Benthic foraminifera in the surface sediments of the deep-sea Arctic Ocean

Abstract

Modern distributions of Arctic deep-sea benthonic foraminifera were examined from four expeditions -CESAR, LOREX, Fram I1 and 111. The samples covered a broad water depth range (800-4,200 m) and a wide range of Arctic environments from near the Fram Straits to the Alpha Ridge in the central Arctic basin. For the first time, diverse agglutinated assemblages were found in deep-sea Arctic material, near the Fram Strait in 800-1,000 m of water. We also observed a fauna unique to the deep Eurasian Basin (> 3,700 m) with 95%

Response of Recent Benthic Foraminiferal Assemblages to Contrasting Environments in Baffin Bay and the Northern Labrador Sea, Northwest Atlantic

“…The lack of calcareous fauna in this area of Baffin Bay agrees well with the shallow CCD between 600 and 900 m in this region, as suggested by Aksu (1983), who found that the carbonate content of sediment samples decreased rapidly below 300 m in depth. Scott and Vilks (1991) reported similar results from the Yermak Plateau in the Arctic Ocean and proposed that the absence of calcareous species from some parts of the Arctic shelf is due to the presence of corrosive water that inhibits secretion of calcareous tests, as well as removing any calcium carbonate present in the water column before it can accumulate in sediments. The absence of calcareous foraminifera on the Yermak Plateau is unusual because most of the Arctic shelf is characterized by mixed faunas that contain both calcareous and agglutinated species (Phleger, 1952;Loeblich and Tappan, 1953;Vilks, 1969;Lagoe, 1977;Wollenburg, 1992).…”

“…The absence of calcareous foraminifera on the Yermak Plateau is unusual because most of the Arctic shelf is characterized by mixed faunas that contain both calcareous and agglutinated species (Phleger, 1952;Loeblich and Tappan, 1953;Vilks, 1969;Lagoe, 1977;Wollenburg, 1992). Other areas in the Arctic where carbonate dissolution is an important factor are the Laptev Sea (Wollenburg and Kuhnt, 2000), the Fram Basin (Scott and Vilks, 1991), and areas of the western Canadian Archipelago (Vilks, 1989). Wollenburg and Kuhnt (2000) stated that carbonate dissolution in the Arctic Ocean increases with decreasing water depth and increasing duration of ice retreat, whereas calcareous faunas under perennial ice cover remain well preserved.…”

Different benthic size-compartments and their relationship to sediment chemistry in the deep Eurasian Arctic Ocean

“…Before 1991, benthic investigations were carried out in the Canadian Archipelago by Paul & Menzies (1974) and Thompson (1982) between 75" and 85" N. Few studies investigated foraminifera of the central Eurasian Basin (Scott & Vilks 1991).…”

Arctic Ocean Benthic Foraminiferal Faunae Change Associated with the Onset of Perennial Sea Ice in the Middle Miocene

“…2E, J), which remains a persistent component of A3. Although not recorded in core top studies of the Arctic Ocean (Belanger and Streeter, 1980;Schröder-Adams and others, 1990;Scott and Vilks, 1991;Wollenburg and Kuhnt, 2000), on the Lomonosov Ridge, A. polarensis became much reduced after Marine Isotope Stages 22-24 (~0.9 Ma) in Hole M0004C (Cronin and others, 2008), and disappeared on the Lomonosov Ridge above 2 m in Hole PS 2185-6 (Evans and Kaminski, 1998), which equates to ~0.14 Ma using the ACEX age model (Fig. 5).…”

“…In contrast the perennially ice-covered central Arctic contains less variable assemblages including Stetsonia arctica and Adercotryma glomerata (Scott and Vilks, 1991;Wollenburg and Kuhnt, 2000). summer melting assuming modern sea-ice trajectories and velocities (Krylov and others, 2008).…”