Downhole anomaly localization and interpretation using acoustic and electromagnetic logging

Abstract

Disclosed are systems and methods for detecting a downhole anomaly. The method can include receiving one or more acoustic measurements at a plurality of corresponding depths in a casing, determining a presence of a flow at one or more flow depths, receiving one or more electromagnetic measurements at each of the one or more flow depths in the casing, determining an integrity of the casing at each of the one or more flow depths in the casing, and determining a presence or absence of a leak at each of the one or more flow depths in the casing based on the integrity of the casing at each of the one or more flow depths.

What is claimed is: 
     
         1 . A method for detecting a downhole anomaly, the method comprising:
 deploying an acoustic tool and an electromagnetic tool downhole;   receiving, via the acoustic tool, one or more acoustic measurements within and/or around a casing at a plurality of corresponding depths;   determining, based on the one or more acoustic measurements, a presence of a flow at one or more flow depths of the plurality of corresponding depths in the casing, wherein the presence of the flow indicates that there is flow behind the casing or a leak in the casing;   receiving, via the electromagnetic tool, one or more electromagnetic measurements within and/or around the casing at each of the one or more flow depths;   determining, based on the one or more electromagnetic measurements, an integrity of the casing at each of the one or more flow depths in the casing; and   determining, based on the integrity of the casing at each of the one or more flow depths, a presence or absence of a leak at each of the one or more flow depths in the casing.   
     
     
         2 . The method of  claim 1 , wherein the acoustic tool includes a hydrophone array. 
     
     
         3 . The method of  claim 1 , wherein determining the presence of the flow includes utilizing a beamforming method to determine a position of the one or more flow depths in the casing. 
     
     
         4 . The method of  claim 3 , wherein the position includes a vertical position and radial position of the flow. 
     
     
         5 . The method of  claim 1 , wherein the electromagnetic tool includes at least one transmitter station having at least one transmitter coil and at least one receiver station having at least one receiver coil. 
     
     
         6 . The method of  claim 5 , wherein the at least one transmitter coil is operable to induce eddy currents in one or more well tubulars and the at least one receiver coil is operable to measure a magnetic field generated at least in part by the eddy currents. 
     
     
         7 . The method of  claim 6 , wherein the at least one receiver coil is operable to determine a thickness of the one or more well tubulars and/or a thickness of the casing. 
     
     
         8 . The method of  claim 1 , wherein the electromagnetic tool is operable to determine a vertical position and/or an azimuthal position at the one or more flow depths in the casing. 
     
     
         9 . The method of  claim 1 , wherein the integrity of the casing comprises a degree of metal loss. 
     
     
         10 . The method of  claim 1 , wherein the presence of the leak is determined when the integrity of the casing is determined to show metal loss. 
     
     
         11 . The method of  claim 1 , wherein the absence of the leak is determined when the integrity of the casing is determined to show no metal loss. 
     
     
         12 . A system for detecting a downhole anomaly, the system comprising:
 an acoustic tool;   an electromagnetic tool;   at least one processor; and   a memory coupled to the at least one processor having instructions stored therein, which when executed by the at least one processor, cause the at least one processor to perform a plurality of functions, including functions to:   receive, via the acoustic tool, one or more acoustic measurements within and/or around a casing at a plurality of corresponding depths;   determine, based on the one or more acoustic measurements, a presence of a flow at one or more flow depths in the casing, wherein the presence of the flow indicates that there is flow behind the casing or a leak in the casing;   receive, via the electromagnetic tool, one or more electromagnetic measurements within and/or around the casing at the one or more flow depths;   determine, based on the one or more electromagnetic measurements, an integrity of the casing at the one or more flow depths in the casing; and   determine, based on the integrity of the casing at the one or more flow depths, a presence or absence of a leak at the one or more flow depths in the casing.   
     
     
         13 . The system of  claim 12 , wherein the acoustic tool includes a hydrophone array. 
     
     
         14 . The system of  claim 12 , wherein determining the presence of the flow includes utilizing a beamforming method to determine a position of the one or more flow depths in the casing. 
     
     
         15 . The system of  claim 14 , wherein the position is a vertical position and a radial position of the flow. 
     
     
         16 . The system of  claim 12 , wherein the electromagnetic tool includes at least one transmitter station having at least one transmitter coil and at least one receiver station having at least one receiver coil. 
     
     
         17 . The system of  claim 16 , wherein the at least one transmitter coil is operable to induce eddy currents in one or more well tubulars and the at least one receiver coil is operable to measure a magnetic field generated at least in part by the eddy currents. 
     
     
         18 . The system of  claim 17 , wherein the at least one receiver coil is operable to determine a thickness of the one or more well tubulars and a thickness of the casing. 
     
     
         19 . The system of  claim 12 , wherein the electromagnetic tool is operable to determine a vertical position and/or an azimuthal position at the one or more flow depths in the casing. 
     
     
         20 . The system of  claim 12 , wherein the presence of a leak is determined when the integrity of the casing is determined to show metal loss.