The Pleistocene double tombolo of Calpe and the submerged fault scarps between Moraria Point and Ifach Rock (southeast Iberian Peninsula)

Double and triple tombolos are rare on Holocene coasts. It has been proposed that the double tombolo of Calpe has existed since the Upper Pleistocene. The aim of this work is to demonstrate, map and deduce the implications of the existence of this double tombolo in the Upper Pleistocene. The analysis of high-resolution bathymetry and seabed classes mapping, complemented with field work, has allowed mapping the presence of a submerged bar of a calcarenite with abundant ooid forms 2-km long and with a crest depth between 3 and 4 m, separated from the present shore by a depression with a maximum of 6 m. The bimodal wave regime facilitated the formation first of this northern tombolo and later or synchronously formed the western tombolo, leaving the lagoon in its interior. The analysis of this and other double tombolos leads to define them as a new model of convergent paired spits, different from the genesis of the simple tombolos. In the submerged zone, previously unmapped faults have also been identified.