This survey is part of a long range project of the Petroleum Division of the Philippine Bureau of Mines to undertake plane table measurements of type sections in sedimentary basins of the Philippines, with the ultimate aim of evaluating the petroleum potential of the country.

In particular this study attempts at a comprehensive review and amplification of the work of Corby, et al (1951) in the Iloilo Basin, through the establishment of type and reference sections, and a definition and classification of sedimentary units in accordance with recent stratigraphic concepts and practices. The field work and preparation of this report were made in accordance with the rules and procedure on nomenclature set by the American Commission on Stratigraphic Nomenclature (1961).