The contracts include the joint ventures Petroboscan and Petropiar, officials said, but details were not disclosed. The documents were signed at PDVSA's Caracas headquarters by minister Tareck El Aissami, Chevron's President for Venezuela, Javier La Rosa, and PDVSA's president Asdrubal Chavez.

(Reporting by Deisy Buitrago; Editing by Gary McWilliams)