This report presents exploration well data and interpretations relevant for mapping the variation in the depth to the base of ice-bearing permafrost (IBPF) for the Beaufort-Mackenzie Basin. This work is part of a larger government-industry funded petroleum systems study of the Beaufort-Mackenzie region that was active from 2001-2013. Geophysical well logs, well seismic surveys, shallow repeated temperature surveys, and deeper borehole temperature-depth profiles are utilized to determine the base of IBPF for 265 wells in the basin. Composite plots of log, seismic velocity and shallow temperature data illustrate typical geophysical responses and provide multi-parameter evidence for integrated interpretations of the IBPF zone. IBPF determinations are quality-assessed in terms of their reliability using a standardised scale based on the type of methods used and the quality of data available. For many of the wells, a sharp change in electrical and acoustic properties marks the base of the interpreted fully frozen IBPF zone which may represent the base of ice-bonded permafrost. For 135 wells, there is an underlying transition zone between 7 m to 210 m in thickness that is interpreted to represent partially-frozen IBPF. The interpreted co-existence of water and ice may be the result of changes in lithology, grain size, texture and/or pore water salinity which can affect the freezing point. There is a good correlation between the geophysically-determined base of IBPF and the depth to the base of permafrost from temperature surveys. This suggests that the mapped IBPF zone is a useful thermal boundary condition for thermal modelling and heat flow studies. For most of the wells, IBPF is confined to sandstones and conglomerates within Cenozoic sediments of the post-rift succession. Beneath the Beaufort Shelf, base of IBPF occurs within highly porous sediments of the Plio-Pleistocene Iperk Sequence. For central onshore areas (Richards Island and areas to south), base of IBPF occurs in progressively older, more deeply exhumed Cenozoic strata in a southward direction. Along the southeastern basin margin on Tuktoyaktuk Peninsula, IBPF extends into the Paleocene-Eocene Aklak Sequence. In the southernmost part of the basin and in the fold belt to the west, IBPF is encountered in Lower Cretaceous syn-rift and Upper Cretaceous post-rift strata. Permafrost occurs in exhumed Paleozoic strata in the Anderson Plain southwest of Tuktoyaktuk Peninsula. Depth to the base of IBPF varies from 0 m (no IBPF) to > 700 m across the study area. It is thinnest along the southern (landward) basin margin and in the deformed and exhumed western part of the basin, and is thickest in the rapidly deposited Cenozoic strata of the eastern shelf beneath the Beaufort Sea. IBPF may be absent over much of the modern delta area around Mackenzie Bay.

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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.

Baffin Fan is a 12 km-thick sedimentary wedge of Eocene to Pleistocene age in northwestern Baffin Bay, with size and resource potential comparable to Beaufort–Mackenzie Basin. A widespread Moho detachment originating in Mesoproterozoic strata may have influenced development of Cretaceous–Palaeogene horst blocks and half-grabens throughout the region, and their transformation by later phases of inversion. Reflection profiles indicate 12 depositional sequences in lower Palaeozoic and Cretaceous to Pleistocene strata. Notable is syntectonic sedimentation with possible volcanism and rifting in the Cretaceous–Danian. Sequences associated with inversion in the later Paleocene and Eocene display out-of-graben thrust anticlines formed over horst blocks in Lady Ann and Lancaster Sound basins. The Oligocene to mid-Miocene is associated with fluvial–deltaic systems, replaced since then by glacial–interglacial sequences including submarine canyons and deepwater fans. Exploration targets are located in Lancaster Sound, and a Baffin Bay fairway that runs 220 km northwestward to east of Coburg Island. Sixty-five per cent of prospects are located under Neogene cover. Fourteen are each greater than 70 km2, and five are between 334 and 592 km2. Based on drilling success rates elsewhere and the existence of a petroleum system, 12 of the 40 mapped structures may contain hydrocarbons in significant quantity.

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