IAMG 2001--Cancún Technical Program--Session J

Home Page Technical Program Session J Intro Session J Papers

Stratigraphic Relations of Area and Volume in Petroleum Reservoirs in Rift Basins by Hernani Aquini Fernandes Chaves, University of the State of Rio de Janeiro, Brazil Marginal sedimentary basins in the Northeastern part of Brazil are characterized by a Late Paleozoic sedimentation followed by rift basins sedimentation and a marine sedimentation in those basins in the eastern border of the country. The rifting and marine sedimentation are associated with the opening of South Atlantic Ocean, started during the Early Cretaceous. More than 70 oil and gas fields located in seven of the rift basins were analyses for the covariance of their volume of original oil equivalent in place and its horizontal projection areas. The basins are Potiguar Basin, in Rio Grande do Norte State, the Sergipe/Alagoas Basin in the states of same name, the Reconcavo and Tucano Basin in State of Bahia, and Espirito Santo/Mucuri Basin in the State of Espirito Santo. The relation between horizontal projected area (ring fence) of a petroleum accumulation and the its original oil equivalent volume is well known. In fact it is a quite obvious relation since it is not possible to increase a volume, a three dimensional entity without the corresponding increment in the three dimension that makes it. It is important, however, to identify the differences due to different basins and to depth in the same basin whenever we have real data to analyze, in order to be able to use these data in the appraisal of the potential of undiscovered petroleum accumulation in other sedimentary basins. Paper in PDF format Chaves, Acrobat PDF, 700 k.