|2003 Seattle Annual Meeting (November 2–5, 2003)|
|Paper No. 126-12|
|Presentation Time: 1:30 PM-5:30 PM|
GEOCHEMICAL CHARACTERISTICS OF DEEP-SEA SEDIMENTS (131O10'W-133O50'W, 9O50'-10O30'N FROM THE NORTHEAST EQUATORIAL PACIFIC AND ITS PALEOCEANOGRAPHIC IMPLICATIONS
PARK, Sung-Hyun1, HYEONG, Kiseong1, KIM, Ki-Hyune1, LEE, Kyeong-Yong1, MOON, Jai-Woon1, and LEE, Chang-Bok2, (1) Deep-sea Resources Research Center, Korea Ocean Research and Development Institute, Ansan P.O.Box 29, Seoul, 425-600, email@example.com, (2) Department of Oceanography, Seoul National Univ, Kwanak-Ku, Seoul, 151-742|
Core sediments collected from the Clarion-Clipperton Fracture Zone in the NE equatorial Pacific were analyzed for chemical and mineralogical compositions to investigate the environmental and oceanographic variations along the lengths of cores. The sediments were divided into three lithologic units from top to bottom by its color; brown layer (Unit I), pale brown layer (Unit II), and black brown layer (Unit III). 10Be geochronology indicated the depositional age of Quaternary for Units I and II and of Pliocene for Unit III with a short hiatus between them. Interelemental correlation analyses identified three major groups of elements that showed moderate-to-strong correlations: 1) Al, Ti, K, and Fe, 2) Ca, P, REEs, Cu, and Zn, and 3) Mn, Ni, and Co. Each group reflects terrestrial, biogenic, and hydrogenous Mn-oxide components of sediments, respectively. Unit III shows high smectite, likely formed by dispense of siliceous biogenic components, but low quartz and illite contents compared to the upper two units. This mineralogical variation is accompanied by enriched biogenic components such as P, Cu, and REEs. These indicate the reduced supply of terrestrial material and/or increased productivity of surface water at the time of Unit III deposition, which is attributed to Pliocene warming. However, Unit III contains unidentified 8 angstrom mineral, likely amphibole, that are absent in Units I and II, suggestive of the possibility of different sources during Pliocene. Units I and II show similar elemental and mineral compositions, which indicates stable paleoenvironmental and paleooceanographic conditions through the Quaternary. Increased contribution of terrestrial components, indicated by increased amount of illite and quartz in Units I and II, is consistent with paleoclimatic change from Pliocene warming to a global cooling during Quarternary.
2003 Seattle Annual Meeting (November 2–5, 2003)
|Session No. 126--Booth# 202|
Pliocene Climates—Sea Levels and Ice Volumes (Posters)
Washington State Convention and Trade Center: Hall 4-F
1:30 PM-5:30 PM, Monday, November 3, 2003
Geological Society of America Abstracts with Programs, Vol. 35, No. 6, September 2003, p. 293
© Copyright 2003 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.