Petrophysical and seismic properties of lower Eocene clastic rocks in the central Maracaibo Basin

摘要

High-resolution, well-log cross sections are used to map the continuity of hydrocarbon-bearing sandstone reservoirs in the Centro Lago fields, central Maracaibo Basin, Venezuela. Because most sandstone reservoirs are below the limit of seismic resolution, reservoir mapping relies on detailed well-log correlations. Seismic data are used mainly to define the structural framework. A feasibility analysis based on the correlation of seismic data and petrophysical properties of Eocene clastic rocks was conducted to demonstrate that lithology and fluid content can be differentiated by acoustic impedance known from well-log data. However, low vertical resolution of the three-dimensional seismic data made available for this study (25 Hz dominant frequency) is not adequate to constrain the lateral and vertical continuity of the Eocene reservoirs.