Results 91 to 100 of about 16,800 (234)

Investigation on primary and secondary processes in Nasirabad manganese deposit, south of Neyriz: using mineralogy and Pb isotope geochemistry

Journal of Economic Geology, 2013
The Nasirabad manganese deposit is located 5 km south of Nasirabad, 8 km SW of Neyriz in the Fars province. Structurally, the area is placed in the southeastern part of Zagros thrust belt. In this area, the manganese mineralization occurred as ore layers
Ali Reza Zarasvandi, Mohsen Rezaei, Houshang Pourkaseb, Adel Saki   +3 more
doaj  

Oceanic Anoxic Event 2 triggered by Kerguelen volcanism

Nature Communications
Large Igneous Provinces (LIPs) are associated with global warming and carbon cycle perturbations during Oceanic Anoxic Event 2 (OAE2, ~94 Ma) and the Mid-Cenomanian Event (MCE, ~96.5 Ma).
C. A. Walker-Trivett, S. Kender, K. A. Bogus, K. Littler, T. Edvardsen, M. J. Leng, J. Lacey, J. B. Riding, I. L. Millar, D. Wagner   +9 more
doaj   +1 more source

Radioactive and radiogenic isotope research

Eos, Transactions American Geophysical Union, 1971
The number of laboratories and workers in the field of radioactive isotope research has grown rapidly over the past four years. With this growth has come a large increase in the volume of literature on the subject. Consequently the bibliography, given below is meant to include the more significant or more complete investigations.
openaire   +1 more source

Slab‐Mantle Interaction During Subduction Initiation: Constraints From Trace Element and Sr‐Nd‐Pb Isotope Systematics of Boninite and Other Magmas and Metamorphic Sole in the Oman Ophiolite

Journal of Geophysical Research: Solid Earth, Volume 131, Issue 2, February 2026.
Abstract The Late Cretaceous Oman ophiolite includes a series of volcanic rocks generated during the transition from spreading ridge to protoarc associated with subduction initiation. We analyzed major and trace elements and Sr, Nd, and Pb isotope compositions of lavas and dikes of the protoarc stage, especially boninites. We also analyzed amphibolites
Tsuyoshi Ishikawa, Kazuya Nagaishi, Kyoko Kanayama, Keitaro Kitamura, Shigeyuki Wakaki, Yuki Kusano, Susumu Umino   +6 more
wiley   +1 more source

The Vazante and Canastra groups revisited: Sm-Nd and Sr isotopes - evidence for contribution from Tonian intraplate magmatism during passive margin development along the SW São Francisco margin, Brazil

Brazilian Journal of Geology, 2019
Combined Sm-Nd isotope studies and U-Pb ages of detrital zircons have shown significant differences between the provenance patterns of Neoproterozoic metasedimentary successions in the Southern Brasília belt.
Manuela de Oliveira Carvalho, Claudio de Morisson Valeriano, Carla Cristine Aguiar Neto, Gustavo Diniz Oliveira, Monica Heilbron   +4 more
doaj   +1 more source

Glacial reduction of AMOC strength and long term transition in weathering inputs into the Southern Ocean since the Mid Miocene: Evidence from radiogenic Nd and Hf isotopes [PDF]

, 2017
Combined seawater radiogenic hafnium (Hf) and neodymium (Nd) isotope compositions were extracted from bulk sediment leachates and foraminifera of Site 1088, ODP Leg 177, 2082 m water depth on the Agulhas Ridge.
Dausmann, Veit, Frank, Martin, Gutjahr, Marcus, Rickli, Jörg   +3 more
core   +1 more source

Heat and Tectonics of the Canadian Cordillera From the Seismically Constrained Inversion of Gravity Data

Tectonics, Volume 45, Issue 2, February 2026.
Abstract An updated approach to seismically constrained modeling of gravity data reveals two broad, NW‐trending low‐density zones in the mantle lithosphere beneath the Canadian Cordillera. The low‐density zones coincide with a shallow lithosphere‐asthenosphere boundary (LAB), a shallow Curie‐point depth, and the location of Quaternary volcanoes.
Nathan Hayward, Tark S. Hamilton
wiley   +1 more source

Continental Crust Rejuvenation Across the Paleo‐Mesoarchean Transition Resulted From Elevated Mantle Geotherms

Geophysical Research Letters
The increase in initial Hf isotopes identified in early Mesoarchean detrital zircon is commonly interpreted as a reflection of the geodynamic transition from stagnant‐lid to mobile‐lid tectonics.
Gui‐Mei Lu, Yi‐Gang Xu, Wei Wang, Christopher J. Spencer, Guangyu Huang, Nick M. W. Roberts   +5 more
doaj   +1 more source

Mass Spectrometry in Earth Sciences: The Precise and Accurate Measurement of Time

CHIMIA, 2014
Precise determinations of the isotopic compositions of a variety of elements is a widely applied tool in Earth sciences. Isotope ratios are used to quantify rates of geological processes that occurred during the previous 4.5 billion years, and ...
Urs Schaltegger, Jörn-Frederik Wotzlaw, Maria Ovtcharova, Massimo Chiaradia, Richard Spikings   +4 more
doaj   +1 more source

Location, Location, Location: Monazite Behaviour During UHT Metamorphism and Melt Crystallization

Journal of Metamorphic Geology, Volume 44, Issue 2, Page 158-175, February 2026.
ABSTRACT Monazite is a robust mineral for recording the suprasolidus evolution of migmatites and granulites. However, monazite commonly has diverse compositions and yields variable dates in a single sample; understanding the controls on monazite behaviour and composition during partial melting and melt crystallization are not always straightforward ...
Chris Yakymchuk, Jessica Gareau, Michael Williams   +2 more
wiley   +1 more source