Reservoir communication with a wellbore

A method for use in a wellbore, comprising:

• lowering a tool string having a first chamber into the wellbore proximal a formation;
• activating at least one explosive element to open communication with the chamber to create an underbalance condition in the wellbore proximal the formation;
• activating a perforating gull in the tool string once the underbalance condition is created;
• opening communication with a second chamber in the tool string to create a fluid flow surge from the formation into the second chamber;
• and
• providing activation commands from the surface to control opening of communication with the first and second chambers.

A method for use in a wellbore, comprising:

• lowering a tool string having a first chamber into the wellbore proximal a formation;
• activating at least one explosive element to open communication with the chamber to create an underbalance condition in the wellbore proximal the formation;
• activating a perforating gun in the tool string once the underbalance condition is created;
• opening communication with a second chamber in the tool string to create a fluid flow surge from the formation into the second chamber;
• and
• releasing the perforating gun before opening communication with the second chamber.

A method for use in a wellbore, comprising:

• lowering a tool string having a first chamber into the wellbore proximal a formation;
• activating at least one explosive element to open communication with the chamber to create an underbalance condition in the wellbore proximal the formation;
• opening communication with a second chamber in the tool string to create a fluid flow surge from the formation into the second chamber;
• and
• injecting the fluid in the second chamber back into the formation.

A tool string for use in a wellbore, comprising:

• a container including a first chamber at a predetermined low pressure;
• one or more ports to enable communication with the first chamber to create an underbalance condition in the wellbore;
• at least one explosive element adapted to open the one or more ports;
• and
• a second chamber to receive a surge of fluid from a formation, wherein the second chamber has a volume larger than the first chamber, the second chamber being at a predetermined low pressure.

A method for use in a wellbore comprising:

• providing an assembly having at least a first chamber and a second chamber;
• activating communication with the first chamber to create an underbalance condition in the wellbore;
• activating communication with the second chamber to create a fluid flow surge from a formation surrounding the wellbore;
• operating a tool in the underbalance condition;
• and
• releasing the tool before activating communication with the second chamber.

A method for use in a wellbore comprising:

• providing an assembly having at least a first chamber and a second chamber;
• activating communication with the first chamber to create an underbalance condition in the wellbore;
• activating communication with the second chamber to create a fluid flow surge from a formation surrounding the wellbore;
• and
• injecting fluid from the second chamber back into the formation.