Hipótesis sobre el origen de la laguna de Medina (Jerez de la Frontera, Cádiz)

  1. M. Rodríguez-Rodríguez 1
  2. M. Díaz-Azpiroz 1
  3. F. Pérez-Valera 2
  4. F. Moral 1
  1. 1 Universidad Pablo de Olavide
    info

    Universidad Pablo de Olavide

    Sevilla, España

    ROR https://ror.org/02z749649

  2. 2 Universidad de Jaén
    info

    Universidad de Jaén

    Jaén, España

    ROR https://ror.org/0122p5f64

Revue:
Geotemas (Madrid)

ISSN: 1576-5172

Année de publication: 2012

Titre de la publication: VIII Congreso Geológico de España, Oviedo, 17-19 de julio, 2012.

Número: 13

Pages: 1563-1566

Type: Article

D'autres publications dans: Geotemas (Madrid)

Résumé

In this paper we propose a hypothesis for the formation of the closed basin hosting Medina playa-lake, one of the main shallow lakes of Andalusia. The lake is located S of the flood plain of the Guadalete river. It is separated from the alluvial sediments of the river by two narrow ridges, aligned in an E-W direction. Multi-coloured marly rocks, dolomites and gypsum with a Triassic origin make up these hills. At the top of such hills, rounded-pebbles conglomerates with a subbetic origin appear. The conglomerates are interpreted as alluvial deposits (terraces) associated with older stages of deposition of the Guadalete river. These sediments are located more than 40 m above the current level of the river and exhibit fold deformation, oriented roughly WNW-ESE. With the information obtained, it is presumed that the main structure that has generated these hills would be an antiform with a core of Triassic and Miocene sediments. This structure aids the formation of a barrier to the natural runoff flow to the north, remaining the leading cause for the genesis of the endorheic basin that leads to the establishment of the playa-lake.