Mineralogía y génesis de las arcillas del Campo de Gibraltar. III. Unidad de Algeciras

Abstract

The study of Algelciras unit, iniciated with the seríes of Rinconcillo (Ruiz Cruz et al., 1987), is now completed. The mineralogical results of the Punta Tarifa series are analyzed, and are compared with the former studies, and, also conclusions relative to the Algeciras unit are exposed. The Punta Tarifa series is characterized by the high content of illite-rich interestratified clay minerals (illite-vermiculite; illite-smectite, illite -vermiculite-smectite, illite-chlorite) and the constant presence of chlorites of variable genesis. The differences between these series come from the different content in clay minerals, specially, smectite, palygorskite, kaolinite and chlorite. Differences are related with chemical characteristics of depositional and/or diagenetic environment and, also, with different alteration degree of detrític minerals.