Tracing provenances of Quaternary dust deposits in dammed valleys (vegas) on Lanzarote

On Lanzarote (eastern Canary Islands), several valleys were dammed by volcanic activity during the Quaternary, creating closed sedimentary basins locally known as “vegas”. Since their formation, these basins have acted as natural sediment traps, preserving layered sequences of aeolian dust, volcanic material, and colluvial slope deposits. The sediments are characterized by an alternation of pale carbonate-enriched layers (PCLs) and reddish clay-enriched layers (RCLs), reflecting cyclic sedimentation patterns.

In this study, we apply principal component analysis (PCA) to geochemical (XRF) and mineralogical (XRD) data to differentiate sediment sources and assess the provenances of dust inputs. The PCA results show a clear geochemical and mineralogical pattern within the profiles, enabling interpretations of sediment origins and depositional dynamics. PC1 separates silty, quartz- and Zr-dominated dust from clay-rich inputs, linked to kaolinite, and basalt-derived material enriched in Fe, Ni, and Zn. These local materials are also separated from V and Rb by PC2. The distinct clustering of quartz, kaolinite, and K-feldspar points to contributions from multiple North African dust source areas. This geostatistical approach provide the basis for further investigating dust source areas and linking the findings to regional palaeoclimatic developments across the Canary–North Africa domain.