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The US Appalachian Basin and the Arctic Norwegian and Russian Barents Sea shelf (BSS) areas are two strategic provinces for the energy industry. The Appalachian Basin is a well‐studied, mature, onshore basin, whereas the offshore BSS is still considered a frontier area. This study suggests that the Appalachian Basin may be an appropriate analogue for understanding the BSS and contribute to development of a tectonostratigraphic framework for the area. Although the Appalachian and BSS areas reflect different times and settings, both areas began as passive margins that were subsequently subjected to subduction and continent collision associated with the closure of an adjacent ocean basin. As a result, both areas exhibited multi‐phase subduction‐type orogenies, a rising hinterland that sourced sediments, and a foreland‐basin sedimentary system that periodically overflowed onto an adjacent intracratonic area of basins and platforms with underlying basement structures. Foreland‐basin sedimentary systems in the Mid‐to‐Late Palaeozoic Appalachian Basin are composed of unconformity‐bound cycles related to specific orogenic pulses called tectophases. Each tectophase gave rise to a distinct sequence of lithologies related to flexural events in the orogen. In this study, similar sequences are recognised in both BSS foreland‐basin and adjacent intracratonic sedimentary sequences that formed in response to the Late Palaeozoic–Mesozoic Uralian–Pai–Khoi–Novaya Zemlya Orogeny, suggesting that the processes generating the sequences are analogous to the tectophase cycles in the Appalachian Basin. Hence, this pioneering use of the Appalachian area and its succession as large‐scale tectonostratigraphic analogues for the BSS may further enhance understanding of Upper Palaeozoic to Middle Jurassic stratigraphy across the BSS.

This trip explores three different occurrences of a diamictite-bearing unit in the transition between Upper Devonian redbeds of the Hampshire Formation (alluvial and fluvial deposits) and Mississippian sandstones and mudstones of the Price/Pocono Formations (deltaic deposits). Palynology indicates that all the diamictites examined are in the LE and LN miospore biozones, and are therefore of Late Devonian, but not latest Devonian, age. Their occurrence in these biozones indicates correlation with the Cleveland Member of the Ohio Shale, Oswayo Member of the Price Formation, and Finzel tongue of the Rockwell Formation in the central Appalachian Basin and with a large dropstone (the Robinson boulder) in the Cleveland Member of the Ohio Shale in northeastern Kentucky. Although several lines of evidence already support a glaciogenic origin for the diamictites, the coeval occurrence of the dropstone in open-marine strata provides even more convincing evidence of a glacial origin. The diamictites are all coeval and occur as parts of a shallow-marine incursion that ended Hampshire/Catskill alluvial-plain accumulation in most areas; however, at least locally, alluvial redbed accumulation continued after diamictite deposition ended. The diamictites are parts of nearshore, marginal-marine strata that accumulated during the Cleveland-Oswayo-Finzel transgression, which is related to global eustasy and to foreland deformational loading during the late Acadian orogeny. Detrital zircon data from clasts in a diamictite at Stop 3 (Bismarck, West Virginia) indicate likely Inner Piedmont, Ordovician plutonic sources and suggest major Acadian uplift of Inner Piedmont sources during convergence of the exotic Carolina terrane with the New York and Virginia promontories. Hence, the Acadian orogeny not only generated high mountain source areas capable of supporting glaciation in a subtropical setting, but also through deformational foreland loading, abetted regional subsidence and the incursion of shallow seas that allowed mountain glaciers access to the open sea.

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