The WesternGeco GeoSolutions exploration workflow is based on five steps—illumination, imaging, inversion, integration, and interpretation. The first two steps reside within WesternGeco; the others are shared with the Reservoir Characterization Group and within the customer organization.
Advanced seismic surveys are conducted to provide the correct illumination of complex exploration targets. However, if the seismic energy cannot see the target—and then be reflected back to the surface—the survey has still failed to meet its basic goal. No amount of processing, no matter how advanced, can rectify this failure. The key to success is survey design, and WesternGeco survey design teams have the creativity, geological understanding, and access to the industry’s most advanced acquisition technologies to achieve superior target illumination, however complex the geology.
Illumination studies of the target indicate how successful the survey will be in terms of the ability to examine the target in the data. The second stage is acquiring and then imaging the data. This demands first-class data conditioning and a detailed velocity model to convert seismic time measurements into depths. Here again, WesternGeco is differentiated in the market through its proprietary full-waveform inversion technology, which builds and applies a highly sophisticated model to provide an accurate time-depth conversion that focuses the image for complex exploration prospects.
The next two stages of the WesternGeco GeoSolutions workflow, inversion and integration, benefit from other Reservoir Characterization Group product lines but remain integral to WesternGeco. Inversion is the process for deriving rock, fluid, and pressure information from seismic data. Correctly executing this vital step for characterizing the reservoir requires broadband data, and this quality of data, both on land and offshore. But further information lies within data recorded in the well using wireline logging, logging-while-drilling, and well testing properties.
The integration of all available data within WesternGeco, within the group, and, most importantly, between Schlumberger and the customer is therefore absolutely essential and is achieved through effective data and model sharing via the Petrel platform. The exploration workflow is less and less linear, with iterative stages of model building through all of the first four steps. Increasingly, this cannot be achieved without a strong geological understanding, which demands interpretation skill. Prospect generation is ultimately the job of the customer. But that job is facilitated by the experts from the Data & Consulting Services organization within the Reservoir Characterization Group. Knowledgeable and experienced in geological and geophysical interpretation, they ensure that Schlumberger seismic data and models make sense in the geological context of the exploration target, and that the customer and Schlumberger speak the same technical language.
Next up in the series Many Viewpoints, One Vision: Incorporating Data from the Well…Seismic data shows us the large-scale architecture of a field. From that broad view, WesternGeco GeoSolutions extracts validated distributions of key petrophysical parameters through seismic data inversion, which yields critical information on reservoir continuity and formation parameters across the prospect.
Wireline Field Test Coordinator Adam Walkingshaw is inspecting a side-wall core recovery tool.
This is a continuing series about Schlumberger Reservoir Characterization Group, the leading provider of technology services and products for oil and gas exploration. Articles in the series will address how the Reservoir Characterization Group unites the many disciplines needed to help achieve exploration success.