US Patent:
20050211469, Sep 29, 2005
Inventors:
Arthur Kuckes - Ithaca NY, US
John Teer - Dallas PA, US
Assignee:
Vector Magnetics, LLC - Ithaca NY
International Classification:
E21B047/02
Abstract:
An apparatus and method for surveying the path of a borehole includes three single-axis electromagnetic field sensors and three single axis gravity direction sensors in the borehole being surveyed. A pair of closely spaced, parallel guide wires carrying oppositely directed electric current in a reference borehole generate a known electromagnetic field, which is detected by the sensors. Mathematical analysis of electromagnetic and gravity measurements determines the lateral location and the direction of drilling in the neighboring borehole.