Mineralogical, petrographical and geochemical study of the post-magmatic process from the Freixiosa-Mesquitela Granite, Mangualde, Portugal: Preliminary data [Estudo mineralógico, petrográfico e geoquímico do processo pós-magmático do granito de Freixiosa-Mesquitela, Mangualde, Portugal: Dados preliminares]

• Type: Article in International Scientific Journal
• Date: 2014

Authors

Maia, M (Author) Other; Jaques, L (Author) Other; Bobos, I (Author) FCUP; Bobos, I (Author) Other; Noronha, F (Author) FCUP; Noronha, F (Author) Other

Journal

Title: Comunicações Geológicas

Vol. 101

Pages: 137-142

ISSN: 0873-948X

Publisher: LNEG - Laboratório Nacional de Energia e Geologia

Indexing

ISI Web of Knowledge

Scopus - 1 Citation

Other information

Authenticus ID: P-00G-4YR

Abstract (EN): This work aims the study of the evolution of hydrothermal processes observed in the Freixiosa-Mesquitela granite. Three distinct paragenetic sequences associated with the K+/Na+ alteration (microcline, albite, muscovite and secondary biotite), phylic alteration (sericite, chlorite), and propylitic alteration (epidote, chlorite, hematite). The textural and mineralogical changes observed reflect the chemical changes recorded by the altered rocks studied. Mass balance calculations confirm that the altered rocks display losses of SiO<inf>2</inf>, CaO, Na<inf>2</inf>O and gains on Al<inf>2</inf>O<inf>3</inf>, FeO and K<inf>2</inf>O. One sample (M2) shows also Na<inf>2</inf>O gains, related with albitization processes. © 2014 LNEG ¿ Laboratório Nacional de Geologia e Energia IP

Language: Portuguese

Type (Professor's evaluation): Scientific