5,401 research outputs found
(Table T2) Accumulation rates, carbonate content and stable isotopes of ODP Hole 199-1219A sediments
No full textDepth, sediment is given in mbsf. Age from H. Pälike, unpubl. data. For more data from Boise State University see Olivarez-Lyle and Lyle dataset: http://doi.pangaea.de/10.1594/PANGAEA.777223
IODP Proposal 626: "Cenozoic Equatorial Age Transect – Following the Palaeo-equator"
No full textAs the largest ocean, the Pacific is intricately linked to major changes in the global climate system that took place during the Cenozoic. Throughout the Cenozoic the Pacific plate has had a northward component. Thus, the Pacific is unique, in that the thick sediment bulge of biogenic rich deposits from the currently narrowly focused zone of equatorial upwelling is slowly moving away from the equator. Hence, older sections are not deeply buried and can be recovered by drilling. Previous ODP Legs 138 and 199 were designed as transects across the paleo-equator in order to study the changing patterns of sediment deposition across equatorial regions, while this proposal aims to recover an orthogonal “age-transect” along the paleo-equator. Both previous legs were remarkably successful in giving us new insights into the workings of the climate and carbon system, productivity changes across the zone of divergence, time dependent calcium carbonate dissolution, bio- and magnetostratigraphy, the location of the ITCZ, and evolutionary patterns for times of climatic change and upheaval. Together with older DSDP drilling in the eastern equatorial Pacific, both Legs also helped to delineate the position of the paleo-equator and variations in sediment thickness from approximately 150°W to 110°W. As we have gained more information about the past movement of plates, and where in time “critical” climate events are located, we now propose to drill an age-transect (“flow-line”) along the position of the paleo-equator in the Pacific, targeting selected time-slices of interest where calcareous sediments have been preserved best. Leg 199 enhanced our understanding of extreme changes of the calcium carbonate compensation depth across major geological boundaries during the last 55 million years. A very shallow CCD during most of the Paleogene makes it difficult to obtain well preserved sediments, but we believe our siting strategy will allow us to drill the most promising sites and to obtain a unique sedimentary biogenic carbonate archive for time periods just after the Paleocene- Eocene boundary event, the Eocene cooling, the Eocene/Oligocene transition, the “one cold pole” Oligocene, the Oligocene-Miocene transition, and the Miocene, contributing to the objectives of the IODP Extreme Climates Initiative, and providing material that the previous legs were not able to recover
Expedition 320/321 summary
No full textIntegrated Ocean Drilling Program Expedition 320/321, "Pacific Equatorial Age Transect" (Sites U1331–U1338), was designed to recover a continuous Cenozoic record of the equatorial Pacific by coring above the paleoposition of the Equator at successive crustal ages on the Pacific plate. These sediments record the evolution of the equatorial climate system throughout the Cenozoic. As we gained more information about the past movement of plates and when in Earth's history "critical" climate events took place, it became possible to drill an age transect ("flow-line") along the position of the paleoequator in the Pacific, targeting important time slices where the sedimentary archive allows us to reconstruct past climatic and tectonic conditions. The Pacific Equatorial Age Transect (PEAT) program cored eight sites from the sediment surface to basement, with basalt aged between 53 and 18 Ma, covering the time period following maximum Cenozoic warmth, through initial major glaciations, to today. The PEAT program allows the reconstruction of extreme changes of the calcium carbonate compensation depth (CCD) across major geological boundaries during the last 53 m.y. A very shallow CCD during most of the Paleogene makes it difficult to obtain well-preserved carbonate sediments during these stratigraphic intervals, but Expedition 320 recovered a unique sedimentary biogenic sediment archive for time periods just after the Paleocene/Eocene boundary event, the Eocene cooling, the Eocene–Oligocene transition, the "one cold pole" Oligocene, the Oligocene–Miocene transition, and the middle Miocene cooling. Expedition 321, the second part of the PEAT program, recovered sediments from the time period roughly from 25 Ma forward, including sediments crossing the Oligocene/Miocene boundary and two major Neogene equatorial Pacific sediment sections. Together with older Deep Sea Drilling Project and Ocean Drilling Program drilling in the equatorial Pacific, we can delineate the position of the paleoequator and variations in sediment thickness from ~150°W to 110°W longitude
Summary report of R/V Roger Revelle Site Survey AMAT03 to the IODP Environmental Protection and Safety Panel (EPSP) in support for proposal IODP626
No full text[David Mitchell and Descendants]
No full textCopy of "David Mitchell and Descendants" originally written by Thomas Mitchell, Jr. The manuscript starts with David Mitchell, possibly a Revolutionary soldier, and details what is known about his life and those of his descendants. The record ends with the marriage of his widow, Sarah Patterson Mitchell Frear, to Abraham Frear. It states that she was the mother and grandmother of many Frears and Mitchells in the family. After the record, there is a note about the original manuscript's author; it was then copied by Ora Osterhout
In the Garden, Danielle Mitchell, Spring 2020
No full textDanielle Mitchell is a rising senior from Compton, California majoring in anthropology and sociology. She is a gifted writer who conducted very special interviews in SIS Seminar
Hall Street, Danielle Mitchell, Spring 2020
No full textDanielle Mitchell is a rising senior from Compton, California majoring in anthropology and sociology. She is a gifted writer who conducted very special interviews in SIS Seminar
Peer Interview Script, Danielle Mitchell, Spring 2020
No full textDanielle Mitchell is a rising senior from Compton, California majoring in anthropology and sociology. She is a gifted writer who conducted very special interviews in SIS Seminar
Data to reconstruct biogenic sedimentary component time series from the Miocene Pacific to study the biological pump
No full textWe measured over 1,600 samples for POC and CaCO3, from 5 Sites of the Deep-Sea Drilling Project, Ocean Drilling Program, and Integrated Ocean Drilling Program (Sites 574, 884, 1208, U1337, and U1338) from the equatorial Pacific and North Pacific. Freeze-dried sediment samples were analyzed using coulometry and furnace methodologies presented in Lyle et al., (2000) which provide accurate POC values at very low levels. These data were analyzed from 2008 to 2012. We include XRF data for Sites 574, and interpreted XRF data for Sites U1337 and U1338. We have also included data reported for Sites 806 and 807 (Stax and Stein, 1993) from the western equatorial Pacific. We made a continuous sediment splice for Site 574 and created new age models for all drill sites to calculate mass accumulation rates to ~20 million years ago or to the base of the Neogene sediments at each drill site. Age models are also presented in the data sets
Excerpts of Interviews with Peers, Danielle Mitchell, Spring 2020
No full textDanielle Mitchell is a rising senior from Compton, California majoring in anthropology and sociology. She is a gifted writer who conducted very special interviews in SIS Seminar
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