Micromorphological and chemical complexities of a lateritic profile from basalt (Jos Plateau, Central Nigeria)

A ferricrete-capped lateritic profile developed on basaltic saprolite is de scribed. Within both ferricrete and the immediately underlying soft laterit e, two types of sesquioxidic cement are distinguished: the isopachous goeth itic intergranular cement which is predominant and is interpreted as an ind ication of past phreatic conditions; and the Fe-stained meniscus cement whi ch is interpreted as a sign of vadose conditions. The observed features are suggested to reflect changing drainage conditions related to morphological rejuvenation of the profile, in full accordance w ith previous hypotheses developed on the basis of geomorphological consider ation. (C) 2000 Elsevier Science B.V. All rights reserved.