| Title | Late Quaternary climate change record from two long sediment cores from Guaymas Basin, Gulf of California |
| Author | Cheshire, H.; Thurow, J.; Nederbragt, A.J. |
| Author Affil | Cheshire, H., University College London, Department of Earth Sciences, London, United Kingdom. Other: University of Wales at Bangor, United Kingdom |
| Source | JQS. Journal of Quaternary Science, 20(5), p.457-469, ; Annually-banded records in the Quaternary, Bangor, United Kingdom, Jan. 6-9, 2004, edited by P. Coxon, J. Scourse, L. Clarke and F. Marret. Publisher: John Wiley and Sons for the Quaternary Research Association, Chichester, United Kingdom. ISSN: 0267-8179 |
| Publication Date | July 2005 |
| Notes | In English. 31 refs. GeoRef Acc. No: 296683 |
| Index Terms | chemical composition; glaciation; isotopes; marine deposits; oxygen; paleoclimatology; Pleistocene; Quaternary deposits; sediments; spectra; Gulf of California--Guaymas Basin; Cenozoic; cores; East Pacific; Guaymas Basin; Gulf of California; Holocene; isotope ratios; laminations; lithostratigraphy; marine sediments; North Pacific; Northeast Pacific; O-18/O-16; Pacific Ocean; planar bedding structures; Quaternary; sea-level changes; sedimentary structures; stable isotopes; upper Pleistocene; X-ray fluorescence spectra |
| Abstract | Modern Guaymas Basin (Gulf of California, Mexico) is a region of high diatom productivity where exceptional preservation factors maintain biannually alternating sediment deposition as annual varves. New sediment cores from Guaymas Basin (MD02-2512 and MD02-2515) present the opportunity to construct climate records from below the last glacial period. A low- resolution age model has been constructed from oxygen isotope analysis, correlation with other dated short piston cores from Guaymas Basin and an estimate of sedimentation rate. MD02-2512 from eastern Guaymas Basin has an age range from the Holocene to late marine isotope stage 6 (MIS 6); MD02-2515 from western Guaymas Basin has an age range from ~8000 to 40 000 yr. Shipboard analyses of colour reflectance, magnetic susceptibility and sediment density are combined with continuous X-ray fluorescence scans to reconstruct a picture of glacial climate in the Gulf of California. Eastern Guaymas Basin is affected by glacial sea level fall, which results in a drastic change in productivity rates and sediment type. The laminated record of MIS 5 allows comparison with the Holocene, showing a similarity of sedimentation patterns during deglaciation and a series of very rapid variations just prior to the last glaciation. In western Guaymas Basin there are a series of Younger Dryas-like events during the glacial, typified by low productivity and high terrigenous input. Long-term climate and productivity changes appear to be caused by the southward displacement of the Subtropical High pressure zone. Abstract Copyright (2005), Wiley Periodicals, Inc. |
| URL | http://hdl.handle.net/10.1002/jqs.944 |
| Publication Type | conference paper or compendium article |
| Record ID | 64001747 |