Geo-Note 2003-02

Geo-Note 2003-02

GEO 2003-02

Carbonate-Hosted Pb-Zn (MVT) in Northeastern Alberta - 2002 Core Program: A Contribution to the Carbonate-Hosted Pb-Zn (MVT) Targeted Geoscience Initiative

Author(s) Rice, R.J. Zerbe, T. Date 2003-12-01

For the 2002 MVT core program, 113 cores from Middle and Upper Devonian carbonates in the subsurface of northern Alberta were examined. Core was selected from a large area incorporating the Fort McMurray and Fort Vermilion-Harper Creek study areas. A short, faulted and brecciated, intersection was encountered in one well, but no thicker intervals displaying classic MVT features, such as collapse breccia with hydrothermal dolomite, were found. Small amounts of pyrite were common, almost entirely as small fracture fills, nodules and stratification parallel accumulations that often are associated with fossil detritus. No visible galena or sphalerite was encountered. Trace element analyses returned a maximum lead (Pb) concentration of 246 parts per million (ppm) from pyrite-bearing Keg River Formation dolostone at 780 m in well GPD Noel et al Jean D�Or (15-27-109-07W5). The best zinc (Zn) concentration of 75 ppm came from pyrite-bearing Waterways Formation limestone at 110 m in well Esso 90-12 Oslo OV (07-10-095-09W4). The only sulphide mineral associated with fault-controlled breccia is pyrite with contemporaneous coarse calcite occurring at 257 m in Jean Marie Member, Redknife Formation dolostone in well Calstan Senex 4-3-100-7 (04-03-100-07W5). This pyritiferous zone is not associated with anomalous Pb or Zn values, but is associated with concentrations of arsenic (As) up to 383.4 ppm, tellurium (Tl) up to 3.4 ppm and molybdenum (Mo) up to 56.8 ppm; the concentration of these elements is an order of magnitude greater than those in most surrounding tabulated data for other core samples.

Rice, R.J. and Zerbe, T. (2003): Carbonate-hosted Pb-Zn in northeastern Alberta - 2002 core program: a contribution to the carbonate-hosted Pb-Zn (MVT) targeted geoscience initiative; Alberta Energy and Utilities Board, EUB/AGS Geo-Note 2003-02, 131 p.