Method for evaluating hydrocarbon-containing subterrean formations penetrated by a directional wellbore

Abstract

A method of evaluating a hydrocarbon-containing subterranean formation to identify potentially productive zones within the formation. The method may be particularly useful for evaluating formations penetrated by at least one directionally drilled wellbore. The method can include releasing, capturing, and measuring at least one property related to the hydrocarbon materials entrapped in rock samples obtained from the formation, and the results of the analysis can be used to perform at least one wellbore-related activity, such as drilling, stimulating, and/or producing a new or existing wellbore.

1 . A method for identifying a productive zone within a hydrocarbon-containing subterranean formation, said method comprising:
 (a) receiving a plurality of rock samples removed from a wellbore penetrating said hydrocarbon-containing subterranean formation, wherein at least a portion of said rock samples comprise entrapped hydrocarbon materials;   (b) reducing the average particle size of at least a portion of said rock samples to thereby release at least a portion of said entrapped hydrocarbon materials;   (c) capturing at least a portion of said entrapped hydrocarbon materials released in step (b);   (d) measuring at least one property of said entrapped hydrocarbon materials captured in step (c) to thereby obtain a set of results; and   (e) organizing said set of results obtained via said measuring of step (d), wherein the organized set of data is used to carry out at least one wellbore-related activity.   
     
     
         2 . The method of  claim 1 , wherein said step (b) includes grinding at least a portion of said rock samples to thereby provide crushed rock samples, wherein said crushed rock samples have a particle size distribution such that at least 25 percent of said crushed rock samples have an average particle size of less than 350 microns. 
     
     
         3 . The method of  claim 1 , wherein said step (b) and said capturing of step (c) are carried out simultaneously. 
     
     
         4 . The method of  claim 1 , wherein said step (d) includes using a hydrocarbon detection or hydrocarbon analysis device to obtain said set of results, wherein said at least one property measured in step (d) relates at least one of the presence, the amount, and the composition of said entrapped hydrocarbon material. 
     
     
         5 . The method of  claim 1 , wherein said step (e) includes creating a visual representation using said set of results, wherein said visual representation is selected from the group consisting of a graph, a table, a log, a map, and a model. 
     
     
         6 . The method of  claim 1 , wherein said at least one wellbore-related activity is selected from the group consisting of continuing to drill said wellbore, drilling one or more new wellbores said subterranean formation, drilling one or more new wellbores into a different subterranean formation, stimulating production of hydrocarbon from said formation, initiating or changing production of hydrocarbon from said wellbore or from one or more other wellbores, and combinations thereof. 
     
     
         7 . The method of  claim 6 , wherein said at least one wellbore-related activity is selectively stimulating production from said wellbore and said wellbore is a directional wellbore having an angle of inclination of at least 40°. 
     
     
         8 . The method of  claim 1 , wherein said plurality of rock samples removed from said wellbore comprise a plurality of drill cuttings obtained during the drilling of said wellbore into said hydrocarbon-containing subterranean formation. 
     
     
         9 . The method of  claim 8 , wherein said subterranean formation is a reservoir rock formation. 
     
     
         10 . The method of  claim 1 , further comprising producing hydrocarbon from said wellbore, wherein at least 75 volume percent of said hydrocarbon produced from said wellbore comprises natural gas and/or natural gas liquids. 
     
     
         11 . A method for producing hydrocarbon from a hydrocarbon-containing subterranean formation, said method comprising:
 (a) drilling a directional wellbore into said hydrocarbon-containing subterranean formation;   (b) obtaining a plurality of rock samples via said wellbore, wherein at least a portion of said rock samples comprise entrapped hydrocarbon materials;   (c) analyzing at least a portion of said rock samples obtained in step (b), wherein said analyzing includes obtaining a set of results related to said entrapped hydrocarbon materials; and   (d) based, at least in part, on said set of results obtained via said analyzing of step (c), performing at least one wellbore-related activity,   wherein said well-bore related activity is selected from the group consisting of continuing to drill said wellbore, drilling one or more new wellbores into said subterranean formation, drilling one or more new wellbores into a different subterranean formation, stimulating production of hydrocarbon from said formation, initiating or changing production of hydrocarbon from said wellbore or from one or more other wellbores, and combinations thereof.   
     
     
         12 . The method of  claim 11 , wherein said directional wellbore has an angle of inclination of at least 50°. 
     
     
         13 . The method of  claim 12 , wherein said step (a) includes utilizing a non-hydrocarbon based drilling fluid and said wellbore-related activity comprises initiating or changing production of hydrocarbon from said wellbore or from one or more other wellbores. 
     
     
         14 . The method of  claim 12 , wherein said subterranean formation comprises a reservoir rock formation and said wellbore-related activity comprises selectively stimulating production of hydrocarbon from said formation. 
     
     
         15 . The method of  claim 11 , wherein said step (c) includes releasing at least a portion of said entrapped hydrocarbon materials from said rock samples, capturing at least a portion of the released hydrocarbon materials, and analyzing at least a portion of the captured hydrocarbon materials with a hydrocarbon detection or hydrocarbon analysis device to thereby provide said set of results. 
     
     
         16 . The method of  claim 15 , wherein said releasing includes grinding at least a portion of said rock samples such that the average size particle size of said rock samples is less than 350 microns, wherein said releasing and said capturing of said entrapped hydrocarbon materials are carried out simultaneously. 
     
     
         17 . The method of  claim 11 , further comprising correlating each of said rock samples obtained in step (b) with a specific physical location within said wellbore or said formation, wherein said physical location is at least partially expressed by total drilled depth. 
     
     
         18 . The method of  claim 11 , wherein said step (c) is carried out at a first location and said steps (a), (b), and (d) are carried out at a second location, wherein said first and said second locations are within about  10  miles of one another. 
     
     
         19 . A method for identifying a productive zone within in a hydrocarbon-containing subterranean formation, said method comprising:
 (a) receiving a plurality of rock samples removed from a wellbore penetrating said hydrocarbon-containing formation, wherein at least a portion of said rock samples comprise entrapped hydrocarbon materials and have a particle size distribution such that less than 20 weight percent of said rock samples have an average particle size less than 350 microns;   (b) grinding at least a portion of said rock samples to provide crushed rock samples, wherein said crushed rock samples have a particle size distribution such that at least 25 weight percent of said crushed rock samples have an average particle size of less than 350 microns;   (c) capturing at least a portion of said entrapped hydrocarbon materials released in step (b);   (d) measuring at least one property of said entrapped hydrocarbon materials captured in step (c), wherein said analyzing includes using a gas detection or gas analysis device to obtain a set of data, wherein said set of data includes one or more values for a property related to said entrapped hydrocarbon materials, wherein said property relates at least one of the presence, the amount, and the composition of said entrapped hydrocarbon materials; and   (e) organizing said set of data obtained via said analyzing of step (d), wherein the organized set of data is used to carry out at least one wellbore-related activity.   
     
     
         20 . The process of  claim 19 , wherein said wellbore is a directional wellbore having an angle of inclination of at least 50° and said well-bore related activity is selected from the group consisting of continuing to drill said wellbore, drilling one or more new wellbores said subterranean formation, drilling one or more new wellbores into a different subterranean formation, stimulating production of hydrocarbon from said formation, initiating or changing production of hydrocarbon from said wellbore or from one or more other wellbores, and combinations thereof. 
     
     
         21 . The process of  claim 19 , wherein each of steps (a) through (e) are carried out at a physical location that is located at least 15 miles from a wellhead of said wellbore.