Geology of New Brunswick potash deposits

CIM Bulletin, Vol. 72, No. 802, 1979

PAULW. KINGSTON, Industrial Minerals Geologist, New Brunswick Dept. of Natural Resources, DONALD E. DICKIE, Formerly Potash Project Geologist, New Brunswick Dept. of Natural Resources, Currently Geologist, Domtar Inc., Paris, Ont.

In New Brunswick, during the 1970's, rocks of the Lower Carboniferous Windsor Group in the Moncton Basin of the Fun-dy Epieugeosyncline have been the target of intense exploration and drilling programs. Sylvinite ore was discovered in three structural basins of the Moncton Basin near Sussex through a drilling program sponsored jointly by the Federal Department of Regional Economic Expansion and the New Brunswick Department of Natural Resources.In 1973, exploration and development rights to the western end of the Moncton Basin were awarded to the Potash Company of America. One high-grade sylvinite unit, varying between 15 and 70 feet in true thickness, with a strike length in excess of 5 miles, is located near the stratigraphic top of the assymetric, semi-diapiric, locally overturned anticline. Late in 1975, exploration and development rights to the Marchbank Syncline were awarded to International Minerals and Chemical Corporation (Canada) Limited. To date, a stratigraphic evaporite sequence, forming the semi-diapiric core of the syncline, has been shown to contain one major high-grade sylvinite unit averaging 70 feet in true thickness over a strike length in excess of 2 miles.Both properties appear to have potential considerably in excess of that revealed by the exploratory drilling, and both, because of numerous mineralogical, structural and stratigraphic similarities, are thought to be depositionally contemporaneous. Both potash deposits lie within 50 miles of the Saint John all-weather deepwater port, thus affording easy access to eastern and mid-western U.S. markets.Further opportunities for potash exploration in New Brunswick are considered excellent, as there are large untested areas with favourable geology and known potassium water anomalies and negative gravity anomalies occurring in the Moncton and Cumberland basins, and in the Central Basin of New Brunswick.
Keywords: Geology, Potash, Industrial minerals, New Brusnwick, Windsor Group, Moncton Basin, Sylvinite, Dunsinane synclinoryum, Marchbank syncline