The project goal is to use seismic and electrical data from a single borehole to image the fluid content with high resolution out and below a borehole in real time up to 50 meters away.
This project was funded through DOE's Natural Gas and Oil Technology Partnership Program. The Partnership Program establishes alliances that combine the resources and experience of the nation's petroleum industry with the capabilities of the national laboratories to expedite research, development, and demonstration of advanced technologies for improved natural gas and oil recovery.
Lawrence Berkeley National Laboratory (LBNL)
Sandia National Laboratories
This project was spawned by the DeepLook consortium, comprising five major oil companies and several service companies. One effort initiated by the consortium was to use borehole seismic imaging supplemented with electromagnetic (EM) methods, the hypothesis being that the seismic methods will provide information on the structural and mechanical properties of the medium, and the EM measurements will provide independent information on the fluid state from electrical conductivity.
Initial designs and equipment tests have been concluded to combine seismic and electrical tools in the same hole. Noise tests have been performed and target noise levels determined.
This project will fill a gap in the overall industry subsurface imaging effort by providing advanced technology to image fluids at expanded distances from the wellbore. One of the primary needs that this technology will meet is in-situ information for real-time drilling and production decisions with well-log resolution at a distance from the borehole an order of magnitude greater than is available today. Primary application will be in the drilling phase of development, with cost saving provided through more efficient drilling decisions, more accurate drillbit location, and improved reservoir recovery.
Initial work involved setting up parameters for conducting noise tests, then undertaking seismic and EM modeling to confirm the validity of this approach.
Work focused in two areas on the instrumentation side: 1) fabrication, testing, and modification of the LBNL single-well system integration and 2) testing of EM sources with the LBNL system for noise analysis.
In the first area the single-well system was upgraded with new electronics to combine fiber optic telemetry into a more efficient and compact design as well as provide the capability for real-time, remote access to data acquisition for real-time processing and interpretation. An improved single-well source was fabricated and tested that is smaller (3.5 inches vs. 4.25 inches) and higher frequency (1 kHz), yet just as powerful. In the testing and integration of EM components, an EM receiver and electronics package was built and successfully integrated and tested with the LBNL single-well fiber optic system.
In 3-D and EM modeling for validation, sensitivity, and directionality, Sandia National Labs (SNL) focused on specifics to understand reflection and diffraction responses observed by a single-well seismic-data acquisition tool. Earth models represent typical Gulf Coast sedimentary materials. Synthetic seismograms were calculated with an explicit, time-domain, finite-difference algorithm appropriate for 3-D isotropic elastic media. In the EM modeling a new approach was formulated to solve the joint seismic/EM fluid imaging problem-basing it upon the First-Born Approximation in a solution to those equations that encompasses the full physics of seismic and low-frequency EM field propagation in geologic materials.
The next field tests and construction of the EM tools are on hold pending further funding and negotiations with commercial sellers of the technology. Downsizing of seismic sources is still in progress and will enter the next phase this year.
$3,000,000 (70% of total)
Other Government Organizations Involved: Sandia National Laboratories