Results 61 to 70 of about 191 (177)

Solid Inclusions in Au-nuggets, genesis and derivation from alkaline rocks of the Guli Massif, Northern Siberia

Open Geosciences, 2016
A total of 112 Au-nuggets, collected from alluvial placer deposits of the Ingarinda River from the Guli massif, located in northem Siberia, Russia, were investigated.
Dvorani Sami N.
doaj   +1 more source

Geochemistry of podiform chromitite and host rocks within the Buem Structural Unit, Northwestern Benin Republic: Implications for the geodynamic evolution of the Dahomeyide orogenic belt

Results in Earth Sciences
The paper presents the geochemistry, origin and geodynamic setting of podiform chromitite and host rocks from the Buem Structural Unit (BSU) in the northwestern Benin Republic.
Daniel N. Kouagou N’Dah, Samuel B. Olobaniyi, Luc C. Adissin Glodji, Sory I.M. Konate, Elhadji Mory Traore, Daniel Kwayisi, Clement B. N’Satta, Ibrahim S. Yerima   +7 more
doaj   +1 more source

Multi‐geophysical methods for characterizing fractures in an open pit mine, western Bushveld Complex, South Africa

Geophysical Prospecting, Volume 72, Issue 5, Page 1950-1970, June 2024.
Abstract In the Bushveld Complex, South Africa, open pit mines are faced with a challenge of rock slope stability due to geological structures (fractures, faults and dykes) that compartmentalize the rock mass. Geophysical surveys (seismics, magnetics and electrical methods) were conducted in a 0.2 km2 area at Tharisa mine, with the goal to delineate ...
Moyagabo K. Rapetsoa, Sikelela Gomo, Musa S. D. Manzi, Ian James, Jureya Dildar, Mpofana Sihoyiya, Ndamulelo Mutshafa, Raymond J. Durrheim   +7 more
wiley   +1 more source

Probing the 186Os/188Os Precision Barrier: New Recommended Values for the DROsS Reference Material and an Assessment of Mixed 1011 and 1012 Ω Amplifier Arrays

Geostandards and Geoanalytical Research, Volume 48, Issue 1, Page 109-132, March 2024.
Key Points Most precise 184Os/188Os ratio yet measured: 0.0013036 ± 0.0000007. New recommended values for DROsS: 186Os/188Os = 0.1199319 ± 0.0000024, 187Os/188Os = 0.1609227 ± 0.0000022, 189Os/188Os = 1.219709 ± 0.000010, 190Os/188Os = 1.983793 ± 0.000011.
Pedro Waterton, Sarah Woodland, Graham Pearson, Simon Hansen Serre, Kristoffer Szilas   +4 more
wiley   +1 more source

A revised map of volcanic units in the Oman ophiolite: insights into the architecture of an oceanic proto-arc volcanic sequence [PDF]

Solid Earth, 2019
Numerous studies have revealed genetic similarities between Tethyan ophiolites and oceanic “proto-arc” sequences formed above nascent subduction zones. The Semail ophiolite (Oman–U.A.E.) in particular can be viewed as an analogue for this proto-arc crust.
T. M. Belgrano, L. W. Diamond, Y. Vogt, A. R. Biedermann, A. R. Biedermann, S. A. Gilgen, K. Al-Tobi   +6 more
doaj   +1 more source

Exhumed Serpentinites and Their Tectonic Significance in Non‐Collisional Orogens

Geochemistry, Geophysics, Geosystems, Volume 25, Issue 2, February 2024.
Abstract Exhumed serpentinites are fragments of ancient oceanic lithosphere or mantle wedge that record deep fluid‐rock interactions and metasomatic processes. While common in suture zones after closure of ocean basins, in non‐collisional orogens their origin and tectonic significance are not fully understood.
Damián Donoso‐Tapia, Kennet E. Flores, Celine Martin, Esteban Gazel, Jeffrey Marsh   +4 more
wiley   +1 more source

Conversion of low-pressure chromitites to ultrahigh-pressure chromitites by deep recycling: A good inference

Earth and Planetary Science Letters, 2013
AbstractPodiform chromitites have been interpreted as a peridotite/melt reaction product within the upper mantle (= low-P chromitites). Some of them, however, contain ultrahigh-pressure (UHP) minerals such as diamond and coesite (= UHP chromitites). The UHP chromitites can be produced by deep recycling of low-P chromitites via mantle convection. Carbon-
openaire   +1 more source

PETROLOGICAL EVIDENCES OF SYNDEFORMATION SEGREGATION OF CHROMITES DURING DUNITE FORMATION: EXAMPLE OF KRAKA OPHIOLITES, SOUTH URALS [PDF]

Минералогия, 2016
Results of structural and mineralogical studies of chromitite-bearing zone localized in spinel peridotites of the Middle Kraka ophiolite massif are presented.
D.E. Saveliev, E.V. Belogub, I.A. Blinov, D.A. Kozhevnikov, V.A. Kotlyarov   +4 more
doaj  

A shallow origin for diamonds in ophiolitic chromitites

Geology, 2018
Recent findings of diamonds in ophiolitic peridotites and chromitites challenge our traditional notion of Earth mantle dynamics. Models attempting to explain these findings involve incorporation of diamonds into chromite near the mantle transition zone. However, the occurrence of metastable diamonds in this context has not been considered.
Farré-de-Pablo, Júlia, Proenza, Joaquín A., González-Jiménez, José María, Garcia-Casco, Antonio, Colás, Vanessa, Roqué-Rossell, Josep, Camprubí, Antoni, Sánchez-Navas, Antonio   +7 more
openaire   +3 more sources

Hydrated Peridotite–Basaltic Melt Interaction Part II: Fast Assimilation of Serpentinized Mantle by Basaltic Magma

Frontiers in Earth Science, 2020
The most abundant terrestrial lavas, mid-ocean ridge basalt (MORB) and ocean island basalt (OIB), are commonly considered to be derived from a depleted MORB-mantle component (DMM) and more specific, variably enriched mantle plume sources.
Anastassia Y. Borisova, Anastassia Y. Borisova, Nail R. Zagrtdenov, Michael J. Toplis, Georges Ceuleneer, Oleg G. Safonov, Oleg G. Safonov, Oleg G. Safonov, Gleb S. Pokrovski, Klaus Peter Jochum, Brigitte Stoll, Ulrike Weis, Svyatoslav Shcheka, Andrey Y. Bychkov   +13 more
doaj   +1 more source