The Hemm property is approximately 25 kilometres northeast of Port Renfrew and adjacent to Reko occurrences (092C 090, 110). Reako Explorations Ltd., searching for iron-magnetite deposits in the 1970's, did the initial work in the area. Little work was done until the 1990's when Cowichan Terrazo and Ceramic Tile (CTCT) cut several blocks from the southern unit but results of their work is not publicly available. Access is by logging roads northeast from Port Renfrew to the headwaters of Renfrew Creek. The HEMM claims were staked in 1999 to cover exposures of limestone. Initial work on the HEMM was in an attempt to identify a location for limestone dimension stone. That examination discovered a complex geology unsuitable for stone and the focus shifted to evaluation for limestone as an aggregate or chemical source material.
The oldest rocks in the area are the Paleozoic Wark Diorite/gneiss and Colquitz Gneiss complexes. Overlying those is the Triassic Vancouver Group, comprised from bottom to top, the Karmutsen, Quatsino and Parson Bay formations. The Karmutsen Formation comprises Basaltic pillow lava, billow breccia and flows with minor interbedded limestone. The Quatsino Formation comprises a thick succession of massive to bedded limestone. The Parson Bay Formation is comprised of interbedded calcareous sediments and limestone. Overlying this package is the Jurassic Bonanza Group. This group is a complex package comprised of interbedded lava flows, breccia and tuff that varies in composition from basalt through rhyolite. Intruded through these groups are intermediate to acidic plutons and dykes of the Jurassic Island Intrusions.
The property is underlain by grey to white crystalline limestone, and by intrusive breccia. This andesitic rock was successively intruded by mafic-rich and mafic-poor diorite. The breccia grades from massive diorite in the south to massive andesite in the north. Sets of long, narrow, fine-grained grey dykes strike 020 degrees and transect all other rocks. Dykes of andesite and leuco-diorite have successively intruded most limestone bodies.
The Quatsino Formation limestone is the primary focus of exploration at the HEMM property. The limestone is typically fine-grained, blue-grey in colour and weathers dark grey to black. Two units of limestone transect the property roughly east to west. Bedding was measured ranging in strike from 124 to 160 degrees and in dip from 20 to 70 degrees. Mapping determined the limestone present is white to grey-white with some interbeds of black and light green. The limestone is partially recrystallized to marble with grain sizes of 2 to 5 millimetres. The limestone is generally quite clean with only a few clay layers, limonite or sulphides. Fracturing generates blocks 1 to 6 metres across suggesting potential for rip-rap material. The colour also suggests potential as an industrial filler material.
Volcanic rocks present are fine grained (flows?), basaltic to andesitic in composition and lie conformably with the limestone. Intrusions of granite are present at the northwest part of the property.
In 1999 and 2000, Mammoth Geological Ltd. completed programs of geological mapping on prospecting and the area as the Hemm 1-4 claims. In 2002, Southern Pacific Development completed a program of geological mapping and geochemical sampling of the limestone. Analysis of the limestone has shown iron oxide and silica impurity contents at the upper ranges of those acceptable for ground calcium carbonate (GCC) products. Brightness analysis indicates levels around 86.1 per cent, which is less than the 95 per cent requirement for filler grade limestone. The rock was not tested (@ 2001) for porosity or compressive strength related to aggregate and rip-rap applications (Assessment Report 27081).
