Litoestratigrafía y mineralogía del yacimiento paleontológico de Makro-Las Rejas (Mioceno, Cuenca de Madrid)

  1. Omid Fesharaki 1
  2. Juan Antonio Cárdaba 2
  3. María Presumido 2
  4. Javier Salas-Herrera 1
  1. 1 Área de Paleontología, Departamento de Geodinámica, Estratigrafía y Paleontología. Facultad de Ciencias Geológicas. Universidad Complutense de Madrid
  2. 2 Geosfera C.B. Departamento de Innovación y Desarrollo. Madrid
Journal:
Geogaceta

ISSN: 0213-683X

Year of publication: 2020

Issue: 68

Pages: 15-18

Type: Article

More publications in: Geogaceta

Abstract

The lithostratigraphic characteristics of a new Miocene vertebra-te fossil site in the Madrid Basin are described. The stratigraphic succession is mainly formed of silty-clayey and marly lithologies, depo-sited in palustrine-lacustrine environments. A preliminary analysis of the mineralogy indicates predominance of phyllosilicates, followed by feldspars, quartz, carbonates (calcite and dolomite in very varia-ble quantities) and local evidence of gypsum. Smectites predominate in the clay fraction (always more than 70%) followed by micas and varying amounts of sepiolite and chlorite and/or kaolinite. Microtextures show different types of smectite particle associations generally forming honeycomb textures. Local modification of the microtexture due to bioturbation is observed, as well as evidence of microbial action.