Search results for "rock"

"Jerusalemin urheilutalossa oli sellaiset rutiinibileet" : raamatulliset alluusiot Juice Leskisen rocklyriikassa

1997

Age, Nd–Hf isotopes, and geochemistry of the Vijayan Complex of eastern and southern Sri Lanka: A Grenville-age magmatic arc of unknown derivation

2013

Abstract The ca. 1.0–1.1 Ga Vijayan Complex (VC) of eastern and southeastern Sri Lanka is one of three high-grade metamorphic terranes making up the basement of the island and is in tectonic contact with the adjacent, older Highland Complex. It consists predominantly of granitoid gneisses ranging in composition from diorite to leucogranite, with a distinct calc-alkaline geochemical signature, and is interpreted as a magmatic arc. Strong ductile deformation has obliterated almost all original intrusive relationships. High-grade metamorphism during the Pan-African event at ca. 610–520 Ma has produced widespread granulite-facies assemblages that are now largely retrogressed and were affected b…

Melt production, redistribution and accumulation in mid-crustal source rocks, with implications for crustal-scale melt transfer

2014

Abstract Ascent of granitic melt initiates under suprasolidus conditions in the mid- to lower crust before continuing through subsolidus rocks to higher crustal levels. Whereas migration of melt in suprasolidus rocks can occur in pervasive net-like structures and involve relatively small melt volumes, ascent through the subsolidus crust requires more focused, dyke-like structures and larger volumes to prevent freezing. Migmatites in the Aus granulite terrain, southern Namibia, preserve evidence that large-scale melt redistribution and accumulation occurred in the near-source region under suprasolidus conditions. Melt that was mainly produced in metapelitic rocks utilised pervasive small-sca…

El Cinto de las letras (Dos Aguas), revisió del panell 55 anys després de la seua publicació

2006

En aquest paper revisem el panell llevantí del Cinto de las Letras, Dos Aguas (Valencia). Presentem els nous calcs realitzats, l´estudi de la composició i de l´estil basat en la figura humana i la seqüència d´execució i addició que desprén de l´analisis de les figures.

Proterozoic dykes of Salvador and Ilhéus-Olivença areas: a geological geoghemical comparison

1991

Geochemical characteristics of Cretaceous carbonatites from Angola

1999

Abstract The Early Cretaceous (138–130 Ma) carbonatites and associated alkaline rocks of Angola belong to the Parana-Angola-Etendeka Province and occur as ring complexes and other central-type intrusions along northeast trending tectonic lineaments, parallel to the trend of coeval Namibian alkaline complexes. Most of the Angolan carbonatite-alkaline bodies are located along the apical part of the Mocamedes Arch, a structure representing the African counterpart of the Ponta Grossa Arch in southern Brazil, where several alkaline-carbonatite complexes were also emplaced in the Early Cretaceous. Geochemical and isotopic (C, 0, Sr and Nd) characteristics determined for five carbonatitic occurren…

Controls on lineation development in low to medium grade shear zones: a study from the Cap de Creus peninsula, NE Spain

2002

Lineations composed of similarly oriented elongate mineral aggregates or grains are a common feature in deformed rocks, but it is unclear which factors control the development of such lineations. Field observations and microstructural analysis of samples, which were taken from discrete greenschist to lower amphibolite facies shear zones of the easternmost Variscan Pyrenees, show that strain is only one of several factors that control the strength and type of a lineation. Dynamic recrystallization, metamorphic reactions and rigid body rotation are also important controlling factors for the development of lineations. The most important of these is dynamic recrystallization. The way in which d…

Boudinage classification: end-member boudin types and modified boudin structures

2004

In monoclinic shear zones, there are only three ways a layer can be boudinaged, leading to three kinematic classes of boudinage. These are (1) symmetrically without slip on the inter-boudin surface (no-slip boudinage), and two classes with asymmetrical slip on the inter-boudin surface: slip being either (2) synthetic (S-slip boudinage) or (3) antithetic (A-slip boudinage) with respect to bulk shear sense. In S-slip boudinage, the boudins rotate antithetically, and in antithetic slip boudinage they rotate synthetically with respect to shear sense. We have investigated the geometry of 2100 natural boudins from a wide variety of geological contexts worldwide. Five end-member boudin block geome…

Documentação digital da arte rupestre: apresentação e avaliação do método em dois sítios de Monte Alegre, Amazônia, Brasil

2013

Um dos aspectos mais importantes no estudo da arte rupestre é a documentação. No Brasil, são raros os trabalhos que apresentam os métodos e as técnicas empregados na documentação deste tipo de vestígio arqueológico. Grande parte dos estudos publicados no país está voltada para a classificação, a terminologia, as definições crono-estilísticas, interpretações e comparações entre conjuntos gráficos. Atualmente, a fotografia digital e os programas de manipulação de imagem constituem ferramentas de grande utilidade e precisão para a documentação da arte rupestre. Este artigo apresenta os resultados da aplicação do método do decalque digital na Amazônia, desenvolvido pelo Departamento de Arqueolo…

Basking in Reflected Glory and Blasting

2007

This study examines, in soccer fanzines, two identity-management strategies—basking in reflected glory (BIRGing) and blasting—of two groups of highly identified soccer fans with allegiance to the same team. Results show strong support for the BIRG phenomenon among both ultra fan groups but little evidence of the blasting phenomenon among either group. The implications of these findings are discussed in regard to social identity management among sports fans.