ISOTOPE STRATIGRAPHY IN PETROLEUM EXPLORATION
RENÉ RODRIGUES
Petrobras/Cenpes/Divex/Sebipe, Faculdade de Geologia, UERJ, Rio de Janeiro, RJ.
Presented by ALCIDES N. SIAL
Chemical, physical and biological modification of ocean water in geological time generally produces variations in the concentration, chemistry and isotopic composition of organic matter and carbonate precipitated from this water. Some of these modifications are related to global events and can be considered excellent chronostratigraphic markers.
From such gobal events, the anoxic and glacial events are particularly important in petroleum exploration. The former represents the best environmental conditions for concentration and preservation of organic matter and the later is responsible for glaucioeustatic sea-level fluctuations, which may be regarded as a driving mechanism for turbidite formation. Turbidites comprise the most important oil reservoir of Brazilian offshore sedimentary basins.
The occurrence of anoxic events in geological time can be normally related to positive anomalies in carbon stable isotopic data, whereas the the glacila events are easily defined by relatively abrupt increases of 
O values.
In this study, we report th Stable isotopic signatures of the Cenomanian-Turionian anoxic events in the Sergipe-Alagoas Basin and the Tertiary glaucioeustatic fluctuations in Campos Basin based on oxygen stable isotope data. (May 19, 2000)
Publication Dates
-
Publication in this collection
05 Jan 2001 -
Date of issue
Dec 2000
