System for fracturing an underground geologic formation

Patent metadata

Field	Value
Publication number	US-10329890-B2
Application number	US-201715421077-A
Country	US
Kind code	B2
Filing date	Jan 31, 2017
Priority date	Jan 13, 2012
Publication date	Jun 25, 2019
Grant date	Jun 25, 2019

Abstract

An explosive system for fracturing an underground geologic formation adjacent to a wellbore can comprise a plurality of explosive units comprising an explosive material contained within the casing, and detonation control modules electrically coupled to the plurality of explosive units and configured to cause a power pulse to be transmitted to at least one detonator of at least one of the plurality of explosive units for detonation of the explosive material. The explosive units are configured to be positioned within a wellbore in spaced apart positions relative to one another along a string with the detonation control modules positioned adjacent to the plurality of explosive units in the wellbore, such that the axial positions of the explosive units relative to the wellbore are at least partially based on geologic properties of the geologic formation adjacent the wellbore.

First claim

The invention claimed is:

1. A system for fracturing an underground geologic formation adjacent to a wellbore, comprising:
a plurality of explosive units comprising a casing, a detonator, and an explosive material contained within the casing, the explosive material configured to release a total energy upon detonation and with greater than 30% of the energy released by the explosive material being released in a following flow Taylor Wave; and
one or more detonation control modules electrically coupled to the plurality of explosive units, each detonation control module comprising a high-voltage capacitor module, an optical diode module, and a timing and triggering module, and configured to cause a power pulse to be transmitted to at least one detonator of at least one of the plurality of explosive units for detonation of the explosive material;
wherein the explosive units are configured to be positioned within the wellbore with the one or more detonation control modules positioned adjacent to the plurality of explosive units in the wellbore; and
wherein the one or more detonation control modules are configured to be remotely controlled from a location outside of the wellbore in order to detonate the plurality of explosive units within the wellbore in a predetermined manner.

2. The system of claim 1 , further comprising one or more propellant units positioned adjacent to the plurality of explosive units and one or more detonation control modules.

3. The system of claim 1 , further comprising a plurality of connectors, at least one of the connectors coupling two of the explosive units together in an end-to-end orientation and housing one of the detonation control modules.

4. The system of claim 3 , wherein the explosive units, propellant units, and connectors are coupled together end-to-end in an elongated string that is configured to be inserted into the wellbore.

5. The system of claim 4 , wherein the explosive units are positioned along the string in positions based on geological characteristics of a specific wellbore and a geologic formation adjacent to the wellbore.

6. The system of claim 4 , further comprising a tractor coupled to a distal end of the string and configured to pull the string into the wellbore.

7. The system of claim 4 , wherein the string is configured to curve with a radius of curvature of less than 500 feet.

8. The system of claim 3 , wherein the explosive units are arranged in explosive subunits of two explosive units with one of the connectors and one of the detonation control modules coupling the two explosive units together.

9. The system of claim 8 , wherein at least two of the explosive subunits are separated by propellant units.

10. The system of claim 1 , wherein all of the explosive units and detonation control modules are electrically coupled to each other and to a remote controller such that the explosive units can be detonated in a predetermined timing sequence within the wellbore.

11. The system of claim 1 , wherein the explosive material is configured to release a total energy of at least twelve kJ/cc upon detonation.

12. The system of claim 1 , wherein the explosive units are configured to be positioned within the wellbore in spaced apart positions relative to one another.

13. The system of claim 1 , wherein the predetermined manner comprises a predetermined timing sequence.

Assignees

• Los Alamos Nat Security Llc
• Triad Nat Security Llc

Inventors

• Mace Jonathan L
• Tappan Bryce C
• Seitz Gerald J
• Bronisz Lawrence E

Classifications

• F42D3/00

  Particular applications of blasting techniques {(explosive welding B23K20/08; explosive bolts or actuators F42B3/006; explosive valves F16K13/06; cutting devices actuated by explosion B23D15/145; pyrotechnical actuators F15B15/19; switching devices actuated by explosion H01H39/00)} · CPC title

• F42C15/42

  from a remote location, e.g. for controlled mines or mine fields · CPC title

• F42D3/06

  for seismic purposes · CPC title

• Y10T29/49826

  Assembling or joining · CPC title

• F42D1/055

  specially adapted for firing multiple charges with a time delay · CPC title