Results 91 to 100 of about 3,343 (212)

Distribution of branched glycerol dialkyl glycerol tetraether (brGDGT) lipids from soils and sediments from the same watershed are distinct regionally (central Chile) but not globally

Frontiers in Earth Science
Quantitative reconstructions of past continental climates are vital for understanding contemporary and past climate change. Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are unique bacterial lipids that have been proposed as universal ...
Molly D. O’Beirne, Wesley P. Scott, Sergio Contreras, Sergio Contreras, Sergio Contreras, A. Araneda, E. Tejos, J. Moscoso, Josef P. Werne   +8 more
doaj   +1 more source

Enhancing paleoclimate reconstructions in the late Aptian North-Northeast Brazil using clay mineralogy

Evolving Earth
Paleoclimate changes are commonly analyzed on three distinct scales: small-scale (20–500 kyr), linked to Milankovitch cycles; medium-scale events (∼30 Myr), associated with sea-level changes and tectonic activity; and large-scale (∼300 Myr), related to ...
Victor Matheus Joaquim Salgado-Campos, Luiz Carlos Bertolino, Leonardo Borghi, Aristóteles de Moraes Rios-Netto, Bruno Cesar Araújo, Danielle Cardoso de Souza, Laís de Oliveira Ferreira, Fabia Emanuela Rafaloski Bobco, Jéssica de Souza Gabi Barcellos, Ismar de Souza Carvalho   +9 more
doaj   +1 more source

Crenarchaeotal membrane lipids in lake sediments : a new paleotemperature proxy for continental paleoclimate reconstruction?

, 2004
Paleoclimate studies of continental environments have been hampered by the lack of an independent paleotemperature proxy. A novel sea-surface temperature proxy has been proposed for marine systems based on membrane lipids of marine crenarchaeota.
Hopmans, E.C., Powes, L.A., Johnson, T.C., Schouten, S., Sinninghe Damsté, J.S., Werne, J.P.   +5 more
core  

Burial-induced oxygen-isotope re-equilibration of fossil foraminifera explains ocean paleotemperature paradoxes

Nature Communications, 2017
The oxygen-isotope composition of fossil foraminifera tests is an established proxy for ocean paleotemperatures. Here, the authors show that isotope re-equilibration can occur during sediment burial without structural modification of the tests and cause ...
S. Bernard, D. Daval, P. Ackerer, S. Pont, A. Meibom   +4 more
doaj   +1 more source

Late Oligocene Warming Event in the southern North Sea Basin: benthic foraminifera as paleotemperature proxies [PDF]

, 2004
The investigation of foraminiferal assemblages from a series of Oligocene borehole sections allowed paleoenvironment and paleoclimate reconstructions for the Rupelian and Chattian (Lower and Upper Oligocene) Stages in their type region, the southern ...
Van Simaeys, S., De Man, E.
core  

Paleotemperature reconstruction from the late Quaternary deep-sea sediment based on oxygen isotope and alkenones data in the East Sea (Sea of Japan)

, 2005
Paleoenvironmental changes since the last ~ 250 ka was reconstructed based on the oxygen isotope compositions of forminifera and alkenons data from the deep-sea sediments of the piston core (M04-PC1A) taken from the Korea Plateau in the East Sea (Japan ...
현상민, 김정무, 심원준, 윤석훈, 석봉출, 우경식   +5 more
core  

Stable isotope records of hydrologic change and paleotemperature from smectite in Cenozoic western North America

, 2014
The oxygen and hydrogen isotopic composition of soil water (δ18Ow and δDw hereafter) reflect the history of water through processes such as source evaporation, precipitation and vapor recycling.
Chamberlain, Charles P., Mix, Hari T.
core   +1 more source

Can pedogenic carbonate provide a paleotemperature record from ice-free areas of Antarctica?

The aim of the study was to determine whether or not pedogenic (soil) carbonate in Antarctic soils can be used to construct a paleotemperature ...
Bockheim, Shanhun, F, Almond, Peter, Smith, Carol, Clough, Timothy   +4 more
core  

(Table 9) Isotopic composition of oxygen from CaCO3 of planktonic foraminifera complexes in bottom sediments of Core ML3_198-4GC and calculated paleotemperatures

, 1988
(Table 9) Isotopic composition of oxygen from CaCO3 of planktonic foraminifera complexes in bottom sediments of Core ML3_198-4GC and calculated ...
Barash, Max S, Max S Barash (6887036)
core   +1 more source

The Branched GDGT Isomer Ratio Refines Lacustrine Paleotemperature Estimates

Geochemistry, Geophysics, Geosystems
Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are membrane‐spanning lipids synthesized by bacteria in numerous substrates. The degree of methylation of the five methyl brGDGTs in both soils and lake sediments, described by the MBT′5Me index ...
Joseph B. Novak, James M. Russell, Emma R. Lindemuth, Alexander A. Prokopenko, Lina Pérez‐Angel, Boyang Zhao, George E. A. Swann, Pratigya J. Polissar   +7 more
doaj   +1 more source