Patent ID: 9022144
Filing Date: 2015-05-05
Classification: E21B,G01V

Abstract:
1. A drill bit assembly for measuring reservoir formation properties, comprising an electrically conductive bit head having a cutting end and an opposite connecting end with an engagement section; an electrically conductive pin body comprising a connecting end with an engagement section, the pin body connecting end positioned relative to the bit head connecting end such that the engagement sections overlap with a gap therebetween; an electrically insulating gap joint filling the gap between the bit head and pin body engagement sections such that the bit head and pin body are mechanically connected together at the connecting ends but electrically separated; an electrical conductor electrically connected at a first end to the bit head and communicable at a second end with an alternating current signal to transmit an alternating current into the bit head, thereby inducing an electric current into a reservoir formation adjacent the bit head, and electronic equipment including measurement circuitry configured to determine the alternating current at the bit head, the alternating current being inversely proportional to a bit resistivity of the formation, wherein the electronic equipment further includes a switch electrically coupled to the conductor and switchable between EM telemetry circuitry wherein the bit head serves as an EM telemetry antenna, and the measurement circuitry wherein the bit head serves as an electrode for measuring formation properties.