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Full-Text Articles in Life Sciences
Bioactive Trace Metals And Their Isotopes As Paleoproductivity Proxies: An Assessment Using Geotraces-Era Data, T. J. Horner, S. H. Little, T. M. Conway, J. R. Farmer, J. E. Hertzberg, D. J. Janssen, A. J. M. Lough, J. L. Mckay, A. Tessin, S. J. G. Galer, S. L. Jaccard, F. Lacan, A. Paytan, K. Wuttig, Geotraces–Pages Biological Productivity Working Group Members
Bioactive Trace Metals And Their Isotopes As Paleoproductivity Proxies: An Assessment Using Geotraces-Era Data, T. J. Horner, S. H. Little, T. M. Conway, J. R. Farmer, J. E. Hertzberg, D. J. Janssen, A. J. M. Lough, J. L. Mckay, A. Tessin, S. J. G. Galer, S. L. Jaccard, F. Lacan, A. Paytan, K. Wuttig, Geotraces–Pages Biological Productivity Working Group Members
Marine Science Faculty Publications
Phytoplankton productivity and export sequester climatically significant quantities of atmospheric carbon dioxide as particulate organic carbon through a suite of processes termed the biological pump. Constraining how the biological pump operated in the past is important for understanding past atmospheric carbon dioxide concentrations and Earth's climate history. However, reconstructing the history of the biological pump requires proxies. Due to their intimate association with biological processes, several bioactive trace metals and their isotopes are potential proxies for past phytoplankton productivity, including iron, zinc, copper, cadmium, molybdenum, barium, nickel, chromium, and silver. Here, we review the oceanic distributions, driving processes, and depositional …
Site U1521, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Site U1521, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Marine Science Faculty Publications
No abstract provided.
Expedition 374 Methods, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Expedition 374 Methods, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Marine Science Faculty Publications
This chapter documents the procedures and methods employed during drilling operations and in the shipboard laboratories on the R/V JOIDES Resolution during International Ocean Discovery Program (IODP) Expedition 374. This information applies only to the shipboard work described in the Expedition Reports section of the Expedition 374 Proceedings of the International Ocean Discovery Programvolume. Methods used by investigators for shore-based analyses of Expedition 374 data and samples will be described in separate individual publications. This introductory section provides an overview of drilling and coring operations, core handling, curatorial conventions, depth scale terminology, and the sequence of shipboard analyses. Subsequent …
Expedition 374 Summary, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Expedition 374 Summary, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Marine Science Faculty Publications
The marine-based West Antarctic Ice Sheet (WAIS) is currently locally retreating because of shifting wind-driven oceanic currents that transport warm waters toward the ice margin, resulting in ice shelf thinning and accelerated mass loss. Previous results from geologic drilling on Antarctica’s continental margins show significant variability in ice sheet extent during the late Neogene and Quaternary. Climate and ice sheet models indicate a fundamental role for oceanic heat in controlling ice sheet variability over at least the past 20 My. Although evidence for past ice sheet variability is available from ice-proximal marine settings, sedimentary sequences from the continental shelf and …
Site U1525, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Site U1525, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Marine Science Faculty Publications
No abstract provided.
Site U1524, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Site U1524, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Marine Science Faculty Publications
No abstract provided.
Site U1522, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Site U1522, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Marine Science Faculty Publications
No abstract provided.
Site U1523, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Site U1523, Robert M. Mckay, Laura De Santis, Denise K. Kulhanek, Imogen M. Browne, Amelia E. Shevenell, Expedition 374 Scientists
Marine Science Faculty Publications
No abstract provided.
Benjamin P. Flower (1962–2012), David W. Hastings, Amelia E. Shevenell, James P. Kennett
Benjamin P. Flower (1962–2012), David W. Hastings, Amelia E. Shevenell, James P. Kennett
Marine Science Faculty Publications
Benjamin P. Flower, a gifted paleoceanographer and marine geologist, supportive colleague, and dedicated educator at the University of South Florida (USF) College of Marine Science (CMS) passed away on 1 July 2012 from complications related to a rare genetic immune dysfunction, Common Variable Immunodeficiency. He was 49 years old. During his brief illness, Ben's love of life and boundless high spirits were an inspiration to his family, friends, and colleagues. He exhibited remarkable courage and kept his sense of humor in face of adversity. Ben's intellectualism and enduring love of science remained intact, even in his last hours.
Middle Miocene Ice Sheet Dynamics, Deep‐Sea Temperatures, And Carbon Cycling: A Southern Ocean Perspective, Amelia E. Shevenell, James P. Kennett, David W. Lea
Middle Miocene Ice Sheet Dynamics, Deep‐Sea Temperatures, And Carbon Cycling: A Southern Ocean Perspective, Amelia E. Shevenell, James P. Kennett, David W. Lea
Marine Science Faculty Publications
Relative contributions of ice volume and temperature change to the global ∼1‰ δ18O increase at ∼14 Ma are required for understanding feedbacks involved in this major Cenozoic climate transition. A 3‐ma benthic foraminifer Mg/Ca record of Southern Ocean temperatures across the middle Miocene climate transition reveals ∼2 ± 2°C cooling (14.2–13.8 Ma), indicating that ∼70% of the increase relates to ice growth. Seawater δ18O, calculated from Mg/Ca and δ18O, suggests that at ∼15 Ma Antarctica's cryosphere entered an interval of apparent eccentricity‐paced expansion. Glaciations increased in intensity, revealing a central role for internal climate …
Surface And Deep Ocean Circulation In The Subpolar North Atlantic During The Mid-Pleistocene Revolution, Amy K. Wright, Benjamin P. Flower
Surface And Deep Ocean Circulation In The Subpolar North Atlantic During The Mid-Pleistocene Revolution, Amy K. Wright, Benjamin P. Flower
Marine Science Faculty Publications
We investigated surface and deep ocean variability in the subpolar North Atlantic from 1000 to 500 thousand years ago (ka) based on two Ocean Drilling Program (ODP) sites, Feni drift site 980 (55°29′N, 14°42′W) and Bjorn drift site 984 (61°25′N, 24°04′W). Benthic foraminiferal stable isotope data, planktic foraminiferal faunas, ice‐rafted debris data, and faunally based sea‐surface temperature estimates help test the hypothesis that oceanographic changes in the North Atlantic region were associated with the onset of the 100‐kyr world during the mid‐Pleistocene revolution. Based on percentage of Neogloboquadrina pachyderma (s) records from both sites, surface waters during interglacials and glacials …
Orbitally-Tuned Sr Isotope Chemostratigraphy For The Late Middle To Late Miocene, E. E. Martin, N. J. Shackleton, J. C. Zachos, Benjamin P. Flower
Orbitally-Tuned Sr Isotope Chemostratigraphy For The Late Middle To Late Miocene, E. E. Martin, N. J. Shackleton, J. C. Zachos, Benjamin P. Flower
Marine Science Faculty Publications
We present a Sr chemostratigraphic reference section for the late middle to late Miocene (14-5 Ma) from Ocean Drilling Program site 926 on the Ceara Rise. This site combines a precise, orbitally tuned timescale with a high sedimentation rate (15 m/m.y.), continuous deposition, and excellent biostratigraphic control. The Sr isotope curve is based on measurements of cleaned, planktonic foraminifera at 100-200 kyr sample intervals and it illustrates periods of rapid change in Sr-87/Sr-86 alternating with periods of little change. Chemostratigraphically-defined ages for these intervals can be determined within +/-0.8 m.y. and +/-1.6 m.y, respectively. There is excellent correlation with the …