Results 1 to 10 of about 90,092 (222)

Olivine zoning and retrograde olivine-orthopyroxene-metal equilibration in H5 and H6 chondrites [PDF]

Meteoritics & Planetary Science, 2006
Electron microprobe studies of several H5 and H6 chondrites reveal that olivine crystals exhibit systematic Fe-Mg zoning near olivine-metal interfaces. Olivine Fa concentrations decrease by up to 2 mol% toward zoned taenite + kamacite particles (formed after relatively small amounts of taenite undercooling) and increase by up to 2 mol% toward zoneless ...
Reisener, RJ, Goldstein, JI, Petaev, MI
core   +3 more sources

Chemical zoning of olivine in several pallasites [PDF]

Journal of Geophysical Research, 1997
Chemical zoning profiles of olivines in the Esquel, Imilac, and Yamato 8451 pallasites were measured by using an electron probe microanalyzer in order to study their cooling histories. Pallasite olivines are considered to be compositionally uniform but show faint zoning for Fe‐Mg, CaO, Al2O3, Cr2O3, and MnO within a few hundred micrometers from the rim.
exaly   +2 more sources

Depth profile analyses by femtosecond laser ablation (multicollector) inductively coupled plasma mass spectrometry for resolving chemical and isotopic gradients in minerals [PDF]

European Journal of Mineralogy, 2023
Femtosecond laser ablation (fs-LA) coupled to a multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) instrument has been proven to be a powerful means to analyze isotope ratios of “non-traditional” stable isotope systems with high ...
M. Oeser, I. Horn, R. Dohmen, S. Weyer
doaj   +1 more source

In-situ Sr isotope disequilibrium in plagioclases from Late Cenozoic basalts in Leiqiong area: Evidence for the role of the Hainan plume and mantle metasomatism due to a paleo-subduction event

Frontiers in Earth Science, 2023
The origin of the EM2 (enriched mantle 2)-type reservoir beneath the Southeast Asia is controversial. In this study, we present new in-situ major and trace element (olivine, clinopyroxene, and plagioclase), and Sr isotopic compositions (plagioclase) for ...
Shuang-Shuang Chen, Shuang-Shuang Chen, Shuang-Shuang Chen, Shuang-Shuang Chen, Duo-Yang Wu, Duo-Yang Wu, Duo-Yang Wu, Rui Gao, Rui Gao, Rui Gao, Qiuming Cheng, Qiuming Cheng, Jia-Qi Liu   +12 more
doaj   +1 more source

Automated Segmentation of Olivine Phenocrysts in a Volcanic Rock Thin Section Using a Fully Convolutional Neural Network

Frontiers in Earth Science, 2022
An example of automated characterization and interpretation of the textural and compositional characteristics of solids phases in thin sections using machine learning (ML) is presented.
Artem Leichter, Renat R. Almeev, Dennis Wittich, Philipp Beckmann, Franz Rottensteiner, Francois Holtz, Monika Sester   +6 more
doaj   +1 more source

Out-of-sequence skeletal growth causing oscillatory zoning in arc olivines [PDF]

Nature Communications, 2021
AbstractPrimitive olivines from the monogenetic cones Los Hornitos, Central-South Andes, preserve dendritic, skeletal, and polyhedral growth textures. Consecutive stages of textural maturation occur along compositional gradients where high Fo–Ni cores of polyhedral olivines (Fo92.5, Ni ~3500 ppm) contrast with the composition of dendritic olivines (Fo &
Pablo Salas, Philipp Ruprecht, Laura Hernández, Osvaldo Rabbia   +3 more
openaire   +3 more sources

Ultramafic pseudotachylytes in high-pressure metamorphogenic peridotite from Luobusha, Tibet: a record of crustal paleo-earthquakes

Frontiers in Earth Science, 2023
In this paper, we report an occurrence of ultramafic pseudotachylytes, providing fault-rock evidence of paleo-earthquakes, from the Luobusha ophiolite complex in the Yarlung Zangbo suture zone.
Haoran Zhang, Xiwei Xu, Saihong Yang
doaj   +1 more source

Phosphorus Coupling Obfuscates Lithium Geospeedometry in Olivine

Frontiers in Earth Science, 2020
Lithium zoning in zircon and olivine provides a powerful record of crystal histories and magmatic processes in volcanic systems. Characterizing Li behavior in olivine is important because it is one of the few elements in basaltic systems that track short-
Kendra J. Lynn, Michael O. Garcia, Thomas Shea   +2 more
doaj   +1 more source

Olivine friction at the base of oceanic seismogenic zones [PDF]

Journal of Geophysical Research: Solid Earth, 2007
We investigate the strength and frictional behavior of olivine aggregates at temperatures and effective confining pressures similar to those at the base of the seismogenic zone on a typical ridge transform fault. Triaxial compression tests were conducted on dry olivine powder (grain size ≤60 μm) at effective confining pressures between 50 and 300 MPa ...
Boettcher, Margaret S., Hirth, Greg, Evans, Brian   +2 more
openaire   +2 more sources

Zoned Pyroxenes as Prospectivity Indicators for Magmatic Ni-Cu Sulfide Mineralization

Frontiers in Earth Science, 2020
Small intrusions dominated by olivine- and pyroxene-rich cumulates are well known to be favorable hosts to magmatic Ni-Cu-(Platinum Group Element—PGE) sulfide mineralization.
Louise Schoneveld, Stephen J. Barnes, Hannu V. Makkonen, Margaux Le Vaillant, David J. Paterson, Valentina Taranovic, Kai-Yuan Wang, Kai-Yuan Wang, Ya-Jing Mao   +8 more
doaj   +1 more source