LA PAZ, Shales

CRETACEOUS (upper Campanian-Maestrichtian)

State of Zulia, Venezuela

Author of name: Staff of Caribbean Petroleum Co., 1948.

Original reference: Staff of Caribbean Petroleum Co.,1948, p. 599.

Original description: ibid.

According to the Staff of Caribbean Petroleum Co., the La Paz shales, named after the La Paz oilfield Maracaibo district, State of Zulia, reach a maximum thickness of 2000 feet, which is generally somewhat reduced in La Paz, probably due to faulting. The La Paz shales consist of dark gray shales, in which a thin sand zone (the P-62 sand) is intercaled in some places about 350 feet above the base of the shales. The lower third of the formation contains a rich marine foraminiferal fauna which allows close correlation with the Colón formation. The upper two-thirds are faunally much poorer and correspond with allorpart of the Mito Juan formation. The La Paz shales rest on the Socuy limestone member of the Colón formation and are overlain by the Guasare formation.

The top of the La Paz shales is taken at the base of the lowest limestone of the Guasare formation, or, in areas where this limestone is not developed, at an arbitrary boundary which is considered to represent this horizon.

C. Francken