Results 81 to 90 of about 148,265 (366)

Surface chemistry of weathered zircons

Chemical Geology, 2001
We have investigated the surface morphology and chemistry of zircon in sediments and soils of the Amazon basin (Brazil). The extent of metamictization in the near-surface region of these zircons was previously determined by Raman micro-probe. Scanning electron microscopy (SEM) reveals scarce dissolution features and numerous marks related to the ...
Balan, Etienne, Trocellier, Patrick, Jupille, Jacques, Fritsch, Emmanuel, Muller, Jean-Pierre, Calas, Georges   +5 more
openaire   +4 more sources

Evidence of Enriched, Hadean Mantle Reservoir from 4.2-4.0 Ga zircon xenocrysts from Paleoarchean TTGs of the Singhbhum Craton, Eastern India

Scientific Reports, 2018
Sensitive High-Resolution Ion Microprobe (SHRIMP) U-Pb analyses of zircons from Paleoarchean (~3.4 Ga) tonalite-gneiss called the Older Metamorphic Tonalitic Gneiss (OMTG) from the Champua area of the Singhbhum Craton, India, reveal 4.24-4.03 Ga ...
T. Chaudhuri, Y. Wan, Rajat Mazumder, M. Ma, Dunyi Liu   +4 more
semanticscholar   +1 more source

High‐Titanium Zircon Rims in Rhyolite – A Reflection of Adiabatic Ascent?

Geological Journal, EarlyView.
The ascent of granitic magma from source to emplacement is rapidly achieved through dyking, resulting in negligible heat loss to the surrounding wallrock (i.e., adiabatic). Zircon growth during ascent can record the changing magma conditions including adiabatic cooling and heating, resulting in high titanium rims on low titanium cores without ...
Carson Kinney, Holden Little, Chris Yakymchuk   +2 more
wiley   +1 more source

SINTERING OF ZIRCON POWDERS

Le Journal de Physique Colloques, 1986
The study of the sintering of fine zircon powders shows that the dissociated material (SiO2 + ZrO2) densifies more rapidly than the recombined material (ZrSiO4) and that ferric oxide (Fe2O3) is an effective activator for both densification and recombination.
G. Kapelski, P. Boch
openaire   +3 more sources

Origins of the Pangkaimen Au Deposit in the Northern Great Xing'an Range, China: Evidence From Geochronological, Geochemical, Fluid Inclusion, and H–O–S–Pb Isotope Data

Geological Journal, EarlyView.
The Pangkaimen Au–Ag deposits belong to the epithermal Au deposits, which are of great significance for guiding the research and development of this type of gold deposit. Metallogenic model diagram of Pangkaimen Au–Ag deposit. ABSTRACT The gold (Au) metallogenic belt in the northern Great Xing'an Range is characterised by the wide occurrence of the ...
Sheng Lu, Hongpeng Chen, Chenglu Li, Ye Wang, Tiesheng Li, Rigen Wu, Zengtao Li, Zhichao Song, Xiannan Zhu   +8 more
wiley   +1 more source

Long story encrypted in a small grain – zircon from meta-andesite in the Lower Köli Nappes reveals a complex history of the Virisen Arc Terrane, Scandinavian Caledonides, Sweden

Mineralogia
This short report presents the investigation results on the zircon from meta-andesitic rock from the Ankarede Volcanite Formation of the Lower Köli Nappe Complex in Scandinavian Caledonides. Previous U-Pb dating revealed a wide span of dates ranging from
Walczak Katarzyna A., Włodek Adam, Cuthbert Simon, Carter Isabel S. M., Ziemniak Grzegorz   +4 more
doaj   +1 more source

Shoshonitic enclaves in the high Sr/Y Nyemo pluton, southern Tibet: Implications for Oligocene magma mixing and the onset of extension of the southern Lhasa terrane [PDF]

, 2020
Post-collisional potassic and high Sr/Y magmatism in the Lhasa terrane provides critical constraints on the timing and mechanism of subduction of Indian lithosphere and its role in the uplift of the Tibetan Plateau.
Asimow, Paul D., Liu, Dong, Mo, Xuanxue, Sheikh, Lawangin, Wang, Qing, Wang, Zhenzhen, Zhang, Liangliang, Zhao, Zhidan, Zhu, Di-Cheng   +8 more
core  

Mesozoic-Cenozoic mafic magmatism in Sanandaj-Sirjan Zone, Zagros Orogen (Western Iran): geochemical and isotopic inferences from Middle Jurassic and Late Eocene gabbros [PDF]

, 2017
One of the consequences of Neo-Tethys ocean subduction beneath the Central Iranian Micro-continent (CIMC) is the development of rare gabbroic intrusions in the Malayer-Boroujerd Plutonic Complex (MBPC) located in the Sanandaj-Sirjan Zone (SaSZ) of the ...
Deevsalar, Reza, Ghaderi, Majid, Hoskin, P.W.O., Lee, Hao Yang, Murata, Mamoru, Neill, Iain, Oshiro, Shoma, Shinjo, Ryuichi, Wang, Kuo-Lung   +8 more
core   +1 more source

Evidence From Microscopy and U–Pb Geochronology as a Clue to the Influence of the Cretaceous Magmatism in the Diagenesis of Pre‐Salt Carbonate Reservoirs in the Santos Basin (Brazil)

Geological Journal, EarlyView.
Carbonates from Santos Basin revealed U–Pb ages correlated with basalt ages (A), suggesting that they were formed during magmatic events. These events placed hot CO2 in the reservoir, which, when mixed with carbonate‐rich cold water (B), led to thermal convection, enabling the formation of the U contained in the carbonates.
Marco António Ruivo de Castro e Brito, Cristiano Leite Sombra, Davy Raeder Brandão, Cleverson Guizan Silva, Sidney Luiz de Matos Mello, Eugênio Vaz dos Santos Neto, Rui Jorge Fernandes Baptista, Ramsés Capilla, Luiz Antônio Pierantoni Gambôa   +8 more
wiley   +1 more source

Thermal history of the early Miocene Waitemata Basin and adjacent Waipapa Group, North Island, New Zealand [PDF]

, 1999
Apatite fission track (AFT) and vitrinite reflectance (VR) data for early Miocene outcrops from the Waitemata Basin reveal that the basin sequence was subjected to shallow burial before denudation.
Balance, Peter F., Brown, Roderick W., Hill, Kevin C., Kamp, Peter J.J., Raza, Asaf   +4 more
core   +2 more sources