Use of MWD assembly for multiple-well drilling

摘要

This invention provides a measurement-while-drilling (MWD) downhole assembly for use in drilling boreholes which utilizes gyroscopes, magnetometers and accelerometers for determining the borehole inclination and azimuth during the drilling of the borehole. With the present invention, a secondary borehole for secondary recovery operations may be drilled with accuracy in proximity to a cased producing borehole.