Results 51 to 60 of about 457 (183)

Minimal Perturbation of the Global Mercury Cycle by the Paraná–Etendeka Large Igneous Province (PE–LIP) During the Onset of the Valanginian Weissert Event

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 7, July 2026.
Abstract The Valanginian positive carbon isotope excursion (Weissert Event, ca. 135 million years ago) documents a major global carbon cycle and climate perturbation. Radioisotopic dating suggests that this event was broadly contemporaneous with an interval of profoundly enhanced volcanic activity during the emplacement of the Paraná–Etendeka Large ...
K. Krishnaswamy, J. Frieling, L. M. E. Percival, K. Littler, S. Reboulet, I. M. Fendley, T. A. Mather, S. A. Robinson   +7 more
wiley   +1 more source

Integrated biostratigraphy of two Upper Maastrichtian – Palaeocene successions in north-central Sinai, Egypt

Geologia Croatica, 2012
Integration of the calcareous nannofossil and planktonic foraminiferal biostratigraphies has been performed for theUpper Maastrichtian – Palaeocene successions at Gebel Umm Khushayb and west El-Hassana sections (north-centralSinai, Egypt).
Mahmoud Faris, Sherif Farouk
doaj   +1 more source

Biostratigraphy of Gurpi Formation in Samand anticline (Lurestan province) Based on calcareous nannofossils [PDF]

Journal of Stratigraphy and Sedimentology Researches, 2017
The present study is an attempt to biostratigraphically classify the rocks of Gurpi Formation at Samand Anticline with the help of calcareous nannofossils. The succession measures 197 meters in thickness and consists of shale, marl and marly limestone. A
samira shahriyary, Anoshiravan Kani, Hassan Amiribakhtiar   +2 more
doaj   +1 more source

Osmium Isotope and Highly Siderophile Element Constraints on the Cretaceous/Paleogene Boundary in Western Pacific Pelagic Clay

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 7, July 2026.
Abstract The Cretaceous/Paleogene (K/Pg) Chicxulub impact produced globally synchronous enrichments of highly siderophile elements (HSEs) and a pronounced decline in marine osmium isotope ratios (187Os/188Os), forming a key geochemical marker of the boundary.
Honami Sato, Yoichi Usui, Kazuhide Mimura, Akira Ishikawa, Kazutaka Yasukawa, Junichiro Ohta, Yasuhiro Kato   +6 more
wiley   +1 more source

Commentary: Reframing Massive Carbon Input During the PETM and a Grand 66 Million Year Geoscience Puzzle

Geophysical Research Letters, Volume 53, Issue 12, 28 June 2026.
Abstract Despite decades of research, hundreds of peer‐reviewed papers, and considerable relevance to Earth's future, the rapid global warming and tremendous CO2 input at the start of the Paleocene‐Eocene Thermal Maximum (PETM) remain highly debated.
Gerald R. Dickens
wiley   +1 more source

A REVISED METHOD FOR OBSERVING THE SAME NANNOFOSSIL SPECIMENS WITH SCANNING ELECTRON MICROSCOPE AND LIGHT MICROSCOPE

Rivista Italiana di Paleontologia e Stratigrafia, 2018
A new method for the observation of the same nannofossil specimens with scanning electron microscope and light microscope, involving the use of a grid, is described.
C. PIRINI RADRIZZANI, D. CASTRADORI, E. ERBA, G. GUASTI, A. RIZZI   +4 more
doaj   +1 more source

Holocene Slip Behavior and Shallow Structure of the Milun Fault at the Collision–Subduction Transition, Eastern Taiwan

New Zealand Journal of Geology and Geophysics, Volume 69, Issue 2, June 2026.
The Milun Fault forms the northernmost onshore segment of the Longitudinal Valley fault system, a plate‐boundary suture between the Eurasian and Philippine Sea plates in eastern Taiwan, and poses a significant seismic hazard to Hualien City. Despite destructive earthquakes in 1951 and 2018, the shallow structure, long‐term slip behavior, and ...
Wen‐Jeng Huang, Ya‐Chu Tseng, Wen‐Shan Chen, I‐Chin Yen, Shao‐Yi Huang, Jiun‐Yee Yen, Shih‐Ting Lu   +6 more
wiley   +1 more source

CALIBRATION OF THE PLIENSBACHIAN-TOARCIAN CALCAREOUS NANNOFOSSIL ZONE BOUNDARIES BASED ON AMMONITES (BASQUE-CANTABRIAN AREA, SPAIN)

Rivista Italiana di Paleontologia e Stratigrafia, 2004
Based on a continuous succession of ammonite and calcareous nannofossil assemblages, the main purpose of this paper is the correlation between ammonite and calcareous nannofossil zone boundaries in two expanded sections from the Basque-Cantabrian area ...
NICOLA PERILLI, MARÍA JOSÉ COMAS-RENGIFO, ANTONIO GOY   +2 more
doaj   +1 more source

New Insights Into Hikurangi Subduction Inputs and Megathrust Host Rocks Spanning Along‐Margin Changes in Fault Slip Behavior

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 6, June 2026.
Abstract The seismic behavior of subduction megathrusts varies spatially and is influenced by the properties of subducting plates, including their sedimentary cover. Characterizing these subduction inputs is essential for understanding the mechanisms behind fault slip variability.
Philip M. Barnes, Gareth J. Crutchley, Martin P. Crundwell, Stuart A. Henrys, Andrew Gase, Sam R. Davidson, Nathan Bangs, Harm Van Avendonk, Michael Underwood, Anthony E. Shorrock, Laura S. McDonald, Lorna J. Strachan, Helen C. Bostock   +12 more
wiley   +1 more source

Calcareous nannofossils and Mesozoic oceanic anoxic events

Marine Micropaleontology, 2004
Abstract Twenty-five years ago, Mesozoic oceanic anoxic events (OAEs) were documented and formalised as intervals of widespread to global deposition of organic matter. The Toarcian, Early Aptian (OAE1a) and latest Cenomanian (OAE2) OAEs are truly global in nature, commonly carbonate-poor, and typically represented by organic carbon-rich black shales.
openaire   +1 more source