Today’s exploration and production demands require not only that we sharpen existing tools but that we incorporate new technology such as multicomponent methods as we seek to gain important subsurface information. For example, although P-wave data provide good structural images of the subsurface, there is an increasing need to move beyond such images and understand issues such as pore fluids and their movement, rock types, porosity, permeability, stratigraphy and fracture geometry/intensity. Information derived from P-wave data is often insufficient in addressing these and other issues. P- and S-waves respond differently to fluid and solid combinations in the subsurface and their joint use can provide more complete information about rock properties.



CGGVeritas recognized very early on the importance of multicomponent technology in addressing a broad range of exploration and production challenges. For example, over the past few years, CGGVeritas land crews have acquired around 150 multicomponent surveys in North and South America and the Middle East utilizing Sercel DSU 3C MEMS-technology sensors. Land 3C data acquisition projects can often be executed at a very modest increase in cost, when conditions allow the use of one MEMS sensor at each receiver location.



The value provided by using multicomponent data lies in the more complete knowledge of subsurface bulk rock properties and reservoir conditions. P- and S-waves possess different sensitivities to the elastic wavefield parameters which change due to lithology, porosity, presence of fractures, fluid composition, pore pressure and local stress fields. In practice, the conventional P-wave image will carry the primary reservoir geometry information (structure, faulting) while the combined analysis of P- and S-waves provide the specific attributes necessary to demarcate optimum reservoir conditions. Applications include delineating low P-wave impedance sands encased in shales, fracture detection in carbonates and ascertaining gas- vs. brine-filled sands using P and S information. Exploration and Production risk is reduced by having more complete information.



This translates directly to more effective drilling programs where costs often significantly outweigh seismic expenditures. Additionally, more complete subsurface information can reduce total project duration, allowing the client’s exploration and development staff to work more projects.



CGGVeritas professionals can collaborate on projects to help ensure that maximum value is extracted from the use of multicomponent information. We work with the client from initial feasibility studies based on the rock property conditions specific to the reservoir problem through multicomponent data acquisition design and 3C/4C acquisition operations. We offer integrated P- and S-wave processing and interpretation, delivering P-wave and S-wave images and attribute volumes into the client’s interpretation project workflow. Our experienced multicomponent specialists work with client geoscientists to register the P- and S-wave images, extracting the best possible elastic wave information for their reservoir problem.



Recognizing the importance of multicomponent methods, CGGVeritas continues to invest heavily in technological growth in all phases of multicomponent operations – acquisition, processing and interpretation. Our company provides a full range of services to help oil and gas companies assess the applicability of multicomponent data for their projects and to develop full value from the use of this data.


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