Upper Quaternary coastal palaeoenvironments and palaeosea levels in Las Canteras beach, Gran Canaria (Canary Islands, Spain)

Abstract

Las Canteras beach outcrops are vestiges of palaeoenvironments that represent changes in sea level and/or climate conditions. Using broad sedimentological, mineralogical, geochemical, and dating studies, three different palaeoenvironmental facies were distinguished. (1) The lower facies was defined as beachrock, formed by decametric calcarenite layers, dipping 8–5° seaward and composed mainly of sand grains and two generations of isopachous low magnesium calcite (LMC) cement in a context of lower Holocene interglacial stage (>6600 ± 30 cal. years BP) rising sea level and coastal progradation. (2) During the middle Holocene (about 6600 ± 30 cal. years BP), a coastal progradation phase and/or lower sea level might lead to land emersion and soil development, with an abundance of terrestrial gastropods. (3) The upper Holocene (<6600 ± 30 cal. years BP) aeoleanite facies represents coastal dunes formed by calcarenite levels were identified only in the central arc of the beach, dipping 20° landward and cemented by phreatic LMC and vadose aragonite. This aeolian deposit might represent the highest coast progradation or the end of a low stand in sea level, whereas its cementation likely represents the beginning of the sea level rise towards the present high stand.