The Mezen Basin is a
sedimentary basin
Sedimentary basins are region-scale depressions of the Earth's crust where subsidence has occurred and a thick sequence of sediments have accumulated to form a large three-dimensional body of sedimentary rock. They form when long-term subsidence ...
located in northwestern
Russia
Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eigh ...
. It list southeast of the
White Sea
The White Sea (russian: Белое море, ''Béloye móre''; Karelian and fi, Vienanmeri, lit. Dvina Sea; yrk, Сэрако ямʼ, ''Serako yam'') is a southern inlet of the Barents Sea located on the northwest coast of Russia. It is s ...
and bounds the
Timanide Orogen
The Timanide Orogen (russian: Ороген Протоуралид-Тиманид, literally: "Protouralian–Timanide Orogen") is a pre-Uralian orogen that formed in northeastern Baltica during the Neoproterozoic in the Timanide orogeny. The orog ...
to the north and west.
The basin is classified as a pericratonic and epicratonic foreland basin
A foreland basin is a structural basin that develops adjacent and parallel to a mountain belt. Foreland basins form because the immense mass created by crustal thickening associated with the evolution of a mountain belt causes the lithosphere ...
within the East European Craton
The East European Craton (EEC) is the core of the Baltica proto- plate and consists of three crustal regions/segments: Fennoscandia to the northwest, Volgo-Uralia to the east, and Sarmatia to the south. Fennoscandia includes the Baltic Shield ...
. The Mezen Basin contains the following pre-Vendian sediments: the Ust-Nafta Group with a maximum thickness of 1200 meters, on top of this is rests the Safonovo Group made up of carbonate
A carbonate is a salt of carbonic acid (H2CO3), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word ''carbonate'' may also refer to a carbonate ester, an organic compound containing the carbonat ...
s and siliciclastic
Siliciclastic (or ''siliclastic'') rocks are clastic noncarbonate sedimentary rocks that are composed primarily of silicate minerals, such as quartz or clay minerals. Siliciclasic rock types include mudrock, sandstone, and conglomerate
Conglome ...
sediments reminiscent of flysch
Flysch () is a sequence of sedimentary rock layers that progress from deep-water and turbidity flow deposits to shallow-water shales and sandstones. It is deposited when a deep basin forms rapidly on the continental side of a mountain building epi ...
. The Safonovo Group upward end is an unconformity
An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval o ...
that separates it from the poorly sorted sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks.
Most sandstone is composed of quartz or feldspar (both silicates ...
s of the Uftuga Formation.
References
Foreland basins
Geology of European Russia
Sedimentary basins of Europe
Sedimentary basins of Russia
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