Patent ID: 8091633
Filing Date: 2012-01-10
Classification: E21B

Abstract:
1. A method of maintaining a wellbore, the wellbore formed through a formation thereby defining a wellbore wall at the wellbore outer periphery, wherein the wellbore includes a lateral wellbore intersecting a primary wellbore, the method comprising: a. disposing a downhole tool into the primary wellbore thereby forming an annulus between the tool and the wall in the primary wellbore, the tool having an acoustic transducer; b. generating an acoustic signal using the transducer, the signal being directed from the tool to the wellbore wall so that when the signal reflects from the wellbore wall a reflection signal is formed, wherein a reflection signal from the wall in the lateral wellbore is identifiable; c. receiving the reflection signal; d. moving the transducer in an axial direction along the wellbore axis; e. repeating steps (b)-(d) to create a collection of received signals; f. identifying a reflection from the wall in the lateral wellbore from the collection of received signals and estimating where the lateral wellbore intersects with the primary wellbore; and g. inserting the downhole tool into a selected lateral wellbore to isolate the primary wellbore from fluids in the selected lateral wellbore.