Hale River EL 2046 annual report for period ending 24 September 1980

Abstract

On the assessment of the 1978 drilling programme, further work on detailed mapping 1:l000 and a ground spectrometer survey were completed to assess the southern extension of the Albarta Fault System. The availability of drilling rigs has been low, however the proposed drilling programme is expected to begin early October when a T685 Schramm rotary percussion drill becomes available. A ground spectrometer survey using Geometrics 410 spectrometer over a grid 1.3 km x .6 km was completed for U3O8, Thorium, Potassium and Total Count. U308 values are contoured and U308, Th, K, and Total Counts are presented in raw data form only. Anomalous areas coincide with outcrop and in general are not encouraging. Alluvium and scree inhibit better use of ground radiometric survey. The survey extended from Lower Proterozoic rocks east to the Heavitree Quartzite.

The area covered by the spectrometer survey was also mapped on 1:1000 in an attempt to gain some understanding of the geology in the southern region. Alluvium cover is extensive and most outcrop was found in creek banks. The amphibolites in this area are often highly migmatised with quartz-feldspar melts being formed with pegmatites in extreme situations. Tourmalinisation of leuco-gneiss is present in rare situations. Chloritisation of amphibolites and leucogneisses together with migmatisation which appears to be in shears and minor hinge zones often obliterates the original textures completely.

Two occurrences of Cu mineralisation were found. At the northern end weak Cu-U mineralisation is present in an old pre-Albarta fault consisting of quartz-haematite sericite rock, just west of the Heavitree Quartzite. Malachite was also found as a thin discontinuous film coating fractures over a ten metre interval ,in chloritized amphibolite and quartz-haematite-feldspar breccia outcropping in a creek bank west of the bore. Radioactivity was low. An attempt was made to obtain a versatile foxmobile type of drill rig capable of both precollar percussion and subsequent core drilling. No such rig was available and consequently Northbridge were contacted and indicated that a large capacity Schramm would be available at considerable mobilisation costs. Unfortunately this offer was later withdrawn by them due to logistical and work load problems encountered by Northbridge. Rockdrill have indicated a firm latest starting date to be 6th October, 1980. Consequently a drilling programme incorporating a T685 Schrarru rotary percussion rig has been approved for the Albarta Prospect. Ore hundred hours of work by a D7 Caterpillar bulldozer were involved in preparation of access and sites. This area has extremely rugged geomorphological features due to a combination of its arid climate and rock types dominated by sharp escarpments consisting of Heavitree Quartzite. The drilling programme of 1978 confirmed that the westerly dipping Albarta fault zone consists of mainly quartz and silicified country rock with massive chlorite haematite and 1-5% pyrite. The majority of the radio- metric activity is associated with the pyritic chlorite schists and the K?feldspar chlorite schists to the west of the fault, with the fault zone usually being radio- metrically inactive. A fence of three -60 angle holes are designed to test the potential of the muscovite and chlorite schists west of the Albarta fault. This fence covers a total count spectrometer high. Two holes are designed to test the Albarta Fault in areas where it is truncating older structures and being truncated by younger structures. Three holes are planned to test the Unconformity Type

Model where the Heavitree Quartzite is overlying Lower Proterozoic rocks which are hosting a major tectonic structure. A total of eight holes up to 150 m each are planned for the programme with five sites available for further evaluation.