Unconventional resources such as natural gas in organic-rich shales have become very important exploration and production targets. Shale plays are present in a wide range of geological settings and shale reservoirs have a very large range of compositions, very complex micro-structures and a very variable, vertical nature. Some key controls on shale producibility include richness (TOC-content), thickness, thermal maturity, pore types and brittleness.
Shale reservoir sweet spots are areas that produce noticeable better than other areas. This paper aims to demonstrate the importance of integrating all available data obtained from core measurements, wireline logs and seismic data for identification of production sweet spots within shale plays. The presence, extent, thickness and richness of source rock reservoir sections can be addressed directly from seismic data, based on established relationships between organic content and rock properties derived from analyses of well data. Seismic data also define structural style, depositional architecture, stratigraphic framework and lateral heterogeneities. Stochastically inverted 3D seismic data can be used to predict vertical stacks of predefined lithology classes away from well control. Elastic inversion can be performed to highlight potential reservoir sweet spots as variations in density. Seismic data carefully calibrated to well and core data can be used to characterize key reservoir properties, identification of main target zones for landing lateral wells, improved geo-steering and for quality valuations of fraccing barriers.
Over the last years unconventional resources such as natural oil and gas in organic-rich shales have become very important exploration and production targets. This implies that hydrocarbon source rocks in conventional petroleum systems now have become the reservoir. Our need for being able to predict presence of good shale reservoirs away from well control has resulted in increased focus on reservoir properties which can be extracted from seismic data.
This presentation aims to demonstrate the importance of integrating all available data from core measurements, wireline logs and seismic data for identification of production sweet-spots within shale plays. The presentation is focused on:
to demonstrate why conventional seismic data can be used to predict source rock parameters and
to demonstrate how seismic data quality impacts the confidence in the predictions made from seismic data.