Structural and Stratigraphic Evolution of the Faeroe-Shetland Channel and Northern Rockall Trough

AbstractThe Voirons Flysch (Caron in Eclogae Geologicae Helvetiae 69:297–308, 1976), is a flysch sequence aggregated into the sedimentary accretionary prism of the Chablais and Swiss Prealps. Its palaeogeographic location is still debated (South Piemont or Valais realm). We herein present a stratigraphic revision of the westernmost unit of the former Gurnigel Nappe sensu Caron (Eclogae Geologicae Helvetiae 69:297–308, 1976): the Voirons Flysch. This flysch is subdivided into three lithostratigraphic units at the formation level (the Voirons Sandstone, the Vouan Conglomerate, the Boëge Marl), with an additional unit (Bruant Sandstone) of uncertain attribution, ranging from the early Eocene to probably the late Eocene. We further propose a new model of the depositional setting of the deep-sea of the Voirons Flysch based on palaeocurrent directions, the overall geometry and sedimentary features. This model depicts an eastward deflected deep-sea fan. The stratigraphic record of the proximal part of this fan is fairly complete in the Voirons area, whereas its most distal part is only represented by one small exposure of thinly bedded sandstones in the Fenalet quarry. The stratigraphic evolution of the Voirons Flysch shows two major disruptions of the detrital sedimentation at the transition between Voirons Sandstone—Vouan Conglomerate and Vouan Conglomerate—Boëge Marl. The cause of these disturbances has to be constrained in the framework of the palaeogeographic location of the Voirons Flysch.

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The stratigraphic evolution of the Lake Tanganyika Rift, East Africa: Facies distributions and paleo-environmental implications

Palaeogeography Palaeoclimatology Palaeoecology ◽

10.1016/j.palaeo.2021.110474 ◽

2021 ◽

pp. 110474

Author(s):

Shaidu Nuru Shaban ◽

Christopher A. Scholz ◽

James D. Muirhead ◽

Douglas A. Wood

Keyword(s):

East Africa ◽

Lake Tanganyika ◽

Environmental Implications ◽

Stratigraphic Evolution

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The Reproductive Biology of Ophiacantha Bidentata (Echinodermata: Ophiuroidea) From The Rockall Trough

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400020099 ◽

1982 ◽

Vol 62 (1) ◽

pp. 45-55 ◽

Cited By ~ 21

Author(s):

P. A. Tyler ◽

J. D. Gage

Keyword(s):

Reproductive Biology ◽

Deep Water ◽

Larval Stage ◽

North Pacific ◽

Deep Sea ◽

Direct Development ◽

The Arctic ◽

Shallow Waters ◽

Arctic Seas ◽

Rockall Trough

INTRODUCTIONOphiacantha bidentata (Retzius) is a widespread arctic-boreal ophiuroid with a circumpolar distribution in the shallow waters of the Arctic seas and penetrating into the deep sea of the.North Atlantic and North Pacific (Mortensen, 1927, 1933a; D'yakonov, 1954). Early observations of this species were confined to defining zoogeo-graphical and taxonomic criteria including the separation of deep water specimens as the variety fraterna (Farran, 1912; Grieg, 1921; Mortensen, 1933a). Mortensen (1910) and Thorson (1936, pp. 18–26) noted the large eggs (o.8 mm diameter) in specimens from Greenland and Thorson (1936) proposed that this species had ‘big eggs rich in yolk, shed directly into the sea. Much reduced larval stage or direct development’. This evidence is supported by observations of O. bidentata from the White and Barents Seas (Semenova, Mileikovsky & Nesis, 1964; Kaufman, 1974)..

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