Method and apparatus for continuous formation sampling and analysis during wellbore drilling

Abstract

A wellbore formation sample acquisition and analysis instrument includes an annular drill bit configured to couple to one end of a drill string. The bit defines a passageway extending from a cutting face thereof to an exterior surface at a longitudinally spaced apart position from the cutting face. The instrument includes at least one sensor configured to measure a selected parameter of a sample of subsurface formation urged into the passageway by action of the cutting face against subsurface formations. Samples of the subsurface formations are ejected from the exterior surface end of the passageway by the samples entering the cutting face end thereof.

1 . A wellbore formation sample acquisition and analysis instrument, comprising:
 an annular drill bit configured to couple to one end of a drill string, the bit defining a passageway extending from a cutting face thereof to an exterior surface at a longitudinally spaced apart position from the cutting face; and   at least one sensor configured to measure a selected parameter of a sample of subsurface formation urged into the passageway by action of the cutting face against subsurface formations, whereby samples of the subsurface formations are ejected from the exterior surface end of the passageway by the samples entering the cutting face end thereof and further wherein an internal diameter of the passageway increases from the cutting face to the exterior surface.   
   
   
       2 . (canceled) 
   
   
       3 . The instrument of  claim 1  wherein the at least one sensor comprises at least one of electrical resistivity sensors, acoustic velocity sensor, density sensor, neutron porosity sensor, neutron capture cross section sensor, natural gamma radiation sensor, neutron activated gamma radiation sensor, imaging sensor and nuclear magnetic resonance relaxometry sensor. 
   
   
       4 . The instrument of  claim 1  wherein the at least one sensor is disposed in a housing releasably coupled to a bit body, the bit body having cutting elements thereon. 
   
   
       5 . The instrument of  claim 4 , wherein the housing comprises a communications couple configured to communicate with a wired drill pipe system. 
   
   
       6 . The instrument of  claim 1  further comprising a telemetry transmitter configured to transmit signals representative of measurements made by the at least one sensor directly or indirectly to the Earth's surface. 
   
   
       7 . The instrument of  claim 6 , wherein the telemetry transmitter comprises a wired drill pipe transmitter. 
   
   
       8 . The instrument of  claim 6 , wherein the telemetry transmitter comprises a mud pulse telemetry. 
   
   
       9 . A method for analyzing subsurface formations, comprising:
 drilling samples of the subsurface formations while drilling a wellbore through the sub surface formations;   analyzing the samples by moving the samples proximate at least one sensor associated with a drill string used to drill the wellbore;   transmitting a measurement related to the samples in substantially real-time to a remote location through at least a portion of the drill string wherein a portion of the drill string comprises wired drill pipe; and   discharging the analyzed samples into an annular space between the drill string and a wall of the wellbore.   
   
   
       10 . The method of  claim 9  wherein the at least one sensor comprises at least one of electrical resistivity sensors, acoustic velocity sensor, density sensor, neutron porosity sensor, neutron capture cross section sensor, natural gamma radiation sensor, neutron activated gamma radiation sensor, imaging sensor and nuclear magnetic resonance relaxometry sensor. 
   
   
       11 . The method of  claim 9  wherein the remote location is the Earth's surface. 
   
   
       12 . The method of  claim 11 , wherein communicating signals from the at least sensor to the Earth's surface comprises transmitting the signals from the at least one sensor via a wired drill pipe. 
   
   
       13 . The method of  claim 11 , wherein communicating signals from the at least sensor to the Earth's surface comprises transmitting the signals from the at least one sensor via mud pulse telemetry. 
   
   
       14 . A wellbore formation sample acquisition and analysis instrument, comprising:
 means for drilling a wellbore;   means for collecting a formation sample;   means for analyzing the formation sample;   means for transmitting data substantially in real-time related to the analysis of the formation sample to the surface through at least a portion of a drill string; and   means for ejecting the formation sample.   
   
   
       15 . The wellbore formation sample acquisition and analysis instrument of  claim 14  wherein at least a portion of the drill string comprises wired drill pipe. 
   
   
       16 . The wellbore formation sample acquisition and analysis instrument of  claim 15  further comprising a continuous passageway extending through a single housing from an annular drill bit to the means for ejecting the formation sample. 
   
   
       17 . The wellbore formation sample acquisition and analysis instrument of  claim 16  wherein the continuous passageway gradually expands in internal diameter from the annular drill bit to the means for ejecting the formation sample. 
   
   
       18 . The wellbore formation sample acquisition and analysis instrument of  claim 14  wherein the means for analyzing the formation sample includes a imaging device. 
   
   
       19 . The wellbore formation sample acquisition and analysis instrument of  claim 9  further comprising transmitting an image of the samples through the portion of the drill string comprising wired drill pipe.