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File Created: 24-Jul-85 by BC Geological Survey (BCGS)
Last Edit:  01-Mar-11 by Sarah Meredith-Jones(SMJ)

Summary Help Help

NMI
Name ANN NORTH, OPHIR, PEACH, LAC LA HACHE Mining Division Clinton
BCGS Map 092P094
Status Prospect NTS Map 092P14W
Latitude 51º 58' 27" N UTM 10 (NAD 83)
Longitude 121º 18' 46" W Northing 5759509
Easting 615891
Commodities Copper, Gold, Molybdenum Deposit Types L03 : Alkalic porphyry Cu-Au
Tectonic Belt Intermontane Terrane Quesnel
Capsule Geology

The Ann North copper showing is located 1 kilometre south of Peach Lake approximately 22 kilometres northeast of Lac La Hache and is readily accessible from Highway 97 via a network of logging roads. Other names for the claims and showings have been the Peach and the Ophir. The Ann North showing is one of several copper showings on the current (as of February 2003) Ann 1 and 2 claims (see also 092P 001, 034, 035, 115 and 153). All of these occurences are part of the Spout Lake copper-gold district, a group of porphyry and skarn deposits associated with Upper Triassic to Lower Jurassic alkaline intrusive rocks of the Spout Lake intrusive suite.

The Ann 1 and 2 claims are underlain by andesites, basalts, calcareous tuffs and argillites of the Upper Triassic Nicola Group (Assessment Report 25368). Nicola Group rocks are intruded by the Upper Triassic to Lower Jurassic Spout Lake Intrusive complex, an alkalic intrusive suite ranging in composition from pyroxenite through monzonite to syenite, and from batholithic size to small intrusive plugs, dikes and breccia bodies. Granodioritic rocks of the Triassic to Jurassic Takomkane Batholith intrude Nicola rocks east of the property. Outliers of alkaline plateau basalts of the Miocene to Pleistocene Chilcotin Group are present in the general area.

Copper-gold mineralization is generally associated with zones of strong potassic and propylitic alteration of intrusive rocks (diorite, monzodiorite and syenite). It is also locally present within Nicola Group volcanic rocks adjacent to these intrusions. Sulphide mineralization occurs within veins and along fracture planes commonly containing epidote, chlorite, quartz, K-feldspar, magnetite and variable amounts of calcite, biotite and albite. Sulphides also occur as fine to medium-grained disseminations and mafic replacements in areas of strong fracturing and intense alteration. The most common sulphide minerals are pyrite (16% average) and chalcopyrite (<0.1-l% average) with trace amounts of bornite, molybdenite, pyrrhotite and tetrahedrite occurring locally. Gold values generally correspond with strong pyrite-chalcopyrite mineralization and subsequent high copper values. Common secondary minerals related to supergene alteration are limonite, malachite and to a lesser degree azurite, chalcocite and native copper.

George Cross Newsletter #134 (2000) states that mineralisation in the Ann North zone is comprised of predominantly chalcopyrite, bornite and less than 0.3% pyrite, and is hosted by a k-feldspar porphyritic monzonite intrusion which intrudes monzonite. Native copper and chalcocite occur to a depth of about 50 metres. Quartz-magnetite-hematite and k-feldspar alteration are associated with the mineralisation. The showing is reflected as a magnetic and induced polarization depression or "low" about 1.0 by 0.8 kilometres in size. A drill hole intersected 44.0 metres of mineralization grading 0.31 per cent copper and 0.43 grams per tonne gold (G.W.R. Resources Incorporated report, March 2001).

