Method and device for sealing boreholes

Abstract

A device and method for sealing boreholes. Typically, a seismic test hole is sealed by covering a topping plug with water expansible material, such as bentonite, which seals the hole once it expands on exposure to water or moisture. The present invention provides a method and a device for sealing seismic holes, the device comprising a generally tubular water permeable sleeve filled with water expansible aggregate.

1 . A device for sealing a borehole comprising: 
 a generally tubular water permeable sleeve, said sleeve being closed at both ends, and water expansible aggregate, said aggregate located within and contained by the sleeve, said sleeve generally of a size and stiffness to maintain its shape when filled with said water expansible aggregate to permit insertion into a borehole and allow expansion of its contents on exposure to water.    
     
     
         2 . A device for sealing a borehole according to  claim 1  wherein said sleeve is mesh.  
     
     
         3 . A device for sealing a borehole according to  claim 2  wherein said mesh sleeve is made of polypropelene.  
     
     
         4 . A device for sealing a borehole according to  claim 1  wherein said aggregate is bentonite.  
     
     
         5 . A device for sealing a borehole according to  claim 2  wherein said aggregate is bentonite.  
     
     
         6 . A device for sealing a borehole according to  claim 3  wherein said aggregate is bentonite.  
     
     
         7 . A device for sealing a borehole according to  claim 1  wherein at least one end of said sleeve is closed using a metal fastener.  
     
     
         8 . A device for sealing a borehole according to  claim 2  wherein at least one end of said sleeve is closed using a metal fastener.  
     
     
         9 . A device for sealing a borehole according to  claim 3  wherein at least one end of said sleeve is closed using a metal fastener.  
     
     
         10 . A device for sealing a borehole according to  claim 4  wherein at least one end of said sleeve is closed using a metal fastener.  
     
     
         11 . A device for sealing a borehole according to  claim 5  wherein at least one end of said sleeve is closed using a metal fastener.  
     
     
         12 . A device for sealing a borehole according to  claim 6  wherein at least one end of said sleeve is closed using a metal fastener.  
     
     
         13 . A method for sealing a borehole using the device of  claim 1  consisting of: 
 plugging the hole with a topping plug;  
 sliding said device into said borehole; and  
 exposing said device to water;  
 whereby said aggregate matter expands and seals the hole on exposure to water.  
 
     
     
         14 . A method according to  claim 13  whereby more than one device is slid into the borehole.