RT info:eu-repo/semantics/article
T1 Caracterización de pizarras comerciales del NO de España a partir de DRX, microscopía electrónica (EMPA , SEM, TEM) y FRX
T2 XRD, electron microscopy (EMPA, SEM, TEM) and XRF characterization of roofing slates from NW Spain
A1 Gómez Fernández, Fernando
A1 Ward, C.R.
A1 Bauluz Lázaro, Blanca
A2 Prospeccion e Investigacion Minera
K1 Ingeniería de minas
K1 Rietveld Method
K1 Truchas Syncline
K1 Electron Microscopy
K1 Electron Microprobe
K1 3318 Tecnología Minera
AB [EN] The aim of this paper is to characterize thoroughly the mineralogy and petrography of a set often different types of commercial roofing slates from the NW of Spain. Representative samples ofeach type have been studied by transmitted and reflected-light optical microscopy, scanning andtransmission electron microscopy, electron microprobe, X-ray fluorescence and X-ray diffractiontechniques. Quantitative analyses of the main mineral percentages in each slate sample weremade from XRD data using the Siroquant™ interpretation software system, based on Rietveldprinciples. The microscopic textures of the slates vary depending on the samples, and lepidoblasticto porphyroblastic textures have been described. Some slates with bands of sand layers displaygrano-lepidoblastic textures. White mica, quartz, chlorite and feldspar (albite) are the main minerals.The white micas and the chlorites have similar compositions in all the analyzed samples. Electronmicroprobe analyses indicate that the micas are K-rich dioctahedral varieties, having a composition close to muscovite with a phengitic component. They show the following average formula: (Na0.16K1.39 Ca0.01) (Al3.83 Ti0.03 Fe0.15 Mg0.14) (Si6.22 Al1.78) O20 (OH)4. The chlorites are magnesian chamositeswith an average formula of (Na0.02 K0.04 Ca0.01Al3.24 Ti0.01 Fe5.13 Mn0.03 Mg3.28) (Si5.23 Al2.77) O20 (OH)16.Accessory minerals are ilmenite, rutile, sulphides, carbonates, graphite, monazite, apatite, zirconand tourmaline. Two different associations of sulphide minerals are distinguished: 1) Type I withpyrite, pyrrhotite, pentlandite, cobaltite, chalcopyrite, sphalerite, galena, ullmannite and gersdorffiteoccurring as pre-kinematic porphydic aggregates; b) Type II mainly with post-kinematic pyrite andsporadic chalcopyrite and galena. The main carbonate mineral is ankerite ((Mg0.26, Ca0.49, Mn0.05,Fe0.19) CO3) with minor calcite and siderite also present.
PB Instituto Universitario de Geología Isidro Parga Pondal
SN 0213-4497
LK https://hdl.handle.net/10612/20619
UL https://hdl.handle.net/10612/20619
NO Gómez Fernández, F., Ward, C. R., & Bauluz Lázaro, B. (2009). Caracterización de pizarras comerciales del NO de España a partir de DRX, microscopía electrónica (EMPA, SEM, TEM) y FRX. Cadernos do Laboratorio Xeolóxico de Laxe: Revista de xeoloxía galega e do hercínico peninsular, 34, 127-142.
DS BULERIA. Repositorio Institucional de la Universidad de León
RD Jul 11, 2024