Offshore exploration and production companies are always looking for ways to improve well placement, monitor production pressures, and get the most out of their tapped reservoirs. Fortunately, technological advances in evaluating, monitoring, and extending reservoir viability are giving offshore oil and gas new tools for success. This includes a bevy of geological interpretation tools, seismic sensors, and advanced subsea compressors.
When it comes to evaluating and monitoring a reservoir, geological interpretation tools are advancing what we can do with a wide variety of reservoir types. SEAM Corporation’s SEG Advanced Modeling (SEAM) and their associated SEAM Pressure Prediction project represent one example of such advances. These and other associated SEAM projects aim to improve “seismic acquisition, processing, and imaging” modalities and improve how we predict and monitor reservoir pressure. By making more accurate predictions of reservoirs and then verifying those predictions with monitoring technology, seismic imaging is doing a lot to improve well placement and production.
Reservoir monitoring and control tools are also enhancing the budding field of permanent reservoir monitoring (PRM). In an October 2014 article in Oil & Gas Journal, Author Rocco Detomo, Jr. outlined three such technologies buoying PRM: subsea seismic systems, geodesic instrumentation, and downhole fiber optic sensors. Subsurface velocity and density changes can be measured with seismic-based ocean-bottom nodes (OBNs) throughout early development, production, and end-of-life, ensuring better well placement and providing a look at “bypassed reserves or remaining opportunities” nearby. Lateral seafloor movement and subsidence can be better monitored and predicted through an emerging system of integrated geophysical meters, sensors, and recorders that can measure pressure, ranging, and gravitational forces. Finally, distributed acoustic sensing (DAS), composed of a passive chain of tiny sensors placed unobtrusively in well casing or tubing, measures wellbore performance and helps provide vertical seismic profiles (VSPs) of the reservoir. Combined, these technologies promise to improve reservoir recovery efficiency and enhance access to difficult-to-reach reserves.
While reservoir evaluation and monitoring technologies have the potential to improve reservoir recovery, extending the longevity of a reservoir is also useful. One way to extend production at a reservoir is to maintain or improve reservoir pressure, which tends to decrease over time. The technology to do that is evolving and changing as demand changes. For example, as offshore exploration and production becomes even more sophisticated with advances in subsea structures, subsea compression technology must grow up around it. German company MAN Diesel & Turbo is one of several companies that have answered the call, having recently developed a motor-compressor able to withstand 220 bar pressure and provide emission- and maintenance-free operation from the sea floor. “This technology represents a quantum leap for the entire oil and gas industry,” MAN CEO Uwe Lauber told PennEnergy.