Detecting acoustic signals from a well system

Abstract

A heated fluid injection string ( 106 ) injects heated treatment fluid into a well ( 102 ) in a subterranean zone ( 112 ) and generates an acoustic signal. An acoustic detector ( 212 ) detects the acoustic signal, and an acoustic signal analyzer ( 214 ) interprets the detected acoustic signal. In some implementations, the acoustic signal analyzer ( 214 ) interprets the detected acoustic signal to determine information about at least one of the heated fluid injection string ( 106 ), the well ( 102 ), or the subterranean zone ( 112 ).

1 . A system, comprising:
 a heated fluid injection string that injects heated treatment fluid into a well in a subterranean zone and generates an acoustic signal;   an acoustic detector that detects the acoustic signal; and   an acoustic signal analyzer that interprets the detected acoustic signal.   
     
     
         2 . The system of  claim 1 , wherein the acoustic signal analyzer interprets the detected acoustic signal to determine information about at least one of the heated fluid injection string, the well, or the subterranean zone. 
     
     
         3 . The system of  claim 2 , wherein the determined information comprises information related to at least one of description of the subterranean formation, integrity of the well, or operation of the fluid injection string. 
     
     
         4 . The system of  claim 3 , wherein the information related to description of the subterranean formation comprises information related to at least one of a location of a fluid interface or a movement of a fluid interface. 
     
     
         5 . The system of  claim 3 , wherein the information related to integrity of the well comprises information related to at least one of a leak in a component of the well, a leak in a tool installed in the well, a flow obstruction in the well, or a flow obstruction in a tool installed in the well. 
     
     
         6 . The system of  claim 3 , wherein the information related to operation of the fluid injection string comprises information related to at least one of an air to fuel ratio, a combustion temperature, a combustion efficiency, or a fluid composition. 
     
     
         7 . The system of  claim 3 , further comprising a controller configured to modify at least one aspect of operation of the fluid injection string based on the information provided by the acoustic signal analyzer. 
     
     
         8 . The system of  claim 1 , wherein the fluid injection string comprises at least one of a fluid oscillator device, a whistle, or a horn. 
     
     
         9 . The system of  claim 1 , wherein the acoustic detector comprises a plurality of sensors installed in a plurality of different locations. 
     
     
         10 . The system of  claim 1 , wherein the acoustic detector comprises at least one of a sensor installed in the well, a sensor installed at a terranean surface, or a sensor installed in a different well. 
     
     
         11 . The system of  claim 1 , wherein the acoustic detector comprises at least one sensor installed directly on at least one component of the fluid injection string. 
     
     
         12 . The system of  claim 1 , wherein the fluid injection string comprises a steam generator installed in the well. 
     
     
         13 . A method, comprising:
 detecting an acoustic signal generated in connection with injecting heated treatment fluid into a well in a subterranean zone; and   interpreting the detected acoustic signal.   
     
     
         14 . The method of  claim 13 , further comprising determining information about at least one of the heated treatment fluid injecting or the subterranean zone based at least in part on the interpretation of the detected acoustic signal. 
     
     
         15 . The method of  claim 13 , further comprising injecting the heated treatment fluid into the well during a plurality of time periods to generate the detected acoustic signals. 
     
     
         16 . The method of  claim 13 , wherein interpreting the detected acoustic signal comprises identifying a property of the detected acoustic signal, the property comprising at least one of amplitude, phase, or frequency. 
     
     
         17 . The method of  claim 13 , further comprising modifying operation of a tool installed in the well based at least in part on the detected acoustic signal. 
     
     
         18 . The method of  claim 13 , wherein interpreting the detected acoustic signal comprises identifying a rising edge of an acoustic signal generated by a fluid oscillator device. 
     
     
         19 . The method of  claim 13 , wherein detecting the acoustic signal comprises detecting an acoustic signal generated by at least one of a steam generator, a fluid oscillator, a whistle, or a horn. 
     
     
         20 . The method of  claim 13 , wherein detecting the acoustic signal comprises detecting a primary acoustic signal and a secondary acoustic signal. 
     
     
         21 . The method of  claim 13 , wherein detecting the acoustic signal comprises at least one of detecting a reflected acoustic signal or detecting a transmitted acoustic signal. 
     
     
         22 . The method of  claim 13 , wherein the acoustic signal comprises a first acoustic signal, the method further comprising:
 detecting a second acoustic signal; and   interpreting the detected second acoustic signal   
     
     
         23 . The method of  claim 22 , further comprising identifying movement of a fluid interface in the subterranean zone based at least in part on the interpretation of the first acoustic signal and the interpretation of the second acoustic signal. 
     
     
         24 . The method of  claim 22 , wherein identifying movement of a fluid interface comprises identifying movement of a steam front. 
     
     
         25 . The method of  claim 22 , further comprising comparing properties of the first acoustic signal to properties of the second acoustic signal. 
     
     
         26 . The method of  claim 22 , further comprising identifying differences between the first acoustic signal and the second acoustic signal. 
     
     
         27 . The method of  claim 22 , wherein the first acoustic signal is detected during a first time period and the second acoustic signal is detected during a second time period after the first time period. 
     
     
         28 . The method of  claim 22 , wherein the first acoustic signal and the second acoustic signal are detected during the same time period. 
     
     
         29 . The method of  claim 22 , wherein the first acoustic signal comprises a first set of frequencies and the second acoustic signal comprises a second set of frequencies not included in the first set of frequencies. 
     
     
         30 . The method of  claim 22 , wherein the first acoustic signal is detected at a first location and the second acoustic signal is detected at a second location. 
     
     
         31 . A system comprising:
 a fluid injection string that generates an acoustic signal in connection with injection of heated treatment fluid into a well in a subterranean zone;   an acoustic detector that detects the acoustic signal; and   an acoustic signal analyzer that interprets the detected acoustic signal.   
     
     
         32 . The system of  claim 31 , wherein the acoustic signal analyzer interprets the detected acoustic signal to determine information about at least one of the fluid injection string, the well, or the subterranean zone. 
     
     
         33 . The system of  claim 31 , wherein the fluid injection string comprises a fluid oscillator device that includes an interior surface defining an interior volume of the fluid oscillator device, an inlet into the interior volume, and an outlet from the interior volume, the interior surface being static during operation to receive the heated treatment fluid into the interior volume through the inlet and to vary over time a flow rate of the heated treatment fluid from the interior volume through the outlet. 
     
     
         34 . The system of  claim 33 , wherein the fluid injection string further comprises an additional fluid oscillator device and a valve to selectively communicate the heated treatment fluid to at least one of the fluid oscillator device or the additional fluid oscillator device. 
     
     
         35 . The system of  claim 34 , wherein the fluid oscillator device comprises a first steam whistle configured to generate an acoustic signal comprising a first range of frequencies and the additional fluid oscillator device comprises a second steam whistle configured to generate an acoustic signal comprising a second range of frequencies. 
     
     
         36 . The system of  claim 34 , further comprising a bypass conduit, the valve to selectively communicate the heated treatment fluid to at least one of the fluid oscillator device, the additional fluid oscillator device, or the bypass conduit.