Paper No. 14
Presentation Time: 8:00 AM-6:00 PM
FORAMINIFERAN AND OSTRACODA FROM LAKE CORE 98-2-A AT BARROW, ARCTIC ALASKA
This paper deals with foraminiferan and ostracoda sediments in the Arctic lake at Barrow. The lake core 98-2-A with length of 77 cm was from Elson Lagoon ( 71o 17¢53²N, 156o 24¢07²W ) under water of a depth of 2.6 m. The whole of the core was separated by centimetre). 11 species of foraminiferan belonging to 7 genera from 45 samples of the core are Ammotium cassis (Parker), Asterellina pulchella (Parker), Buccella frigida (Cushman), Elphidium bartletti Cushman, Elphidium clavatum Cushman, Elphidium excavatum alba Feyling-Hanssen, Elphidium orbiculare (Brady), Elphidium sp., Elphidiella groenlandica (Cushman), Polymorphina sp., and Trochammina nana (Brady). Ostracoda collected from 5 samples are Cytheromorpha macchesneyi (Brady and Crosskey), Para cyprideis pseudopunctillata, Heterpcyprideis sorbyana (Jones), Paracyprideis pseudopunctillata Swain, and Rabilimis septentrionalis (Brady). These foraminiferan and ostracoda distributed in the core have four sediment stages. First stage (77-65cm) is at bottom of the core, the species of foraminiferan are only 2 belonging to Elphidium genera. Environment in the time didn¢t fit the growth of foraminiferan. Second stage (65-28cm) has Asterellina pulchella, Elphidium clavatum Cushman, Elphidium excavatum alba Feyling-Hanssen, Elphidium orbiculare, Elphidium sp., and Elphidiella groenlandica. Elphidium sp. is prevalent. Body and hull of foraminifer are almost fragmentized, and their color is light yellow. It show they are foreign. It is high energy environment under surf. Third stage (28-11cm) has Elphidium sp., Asterellina pulchella, and Elphidium orbiculare, et al. The population is many, and their color is milk white. They are belonging to a place by birth. Ostracoda has still Cytheromorpha macchesneyi, Para cyprideis pseudopunctillata, and Heterpcyprideis sorbyana in the stage. Sea level was high in the stage. Fourth stage (11-0cm) has Asterellina pulchella, Trochammina nana, and Elphidium sp.. But their population is small. Ostracoda has a small quantity of Paracyprideis pseudopunctillata Swain, and Rabilimis septentrionalis. This is particularities of foraminiferan and ostracoda in modern environment at Barrow, Arctic. This research was financially supported by funding from National Natural Science Foundation of China (49971078).