Lower Cretaceous Palynostratigraphy, organic sedimentology and evolution of the Maracaibo Basin, western Venezuela. Omar Colmenares, 1994. A thesis submitted in the conformity with the requirements for the Degree of Doctor of Philosophy Department of Geology in the University of Toronto, Canada, 1994. You can download complete PDF version at / Puedes bajar la versión completa en PDF en: https://mariantoc.github.io/stratigraphy.html#ColmenaresO1994