Geomorphological context of “plinthitic paleosols” in the mediterranean region : examples from the coast of western Liguria (Northern Italy)

The main objectives of this study were to characterize the micromorphological and mineralogical properties of the two plinthitic paleosols and to deduce their formation processes in relation to the geomorphological position. T h e first described paleosol is located on High Plain of Manie and shows morphological characteristics comparable to present- day tropical-area soils, being characterised by the presence of a deep and thick plinthitic horizon overlying a saprolite. Instead the second paleosol is characterised by a thick petroplinthitic horizon and it related to relic terraced landforms of marine origin with very weathered marine and continental deposits on their preserved surfaces. The micromorphological evidence, supported by the mineralogical analyses, suggests a polygenetic origin for this paleosols, in which different geomorphological context played a role both on soil development and profile preservation.