KAKWA RECREATION AREA: NORTHEASTERN BRITISH COLUMBIA GEOLOGY and RESOURCE POTENTIAL (93H/15, 16, 931/1, 2) by J
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KAKWA RECREATION AREA: NORTHEASTERN BRITISH COLUMBIA GEOLOGY AND RESOURCE POTENTIAL (93H/15, 16, 931/1, 2) By J. Pell, .J.L. Hammack, B. Fletcher and W.D. Harris Geological Consultants KEYWORDS: Regional geology, Kakwa Recreation Area, Parks and Willmore Wilderness .Area in Albert;, The .ire#IS resource assessment. stratigraphy. coal, dimension stone, quite remote and access is generally on lhmeb sk,011 bat, phosphate, lead-zinc barite, mineral potmtial. or by helicopter or float plane. .!,I old lorging road, ahg the McGregor River valley, leads to the s~then and west- ern edge of the recreation area ;lrd an extensi, n leads l,rllo INTRODUCIION the area: however, wash-outs along this road I ave mad? it The Kakwa Recre.rtion Area encompasses approximately impassable to vehicles. Trails suit~rble fordirt t ikes ald 2111- 128 000 hectare's ( 2x0 km') of wildernesh land imme- terrain vehicles lead into the nurtheaster~par of the mea diatelywest of the Albertaborder and approximately from Shelman Meadows, in Alberta. 70 kilometres north of the town of McBride, British Colum- Relief in Kakwa is considerab~.:.with clevat ons rmgir,g bia. at latitude S4"OI)' north,longitude 120"20' wcst (Fig- from less than 915 metres (3000 feet) ir the larvis Creek ure 1-6-1). It is thcnorthernmost parr of acontiguous, valley, alongthe western eclp,: of the ar :a, tc c','t:r northwest-trendirlg belt of parks and wilderness areas that 3050 metres (IO 000 feet) at Mourlt Ida (3190 n )and WOIIII~ includes Yoho N;ltion;rl Park and Mount Robson Provincial Sir Alexander (3275 m). Much of the terrain s ver) sleep Park in British Colwnbia. and Banff and Jasper National and cliffs are common. There arc: .arge icefield near Wollrt 66 wy Brunch Geolo~iculFieldw,vk 1991, Puper 1992-1 Ida. Mount Sir .4lexander and Mount Dimsdale and along In theIntersection Mountain area, rocks of the Miette the northwestern boundary of the recreation area. Group include a well-bedded, cliff-forming unit consisting There has been very little exploration work in Kakwa, in of medium orange-brown-weathering, dark grey, calcareous part due to itsremoteness. Thereare coal leases in the quartzite-granuleconglomerate and quartz wacke with northeastern part of the region and some oil and gas permits interbedded medium to dark grey phyllite. This unit is were also held there in the early 1980s. Quartzite, near the underlain by a thick, poorly exposed,dark grey phyllite. centre of the region, has been examined for its potential as a building stone. A lead-zinc-barite showing is located a few LOWERPALEOZOIC kilometres north of the recreation area and a gypsum pros- pect a short distance to the southeast. Although there has Lower Paleozoic strata underlie a significant proportion been limited activity, the geology indicates that a number of of Kakwa Recreation Area (Figure 1-6-2) and comprise a potentially economiccommodities could existwithin the conformablesequence thatdisconformably overlies Pro- boundaries of the recreation area, including coal, phosphate, terozoicrocks. TheLower Cambrian Cog Group, which gypsum,lead, zinc,barite and dimension stone. Kakwa formsthe base of this succession, consists of the RecreationArea is currentlyunder consideration for McNaughton. Mural and Mahto formations (Table 1-6-1). upgrade to Class "A" parkstatus and, prior to its The McNaughton Fonnation is a resistant,rusty to dark- reclassification. the mineral potential of the area must be weathering unit that forms a thick and fairly monotonous evaluated, which is the focus of this project. sequence dominated by medium to thick-bedded light grey quartzites.These quartzites areoften laminated or GEOLOGICAL SETTING crosslaminated: thinblack shalelayers and granule to pebble-conglomerate beds are present locally. In some areas Kakwa lies within the Foreland tectonostratigraphic divi- crosslaminationsare stainedpinkish, giving the rock an sion of the CanadianCordillera and is underlainby a attractive banded appearance. In the area south and west of sequence of carbonate and clastic sedimentary rocks rang- Wishaw Mountain, black siltstones and argillites are inter- ingfrom Late Precambrian to Early Cretaceous in age. bedded with the quartzitesand locally form units tens of Folds and southwest-dipping, northeasterly directed thrust metres thick thatcontain thin quartziteinterbeds. The faults are the dominant structuresin the region. Major thrust McNaughtonFormation is largelydevoid of fossils: sheets contain strata which generally young to the northeast. however, trace fossils such as worm tubes (Scolithus) and Previous work in the area includesregional mapping by meandering patterns on bedding planes, suggestive of