ABSTRACT

Until 1969, only three wells had been drilled in Canada's Arctic Islands, all within the bounds of the Paleozoic Franklinian miogeosyncline. Ordovician-Silurian strata in the Lobitos et al Resolute L-41 well exhibit the carbonate facies of the Allen Bay Formation whereas in the Dome et al Winter Harbour #1 and the Dominion Explorers et al Caledonian River J-34 wells, the argillaceous beds of the (?) Ibbett Bay and Cape Phillips Formations were penetrated.

The Dome et al Winter Harbour #1 well encountered approximately 2,000 ft of calcareous shale, argillaceous limestone and chert of the (?) Ibbett Bay Formation. Core recovered from the interval 9790 to 9811 ft comprise finely laminated, calcareous shales and limestones, silicified to a minor extent, and showing nodular growth, compaction, early cementation (or calcification) and stylolitization. The nodular growth within the calcareous shale is demonstrated by the continuity of the sedimentary laminations through both rock types. The nodules are formed of micritic limestone with an occasional rind of silica and show horizontal bedding extending across the nodules. This bedding can be seen to extend into the adjacent shales surrounding the nodules but abrupt thinning appears to indicate compaction. The shales above and below are compacted and bend around the nodule. The compaction appears to be in the order of 50 to 60 per cent. Other portions of the core show compaction not related to the growth of nodules but due instead to a lateral variation in the percentage of CaCO₃. Those portions of the core not showing compaction have a greater percentage of CaCO₃, indicating that they were cemented or calcified sufficiently early that compaction could be resisted. Stylolites are of the sutured type, and for the most part, are vertically oriented. The thin laminations in the argillaceous limestone often have a distinctive pattern which suggests movement along the stylolite. This movement indicates that material has been removed along the stylolitic seam and is a post-compaction and lithification phenomenon, likely associated with the tectonic folding of the region.