Interest in the Spout Lake area was triggered in 1966 when the Geological Survey of Canada released the results of a regional airborn magnetic survey which outlined an annular magnetic anomaly 10 kilometres in diameter in the Spout Lake area and which included the area underlying the Peach 1 prospect. Subsequently in 1966 and 1967, Coranex Limited abtained anomalous results in follow-up stream sediment geochemical surveys and soil geochemical surveys in the area south of Peach Lake. Programs of geological, soil geochemical, magnetometer, induced polarization and prospecting surveys were undertaken in 1967 in the area south of Peach Lake, leading to the discovery of the Peach 1 and several other occurences. Asarco Exploration Company of Canada Limited optioned the property in 1969. Amax Potash Limited optioned the property between 1971 and 1973 and completed programs of geological mapping, geophysics and percussion drilling. In 1983 and 1984, the Selco Division of BP Resources Canada Limited completed soil geochemical surveys on the Core group of claims which covered the property. G.W.R. Resources Incorporated acquired the property in 1988 and Asarco re-optioned the property and completed induced polarization surveys and percussion drilling in 1991. In 1993, G.W.R. Resources formed a joint venture with Regional Resources and have since completed programs of induced polarisation and diamond drilling. G.W.R. Resources has completed additional diamond drill programs in 1998, 1999, 2000, 2002 and 2003.

In 1998. GWR Resources Inc. carried-out a diamond drill program (4 holes) in the northeast section of the ANN 2 claim to test the copper-gold mineralization potential of a moderate to strong IP anomaly (Zone 3, 1991). Three of the four holes encountered zones (10 to 30 metres) of low grade copper-gold grading between 0.1 - 0.2 % Cu and 0.1 - 0.2 g/t Au, with a few shorter sections (3 to 6 meters) grading up to 1.12% Cu and 1.32 g/t Au (Assessment Report 25861)

In 1999 and 2000, GWR Resources Inc. again conducted diamond drill programs in the central and northeast sections of the ANN 2 claim. Four holes were drilled in 1999 and 25 holes were drilled in 2000. Results were encouraging with anomalous copper-gold intersections variously encountered in about 50% of the holes.

In 2002 and early 2003, GWR Resources Inc. carried out further diamond drilling in the northern half of the ANN 2 claim. Nine holes were drilled in 2002 and three holes (one on the adjacent DORA 2 claim) were drilled in 2003. Results again were encouraging with anomalous copper-gold intersections variously encountered in about 60% of the holes.

In March 2003, GWR Resources Inc. initiated a diamond drilling program to test a large magnetic anomaly located in the northeast section of their 100 per cent owned ANN 2 claim. Seven NQ angle holes totaling 977.14 meters) were drilled as part of a program to test a magnetic anomaly. The anomaly (designated the Northeast-mag Zone) occurs about 500 meters north of the Harvey Zone where anomalous copper-gold mineralization was intersected in diamond drillholes drilled by GWR Resources Inc. in 2002.

In 2004, the Ann North porphyry copper-gold property, was the subject of several waves of drilling and trenching by GWR. Positive results were reported from several drillholes (roughly 3000 metres total) in a strongly potassic-altered quartz monzonite intrusion. The best hole was 04-19 which cut 26 metres grading 0.50 per cent copper and 1.23 grams per tonne gold at shallow depths, and 107.3 metres grading 0.29 per cent copper and 0.33 grams per tonne gold deeper down in the hole (Exploration and Mining in BC 2004, page 58).

Bibliography
EMPR AR 1966-126, 1967-126, *1968-155
EMPR EXPL 2002-47; 2003-55; 2004-58
EMPR GEM 1969-183, 1972-324, 1973-278
EMPR MER 2003-10; 2004-10
EMPR PF (*Lac la Hache Project, G.W.R. Resources Inc., March 2001)
GSC MAP 1966-3, 1278A
GSC MEM 363
GCNL #134 (Jul.13), 2000
PR REL GWR Resources Inc., Mar.18, 2003
Stockwatch 2003-03-19
Whiteaker, Robin (1966), The Geology, Geochronology and Mineraliation of the Ann Property: and Early Jurassic Alkalic Porphyry system near Lac La Hache, B.C. Honours B.Sc. Thesis, U.B.C.

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