Results 51 to 60 of about 849 (144)

Compositional Zoning in Amphibole from Amphibole Bearing Parageneses of West Psunj (Croatia): Evidence for Progressive Metamorphism?

Geologia Croatica, 2010
Amphibole bearing parageneses from the western part of Mt. Psunj (Croatia) record evidence of prograding metamorphism. Opticaland microprobe analyses, together with thermobarornetric evaluationson amphibole bearing parageneses, show a zonation with Si ...
Dražen Balen, Vladimir Bermanec, Vera Marci   +2 more
doaj   +1 more source

Identification and correlation of the Aso‐3 tephra in the Omaezaki area, central Japan: A valuable key stratum for the MIS 6/5 transition period

Journal of Quaternary Science, Volume 41, Issue 6, Page 972-986, August 2026.
ABSTRACT The Aso‐3 tephra is one of the most significant widespread marker layers from the Middle to Late Pleistocene, generated by a large caldera‐forming eruption at the Aso volcano in Kyushu, southwestern Japan. Despite its importance, a distal co‐ignimbrite ash correlative has yet to be clearly identified, primarily because although volcanic glass ...
Toshinori Sasaki, Takuya Morimoto, Tatsuyuki Ueno, Kazuo Mizoguchi, Norihisa Goto, Hisanori Ominami, Shohei Onaka   +6 more
wiley   +1 more source

Petrogenesis and Tectonic Evolution of Cenozoic Magmatism in the Southernmost Northern Andes: Insights From Zircon Petrochronology

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 8, August 2026.
Abstract This study integrates new zircon U–Pb ages, zircon εHf(t)–δ18O isotopic data, and whole‐rock geochemistry to refine the temporal and spatial framework of magmatism in the southern Northern Andes (SNA) from ∼65 to 6 Ma. The San Lucas, Catamayo, Portachuela, and Gonzanamá batholiths and magmatic suites, along with Late Miocene plutons, display ...
J. Iglesias, C. Witt, L. C. Sandoval Espinel, M. Zattin, M. Poujol, O. Bruguier, O. Poma, M. J. Hernández, O. Averbuch, M. Seyler, D. Bosch, F. Chanier, S. Ventalon, C. Liorzou, V. Bosse   +14 more
wiley   +1 more source

Crustal Thickness Inversion From Magmatic Geochemistry Reveals Spatiotemporal Evolution and Two‐Stage Uplift of the Iranian Plateau

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 8, August 2026.
Abstract The Cenozoic topographic growth of the Iranian Plateau, situated at the Arabia‐Eurasia collision front, provides insights into continental collision dynamics. However, the relative contributions of tectonic shortening versus deep mantle processes to crustal thickening remain debated because systematic quantitative constraints on paleo‐crustal ...
Jun Hu, Yongwei Zhao, Zhengquan Chen, Ni Li, Huan Kang   +4 more
wiley   +1 more source

Oxygen Fugacity Buffers and an Interactive Calculator

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 8, August 2026.
Abstract Oxygen fugacity buffers are equilibrium phase assemblages that constrain the chemical potential of oxygen. They may be coexisting minerals or fluids, or their metastable extrapolations. Oxygen fugacity values vary as a function of pressure and temperature, such that raw numbers often have little interpretive value.
Michael Anenburg
wiley   +1 more source

Highly Enriched and Heterogeneous Mantle Signals Recorded in Mantle Pyroxenite Veins

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 8, August 2026.
Abstract The Earth's mantle is inherently heterogeneous, reflecting ongoing mantle depletion and crustal recycling driven by plate tectonics. Radiogenic isotopes in oceanic basalts are commonly used to characterize mantle reservoirs, but the full chemical diversity of mantle‐derived melts may be obscured by magma mixing during melt transport and ...
Zhen‐Yu Zhang, Chuan‐Zhou Liu, Yan Liang, Tong Liu, Chang Zhang, Bo‐Da Liu, Wen‐Bin Ji, Wei‐Qi Zhang, Ke Huang   +8 more
wiley   +1 more source

Negative Frictional Healing in Icelandic Geothermal (IDDP‐2) Core Samples: Potential Implications for Detachment‐Fault Mechanics

Geochemistry, Geophysics, Geosystems
Detachment faults in mid‐ocean ridge settings accommodate tectonic extension. These faults are potentially weakened by alteration through phyllosilicate‐ and amphibole‐mineral formation.
Barnaby Fryer, Florian Jermann, Patricia Patrier, Bruno Lanson, Stanislav Jelavic, Simon Guérin‐Marthe, Gabriel Meyer, Fabrice Barou, Marie Violay   +8 more
doaj   +1 more source

Kôzulite, an Mn-rich alkali amphibole

Acta Crystallographica Section E, 2010
The crystal structure of kôzulite, an Mn-rich alkali amphibole with the ideal formula NaNa2[Mn42+(Fe3+,Al)]Si8O22(OH)2, trisodium tetramanganese iron/aluminium octasilicate dihydroxide, was refined from a natural specimen with composition (K0 ...
Madison C. Barkley, Robert T. Downs, Hexiong Yang   +2 more
doaj   +1 more source

Minerals in Iron and Titanium Skeletal Textures in Nakhlites MIL 090030, MIL 090136, MIL 090032, and MIL 03346: Comparative Analysis With Terrestrial Analogues From Canary Islands, Spain

Journal of Geophysical Research: Planets, Volume 131, Issue 8, August 2026.
Abstract The presence of minor minerals is a key factor distinguishing meteorite types, as they provide valuable insights into the formation processes, surface conditions, and evolutionary history of their parent bodies. In Martian nakhlites, one of the most distinctive minor phases is iron‐titanium oxides forming characteristic skeletal textures ...
Leire Coloma, Fernando Alberquilla, Julene Aramendia, Gorka Arana, Ed Cloutis, Juan Manuel Madariaga   +5 more
wiley   +1 more source

Amphibole's Influence on Mid‐Lithosphere Discontinuity: Insights From Electrical Conductivity

Geophysical Research Letters
The potential role of metasomatism‐induced hydrated layers, such as amphibole, in causing the mid‐lithospheric discontinuities (MLDs) has been widely debated.
Kewei Shen, Duojun Wang, Rui Zhang, Guangchao Chen, Kenan Han, Peng Chen, Ruixin Zhang, Zhiqing Zhang   +7 more
doaj   +1 more source