Methods and apparatus for locating a lateral wellbore

Abstract

The present invention relates generally to lateral wellbore operations, and more particularly, to downhole tools that include a logging tool for locating a lateral wellbore and associated methods. In some embodiments, the present invention discloses a method for use in lateral wellbore operations that includes entering a lateral wellbore from a primary wellbore with a tool comprising a logging tool, and verifying entry into the lateral wellbore using the logging tool. In yet other embodiments, the present invention discloses methods of locating lateral wellbores from a primary wellbore, and downhole tools that comprise logging tools, such as casing collar locators, radiation detection logging tools, or combinations thereof.

1 . A method for use in lateral wellbore operations, comprising: 
 entering a lateral wellbore from a primary wellbore with a tool comprising a logging tool; and    verifying entry into the lateral wellbore using the logging tool.    
   
   
       2 . The method of  claim 1  wherein the logging tool is a casing collar locator, a radiation detection logging tool, or a combination thereof.  
   
   
       3 . The method of  claim 1  wherein verifying entry into the lateral wellbore comprises: 
 generating a fingerprint of the lateral wellbore using the logging tool; and    comparing the fingerprint of the lateral wellbore with a fingerprint of the primary wellbore and/or a pre-existing fingerprint of the lateral wellbore.    
   
   
       4 . The method of  claim 3  wherein the fingerprint is a collar log, a gamma ray log, or a neutron radiation log.  
   
   
       5 . The method of  claim 3  wherein the fingerprint of the primary wellbore was generated using the logging tool.  
   
   
       6 . The method of  claim 1  further comprising moving the tool in the primary wellbore towards a junction, wherein the lateral wellbore branches from the primary wellbore at the junction.  
   
   
       7 . The method of  claim 6  further comprising positioning the tool at a location anterior to the junction prior to moving the tool towards the junction.  
   
   
       8 . The method of  claim 7  further comprising generating a fingerprint of the primary wellbore using the logging tool while positioning the tool at a location anterior to the junction.  
   
   
       9 . The method of  claim 7  further comprising positioning the tool at a location posterior to the junction prior to positioning the tool at a location anterior to the junction.  
   
   
       10 . The method of  claim 1  further comprising conducting a lateral wellbore operation subsequent to verifying entry into the lateral wellbore.  
   
   
       11 . A method of locating a lateral wellbore of a multilateral well, wherein the multilateral lateral well comprises a primary wellbore and a lateral wellbore that branches from the primary wellbore at a junction, comprising: 
 positioning a tool comprising a logging tool within the multilateral well;    moving the tool within the multilateral well; and    determining whether the tool has entered the lateral wellbore using the logging tool.    
   
   
       12 . The method of  claim 11  wherein determining whether the tool has entered the lateral wellbore comprises comparing a fingerprint generated by the logging tool while moving the tool with a fingerprint of the lateral wellbore and/or a fingerprint of the primary wellbore.  
   
   
       13 . The method of  claim 11  wherein the logging tool is a casing collar locator, a radiation detection logging tool, or a combination thereof.  
   
   
       14 . The method of  claim 11  further comprising generating a fingerprint of the primary wellbore using the logging tool.  
   
   
       15 . The method of  claim 14  wherein the fingerprint is a collar log, a gamma ray log, or a neutron radiation log.  
   
   
       16 . The method of  claim 11  wherein positioning the tool within the multilateral well comprises positioning the tool at a first location in the primary wellbore posterior to the junction.  
   
   
       17 . The method of  claim 16  wherein positioning the tool within the multilateral well further comprises positioning the tool at a second location anterior to the junction subsequent to positioning the tool at the first location in the primary wellbore.  
   
   
       18 . The method of  claim 17  further comprising generating a fingerprint of the primary wellbore while positioning the tool at the second location in the primary wellbore.  
   
   
       19 . The method of  claim 17  wherein moving the tool within the multilateral well comprises moving the tool from the second location in the primary wellbore towards the junction.  
   
   
       20 . The method of  claim 11  further comprising entering the lateral wellbore while moving the tool within the multilateral well.  
   
