Results 31 to 40 of about 266 (168)

Evidence for Limited Atmospheric CO2 Rise at the Miocene Climatic Optimum

open access: yesPaleoceanography and Paleoclimatology, Volume 41, Issue 6, June 2026.
Abstract The Miocene Climatic Optimum (MCO; 16.9–14.7 Ma) was a relatively warm period with atmospheric CO2 averaging ∼500 μatm but CO2 change across its onset is poorly documented. We present a record of algal 13C‐fractionation covering the Early to Middle Miocene (∼18.5–15 Ma), with a gap at the MCO onset, from Ocean Drilling Program Site 959 in the ...
Evi Wubben   +9 more
wiley   +1 more source

Disentangling environmental drivers of Subarctic dinocyst assemblage compositional change during the Holocene

open access: yesClimate of the Past, 2023
Abstract. Analysis of compositional changes in fossil organic-walled dinoflagellate cyst (dinocysts) assemblages is a widely used tool for the quantitative reconstruction of past environmental parameters. This approach assumes that the assemblage composition is significantly and independently related to the reconstructed environmental parameters ...
Sabrina Hohmann   +2 more
openaire   +4 more sources

Late Eocene to Early Oligocene (36–26 Ma) Rock Magnetism and Magnetostratigraphy of IODP Site U1553, Southwestern Pacific: Defying the Challenges of Carbonate Dilution and Reductive Diagenesis

open access: yesGeochemistry, Geophysics, Geosystems, Volume 27, Issue 4, April 2026.
Abstract The late Eocene to early Oligocene is an intriguing Paleogene period in which the Earth climate state changed from Warmhouse to Coolhouse. Accurate age models are essential for investigating these climate transitions. The southwestern Pacific International Ocean Discovery Program (IODP) Site U1553, with its almost complete succession of the ...
Yang Zhang   +5 more
wiley   +1 more source

Trophic Changes off Southwest Greenland During the Holocene and Their Influence on Carbon Burial

open access: yesGeophysical Research Letters, Volume 53, Issue 6, 28 March 2026.
Abstract Organic carbon (OC) burial in sediments is partly controlled by catabolic biodegradation and remineralization by heterotrophic bacteria, but long‐term records of these bacterially‐mediated processes have not been available. Here, we use stable hydrogen isotope ratio of the saturated C16 fatty acid (δ2HC16:0) as a proxy of the prevalence of ...
Estelle Allan   +6 more
wiley   +1 more source

Palynostratigraphy of the Sanganeh Formation at the East and Central Kopeh-Dagh Basin based on dinoflagellate cysts [PDF]

open access: yesJournal of Stratigraphy and Sedimentology Researches, 2015
The Sanganeh Formation (Lower Cretaceous) has cropped out across the Kopeh-Dagh Basin. The formation conformably overly the Aptian Sarcheshmeh Formation and is in turn overlain conformably by glauconitic sandstone of the Aitamir Formation. The considered
Ebrahim Ghasemi-Nejad   +2 more
doaj   +2 more sources

Palaeoenvironmental changes based on foraminifera during the late Holocene at the Beagle Channel, Argentina

open access: yesAnais da Academia Brasileira de Ciências, 2022
A foraminiferal faunal study was carried out in a Holocene marine section from Arroyo Baliza, located on the northwest coast of the Beagle Channel, to contribute to the knowledge of the palaeoenvironmental conditions during the marine Holocene event ...
EMILIANA BERNASCONI   +2 more
doaj   +1 more source

Seismic Stratigraphy of Eocene–Recent Mixed Depositional Systems on the SE New Zealand Continental Margin, Great South Basin

open access: yesNew Zealand Journal of Geology and Geophysics, Volume 69, Issue 1, March 2026.
The continental margin of SE New Zealand is strongly influenced by the Southland Current and associated water masses. This new seismic stratigraphic study of the margin has revealed a range of depositional mounds and erosional channels that document the close interaction of turbidity and bottom currents in shaping the margin from the Mid‐Eocene onward.
Onyekachi N. Ibezim   +3 more
wiley   +1 more source

Terrestrial Ecosystem Response to Changing Temperature and Seasonality in the Paleocene‐Eocene Thermal Maximum: Shallow Marine Records From the Salisbury Embayment, USA

open access: yesPaleoceanography and Paleoclimatology, Volume 41, Issue 3, March 2026.
Abstract The Paleocene‐Eocene thermal maximum (PETM, ∼56 Ma) is marked by a massive and rapid rise in atmospheric CO2 and ∼5°C of global warming. It is globally characterized by a negative carbon isotope excursion (CIE), and, at least locally, is preceded by a pre‐onset excursion (POE).
Debra A. Willard   +6 more
wiley   +1 more source

Sequence stratigraphical and palaeoenvironmental implications of Cenomanian–Santonian dinocyst assemblages from the Trans‐Sahara epicontinental seaway: a multivariate statistical approach

open access: yesThe Depositional Record
The Cretaceous was punctuated by episodic flooding of continental margins forming epicontinental seas. The Trans‐Sahara Seaway was one of these epicontinental seas, connecting the Gulf of Guinea with the Tethys Ocean.
Musa B. Usman   +3 more
doaj   +1 more source

Cretaceous and Cenozoic dinoflagellate cysts and other palynomorphs from the western and eastern margins of the Labrador–Baffin Seaway [PDF]

open access: yesGeological Survey of Denmark and Greenland Bulletin, 2016
New palynological analysis of samples from 13 offshore wells on the Canadian Margin and six wells on the West Greenland Margin has led to a new event biostratigraphic framework for Cretaceous–Cenozoic strata of the Labrador Sea – Davis Strait – Baffin ...
Robert A. Fensome   +2 more
doaj  

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