Peloides de glauconita y apatito en sedimentos carbonatados mesozoicos del sector oriental de la Zona Subbética (provincia de Alicante).

  1. L.M. Nieto 1
  2. J. Jimenez Millán 1
  3. J.M. Molina 1
  4. F. Nieto 2
  1. 1 Departamento de Geología. Universidad de Jaén.
  2. 2 Departamento de Mineralogía y Petrología. Universidad de Granada.
Journal:
Geogaceta

ISSN: 0213-683X

Year of publication: 1996

Issue: 20

Pages: 1496-1498

Type: Article

More publications in: Geogaceta

Abstract

Glauconite and apatite peloids occur in jurassic and cretaceous bioclast-bearing carbonate rocks from the Algayat-Crevillente Unit (Subbetic Zone). The size and the morphology of peloids are controlled by the bioclasts. Internal texture commonly evidence that the glauconite form nuclei surrounded by apatite. K content is elevated in both stratigraphic positions but higher in the cretaceous glauconites than the jurassic glauconites. Textural and chemical evidence indicate a model of glauconitization with two steps: an early dissolution-crystallization process and a further process of K-enrichment. Low K-content in jurassic glauconites can be explained by the calcitic early diagenetic cementation which stops the second step of glauconitization, while the low Fe content of this glauconites could be a later effect due to a deeper burial diagenesis.