Patent Number: 6,253,848

Title: Method of obtaining improved geophysical information about earth formations

Abstract: The present invention provides a method for forming wellbores. In one method, one or more wellbores are drilled along preplanned paths based in part upon seismic surveys performed from the surface. An acoustic transmitter conveyed in such wellbores transmits acoustic signals at a one or more frequencies within a range of frequencies at a plurality of spaced locations. A plurality of substantially serially spaced receivers in the wellbores and/or at s receive signals reflected by the subsurface formations. The sensors may be permanently installed in the boreholes and could be fiber optic devices. The receiver signals are processed by conventional geophysical processing methods to obtain information about the subsurface formations. This information is utilized to update any prior seismographs to obtain higher resolution seismographs. The improved seismographs are then used to determine the profiles of the production wellbores to be drilled. Borehole seismic imaging may then be used to further improve the seismographs and to plan future wellbores. Cross-well tomography may be utilized to further update the seismographs to manage the reservoirs. The permanently installed sensors may also be used to monitor the progress of fracturing in nearby wells and thereby provide the necessary information for controlling fracturing operations.

Inventors: Reimers; Nils (Stavanger, NO), Harrell; John W. (Spring, TX), Leggett, III; James V. (Houston, TX), Tubel; Paulo S. (The Woodlands, TX)

Assignee: Baker Hughes Incorporated

International Classification: E21B 49/00 (20060101); E21B 47/10 (20060101); E21B 33/127 (20060101); E21B 33/12 (20060101); E21B 23/00 (20060101); E21B 47/12 (20060101); E21B 49/08 (20060101); E21B 23/03 (20060101); E21B 43/26 (20060101); E21B 47/00 (20060101); E21B 41/00 (20060101); E21B 37/00 (20060101); E21B 37/06 (20060101); E21B 43/16 (20060101); E21B 41/02 (20060101); E21B 43/12 (20060101); E21B 43/20 (20060101); E21B 47/06 (20060101); E21B 47/01 (20060101); E21B 43/38 (20060101); E21B 43/25 (20060101); E21B 43/34 (20060101); G01N 21/31 (20060101); G01V 7/00 (20060101); G01V 7/08 (20060101); G01V 7/16 (20060101); G01V 8/00 (20060101); G01V 8/02 (20060101); G01D 5/26 (20060101); G01V 1/52 (20060101); G01V 1/40 (20060101); G01V 1/46 (20060101); G01V 1/42 (20060101); E21B 047/00 ()

Expiration Date: 07/03/2018