Download or read book Equatorial Pacific Sediments written by Barbara Ann Price and published by . This book was released on 1988 with total page 800 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Paleoredox and Color Change in Equatorial Pacific Sediments written by Wendy E. C. Kordesch and published by . This book was released on 2011 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Correlation of Cenozoic Deep Sea Sediments of the Equatorial Pacific Ocean written by Richard G. Blank and published by . This book was released on 1977 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Equatorial Pacific Sediment Deposition During the Early to Middle Miocene written by Christine Marie Piela and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The equatorial Pacific is a major region of biological production in the world oceans and an important part of the global carbon cycle. Changes in climate during the Cenozoic (65 Ma to present) have impacted the carbon cycle, and it is important to assess these impacts. This study focuses on the primary productivity of the equatorial Pacific during the early to middle Miocene (24 - 12 Ma) as recorded by Deep Sea Drilling Project (DSDP) Site 574, and investigates the sedimentary components potentially linked to productivity: bio-Ba, bio-SiO2, Corg, CaCO3, and uranium, as well as detrital thorium to estimate clay-bound barium. Within this time frame the plate beneath Site 574 traveled northwesterly across the equator and allows a unique opportunity to monitor changes in productivity and the carbon cycle in this region. It is difficult to determine directly primary productivity from the sedimentary record because the preservation of different proxies for this parameter - Corg, bio-CaCO3, and bio-SiO2, can be highly variable. The variability has many causes, including nutrient recycling in the water column and the depth of the carbonate compensation depth (CCD), which prevents the preservation and ultimate burial of plankton debris at the seafloor. To interpret the production versus deposition rates during the early and middle Miocene, proxies were used in conjunction with direct measurements of biogenic remains. By determining the concentrations of biogenically produced barium (bio-Ba), which is less affected by degradation, it is evident that the mass of Corg produced was much greater than that preserved in the sediments. We observed higher deposition of bio-Ba and bio- SiO2 as the site was transported over the equatorial divergence by plate tectonics, as expected. In contrast, CaCO3, accumulation was low in the divergence region, and coincides with a dissolution event known from other site studies in the equatorial Pacific. The pattern of uranium deposition resembles CaCO3 and Corg, and average U concentrations suggest that it was primarily deposited as a trace element in the shell material of biogenic carbonate. Corg also resembles CaCO3 and appears to represent primarily a dissolution signal. Total uranium analysis proved to be a useful proxy for Corg and CaCO3 preservation, and analysis of detrital thorium (232Th) concentration suggests very limited terrigenous clay input. Comparison of the different proxies reveals carbonate preservation events, changes in Corg preservation, and changes in deposition as DSDP Site 574 migrated northwesterly across the equator.

Download or read book Miocene Sediments of the Equatorial Pacific Ocean written by Dean Alan Dunn and published by . This book was released on 1982 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Recent and Late Pleistocene Sediments from the Eastern Equatorial Pacific Ocean written by Charles Gordon Adelseck and published by . This book was released on 1977 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Eastern Equatorial Pacific Ocean Sedimentation written by Ajay Kumar Singh and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Age-model derived sediment mass accumulation rates (MARs) are consistently higher than 230Th-normalized MARs in the Equatorial Pacific Ocean during the past 25 ka. The offset, being highest in the Panama Basin, suggests sediment redistribution in this region is prominent. I test the hypothesis that downslope transport of sediments from topographically highs that surround the Panama Basin is the cause of higher-than-expected xs230Th inventories in the deeper parts of the basin. There is little difference in xs230Th inventories between the highest and lowest reaches of the basin suggesting that the topographic highs did not serve as a source of xs230Th. A spatial analysis suggests that there may be an enhanced scavenging of xs230Th closest to the equator in productive waters. To examine whether lateral mixing of productive equatorial waters with adjacent waters delivers xs230Th to the Panama Basin, I measured dissolved 230Th in eight deep-water casts within the Guatemala, Panama, and Peru Basins along a meridional transect at ~86°W. Below 1000 m, the Panama Basin shows the highest deficit (~50%) of 230Th in deep waters assuming a reversible exchange of 230Th between dissolved and sinking particulate matter. Peru Basin waters have a larger range of dissolved 230Th concentrations (7.9-16.5 fg/kg) than that within Panama Basin waters (5.7-7.1 fg/kg). There is a progressive decrease, suggesting advection, in average dissolved deep-water (>1000 m) 230Th concentrations from the southernmost sites in the Peru Basin toward the Panama Basin. My calculations suggest that advected 230Th is between 15-30% of the total 230Th being produced within waters of the Panama Basin itself. In the Panama Basin, the averaged biogenic barium and opal MARs suggest that productivity was greater during the Holocene (0-13000 years) than that during the last glacial (13000-25000 years) suggesting higher productivity during the Holocene. Uauth, however, is higher in sediments deposited during the last glacial than in those deposited during the Holocene, suggesting that low bottom water oxygen contents rather than respiration of organic matter drives Uauth enrichment. This oxygen depletion during the last glacial suggests that bottom waters were enriched in respired carbon, which, in turn, could be a driver of lower glacial atmosphere pCO2 values. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/148258

Download or read book Bioturbation of Recent Abyssal Sediments in the Eastern Equatorial Pacific written by Peter Franklin Bryant and published by . This book was released on 1977 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reports of the Swedish Deep Sea Expedition 1947 1948 Sediment cores from the East Pacific written by Hans Pettersson and published by . This book was released on 1951 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Biogenic Sediments on the Eauripik Rise of the Western Equatorial Pacific During the Late Pleistocene written by H. Kawahata and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Backtracking and Forward Tracking of Sediments in the East Equatorial Pacific A Test of Assumptions written by J. L. Matthews and published by . This book was released on 1976 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical models are used to show that sediment thicknesses younger than Eocene in the east quatorial Pacific can be predicted by specifying paleolatitude, paleodepth, and time. Error analysis shows the effect of mistakes in the estimate of basement age and pole position on prediction of rate of sedimentation. (Author).

Download or read book Backtracking and Forward Tracking of Sediments in the East Equatorial Pacific A Test of Assumptions written by and published by . This book was released on 1976 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical models are used to show that sediment thicknesses younger than Eocene in the east quatorial Pacific can be predicted by specifying paleolatitude, paleodepth, and time. Error analysis shows the effect of mistakes in the estimate of basement age and pole position on prediction of rate of sedimentation. (Author).

Download or read book Geochemical Indicators of Palaeoproductivity and Palaeoclimate in Eastern Equatorial Pacific Sediments written by Andrew John Patience and published by . This book was released on 1992 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Uranium series Disequilibrium Studies of the East Equatorial Pacific Sediments written by Yong-Liang Yang and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Paleoceanographic Interpretations of the Pleistocene Sediments from the Eastern Equatorial Pacific ODP Hole 677B written by Yee-Hwa Lin and published by . This book was released on 1990 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Selective Kinetic Extractions of Some Northeastern Equatorial Pacific Pelagic Sediments written by Barbara Alison Mills and published by . This book was released on 1978 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Indicators and Tracers of Ocean Chemistry Change Over the Pleistocene written by Rachel Oxburgh and published by . This book was released on 1996 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: