Results 51 to 60 of about 5,382 (223)

The nature of zircon in the Volkovsky massif gabbro (Middle Urals): the age problem and geochronological consequences

Литосфера, 2017
The article presents new isotope-geochemical data on zircon from gabbronorites of the Volkovsky massif in the Middle Urals. The massif is a complex combination of different rock associations - from ultramafic rocks to syenites and quartz diorites, whose ...
Elena V. Anikina, Artur A. Krasnobaev, Evgenii V. Pushkarev, Igor’ A. Rusin   +3 more
doaj   +1 more source

Pre-1.91 Ga deformation and metamorphism in the Palaeoproterozoic Vammala Migmatite Belt, southern Finland, and implications for Svecofennian tectonics [PDF]

Bulletin of the Geological Society of Finland, 2004
A metamorphic event in the Vammala Migmatite Belt (VMB) at ~1.92 Ga, revealed by SHRIMP U-Pb analyses of both zircon overgrowths and monazite, is interpreted as post-depositional and is correlated with the development of the early high-grade schistosity.
R.W.R. Rutland, I.S. Williams, K. Korsman   +2 more
doaj   +1 more source

Geochemistry and Geochronology of Magmatic Rocks in Southwestern and Northeastern Cambodia: Implications for the Tectonic Evolution and Metallogenesis of the Loei Fold Belt

Geological Journal, EarlyView.
The composition of intrusive rocks suggests that the magma was likely generated in a subduction‐related setting. The arc crustal thickness in the Phnom Sro Ngam and Halo Prospects was probably < 40 km during emplacement. Zircon U–Pb age range indicates a correlation with Loei Fold Belt magmatic activity.
Sirisokha Seang, Khin Zaw, Kakda Kret, Ivan Belousov, Kotaro Yonezu, Koichiro Watanabe, Charles Makoundi   +6 more
wiley   +1 more source

SHRIMP U-Pb zircon dating of Pedras Grandes Suite, southern Santa Catarina State, Brazil

Anais da Academia Brasileira de Ciências, 2005
Two major magmatic pulses of the granitic Florianópolis Batholith in Santa Catarina State, southern Brazil, occurred between 613±5Ma and 595±5 Ma, during the Neoproterozoic Brasiliano Cycle.
Andréa R. Jelinek, Artur C. Bastos-Neto, Jayme A.D. Leite, Léo A. Hartmann, Neal J. McNaughton   +4 more
doaj   +1 more source

Fluids in the Siilinjärvi carbonatite complex, eastern Finland: Fluid inclusion evidence for the formation conditions of zircon and apatite [PDF]

Bulletin of the Geological Society of Finland, 1995
In the studied zircon and apatite crystals, data recorded two different compositional types of fluid inclusions: Type 1 H2O-CO2 low salinity inclusions (XCO2 = 0.42 to 0.87; XNaCl = 0.001 to 0.005) with bulk densities of 0.73 to 0.87 g/cm3, and Type 2 ...
M. Poutiainen
doaj   +1 more source

Late Pleistocene Volcanic Rocks From Tengchong Volcanic Field at SE Tibetan Plateau: Constraints on Petrogenesis and Mantle and Crustal Processes

Geological Journal, EarlyView.
Early zircon saturation and crystallisation occur in mafic (52–54 wt.% SiO2) lavas at Tengchong volcanic field. These early formed zircons with high δ18O (6.6‰–7.9‰) indicates mantle enrichment by subducted supracrustal materials. ABSTRACT Late Pleistocene (< 0.2 Ma) mafic and evolved volcanic rocks occur in northern Tengchong Volcanic Field, SE ...
Lizhu Wang, Haibo Zou
wiley   +1 more source

A Reassessment of Petrochemistry of ~1.2 Ga Tonalitic Rocks of the Northern Tugela Terrane, Natal Metamorphic Belt, South Africa: Further Constraints on the Evolution of This Belt

Geological Journal, EarlyView.
Our petrochemical studies on ~1.2 Ga granitoids of the Natal Metamorphic Belt, South Africa, do not suggest any property similar to Phanerozoic‐style subduction‐related granitoids. Plot of Kotongweni Tonalite in Y versus Sr diagram (after Moyen 2011), note that most samples have Sr/Y < 50.
Palesa Leuta, Saumitra Misra, Thembiso O. Basupi   +2 more
wiley   +1 more source

Apatite in Carbonatite Preserving Primary Magmatic, Post‐Magmatic Overgrowth, and Post India‐Asia Collision‐Related Hydrothermal Alteration: Evidenced From U–Pb Isotope and Trace Element Geochemistry

Geological Journal, EarlyView.
U–Pb isotope and trace element geochemistry of apatite from carbonatites of Peshawar Plain Alkaline Igneous Province, western Himalaya shows Permo‐Carboniferous magmatism, an additional magmatic pulse during Cretaceous, and post‐magmatic hydrothermal/metasomatism during Oligocene. ABSTRACT U–Pb isotope and trace element geochemistry of apatite combined
Mehboob ur Rashid, Hafiz U. Rehman, Hao‐Yang Lee, Sun‐Lin Chung, Kaushik Das, Kazumasa Aoki, Muhammad Jawad Zeb, Nasir Ahmad, Muhammad Hussain, Hiroshi Yamamoto   +9 more
wiley   +1 more source

Magma Petrogenesis Study Based on Morphology and Texture Of Zircon Minerals: Case Study At The Causative Intrusive In The HLE Porphyry Copper-Gold Prospect, Sumbawa Island, Indonesia

JGEET: Journal of Geoscience, Engineering, Environment and Technology
The zircon mineral is one of the accessory minerals within igneous rocks for its ability to resist hydrothermal and metamorphic processes. By examining their morphology and texture, zircon minerals can provide valuable insights into magma's petrogenesis,
Fadlin, Raden Isnu Hajar Sulistyawan, Arifudin Idrus, Raden Muhammad Asfaro, Hernani Vitorino Nhatinombe, Wildan Nur Hamzah   +5 more
doaj   +1 more source

From Highlands to Henge: Refining the Provenance and Transport Pathways of Stonehenge's Altar Stone

Journal of Quaternary Science, EarlyView.
ABSTRACT The Altar Stone, the 6000 kg central sandstone megalith at Stonehenge in southern England, is suggested to have originated from the Orcadian Basin in northeast Scotland, some 700 km away. However, its source location within this large basin remains unresolved and its mode of transport uncertain.
Anthony J. I. Clarke, Remy L. J. Veness, Christopher L. Kirkland, Chris D. Clark, Niall Gandy, Andy Emery, Sarah L. Bradley, Jeremy C. Ely, Ignéczi Ádám   +8 more
wiley   +1 more source