Results 41 to 50 of about 1,291 (133)

Petrogenesis and tectonic implications of the late Paleoproterozoic (ca. 1.7 Ga) post-collisional magmatism in the southwestern Gyeonggi Massif at Garorim Bay, South Korea

Journal of Asian Earth Sciences: X, 2021
The Precambrian basement of the Gyeonggi Massif in the central Korean Peninsula consists mainly of Paleoproterozoic (2.0–1.8 Ga) gneisses. In this study, we present petrological, zircon U–Pb age and Hf isotope, and whole-rock geochemical and Sr–Nd–Pb ...
Ji-In Kim, Sung Hi Choi
doaj   +1 more source

Salt Range Formation of Pakistan Preserves Unique Record of Volcanic Fertilization During the Ediacaran Shuram Excursion

Terra Nova, EarlyView.
ABSTRACT Thin, discontinuous, organic‐rich oil shale beds in the siliciclastic‐evaporitic Salt Range Formation (SRF) of Pakistan are of approximate Neoproterozoic to Cambrian age based on stratigraphic constraints. The beds are enriched (26–43 wt.% total organic carbon, TOC) in aliphatic organic matter (OM) of low thermal maturity despite their ...
Paul C. Hackley, Ryan J. McAleer, Jay M. Thompson, Brett J. Valentine, Imran Khan   +4 more
wiley   +1 more source

Enlargement of the area of the Timpton Large Igneous Province (ca. 1.75 ga) of the Siberian craton

Геодинамика и тектонофизика, 2019
We present new geochronological data on dolerites from the Chaya dyke swarm of the Baikal inlier of the Siberian craton. The U‐Pb dating of baddeleyite from one dyke located at the SW end of the Chaya dyke swarm yielded an age of 1752±6 Ma, similar to ...
D. P. Gladkochub, T. V. Donskaya, R. E. Ernst, U. Söderlund, A. M. Mazukabzov, M. N. Shokhonova   +5 more
doaj   +1 more source

Rare Earth Element Potential in the Araí Rift Metavolcanic, Central Brazil: Gamma‐Ray Signatures, Mineralogy and Exploration Implications

Terra Nova, EarlyView.
ABSTRACT Although central Brazil hosts significant ion‐adsorption rare earth element (REE) deposits associated with A‐type granites, their coeval volcanic counterparts have been largely overlooked as exploration targets. This study demonstrates that acidic metavolcanic rocks of the Araí Group share strong radiometric, geochemical and mineralogical ...
Yuri Ribeiro, Nilson Francisquini Botelho, Valmir da Silva Souza, Diego Guilherme da Costa Gomes   +3 more
wiley   +1 more source

Multi‐Mineral Geochronology Across the Neoproterozoic Brasília Nappe Stack: Constraints on Thermal Resetting and Metamorphic Architecture

Terra Nova, EarlyView.
ABSTRACT The Southern Brasília Orogen formed during Western Gondwana's final assembly and comprises nappe systems piled against the São Francisco Craton. We present new rutile U–Pb ages from the lowermost Canastra Group (> 2.2 Ga) and the uppermost Carrancas Group (~560 Ma), integrated with published zircon, monazite, garnet, and mica ages from the ...
Rodrigo Irineu Cerri, Alex J. Choupina A. Silva, Tamiris Pagotti Gonçalves Pinto, Rodrigo Prudente de Melo, George Luiz Luvizotto, Regiane Andrade Fumes, Fabrício de Andrade Caxito, Renato Moraes   +7 more
wiley   +1 more source

Temporal and Hf isotope geochemical evolution of southern Finnish Lapland from 2.77 Ga to 1.76 Ga [PDF]

Bulletin of the Geological Society of Finland, 2012
The southern Finnish Lapland area in the central part of the Fennoscandian shield is a geologically complex zone comprising several Archean blocks and Paleoproterozoic supracrustal belts all of which are intruded by voluminous Paleoproterozoic granites ...
L.S. Lauri, T. Andersen, J. Räsänen, H. Juopperi   +3 more
doaj   +1 more source

Vetreny belt as a geological heritage of unique paleoproterozoic tectonomagmatic processes in the Fennoscandin shield

Известия высших учебных заведений: Геология и разведка
We presented the history of discovery and development of geological hypotheses about the conditions of formation of one of the largest Paloproterozoic structures of the Baltic Shield  — the Vetreny Belt.
S. V. Mezhelovskaya, К. I. Yushin, А. D. Mezhelovsky   +2 more
doaj   +1 more source

Mafic-ultramafic intrusions of Matokulma, Palojärvi, and Hongonniittu within the Central Finland Granitoid Complex with special reference to their petrogenesis and ore potential [PDF]

Bulletin of the Geological Society of Finland
We describe three previously unknown or poorly studied mafic-ultramafic intrusions (Matokulma, Palojärvi, Hongonniittu) from the south-central part of the Paleoproterozoic Central Finland Granitoid Complex (CFGC).
Seppo Karvinen, Hannu V. Makkonen, Perttu Mikkola, O. Tapani Rämö, Hannu Huhma, Matti Niskanen   +5 more
doaj   +1 more source

Geological and isotopic characteristics of granites from the Western Pernambuco-Alagoas Domain: implications for the crustal evolution of the Neoproterozoic Borborema Province

Brazilian Journal of Geology
The Western Pernambuco-Alagoas Domain is a complex tectonic domain of the Southern part of the Neoproterozoic Borborema Province. It borders the Northern margin of São Francisco Craton. U-Pb and Sm-Nd data discussed in this work show that, in the Western
Rodrigo Fabiano da Cruz, Márcio Martins Pimentel, Ana Cláudia de Aguiar Accioly, Joseneusa Brilhante Rodrigues   +3 more
doaj   +1 more source

Paleoproterozoic post-orogenic magmatism in southern Finland; geochemical, geochronological and Sr-Nd isotopic constraints on origin and magmatic evolution [PDF]

Bulletin of the Geological Society of Finland
Fifteen post-orogenic, basic to acidic High-Barium-Strontium (HiBaSr) intrusions of shoshonitic affinity have been recognized in central and southern Finland.
Oliver Teräs, Kaisa Nikkilä, Perttu Mikkola, Anna Kotilainen, Olav Eklund, O. Tapani Rämö   +5 more
doaj   +1 more source