Rocky cliff evolution in the Cantabrian coast (N Spain)

The pace of erosion processes leading to the landward retreat of rocky cliffs could possibly be enhanced by climate change and rising sea level conditions. Satellite and aerial imagery provide a means for quantifying rocky cliff retreat at decadal scale, while retreat rates over several millennia can be estimated by measuring the concentration of cosmogenic nuclides of samples taken from abrasion platforms. In this contribution we analyze the evolution of rocky cliffs at two locations of the Cantabrian coast in northern Spain, both located in the Asturias region, by combining these techniques. The analysis of aerial images shows that one of the sites has remained quite stable over the last decades, while the other stands evidence of active slope instabilities over, at least, the last two decades. The cliff retreat rates estimated based on ¹⁰Be concentration measurements from abrasion platforms preserved at the cliff base at both study sites are compatible with slow rates of retreat, of the order of a few centimeters per year. 

Research funding: RETROCLIFF (PID2021-122472NB-100, MCIN/AEI/FEDER, UE) and GEOCANTABRICA (IDE/2024/000753, SEK-25-GRU-GIC-24-072, SEKUENS, Principado de Asturias).