Results 71 to 80 of about 72,842 (206)

Why is the remanent magnetic intensity of Cretaceous MORB so much higher than that of mid to late Cenozoic MORB? [PDF]

Geosphere, 2005
The fact that the natural remanent magnetization (NRM) intensity of mid-oceanicridge basalt (MORB) samples shows systematic variations as a function of age has long been recognized: maximum as well as average intensities are generally high for very young samples, falling off rather rapidly to less than half the recent values in samples between 10 and ...
Daming Wang, Rob Van der Voo, Donald R. Peacor   +2 more
openaire   +1 more source

Key New Evidence for the Hainan Mantle Plume Head: Ongoing Formation of a Large Igneous Province?

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 5, May 2026.
Abstract The process‐based surface magmatic expression of mantle plumes is typically a large igneous province (LIP) induced by the mantle plume head, followed by subsequent age‐progressive volcanic tracks resulting from plate drifting above the plume tail.
F. Yang, X. L. Huang, L. Liu, Y. G. Xu, Y. Hua, P. L. He, L. Zhang, W. F. Zhang, Y. Yu, H. Y. Li   +9 more
wiley   +1 more source

Primitive Cretaceous island-arc volcanic rocks in eastern Cuba: the Téneme Formation

Geologica Acta, 2006
The Téneme Formation is located in the Mayarí-Cristal ophiolitic massif and represents one of the three Cretaceous volcanic Formations established in northeastern Cuba.
J.A. PROENZA FERNÁNDEZ, R. DÍAZ-MARTÍNEZ, A. IRIONDO, C. MARCHESI, Joan-Carles Melgarejo i Draper, F. GERVILLA LINARES, C. J. GARRIDO MARÍN, A. RODRÍGUEZ VEGA, J. A. BLANCO-MORENO, R. LOZANO-SANTACRUZ   +9 more
doaj   +1 more source

Chemical Geodynamics of Granitoid Magmatism During a Pacific‐Philippine Sea Plate Transition in Southwest Japan

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 5, May 2026.
Abstract Granitoid magmatism along the western Pacific margin records interactions between subduction dynamics and crust–mantle processes; however, the links between plate reorganization and magma‐source evolution remain debated. Here we integrate U–Pb zircon geochronology with Pb–Sr–Nd–Hf isotope systematics to investigate Cretaceous–Paleogene ...
Nghiem V. Dao, Tsegereda A. Yemer, Tulibako T. Mwaisuba, Chie Sakaguchi, Hiroshi Kitagawa, Katsura Kobayashi, Teruyoshi Imaoka, Eizo Nakamura   +7 more
wiley   +1 more source

Constraints on Noble Gas Variability in OIB and MORB From Non‐Equilibrium Magmatic Degassing Models

Geochemistry, Geophysics, Geosystems
Noble gas concentrations in ocean island basalts (OIB) and mid‐ocean ridge basalts (MORB) are affected by degassing processes, obscuring their pre‐eruptive characteristics.
Thomas Williams, Stephen Parman, Christian Huber   +2 more
doaj   +1 more source

Trace element geochemistry of peridotites from the Izu-Bonin-Mariana Forearc, Leg 125

, 1992
Trace element analyses (first-series transition elements, Ti, Rb, Sr, Zr, Y, Nb, and REE) were carried out on whole rocks and minerals from 10 peridotite samples from both Conical Seamount in the Mariana forearc and Torishima Forearc Seamount in the Izu ...
Ingram, G., Johnson, K. T. M., Parkinson, I. J., Pearce, J. A., Thirlwall, M. F.   +4 more
core   +1 more source

Brillouin Scattering Observations of Elastic Behavior Across the Post‐Stishovite Transition Under Deviatoric Stress in Polycrystalline Al‐Bearing Stishovite

Journal of Geophysical Research: Solid Earth, Volume 131, Issue 5, May 2026.
Abstract Stishovite (SiO2), a key phase in subducted mid‐ocean ridge basalt (MORB), undergoes a ferroelastic transition to a CaCl2‐type structure, potentially explaining localized shear wave velocity (VS) anomalies in the shallow to mid‐lower mantle. However, the phase boundary determining this transition remains debated.
Ewa Krymarys, Motohiko Murakami, Pinku Saha, Christian Liebske, Julien Allaz, Koutaro Hikosaka, Kenji Ohta   +6 more
wiley   +1 more source

Al2O3 in Anorthositic Slabs: A New Perspective on LLSVPs and Seismic Velocity Variations

Geophysical Research Letters, Volume 53, Issue 8, 28 April 2026.
Abstract Aluminum is a key component of crustal and mantle minerals, influencing melting and geochemical evolution within the Earth. Al2O3 exists as corundum at the surface and in upper mantle conditions, but transforms into high‐pressure phases like Rh2O3(II) at lower mantle depths, enabling stability over a wide pressure range.
Ishita Das, Vincent Adongo, Gaurav Shukla   +2 more
wiley   +1 more source

Evidence of the spreading culmination in the Eastern Tethyan Repno oceanic domain, assessed by the petrology and geochemistry of N-MORB extrusive rocks from the Mt. Medvednica ophiolite mélange (NW Croatia)

Geologia Croatica, 2012
Eastern Tethyan Repno oceanic domain (ROD) from Zagorje-Mid-Transdanubian Shear Zone bounds Meliata-Maliak and Dinaric-Vardar oceanic systems. The domain lacks ophiolite complexes and oceanic rocks are restricted into Early Callovian to Late Valanginian ...
Damir Slovenec, Boško Lugović
doaj   +1 more source

Triassic MORB magmatism in the southern Mirdita zone (Albania)

, 2006
In southern Albania the Mirdita Ophiolitic nappe is characterized by subophiolitic complexes in which remnants of volcanic ophiolite sequences of Triassic age have been identified, either as rare blocks of variable dimension in the Rubik Complex, or as a thin tectonic unit (the Porava Unit), sited immediately under the main ophiolitic masses of the ...
Valerio Bortolotti, Marco Chiari, Alaudin Kodra, Marta Marcucci, Michele Marroni, Faruk Mustafa, Mensi Prela, Luca Pandolfi, Gianfranco Principi, Emilio Saccani   +9 more
openaire   +6 more sources