Volumetric Estimation – A Case History To Explain An Integrated Methodology

This study intends to demonstrate an application<br>of a high-resolution method employed for volumetric<br>estimation in complex reservoirs. The authors used a<br>channelized turbiditic system that make up the<br>Oligocene reservoirs of the offshore Peroá Field,<br>located in the Espirito Santo basin, southeastern Brazil.<br>The focused reservoirs belong to a very complex<br>system of turbiditic channels lying over a main<br>Chattian unconformity. The turbiditic system was<br>built by cut and fill processes produced by a braided<br>subaqueous north- south trending channel system that<br>created an autocyclic pattern over a complete low<br>stand system tract facies.<br>The volumetric estimation employed two very<br>common softwares in the petroleum industry,<br>VoxelGeo from Paradigm Geophysical and<br>Seisworks from Landmark.<br>Both these programs were applied as<br>complementary tools to integrate data and to permit<br>the use of the volumetric estimation method, which,<br>roughly, has the following sequence:<br>(1) Seed detection of reflectors, (2) amplitude<br>extraction, (3) calibration with well logs, (4)<br>construction of grids and maps and (5) a volumetric<br>estimation of individual and associated seismic<br>reservoirs.<br>The application of this technique is useful in the<br>sense of linking exploration tools in order to increase<br>the critical capacity of interpreters to approach areas<br>where complex stratigraphy may occur, such as those<br>where channelized turbiditic fills are present.