Basins and fold belts of Prince Patrick Island and adjacent area, Canadian Arctic Islands

Prince Patrick and Eglinton islands have a polar desert climate and a landscape of coastal plains and dissected plateaux with limited vegetation cover. Use of a properly damped surveyor's compass is possible, however, magnetic declination changes markedly over short distances and large temporal variations are present. Bedrock of the report area is divisible into four major successions. These include: 1) 14 to 18 km of Proterozoic(?) and/or older bedrock above the Mohorovicic Discontinuity; 2) 10 to 14 km of thermally overmature but variably tectonized ("Franklinian") strata that range from Vendian(?) at the base through Upper Devonian at the top; 3) less than 1 km grading to more than 7 km of thermally mature and immature, relatively undeformed Carboniferous through Lower Cretaceous strata of the Sverdrup Basin, including up to 2 km of Middle Jurassic through Upper Cretaceous strata preserved in four peripheral basins and numerous small grabens; and 4) 70 m to more than 600 m of unconsolidated Pliocene sand, gravel, and peat, and related seismically defined Neogene strata of the Arctic Continental Terrace Wedge. The Franklinian succession is further subdivided into siliciclastic rocks of the Devonian clastic wedge (up to 6000 m thick), subsurface Lower Devonian and older strata of the Prince Patrick Platform, and correlative seismically defined deep-water strata of Canrobert Trough. A thrust-fold belt imaged seismically in the northeast is continuous with folds known at the surface on northwestern Melville Island, and folded Devonian strata are everywhere separated from Carboniferous and younger rocks by a profound angular unconformity. Other lower Paleozoic folds extend under southwestern Prince Patrick Island. A Carboniferous rift system located under the Sverdrup Basin margin has developed on the eroded roots of the Paleozoic fold belt. The rift formed in the Early Carboniferous (Serpukhovian), expanded to the southwest during the later Carboniferous, and was partly inverted during the Early Permian. Mid-Permian through early Middle Jurassic was a time of passive subsidence and progressive basin expansion toward the southwest. During Sverdrup Basin subsidence, four intracratonic basins, separated by Devonian "basement" highs, developed to the southwest between Middle Jurassic and Late Cretaceous time. An array of northerly trending horsts and grabens also developed during this time, part of a rift system that provides a geological record of the early development of the Arctic Ocean basin. Potential exists for far-travelled hydrocarbons within the Permo-Carboniferous and Jurassic-Cretaceous rift systems and in stratigraphic traps on the margins of the Mesozoic basins. Subbituminous coal seams to 1.5 m occur in Lower Cretaceous strata, and deposits of manganese carbonate are widespread in Campanian sandstone of Eglinton Island.