Abstract: Geochemical Study of the Organic Matter from Querecual Formation, Anzoategui State, Venezuela
G. Garban, L. Lopez, S. Lo Monaco, A. Lira
Kerogen and bitumen fractions extracted from twenty-one limestone samples from kind section of Querecual formation (Querecual River, Anzoategui State, Venezuela) were analyzed for their content of Co, Cr, Fe, Mn, Mo, Ni, S, Sr, V and Zn. S and trace-metals content from the kerogen fraction were used to obtain information about paleoenvironmental sedimentation conditions of the Querecual formation. Based on these data, and especially on the V and S content variations plus V/Ni, V/V+Ni and Mo/Mo+Cr ratios, we confirm an ancient-reducer condition on this region according with a sulfur-reducer environment. Trace-metals content variations from the bitumen fraction along the study section were used as possible primary migration indicators. V and Ni were the only elements showin a clear tendency to be used as primary migration indicators. The observed tendency allows us to postulate a vertical migration of the bitumen, from center to the extremes of the section.
AAPG Search and Discovery Article #90951©1996 AAPG International Conference and Exhibition, Caracas, Venezuela