hill Group stratigraphy, and shows a number of empirical similarities to Broken Hill and related orebodies.
Prioritised for immediate exploration aimed at early discovery are:
EL8485: Reinterpretation of magnetics and gravity has allowed the identification of a likely synsedimentary growth fault which marks a transition from relatively thin Broken Hill Group to a relatively thick and polydeformed sequence in the main part of the tenement. Reprocessing of gravity data has allowed the recognition of a gravity ridge which crossed this structure, and may be related to underlying faults and/or lithological boundaries. The small amount of drilling in the area has confirmed the presence of Broken Hill group rocks, though the main target area has not yet been tested
ELA5429: Magnetic interpretation on this area has allowed the recognition of a structural inlier of Broken Hill Group within stratigraphically lower and more magnetic rocks. Within this package there are a number of strike-discontinuous magnetic anomalies which may represent the BIFs often encountered in association with Broken Hill lode rocks. The overall geological setting in this area is somewhat analogous to that seen at Cannington in Queensland, another BHT deposit.
EL8484: In this area, subcrops of Broken Hill group lie under shallow cover. Previous exploration has been strongly focused on geophysics, and there is potential to trial geochemical approaches which may identify systems not tested in previous programs.
Richard Valenta, P.Geo., Consulting Geologist is the qualified person as defined by NI 43-101 guidelines responsible for the technical data presented herein.