The Open Geography Journal

2014, 6 : 9-17
Published online 2014 June 13. DOI: 10.2174/1874923201406010009
Publisher ID: TOGEOGJ-6-9

Tributary Alluvial Fan-Responses to Base-Level Fall by Axial Fluvial Incision: A Case in the Guadalquivir Valley (C rdoba, Spain)

M.A. Núñez Granados and J.M. Recio Espejo
Ecology Department (Physical environment and Geomorphology), Rabanales Campus, University of Cordoba, 14071 Cordoba, Spain.

ABSTRACT

The geomorphological, sedimentological and pedological analysis of a group of 11 alluvial fans located in the northern flank of the Guadalquivir Valley has shown that their genesis and evolution were controlled by base-level fall caused by axial fluvial incision of the Guadalquivir River during the Quaternary.

The morphometric and morphological features of the study fans (i.e.: elongated plan-view, straight and concave longitudinal profiles, shallow incised channels in proximal sectors and shallow deposits) suggest that fan accommodation was predominantly progradational and the fluvial incision of the Guadalquivir River was therefore, insufficient to trigger distal erosion of the fans.

The absence of mature red soils provides evidence of fan activity during the Pleistocene, while young soils on the fan surfaces suggest that the fan dynamics became non-functional during the Early Holocene. The absence of Neolithic/Chalcolitic artefacts in the fan sediments supports this idea.

Keywords:

Alluvial fan, base-level, Mediterranean.