HR: 0800h
AN: PP41A-0626    [Abstracts]
TI: Investigating Potential Sources of Titanium-rich Titanomagnetite in Palmer Deep Middle Holocene Sediment
AU: * Cacciapuoti, M A
EM: cacciapuotm1@mail.montclair.edu
AF: Department of Earth and Environmental Studies, Montclair State University, 1 Normal Avenue, Montclair, NJ 07043 United States
AU: Brachfeld, S
EM: brachfelds@mail.montclair.edu
AF: Department of Earth and Environmental Studies, Montclair State University, 1 Normal Avenue, Montclair, NJ 07043 United States
AB: The purpose of this project is to determine the source of titanium-rich titanomagnetite in the middle Holocene Palmer Deep sediments. Magnetic susceptibility records from the Palmer Deep show regularly-spaced highs and lows during the Late Holocene. The middle Holocene sediments have uniformly low susceptibility, which is an order of magnitude lower than the Late Holocene sediments. Late Holocene sediments contain coarse-grained magnetite, which can be traced to the abundant magnetite in the igneous intrusive rocks on the western Antarctic Peninsula. This research focuses on the middle Holocene sediment, which contains titanium-rich titanomagnetite from an unknown source. Sandy-mud samples are being analyzed from the northern and southern ends of Anvers Island, fjords and bays along the western Antarctic Peninsula and a transect down the axis of Bransfield Basin. The 500μm-2mm grains were sieved out and embedded in epoxy for optical microscopy and SEM analysis. Curie temperatures from Anvers Island samples are consistent with pure magnetite and titanium-poor titanomagnetite. The Bransfield Basin samples have Curie temperatures of 100-500° C, which is consistent with titanium-rich titanomagnetite. The combined approaches may reveal shifting ocean current that may be carrying the minerals into the Palmer Deep or changes in ice-rafted debris dispersal paths.
DE: 1512 Environmental magnetism
DE: 1519 Magnetic mineralogy and petrology
DE: 1540 Rock and mineral magnetism
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 3022 Marine sediments: processes and transport
SC: Paleoceanography and Paleoclimatology [PP]
MN: Fall Meeting 2005