HR: 0800h
AN: GP41B-0881    [Abstracts]
TI: Crosswell Electromagnetic Imaging for Subsurface Fluid Monitoring
AU: * Alumbaugh, D L
EM: dalumbaugh@slb.com
AF: Schlumberger - EMI Technology Center, 1301 S. 46th St. #300, Richmond, Ca 94804 United States
AU: Wilt, M
EM: mwilt@richmond.oilfield.slb.com
AF: Schlumberger - EMI Technology Center, 1301 S. 46th St. #300, Richmond, Ca 94804 United States
AU: Zhang, P
EM: pzhang1@richmond.oilfield.slb.com
AF: Schlumberger - EMI Technology Center, 1301 S. 46th St. #300, Richmond, Ca 94804 United States
AU: Chen, J
EM: jchen16@slb.com
AF: Schlumberger - EMI Technology Center, 1301 S. 46th St. #300, Richmond, Ca 94804 United States
AU: Denaclara, H
EM: hdenaclara@richmond.oilfield.slb.com
AF: Schlumberger - EMI Technology Center, 1301 S. 46th St. #300, Richmond, Ca 94804 United States
AU: Little, J
EM: little2@bakersfield.oilfield.slb.com
AF: Schlumberger - EMI Technology Center, 1301 S. 46th St. #300, Richmond, Ca 94804 United States
AB: Crosswell electromagnetic imaging is an emerging oilfield technology for mapping the resistivity structure between two wells located tens to hundreds of meters apart. The method employs an electromagnetic dipole source in one well oscillating at 10Hz to 1kHz, and makes measurements of the axial component of the electric or magnetic field in the second well. The use of multiple source and receiver positions within the two wells provides a tomographic data set which after a calibration procedure is inverted using a Gauss-Newton scheme to produce 2D images of electrical conductivity. The images are diagnostic in terms of mapping structure between the two wells, but a more promising use for crosswell EM imaging is time-lapse mapping of changes in fluid content/properties/type, for example, to monitor oil reservoir production or enhanced-oil recovery processes. This paper will describe the basic physics of the method, outline the data processing flow developed by Schlumberger, provide case histories where crosswell EM has been employed in active oil field environment.
DE: 0619 Electromagnetic theory
DE: 0694 Instruments and techniques
DE: 0915 Downhole methods
DE: 6982 Tomography and imaging (7270, 8180)
SC: Geomagnetism and Paleomagnetism [GP]
MN: Fall Meeting 2005