Foraminiferal correlation of Tertiary mollusc horizons of the soutern Caribbean area

Abstract

Correlations of conspicuous Tertiary mollusc horizons described from the southern Caribbean area are attempted on associated micropalaeontological evidence. By this method the rich mollusk horizons characteristic of the Springvale Formation of Trinidad, the Punta Gavilán Formation of Venezuela, and the Tubará Formation of Colombia are considered time-correlatable at the Early Pliocene level. The Cantaure mollusc horizon of the Paraguaná Peninsula of northern Venezuela contains an Early Miocene (Burdigalian) microfauna and is correlatable with that of the basal part of the Castilletes Formation of the Guajira Peninsula of northern Colombia and the Quiroz horizon of the La Rosa Formation of the Maracaibo Basin. The 'Raetomya Shales' of the Jarillal Formation of western Venezuela correlate with similar macrofaunas found in the Caus Formation and other transitional facies units associated with the contact of the Middle Eocene Misoa and Pauji Formations of the Maracaibo Basin, and those of the Ceru Mainsji Formation of the island of Curaçao. These horizons can be clearly calibrated with the Truncorotaloides rohri and Orbulinoides beckmanni zones of Bolli's (1966) planktonic foraminiferal zonation. There is also micropalaeontological evidence to suggest that the Hannatoma horizon of western Venezuela can be associated with the final regressive depositional phase of the Middle Eocene throughout northwestern South America.