worm Campbell, Mountjoy and Young (1973), McMechan (1986). trails, occur in the upper parts of the unit. In the Kakwa McMechanand Thompson (1985) andTaylor andStott area, the McNaughton Formation is estimated to be approx- (1979). imately 1500 metres thick (McMechan, 1990 Slind and Perkins,1966). STRATIGRAPHY The Mural Formation is a reddish brown. recessive unit UPPERPROTEROZOIC (HADRYNIAN) predominantlyconsisting of silty andsandy dolostones, dolomitic quartzites, shalesand minor limestone. Its contact Rocks of the Hadrynian Miette Group are exposed in the with the underlying McNaughton Formation is gradational hangingwall of the Mount St. George fault in the Moonias and consists of a zone of interbedded light grey quartzites, Mountain area; the Snake Indian and Wishaw faults near dolomitic quartzites and dolostones. The Mural Formation Intersection Mountain; andthe Mount Sir Alexander and begins wheredolomitic rocks dominate over quartzites. Wishaw faults south of Wishaw Mountain (Figure 1-6-2). Orange to tandolostones, dolomitic quartzites and grey Only theupper parts of thisunit are exposed withinthe quartzitescharacterize the lower part ofthe formation, study area and detailed observations were possible only in while grey and greenish grey shales, grey crystalline lime- the Moonias Mountainand Intersection Mountain areas. stones. dolostones and lesser amounts of quartzite are more AtMoonias Mountaintwo lithologicunits were common in the upper part. Dolomitic quartzite beds often observed.The lowestcomprises a relativelyresistant, grade up-section intosandy dolostones. Scolirhus worm thicklybedded, medium brown weathering quartzite- tubes are common in thesandy layers (Plate 1-6-1). This granule to pebble conglomerate, quartz wackeand medium formation is 225 to 300 metres thick in the Kakwa region. greyquartz arenite, interbedded with brownand grey- The Mahto Formation is a grey to maroon, resistant unit, weathering argillite andminor light grey quartzarenite. overlying the recessiveMural Formation. In the Kakwa area Minimum thickness for this unit is 300 metres. The con- it is approximately 300 to 350 metres thick. It consists of glomerate is composed of well-rounded quartzite pebbles light grey to creamy beige, pink and maroon, medium to supponed by amatrix of medium-grained, poorlysorted thick-bedded quartzites with minor amounts of interbedded quartz wacke. This lower unit is overlain by in excess of brown and dark grey sandy shales, dolomitic quartzites and 200 metres of thinly bedded, dark brown-grey argillite with siltstones. As with the other units of the Gog Group, fossils thinsilty interbeds. Siltybeds are locally crosslaminated are restricted to Soolithrrs worm tubes. Quartzites are gener- and show graded bedding. Onethick unit within the argillite allyfine to coarsegrained and, locally, granule- has abundant tat-weathering dolostone breccia blocks of conglomerate layers are present. Colours of the quanzites probableolistostromal origin. These blocks are up to 6 vary from solid greys, pinks and maroonsto very attractive, metres in diameter and stand out in relief against the more intricately swirled and banded patterns in shades of maroon, recessive argillite. pink and creamy white (Plate 1-6-2). 68 Brirish Columbia GeoloRicul Survey Branch TABLE 1-6-1 TABLE OF FORMATIONS LOWER CRETACEOUS Gates Fm: 12-1 10 m) sandstone. carbonaceous shale, coal (Middle and Torrens River members, in descending order) Moosebar hn: (550mi shale, minor sandstone BULLHEAD GROUP Gething Fm: (25-UO m! sandstone. sillstone. coal Cadomin Fm (t25 m) conglomerate ~- unconhrntity __ MlNNES GROUP Gorman Creek Fm: 1650-1000 m! sandstone. siltstone. minor cwal UI'PER JURASSIC AND LOWER CRETACEOUS Monteith Fm 1200-400 m) sandstone, dtslone. shale JL RASSIC Fernie Fm: (250~900m) shale. silly sandstone, siltstone -_ unconfonnity __ -.~ TIIIASSIC SPRAY RIVER GROUP Whitehorse Fm: l130~400m) dolustone. limestone, evaporites (Winnifred. Brewster and Starlight evaporite members. in descending order) Sulphur Mountain Fm: (405~475mi dtstone, silty limeslone (Llama. Whlstler and Vega-Phrusu memhen. in descending order) PERMIAN Mowich Fm: It IO m) sandstone, conglomerate at base Belcoun Fm: (>IO m) limestone, conglomerate at base UPI'ER CARBONIFFROUS Haninglnn l'm: (0-5 m) limestone wibasal pebble conglomerate - unconfonnity ~ -.__. L'IWER CARBONIFEROUS RUNDLE GROUP 12400 m) limestone, dlrloslone (Mt. Head. Turner Valley. Shunda & Prkisko formations. in descending order) UPPER DEVONIAN AND LOWER CARBONIFEROUS Exrhaw & Ran11 fmr: IIHOL2M) m) rhale, minor limestone ~~ ""c""f0rmity UPPER DEVONIAN Palliser Fm: I1530 m) limestone Ifossil-poor1 . Flume Fm: 175-145 m) limestone, slromalopomid biostrome - unconfmniry __ MIDDLE DEVONIAN Dunedin Pm*: (160 m) limcstonc, svltwme. conglomerate " unconf<,mity __ MIDDLE ORDOVICIAN Unnamed