Remotely operated selective fracing system and method

1. A selectively-actuatable fracing valve comprising:

a generally-cylindrical casing having at least one casing hole;

a generally-cylindrical inner sleeve nested within said casing and having at least one sleeve hole alignable with said at least one casing hole;

actuator means for moving said inner sleeve relative to said casing and selectively aligning said at least one sleeve hole with said at least one casing hole; and

receiver means electrically connected to said actuator means for detecting mechanical energy generated by a seismic source and converting said mechanical energy into an electrical signal;

said inner sleeve has at least one seating bore disposed therein; and

said actuator means comprises:

a compression spring urging said inner sleeve linearly within said casing; and

a solenoid-and-cam assembly affixed to said casing and having a cam follower pin insertable into said at least one seating bore.

2. The fracing valve of claim 1 wherein said receiver means includes a sensor selected from the group consisting of a geophone and a hydrophone.

3. A remotely-operated selective fracing system comprising:

at least one selectively-actuatable fracing valve, said valve comprising:

a generally-cylindrical casing having at least one casing hole;

a generally-cylindrical inner sleeve nested within said casing and having at least one sleeve hole alignable with said at least one casing hole;

actuator means engagable with said inner sleeve for moving said inner sleeve relative to said casing and selectively aligning said at least one sleeve hole with said at least one casing hole; and

receiver means electrically connected to said actuator means for detecting mechanical energy generated by a seismic source and converting said mechanical energy into an electrical signal;

said inner sleeve has at least one seating bore disposed therein; and

said actuator means comprises:

a compression spring urging said inner sleeve linearly within said casing; and

a solenoid-and-cam assembly affixed to said casing and having a cam follower pin insertable into said at least one seating bore; and

source means for generating an acoustical signal receivable by said receiver means.

4. The system of claim 3 wherein said source means comprises a seismic source.

5. The system of claim 4 wherein said seismic source is selected from the group consisting of accelerated weight drop, an air gun, vibroseis, and dynamite detonation.

6. The system of claim 4 wherein said source means further comprises:

a decoder in communication with said seismic source; and

an encoder in communication with said decoder.

7. A method of remotely actuating a selectively actuatable fracing valve having a generally-cylindrical inner sleeve nested within a casing, said method comprising:

generating an encoded signal receivable by receiver means of said valve;

receiving said signal at said valve;

selectively actuating said valve;

applying an expansive force to said sleeve;

resisting movement of said sleeve urged by said expansive force with a cam follower pin disposed into a first seating bore disposed in said sleeve;

removing said pin from said first seating bore; and

disposing said pin into a second seating bore disposed in said sleeve.

8. The method of claim 7 wherein said encoded signal is acoustic and said generating step comprises causing a series of acoustic signals according to a predetermined communication protocol.

9. The method of claim 7 wherein said encoded signal is electromagnetic and said generating step comprises transmitting said signal through the earth.

10. The method of claim 7 wherein said encoded signal is electromagnetic and said generating step comprises transmitting said signal through a production well casing.

11. The method of claim 7 wherein said encoded signal is electromagnetic and said generating step comprises pumping a control ball into a production well, said control ball being capable of emitting said signal from within said production well.