WELL RANGING APPARATUS, SYSTEMS, AND METHODS

摘要

Disclosed embodiments include apparatus, systems, and methods which operate to include monitoring an electromagnetic signal and/or gamma ray spectra count values to determine interception of a first well created by a drill string, with a well casing surrounding a second well. Interception can be determined when a reception antenna is used to receive the electromagnetic signal, by examining values associated with the magnitude of the signal. Interception can also be determined when a ratio of the gamma ray spectra count values have exceeded a first predetermined threshold, or when capture gamma energy indicated by the gamma ray spectra count values exceeds a second predetermined threshold. Additional apparatus, systems, and methods are disclosed.

主权项

1. A system, comprising:
a transmitter comprising a transmission antenna or a current source to couple to a well casing or a tool housing in a drill string, and a reception antenna mechanically coupled to the drill string, wherein the transmitter is to provide an electromagnetic signal to the reception antenna; and an interception determination module to monitor the electromagnetic signal received by the reception antenna, and to determine interception of a casing surrounding a second well by a first well, by examining values associated with a magnitude of the electromagnetic signal obtained during rotation of the drill string within the first well, or obtained at multiple depths within the first well.