RT Journal Article
T1 Sequence stratigraphy of Holocene incised-valley fills and coastalevolution in the Gulf of Cádiz (southern Spain)
A1 Dabrio, Cristino J.
A1 Zazo Cardeña, Caridad
A1 Lario Gómez, Javier
A1 Goy Goy, José Luis
A1 Sierro, Francisco Javier
A1 Borja, Francisco
A1 González Delgado, José Ángel
A1 Flores Villarejo, José Abel
AB This first sedimentary interpretation of two incised-valley fills in the Gulf of Cádiz (southern Spain), whichaccumulated during the last fourth-order eustatic cycle in response to fluvial incision, changes of sea level, andcorrelative deposition, relates the filling of the estuarine basins and their barriers with four regional progradationphases, H1 to H4. The cases studied are the wave-dominated Guadalete, and the mixed, tide and wave-dominatedOdiel-Tinto estuaries. The sequence boundary is a type-1 surface produced during the lowstand of the Last Glacialperiod ca. 18 000 14C yr BP. No fluvial lowstand deposits were found in the area. Due to rapid transgression thevalley fills consist of transgressive and highstand sediments. The maximum landward advance of the estuarinebarriers occurred ca. 6500–6000 14C yr BP during the maximum of the Flandrian transgression, but there is noevidence of sea level rising appreciably above the present. A large part of the estuaries was filled during H1 (ca.6500–4400 14C yr BP) but ravinement by shifting tidal inlets destroyed most of the coeval barriers. During theH2 phase (ca. 4200–2550 14C yr BP) sedimentation was favoured by arid conditions and concentrated in the axialestuarine zones and the barriers. Between H2 and H3 prevailing winds changed from W to WSW, increasing spitgrowth to the east and south-east. Progradation of bay-head deltas and flood-plains during H3 (ca. 2300–800 14C yrBP) and H4 (500 yr ago to the present) further reduced the accommodation space in the largely-filled valleys, andsediment by-passed the estuaries and accumulated in the estuarine barriers as fast-growing spits. Arid conditionsand increasing human activity have caused rapid coastal modifications.
PB Royal Geological and Mining Society of the Netherland
SN 0016-7746
YR 1999
FD 1999
LK https://hdl.handle.net/20.500.14352/57475
UL https://hdl.handle.net/20.500.14352/57475
LA eng
DS Docta Complutense
RD 1 may 2024