REE and other trace and major elements in the topsoil layer of Santiago island, Cape Verde

► First total chemical contents in Santiago soils for a low density geochemical atlas. ► REE differentiate soils with contrasting parent materials, particularly carbonatites. ► Total contents of Cs, As and Ga are associated with the finer soils. ► Arsenic contents increase and availability decreases, with decreasing particle size. ► Low Cr extraction (∼30%) by aqua regia, despite the high contents in soils.