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Ahbau Creek Targets

The Ahbau Creek area has two well developed targets each with a substantial work history for which there is much excellent unpublished data. The property has two known mineral occurrences about 1 km apart, the Ahbau Gold Zone and Ahbau PGE Occurrence (Figure 8). The writer spent no time on the Ahbau Creek showings and the following is based on Newell and Podolsky (1971), Freeze et al (1985), Kowalchuk and Mathison (1987) and Newton (1988).

Data for the diagrams presented here are taken directly from these and other authorities. The data have been replotted and georegistered; the data were scrutinized by the writer and they are considered accurate. Registration accuracy varies depending on the amount of information given in the sources. Assay results and drill intersections reported here are taken as presented in these sources.

Satellite image of Ahbau Creek area.
This satellite image of the area of interest at Ahbau Creek shows the two targets; the railway bridge across Ahbau Creek and the highway southwest of the creek are visible southwest of the targets. The yellow circle, labeled "Discovery Zone", represents the gold target. The other yellow circle, about 1 km south in the valley of Ahbau Creek gives the location of the PGE target.

Ahbau Gold Zone

The Ahbau Gold Zone is known since the 1950's and explored from the 1960's. Gold bearing sulphide veins are the target of interest. Mineralization consists of fault, fracture and shear zone controlled quartz-calcite veins and breccia zones. Veins locally contain 70 % sulphides, principally pyrite, pyrrhotite, sphalerite, galena and chalcopyrite in 30 % gangue of quartz and calcite. Faults and fractures commonly trend north and northwest. North trending structures dip moderately to steeply west and northwest trending faults tend to dip steeply. Gold values show little relationship to the proportion of sulphides. The Discovery Zone trends northeast and dips northwest moderately (Newton, D., 1988).

The Ahbau Gold Zone has a published "drill indicated" potential of 45,355 tonnes grading 10.2 g/t gold (Newton 1988). Surface grades of up to 7.6 g/t gold over 4.6 meters have been sampled. (Minfile Capsule Geology 093G-007).

Texas Gulf Sulphur acquired the property in 1971 and completed geological mapping, magnetic and electromagnetic surveys, and a large soil geochemistry survey. Equatorial Resources drilled 5 percussion holes totaling 1,530 feet in 1972.

Significant work completed in the Ahbau showing area since then includes extensive trenching in conjunction with two diamond drill programs by Gabriel Resources. In 1986 some 25 holes were drilled for a total of 1896 metres; the deepest hole was 142 metres. A second program in early 1987 completed a further 21 holes for 2809 metres; the deepest was 200 m. These programs aimed to test massive sulphide bearing fault zones. One fault zone, previously exposed by trenching, was roughly delineated by a fence of diamond-drill holes. Two other north-south trending, mineralized shear zones were also intersected by several drill holes. Some 100 backhoe trenches were completed (Kowalchuk and Mathison, 1987).

Late in 1987 Gabriel drilled 75 percussion holes for a total 6210 metres; the aim was to further test targets. The deepest percussion hole bottomed at 94.5 m deep in 4.6 m of 0.22 oz/ton Au (Newton, D., 1988). In this drilling the best gold concentrations were found along northwest trending structures, particularly the BL fault and intersections of shear zones appear to be most productive.

A 1991 drill program testing the syngenetic deposit potential of the property intersected subeconomic gold (3.86 g/t Au, >1% Cu)/1.5 m (drill width), copper, zinc, lead and silver mineralization, in veins, and disseminated zones in altered and mineralized volcanics and felsic intrusives (Gonzales, 1991).

Geological map of Ahbau Creek area.
The geological map of the Ahbau Creek targets shows the granodiorite of the Naver Plutonic suite in pink. The granodiorite is a fresh, medium grained, equigranular to porphyritic, biotite granodiorite to quartz monzonite of Cretaceous age. The pink area at the north of the map is the southern part of the Naver Pluton, the smaller areas in Ahbau Creek are outliers. Volcaniclastic rocks of the Nicola Group, locally hornfelsed and baked over the intrusive rocks, are intruded by the Naver. Faults that control the distribution of mineralization are shown. Diamond drill hole locations with some hole numbers are taken from Kowalchuk, J.M. and Mathison, D.A. (1987).

Major geophysical, geochemical, geological, trenching and drilling exploration programs completed in 1986 and 1987 returned subeconomic gold and copper values in trench, percussion chips and drill core of up to 41.8 g/t Au over 1.0 meter (drill width) Kowalchuk and Mathison (1987 - Part 1 of 2).

Maps of the Discovery area at Ahbau Creek. (See caption below)

Maps of the Discovery area at Ahbau Creek. (Above two images)
Some drill results on the Ahbau Gold zone are shown as are the copper soil geochemical results, based on work done in 1970 by Texas Gulf Sulphur. These are replotted and shown as the contoured surface overlain on the topography. Below is a detail to show the assay results on the faults. The UTM grid above is at 1km, below at 100m.

A 1988 summary states that several gold anomalies (mostly occurring in Ahbau Creek downstream of the Ahbau Gold occurrence) are present in stream sediments samples taken around the Ahbau Block in 1987.

A 1991 drill program testing the syngenetic deposit potential of the property intersected subeconomic gold (3.86 g/t Au, >1% Cu)/1.5 m (drill width), copper, zinc, lead and silver mineralization, in veins, and disseminated zones in altered and mineralized volcanics and felsic intrusives (Gonzales, 1991).

Details of the recontoured TGS soil geochemical data. (See Caption Below)

Details of the recontoured TGS soil geochemical data (Above two images)
The north part of the grid is above, the south part below. Soil sample localities are shown as small circles spaced at 100 feet intervals along lines 400 feet apart. Red labels show anomalous copper results and black labels give the original grid northing and easting (in hundreds of feet). The contoured surface is georegistered and shown in respect to the other data in figure 10.

Ahbau Creek drill hole locations, TGS soil grid, and faults
on the total field and potassium maps from this summer's survey. The maps show that the Discovery Zone is on the north fringe of a strong magnetic high and coincides with an areally modest high potassium zone- a classic "airborne target".

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This page was created on Tue Sep 7, 2010 at 6:59:46 PM Pacific Time.