APPALACHIAN-BASIN ANALOGS AS A TOOL FOR UNDERSTANDING THE GEOLOGY OF THE BARENTS SEA SHELF

The Arctic Barents Sea shelf (BSS) covers approximately 1.4 million km², including the Exclusive Economic Zones of Russia and Norway, consisting of several structural elements and platforms. The geologic knowledge of this area has advanced considerably in the last few decades due to hydrocarbon exploration, but the region is still considered a frontier area. The tectonostratigraphic evolution of the BSS is very complex and includes responses to the Timanian, Caledonian and Uralian orogenies and to the opening of the Atlantic. The Timanian and Caledonian orogenies generated what is considered to be the Barents Sea “basement,” whereas the Late Paleozoic to Jurassic Uralian orogeny reactivated many basement structures and generated the currently expressed foreland and intracratonic basins, some of which have prolific hydrocarbon systems. Tectonostratigraphic processes similar to those of the BSS have been recognized across the Appalachian Basin and adjacent intracratonic areas, also major hydrocarbon-producing areas, and may provide analogs for understanding the BSS. Thus, we suggest using the well-known Appalachian region, including its foreland and adjacent intracratonic basins, as analogs to the BSS, although the ages and circumstances differ. The Appalachian Precambrian basement and its many structural inhomogeneities are analogous to the Timanian and Caledonian basement of the BSS. The Appalachian foreland basin is a direct analog to the Late Paleozoic/Mesozoic foreland basin of the eastern BSS, whereas western Appalachian intracratonic areas are analogous to western parts of the BSS, comprising several structurally controlled intracratonic basins. Also, like the Appalachian foreland succession, the Barents Sea foreland succession exhibits several unconformity-bound stratigraphic sequences that are very similar to the tectonic cycles (tectophase sequences) from the Appalachian Basin. Similar to the Appalachian Basin, these cycles begin stratigraphically with organic-rich, source-prone, black shales and end with molasse-like wedges of clastic sediments that can serve as reservoirs. Collisional settings like the Appalachian and Barents Sea areas, which experienced similar large-scale processes, may be comparable; hence, one may provide new sources of information about the other.