Geoscience Map 2011-03: Geology, Geochronology, Lithogeochemistry and Metamorphism of theMahatta Creek Area, Northern Vancouver Island (NTS 092L/05) 1:50000 scale

G.T. Nixon, J.L. Hammack, J.V. Hamilton, H. Jennings, J. P. Larocque, A.J. Orr, R.M. Friedman, D.A. Archibald, R.A. Creaser, M.J. Orchard, J.W. Haggart, H.W. Tipper, E.T. Tozer, F. Cordey and C.A. McRoberts

http://www.empr.gov.bc.ca/Mining/Geoscience/PublicationsCatalogue/Maps/GeoscienceMaps/Pages/2011-3.aspx

Geoscience Map 2011-3 (1:50 000-scale) is the third in a series of five new geological maps (Geoscience Maps 2011-1 to 2011-5) of northern Vancouver Island which together provide a revised Early Mesozoic stratigraphic framework and Mesozoic-Tertiary plutonic history for southern Wrangellia. Geoscience Map 2011-3 describes the geology, geochronology, lithogeochemistry and metamorphism of the Mahatta Creek area (NTS 092L/05). The map area is underlain by a folded and faulted sequence of Late Triassic to Middle Jurassic volcanic and sedimentary rocks of the Vancouver and Bonanza groups intruded by granitoids of the Early to Middle Jurassic Island Plutonic Suite. The deformed Triassic-Jurassic rocks are unconformably overlain by Cretaceous marine clastics and cut locally by Tertiary dikes. Of note stratigraphically is the radical change in thickness of the Late Triassic Quatsino limestone across the Mahatta Creek area from the west coast (~40 m thick) to the east (Neroutsos Inlet >900 m). A young Tertiary (Neogene) granodiorite, the Klaskish River Pluton, which is the founding member of the Late Miocene – Early Pliocene Klaskish Plutonic Suite, intrudes Late Triassic Karmutsen and Early Jurassic Bonanza (Le Mare Lake unit) volcanic rocks near the foot of the Brooks Peninsula. Recent exploration at the northern margin of this pluton has targeted a Cu-Mo porphyry system similar to mineralization at the former Island Copper mine hosted by a Middle Jurassic intrusion of the Island Plutonic Suite. Major northwesterly-trending faults with inferred vertical and/or stike-slip offsets occupy drift-filled valleys subparallel to the coast and appear to repeat Bonanza Group stratigraphy. One such fault system, the Le Mare Lake - Red Stripe Mountain faults, has demonstrably displaced stratigraphic units about 5 kilometres in a right-lateral sense. These structures are intersected by a set of steeply-dipping, northeasterly-trending, subparallel faults comprising the Brooks Peninsula Fault Zone, one of which (the Klaskish River Fault) cuts the Late Miocene Klaskish River Pluton. Regional metamorphism is generally characterized by very low-grade mineral assemblages (prehnite-pumpellyite to zeolite facies) except in the vicinity of faults and intrusive contacts where the rocks may reach upper greenschist to amphibolite grade, respectively.

Information Circular 2011-4: Coal in British Columbia

A. Johal, B. Northcote and D. Lefebure

http://www.empr.gov.bc.ca/Mining/Geoscience/PublicationsCatalogue/InformationCirculars/Pages/IC2011-4.aspx

Thisbrochure briefly describescoaldeposits in British Columbia,including theEast Kootenay, Peace River, and Vancouver Island Coalfields. It has a location map of selectedcoal deposits.

Coal contributes a very significant amount of revenue to the B.C. economy. The average annual value of coal production over the last 5 years has been just over $3 billion, which represents over half the total value of mineral production in the province during that period.


More than 90% of the coal produced in British Columbia is metallurgical coal. B.C.’s metallurgical coal products generally have the following favourable characterisitcs: medium-volatile bituminous; clean coal ash < 9.5% (air dried); low sulphur (0.4% to 0.6%); low coke oven pressure; high coke stability and coke strength after reaction; low to moderate base/acid ratios; and excellent blending characteristics.

 

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Most provincial geoscience data can be easily accessed over the internet in map format at:

http://www.mapplace.ca/ and through various thematic pages at www.empr.gov.bc.ca/Mining/Geoscience

Printed BC Geological Survey geoscience publications are available from Crown Publications Inc.

Tel: 250-387-6409 Fax: 250-387-1120

Email: crown@pinc.com Website: www.crownpub.bc.ca/

Questions or to update your contact info please contact the BC Geological Survey:

Email: Geological.Survey@gov.bc.ca Tel: 250-952-0372 Fax: 250-952-0381

BC Geological Survey

British Columbia Ministry of Energy and Mines

Mines and Mineral Resources Division

Release Notification 2011-13

November 3, 2011