   
       21 . A method of locating and entering a lateral wellbore from a primary wellbore, wherein the lateral wellbore branches from the primary wellbore at a junction, comprising: 
 (a) positioning a downhole tool in the primary wellbore at a first location posterior to the junction, wherein the downhole tool comprises a casing collar locator;    (b) positioning the downhole tool in the primary wellbore at a second location anterior to the junction subsequent to positioning the downhole tool in the primary wellbore at the first location;    (c) moving the downhole tool from the second location towards the junction; and    (d) determining whether the downhole tool has entered the lateral wellbore using the casing collar locator.    
   
   
       22 . The method of  claim 21  wherein determining whether the downhole tool has entered the lateral wellbore comprises comparing a collar log of the lateral wellbore sensed by the casing collar locator with a collar log of the primary wellbore.  
   
   
       23 . The method of  claim 21  further comprising rotating the downhole tool about a longitudinal axis of the downhole tool subsequent to determining whether the downhole tool has entered the lateral wellbore.  
   
   
       24 . The method of  claim 21  further comprising repeating steps (b) through (d) subsequent to determining whether the downhole tool has entered the lateral wellbore.  
   
   
       25 . The method of  claim 21  wherein the first location is about  100  feet posterior to the junction.  
   
   
       26 . The method of  claim 21  further comprising sensing the location of one or more casing collars in the primary wellbore with the casing collar locator while positioning the downhole tool in the primary wellbore at the second location.  
   
   
       27 . The method of  claim 21  wherein the second location is about 100 feet anterior to the junction.  
   
   
       28 . The method of  claim 21  further comprising deflecting an end of the downhole tool with respect to a longitudinal axis of the downhole tool.  
   
   
       29 . The method of  claim 28  wherein the end of the downhole tool enters the lateral wellbore when the downhole tool passes the junction.  
   
   
       30 . The method of  claim 29  further comprising moving the downhole tool into the lateral wellbore.  
   
   
       31 . The method of  claim 29  further comprising sensing the location of one or more casing collars within the lateral wellbore.  
   
   
       32 . The method  claim 30  further comprising returning the end of the downhole tool to an angle substantially coincident to the longitudinal axis of the downhole tool after the downhole tool moves into the lateral wellbore.  
   
   
       33 . The method of  claim 21  further comprising sensing the location of one or more casing collars within the primary wellbore.  
   
   
       34 . A method of locating and entering a lateral wellbore from a primary wellbore, wherein the lateral wellbore branches from the primary wellbore at a junction, comprising: 
 (a) positioning a downhole tool comprising a radiation detection logging tool in the primary wellbore;    (b) moving the downhole tool towards the junction; and    (c) determining whether the downhole tool has entered the lateral wellbore using the radiation detection logging tool.    
   
   
       35 . The method of  claim 34  wherein determining whether the downhole tool has entered the lateral wellbore comprises comparing a gamma ray log of the lateral wellbore generated using the radiation detection logging tool with a gamma ray log of the primary wellbore and/or a pre-existing gamma ray log of the lateral wellbore.  
   
   
       36 . The method of  claim 34  wherein determining whether the downhole tool has entered the lateral wellbore comprises comparing a neutron radiation log of the lateral wellbore generated using the radiation detection logging tool with a neutron radiation log of the primary wellbore and/or a pre-existing neutron radiation log of the lateral wellbore.  
   
   
       37 . The method of  claim 34  further comprising rotating the downhole tool about a longitudinal axis of the downhole tool subsequent to determining whether the downhole tool has entered the lateral wellbore.  
   
   
       38 . The method of  claim 37  further comprising repeating steps (a) through (c) subsequent to determining whether the downhole tool has entered the lateral wellbore.  
   
   
       39 . The method of  claim 34  further comprising generating a gamma ray log of the primary wellbore while positioning the downhole tool in the primary wellbore.  
   
   
       40 . The method of  claim 34  further comprising generating a neutron radiation log of the primary wellbore while positioning the downhole tool in the primary wellbore.  
   
   
       41 . The method of  claim 34  further comprising deflecting an end of the downhole tool with respect to a longitudinal axis of the downhole tool.  
   
   
       42 . The method of  claim 41  wherein the end of the downhole tool enters the lateral wellbore when the downhole tool passes the junction.  
   
   
       43 . The method of  claim 42  further comprising moving the downhole tool into the lateral wellbore.  
   
