Results 71 to 80 of about 17,505 (279)

A precise late Permian 40Ar/39Ar age for Central Iberian camptonitic lamprohyres

Geologica Acta, 2006
The Avila batholith of central Spain is composed, predominantly, of crustal-melt peraluminous granites cut by small-scale mafic alkaline bodies. Dating of the Gredos sector mafic camptonitic lamprophyre dykes was undertaken to constrain the Late Variscan
J.H. SCARROW, F. BEA, P. GONZÁLEZ MONTERO, J. F. MOLINA PALMA, ALAN VAUGHAN   +4 more
doaj   +1 more source

Paleomagnetism, rock magnetism and geochemical aspects of early Cretaceous basalts of the Paraná Magmatic Province, from Misiones, Argentina [PDF]

, 2006
The basalts of the Posadas Formation were extruded during the huge continental volcanism that affected the Parana Basin in the Lower Cretaceous. We have carried out a paleomagnetic and rock-magnetic study on samples collected along a basalt outcrop ...
Lagorio, Silvia Leonor, Mena, Mabel, Orgeira, Maria Julia   +2 more
core   +1 more source

Intermittent Brittle and Ductile Deformation as Recorded by Dating of Ultramylonites and Pseudotachylytes in Extending Continental Crust (Ivrea‐Verbano Zone, Italy)

Terra Nova, EarlyView.
ABSTRACT Mylonites and pseudotachylytes play a crucial role in defining the rheology of extending continental crust. In this context, determining the age of brittle‐ductile deformation is fundamental to understanding the rifting evolution stages. Here, we investigate the Premosello Shear Zone, an extensional structure of the Ivrea‐Verbano lower crust ...
Stefania Corvò, Chiara Montemagni, Stefano Zanchetta, Antonio Langone   +3 more
wiley   +1 more source

The evolution of Neoproterozoic magmatism in Southernmost Brazil: shoshonitic, high-K tholeiitic and silica-saturated, sodic alkaline volcanism in post-collisional basins

Anais da Academia Brasileira de Ciências, 2006
The Neoproterozoic shoshonitic and mildly alkaline bimodal volcanism of Southernmost Brazil is represented by rock assemblages associated to sedimentary successions, deposited in strike-slip basins formed at the post-collisional stages of the Brasilian ...
Sommer Carlos A., Lima Evandro F., Nardi Lauro V. S., Liz Joaquim D., Waichel Breno L.   +4 more
doaj  

Sea-floor tectonics and submarine hydrothermal systems [PDF]

, 2005
The discovery of metal-depositing hot springs on the sea floor, and especially their link to chemosynthetic life, was among the most compelling and significant scientific advances of the twentieth century. More than 300 sites of hydrothermal activity and
de Ronde, Cornell D. J., Hannington, Mark D., Petersen, Sven   +2 more
core   +1 more source

GEOCHRONOLOGY OF ALKALINE ROCKS FROM THE BURPALA MASSIF (NORTHERN PRIBAIKALYE): NEW U-Pb DATA

Геодинамика и тектонофизика
Geochronological studies have been made on the main types of rocks from the Burpala alkaline massif and two gabbro and gabbro-diorite dikes located nearby.
I. А. Izbrodin, А. G. Doroshkevich, А. V. Malyutina, D. V. Semenova, Т. А. Radomskaya, М. N. Kruk, I. R. Prokopyev, А. Е. Starikova, М. О. Rampilov   +8 more
doaj   +1 more source

First evidence of lamprophyric magmatism within the Subbetic Zone (Southern Spain) [PDF]

, 2010
Two drillings carried out at Cerro Prieto (Province of Málaga), together with additional geophysical data, revealed the existence of an igneous body formed of rock-types previously unknown in the Subbetic zone.
Beccaluva, Luigi, Bianchini, Gianluca, Díaz de Federico, Antonio, Díaz Puga, Miguel Ángel, Galindo Zaldívar, Jesús, Puga, Encarnación, Wijbrans, Jan, Álvarez Valero, Antonio Miguel   +7 more
core   +9 more sources

Magmatismo alcalino potássico saturado em SiO 2 na porção central do Cráton Amazônico, extremo sul do Domínio Uatumã-Anauá, NE do Amazonas, Brasil [PDF]

, 2017
Este trabalho analisa o registro do magmatismo alcalino potássico saturado-SiO 2 do Quartzo-Monzonito Castanhal e do Quartzo-Sienito Ladeira da Vovó. Essas rochas estão localizadas próximas à borda norte da Bacia do Amazonas.
Dantas, Elton Luiz, Macambira, Moacir José Buenano, Souza, Valmir da Silva, Valério, Cristóvão da Silva   +3 more
core   +1 more source

Miocene Alkaline Basaltic Magmatism in Northeastern Tibetan Plateau: Implications for Mantle Evolution and Plateau Outward Growth

Geochemistry, Geophysics, Geosystems
The widespread Cenozoic alkaline magmatism within and around the Tibetan Plateau offers a prime opportunity to probe the nature of the mantle at the depths where basalt magmas originate.
Yue Che, Dong Liu, Zhidan Zhao, Yaoling Niu, Fang‐Zhen Teng, Donald J. DePaolo, Xuehui Yu, Di‐Cheng Zhu, Ningyuan Qi, Xuanxue Mo   +9 more
doaj   +1 more source

AGE OF THE AMNUNAKTA MONZOGABBRO-MONZODIORITE MASSIF IN THE SOUTHERN FRAMING OF THE SIBERIAN CRATON

Геодинамика и тектонофизика, 2020
The first geochronological data have been obtained for Amnunakta massif composed of monzogabbro-monzodiorite and located in the southeastern part of the Selenga-Stanovoy superterrane.
I. V. Buchko, A. A. Rodionov, E. B. Salnikova   +2 more
doaj   +1 more source