Origen de las aguas subterráneas hipersalinas asociadas al complejo olistostrómico del Guadalquivir (Andalucía)

  1. F. Moral Martos 1
  1. 1 Universidad Pablo de Olavide
    info

    Universidad Pablo de Olavide

    Sevilla, España

    ROR https://ror.org/02z749649

Revista:
Geotemas (Madrid)

ISSN: 1576-5172

Ano de publicación: 2021

Título do exemplar: X Congreso Geológico de España

Número: 18

Páxinas: 312-315

Tipo: Artigo

Outras publicacións en: Geotemas (Madrid)

Resumo

The hydrology of the Andalusian Campiña (southern strip of the Guadalquivir Depression) is characterized by the existence of hypersaline groundwater, responsible for the large number of salty streams in the region. The brine arises in small springs that have traditionally been used for salt production. The waters have a weak hydrothermal character, with temperatures that usually exceed between 4 and 6 ºC to the environmental average temperature. In general, waters have saline contents between 150 and 300 mg/L and a markedly sodium chloride hydrochemical facies. The high concentrations in Cl-, Na+, SO 42- and Ca2+ imply the dissolution of halite and gypsum from the Triassic lutites and evaporites (Keuper facies) of the Guadalquivir olistostromic complex. The absence of halite at the most superficial levels, the low permeability of the lutites and the hydrothermalism imply a deep origin of the waters that can hardly be related to the current recharge of meteo- ric waters. Therefore, a fossil origin of the brine is proposed, which would be expelled as erosive dismantling of the Triassic materials occurs.