Age model and color measurements of sediment cores from the eastern equatorial Pacific


Autoria(s): Weber, Michael E; Pisias, Nicklas G
Cobertura

MEDIAN LATITUDE: -6.649778 * MEDIAN LONGITUDE: -89.557504 * SOUTH-BOUND LATITUDE: -8.545000 * WEST-BOUND LONGITUDE: -90.826300 * NORTH-BOUND LATITUDE: -5.108333 * EAST-BOUND LONGITUDE: -85.372833 * DATE/TIME START: 1992-01-01T00:00:00 * DATE/TIME END: 1996-02-27T00:00:00

Data(s)

07/05/1999

Resumo

High-resolution records of glacial-interglacial variations in biogenic carbonate, opal, and detritus (derived from non-destructive core log measurements of density, P-wave velocity and color; r >= 0.9) from 15 sediment sites in the eastern equatorial (sampling resolution is ~1 kyr) clear response to eccentricity and precession forcing. For the Peru Basin, we generate a high-resolution (21 kyr increment) orbitally-based chronology for the last 1.3 Ma. Spectral analysis indicates that the 100 kyr cycle became dominant at roughly 1.2 Ma, 200-300 kyr earlier than reported for other paleoclimatic records. The response to orbital forcing is weaker since the Mid-Brunhes Dissolution Event (at 400 ka). A west-east reconstruction of biogenic sedimentation in the Peru Basin (four cores; 91-85°W) distinguishes equatorial and coastal upwelling systems in the western and eastern sites, respectively. A north-south reconstruction perpendicular to the equatorial upwelling system (11 cores, 11°N-°3S) shows high carbonate contents (>= 50%) between 6°N and 4°S and highly variable opal contents between 2°N and 4°S. Carbonate cycles B-6, B-8, B-10, B-12, B-14, M-2, and M-6 are well developed with B-10 (430 ka) as the most prominent cycle. Carbonate highs during glacials and glacial-interglacial transitions extended up to 400 km north and south compared to interglacial or interglacial^glacial carbonate lows. Our reconstruction thus favors glacial-interglacial expansion and contraction of the equatorial upwelling system rather than shifting north or south. Elevated accumulation rates are documented near the equator from 6°N to 4°S and from 2°N to 4°S for carbonate and opal, respectively. Accumulation rates are higher during glacials and glacial-interglacial transitions in all cores, whereas increased dissolution is concentrated on Peru Basin sediments close to the carbonate compensation depth and occurred during interglacials or interglacial-glacial transitions.

Formato

application/zip, 37 datasets

Identificador

https://doi.pangaea.de/10.1594/PANGAEA.714902

doi:10.1594/PANGAEA.714902

Idioma(s)

en

Publicador

PANGAEA

Direitos

CC-BY: Creative Commons Attribution 3.0 Unported

Access constraints: unrestricted

Fonte

Supplement to: Weber, Michael E; Pisias, Nicklas G (1999): Spatial and temporal distribution of biogenic carbonate and opal in deep-sea sediments from the eastern equatorial Pacific: implications for ocean history since 1.3 Ma. Earth and Planetary Science Letters, 174(1-2), 59-73, doi:10.1016/S0012-821X(99)00248-4

Palavras-Chave #181KL; 184KL; 189KL; 206KL; 217KL; 222SL; 229KL; 235KL; 243KL; 244KA; 249KL; 251KL; 254KL; 261KA; 268KA; 272KA; 276KL; 278KA; 286KL; a*; Age model; Age model, orbital calibration (Laskar, 1990); ATESEPP; b*; Color, a*; Color, b*; Color, L*, lightness; Depth; DEPTH, sediment/rock; Gravity corer (Kiel type); KAL; Kasten corer; KL; L*; Peru Basin; Piston corer (BGR type); SEDIPERU - TUSCH; SL; SO106/1; SO106/1_181KL; SO106/1_184KL; SO106/1_189KL; SO106/1_206KL; SO106/1_217KL; SO106/1_222SL; SO106/1_229KL; SO106/1_235KL; SO106/2; SO106/2_243KL; SO106/2_244KA; SO106/2_249KL; SO106/2_251KL; SO106/2_254KL; SO106/2_261KA; SO106/2_268KA; SO106/2_272KA; SO106/2_276KL; SO106/2_278KA; SO106/2_286KL; SO79; SO79_108KL; SO79_136KL; SO79_164KL; SO79_169KL; SO79_26KL; SO79_48KL; SO79_53KL; SO79_71KL; SO79_77KL; SO79_82KL; SO79_85KL; SO79_9KL; Sonne; Spectrophotometer Minolta CM-2022
Tipo

Dataset