BIBLIOS

Tipo
Capítulo em Livro


Título
Silica gel microtextures in siliceous exhalites at the Soloviejo manganese deposit, Spain

Participantes na publicação
R. C. G. S. Jorge (Author)
Dep. Geologia
CREMINER
IDL
J. M. R. S. Relvas (Author)
Dep. Geologia
IDL
F. J. A. S. Barriga (Author)
Dep. Geologia
CREMINER
IDL

Resumo
Well-preserved primary textural features were recognized in cherts and jaspers that form one of the manganese ore-hosting units of the Soloviejo Mn deposit, in the Iberian Pyrite Belt. These include (i) spherulitic, (ii) banded and (iii) brecciated. The spherulites (0.04-0.3 mm) consist of a central core of minute grains of hematite or quartz, rimmed by chalcedony or microcrystalline quartz. Banded jaspers show no spherulitic textures. Banded textures are made up by alternations of micro- to meso-bands of silica and hematite. They often show soft-sediment deformation features, such as microslumps, pinch-and-swell, and load cast. Diagenetic brecciation overprints these pristine textures. Breccias consist of jasper fragments (mm to cm), affected by total or partial recrystalization, cemented by different proportions of microcrystalline quartz. Primary textures in siliceous hydrothermal precipitates reflect different stages of formation and diagenetic maturation of its silica gel precursor. Their interpretation helps in constraining the initial conditions assisting the hydrothermal activity at the Soloviejo deposit, and its early evolving stages.

Editor
Mao, J; Bierlein, FP


Instituição
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA

Suporte
Mineral Deposit Research: Meeting the Global Challenge

Identificadores da Publicação

Editora
Springer Berlin Heidelberg



Identificadores do Documento
DOI - https://doi.org/10.1007/3-540-27946-6_161
URL - http://dx.doi.org/10.1007/3-540-27946-6_161