   
       44 . The method of  claim 43  further comprising measuring radiation emissions within the lateral wellbore.  
   
   
       45 . The method of  claim 44  wherein the radiation emissions are gamma ray emissions, neutron radiation emissions, or both.  
   
   
       46 . The method  claim 43  further comprising returning the end of the downhole tool to an angle substantially coincident to the longitudinal axis of the downhole tool after the downhole tool moves into the lateral wellbore.  
   
   
       47 . The method of  claim 34  further comprising measuring radiation emissions within the primary wellbore.  
   
   
       48 . A downhole tool, comprising: 
 a logging tool;    a kickover knuckle joint connected to the logging tool; and    a wand connected to the kickover knuckle joint.    
   
   
       49 . The downhole tool of  claim 48  wherein the logging tool is a casing collar locator, a radiation detection logging tool, or a combination thereof.  
   
   
       50 . The downhole tool of  claim 49  wherein the logging tool comprises: 
 a housing;    a fluid passageway for providing fluid communication through the housing; and    a radiation detector positioned within the housing for measuring radiation in a wellbore and for generating a signal corresponding to the measured radiation;    
   
   
       51 . The downhole tool of  claim 50  wherein the radiation detector comprises a gamma ray detector or a neutron detector.  
   
   
       52 . The downhole tool of  claim 50  wherein the logging tool further comprises: 
 a communication unit positioned within the housing;    a control unit positioned within the housing for receiving the signal from the radiation detector and for directing the communication unit to transmit a pressure pulse; and    a battery pack for powering the radiation detector, the control unit, and the communication unit.    
   
   
       53 . The downhole tool of  claim 49  wherein the casing collar locator comprises: 
 a housing;    a fluid passageway for providing fluid communication through the housing; and    a casing collar detector positioned within the housing for sensing the location of one or more casing collars in a wellbore and for generating a signal corresponding to the sensed location.    
   
   
       54 . The downhole tool of  claim 53  wherein the radiation detection logging tool comprises: 
 a communication unit positioned within the housing;    a control unit positioned within the housing for receiving the signal from the casing collar detector and directing the communication unit to transmit a pressure pulse; and    a battery pack for powering the casing collar detector, the control unit, and the communication unit.    
   
   
       55 . The downhole tool of  claim 49  wherein the combination casing collar locator/radiation detection logging tool comprises: 
 a housing;    a fluid passageway for providing fluid communication through the housing;    a casing collar detector positioned within the housing for sensing the location of one or more casing collars in a wellbore and for generating a signal corresponding to the sensed location; and    a radiation detector positioned within the housing for measuring radiation in the wellbore and for generating a signal corresponding to the measured radiation.    
   
   
       56 . The downhole tool of  claim 55  wherein the combination casing collar locator/radiation detection logging tool further comprises: 
 a communication unit positioned within the housing;    a control unit positioned within the housing for receiving the signal from the casing collar detector and the radiation detector, and for directing the communication unit to transmit a pressure pulse; and    a battery pack for powering the casing collar detector, the radiation detector, the control unit, and the communication unit.    
   
   
       57 . The downhole tool of  claim 48  further comprising an orienting sub connected between the logging tool and the kickover knuckle joint.  
   
   
       58 . The downhole tool of  claim 57  wherein the orienting sub includes an indexing tool or a continuously run motor.  
   
   
       59 . The downhole tool of  claim 57  wherein the orienting sub is operated hydraulically.  
   
   
       60 . The downhole tool of  claim 48  wherein the kickover knuckle joint is a selectively activated knuckle joint.  
   
   
       61 . The downhole tool of  claim 48  wherein the kickover knuckle joint is operated hydraulically.  
   
   
       62 . The downhole tool of  claim 48  wherein the wand is adjustable in length.  
   
   
       63 . The downhole tool of  claim 48  wherein the wand includes a nose attached at an end thereof.  
   
   
       64 . The downhole tool of  claim 63  wherein the nose contains one or more ports.  
   
   
       65 . The downhole tool of  claim 48  wherein the wand may be deflected with respect to the longitudinal axis of the downhole tool to a predetermined maximum deflection angle.  
   
   
       66 . The downhole tool of  claim 65  wherein the predetermined maximum deflection angle is in the range of from about 3 degrees to about 30 degrees.