Disappearing plug

Abstract

In an embodiment of the present invention utilizes a frac plug having a large diameter through bore wherein the through bore is at least 75% of the outer diameter of the plug. A tracer assembly is then affixed to a lower end of frac plug. The frac plug tracer assembly is run into a wellbore where the frac plug is then set, perforated, and fracked. The obstruction within the frac plug through bore is then removed. In some instances, the instruction may be a ball, dart, or other obturator and in some instances the obstruction may be a dissolvable plug. With the obstruction within the frac plug through bore removed wellbore fluids from the hydrocarbon formation may flow upward through and around the tracer assembly picking up chemical traces which are then carried to the surface to be analyzed.

What is claimed is: 
     
         1 . A device for placing chemicals within a wellbore comprising,
 a plug having a through bore and a slip about its exterior circumference for gripping the wellbore,   a tracer assembly including a tracer,   wherein the tracer assembly is attached to the plug,   wherein an annular chamber is formed between the exterior circumference of the tracer assembly and the interior circumference of the wellbore,   ports formed through the tracer assembly allowing a fluid to flow between the annular chamber and an interior of the tracer assembly.   
     
     
         2 . The device of  claim 1  wherein, the through bore's internal diameter is at least 75% of the plug's outer diameter. 
     
     
         3 . The device of  claim 1  further comprising, a ball to seal on the through bore. 
     
     
         4 . The device of  claim 1  further comprising, a dissolvable plug within the through bore. 
     
     
         5 . The device of  claim 1  wherein, the tracer assembly includes at least two tracers. 
     
     
         6 . The device of  claim 1  wherein, the tracer is radioactive. 
     
     
         7 . The device of  claim 1  wherein, the tracer is chemical. 
     
     
         8 . A method of placing a tracer the wellbore comprising,
 assembling a plug and tracer assembly,   placing the plug having a through bore and tracer assembly within a wellbore,   sealing the plug and fracking a producing zone,   removing the plug,   entraining a tracer from the tracer assembly into a produced fluid.   
     
     
         9 . The method of  claim 8  wherein, the through bore's internal diameter is at least 75% of the plug's outer diameter. 
     
     
         10 . The device of  claim 8  further comprising, a ball to seal on the through bore. 
     
     
         11 . The device of  claim 8  further comprising, a dissolvable plug within the through bore. 
     
     
         12 . The device of  claim 8  wherein, the tracer assembly includes at least two tracers. 
     
     
         13 . The device of  claim 8  wherein, the tracer is radioactive. 
     
     
         14 . The device of  claim 8  wherein, the tracer is chemical.