Albitization evidences of Mesozoic carbonatespetrological study of authigenic albites in the northwest of the BortziriakCinco Villas Massif, eastern Basque-Cantabrian Basin

  1. Martin Ladron de Guevara 1
  2. Arantxa Bodego 1
  3. Eneko Iriarte 2
  1. 1 Geologia Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea. Leioa
  2. 2 Laboratorio de Evolución Humana, Departamento de Historia, Geografía y Comunicación – Laboratorio de Isótopos Estables IsoTOPIK, Edificio de I+D+i, Universidad de Burgos, Burgos
Revista:
Geogaceta

ISSN: 0213-683X

Ano de publicación: 2023

Número: 74

Páxinas: 31-34

Tipo: Artigo

Outras publicacións en: Geogaceta

Resumo

The presence of authigenic Na-feldspars in sedimentary carbonate rocks is unusual and its origin is controversial in terms of genesis and timing. The use of optical microscopy, cathodoluminescence and in situ semi-quantitative EDX analysis techniques, has allowed the identification and characterization of authigenic albite crystals in the Mesozoic pre- and syn-rift carbonates of the northwestern margin of the Bortziriak-Cinco Villas Massif, in the northeastern Basque-Cantabrian Basin (western Pyrenees). The euhedral habit, crystal size, spatial distribution and crosscutting relationships, together with the pure albitic composition, suggest a relatively early replacement origin. Compaction of sediments during burial, besides possible fluid migration linked to the intense syn-rift halokinetic activity, may have been decisive for the mobilisation of cations, and hence, for the albitization of the carbonate rocks.