Results 61 to 70 of about 17,487 (279)

Geochemical and Geological Investigation of Skarn‐Type Pb–Zn Mineralization in Hastanetepe (Balya‐Balıkesir, Türkiye): An Approach Based on Fluid Inclusions, Sulphur Isotopes and Geochemical Data

Geological Journal, EarlyView.
Integrated petrographic, mineralogical and geochemical data from the Hastanetepe Pb–Zn deposit (Balya, Türkiye) reveal multi‐stage hydrothermal alteration and a magmatic sulphur source. Fluid inclusion and sulphur isotope results indicate a complex fluid evolution responsible for skarn‐type Pb–Zn mineralization along limestone–dacite contacts ...
Esra Ünal‐Çakır
wiley   +1 more source

Geochemical variation at the Hawaiian hot spot caused by upper mantle dynamics and melting of a heterogeneous plume

Geochemistry, Geophysics, Geosystems, 2008
Geochemical variations within the young Hawaiian Islands occur in two particularly prominent forms: differences between volcanic stages and differences between the “Loa” and “Kea” subchains.
Todd Anthony Bianco, Garrett Ito, Jeroen van Hunen, Maxim D. Ballmer, John J. Mahoney   +4 more
doaj   +1 more source

Do Olivine Crystallization Temperatures Faithfully Record Mantle Temperature Variability?

Geochemistry, Geophysics, Geosystems, 2021
Crystallization temperatures of primitive olivine crystals have been widely used as both a proxy for, or an intermediate step in calculating, mantle temperatures. The olivine‐spinel aluminum‐exchange thermometer has been applied to samples from mid‐ocean
Simon Matthews, Kevin Wong, Oliver Shorttle, Marie Edmonds, John Maclennan   +4 more
doaj   +1 more source

Geochemistry and Geochronology of Magmatic Rocks in Southwestern and Northeastern Cambodia: Implications for the Tectonic Evolution and Metallogenesis of the Loei Fold Belt

Geological Journal, EarlyView.
The composition of intrusive rocks suggests that the magma was likely generated in a subduction‐related setting. The arc crustal thickness in the Phnom Sro Ngam and Halo Prospects was probably < 40 km during emplacement. Zircon U–Pb age range indicates a correlation with Loei Fold Belt magmatic activity.
Sirisokha Seang, Khin Zaw, Kakda Kret, Ivan Belousov, Kotaro Yonezu, Koichiro Watanabe, Charles Makoundi   +6 more
wiley   +1 more source

Deglaciation-enhanced mantle CO2 fluxes at Yellowstone imply positive climate feedback

Nature Communications
Mantle melt generation in response to glacial unloading has been linked to enhanced magmatic volatile release in Iceland and global eruptive records. It is unclear whether this process is important in systems lacking evidence of enhanced eruptions.
Fiona Clerc, Mark D. Behn, Brent M. Minchew   +2 more
doaj   +1 more source

The latest geodynamics in Central Asia: primary and secondary mantle melting anomalies in the context of orogenesis, rifting, and lithospheric plate motions and interactions

Геодинамика и тектонофизика, 2017
A comprehensive model for deep dynamics in Asia has been developed from the data on the evolution of melting anomalies in the context of lithospheric plate motions, interactions, orogeny, and rifting.
I. S. Chuvashova, S. V. Rasskazov, Sun Yi-min   +2 more
doaj   +1 more source

Late Pleistocene Volcanic Rocks From Tengchong Volcanic Field at SE Tibetan Plateau: Constraints on Petrogenesis and Mantle and Crustal Processes

Geological Journal, EarlyView.
Early zircon saturation and crystallisation occur in mafic (52–54 wt.% SiO2) lavas at Tengchong volcanic field. These early formed zircons with high δ18O (6.6‰–7.9‰) indicates mantle enrichment by subducted supracrustal materials. ABSTRACT Late Pleistocene (< 0.2 Ma) mafic and evolved volcanic rocks occur in northern Tengchong Volcanic Field, SE ...
Lizhu Wang, Haibo Zou
wiley   +1 more source

Deglaciation of the Burren glacio‐karst, western Ireland, during Termination 1: Implications for North Atlantic climate and karstification

Journal of Quaternary Science, EarlyView.
Abstract The Burren uplands in western Ireland form one of the most extensive and best‐preserved examples of glacio‐karst in Europe. Subsumed by the Irish ice sheet during the Late Pleistocene, granite erratic boulders and in situ silica veins in the limestone bedrock provide a rare opportunity to reconstruct the timing and rate of deglaciation ...
Gordon Bromley, Colin Bunce, Brenda Hall, Aaron Putnam, Frank McDermott   +4 more
wiley   +1 more source

The constant oxidation state of Earth’s mantle since the Hadean

Nature Communications
Determining the evolutionary history of mantle oxygen fugacity (fo2) is crucial, as it controls the fo2 of mantle-derived melts and regulates atmospheric composition through volcanic outgassing. However, the evolution of mantle fo2 remains controversial.
Fangyi Zhang, Vincenzo Stagno, Lipeng Zhang, Chen Chen, Haiyang Liu, Congying Li, Weidong Sun   +6 more
doaj   +1 more source

Competing effects of spreading rate, crystal fractionation and source variability on Fe isotope systematics in mid-ocean ridge lavas

Scientific Reports, 2021
Two-thirds of the Earth is covered by mid-ocean ridge basalts, which form along a network of divergent plate margins. Basalts along these margins display a chemical diversity, which is consequent to a complex interplay of partial mantle melting in the ...
Marianne Richter, Oliver Nebel, Martin Schwindinger, Yona Nebel-Jacobsen, Henry J. B. Dick   +4 more
doaj   +1 more source