U.S. patent number 10,385,668 [Application Number 15/373,070] was granted by the patent office on 2019-08-20 for downhole wellbore high power laser heating and fracturing stimulation and methods.
This patent grant is currently assigned to SAUDI ARABIAN OIL COMPANY. The grantee listed for this patent is Saudi Arabian Oil Company. Invention is credited to Sameeh Issa Batarseh.
![](/patent/grant/10385668/US10385668-20190820-D00000.png)
![](/patent/grant/10385668/US10385668-20190820-D00001.png)
![](/patent/grant/10385668/US10385668-20190820-D00002.png)
![](/patent/grant/10385668/US10385668-20190820-D00003.png)
![](/patent/grant/10385668/US10385668-20190820-D00004.png)
United States Patent |
10,385,668 |
Batarseh |
August 20, 2019 |
Downhole wellbore high power laser heating and fracturing
stimulation and methods
Abstract
A system for fracturing a formation comprising a laser surface
unit configured to generate a laser beam, a power cable
electrically connected to a power source, a fluid line connected to
a cooling fluid source, a protective shaft extending into the
wellbore, the motor configured to rotate a motor shaft, and the
thermal shocking tool comprising a protective case, a rotational
shaft connected to the motor shaft, the laser delivery device
extending from the rotational shaft configured to transform the
laser beam to a focused laser beam operable to increase the
temperature of the formation to a fracture temperature, and the
cooling system extending from the rotational shaft opposite the
laser delivery device configured to introduce the cooling fluid
stream onto the formation such that the cooling fluid stream
reduces the temperature of the formation such that thermal shocks
occur and fractures are formed in the formation.
Inventors: |
Batarseh; Sameeh Issa (Dhahran
Hills, SA) |
Applicant: |
Name |
City |
State |
Country |
Type |
Saudi Arabian Oil Company |
Dhahran |
N/A |
SA |
|
|
Assignee: |
SAUDI ARABIAN OIL COMPANY
(SA)
|
Family
ID: |
60888627 |
Appl.
No.: |
15/373,070 |
Filed: |
December 8, 2016 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20180163524 A1 |
Jun 14, 2018 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B
36/001 (20130101); E21B 36/04 (20130101); E21B
47/00 (20130101); E21B 43/2405 (20130101); E21B
43/26 (20130101); E21B 43/114 (20130101); E21B
43/11 (20130101) |
Current International
Class: |
E21B
43/24 (20060101); E21B 47/00 (20120101); E21B
36/04 (20060101); E21B 36/00 (20060101); E21B
43/114 (20060101); E21B 43/11 (20060101); E21B
43/26 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
2420135 |
|
May 2006 |
|
GB |
|
20040009958 |
|
Jan 2004 |
|
WO |
|
2016090229 |
|
Jun 2016 |
|
WO |
|
2016186690 |
|
Nov 2016 |
|
WO |
|
Other References
PCT/US2014/036553 International Search Report and Written Opionion
dated Feb. 18, 2015; 11 pgs. cited by applicant .
PCT/US2017/065003 International Search Report and Written Opionion
dated Apr. 5, 2018; 15 pgs. cited by applicant .
Batarseh et al."Well Perforation Using High-Power Lasers" SPE
Annual Technical Conference and Exhibition, SPE 84418, Denver,
Colorado, Oct. 5-8, 2003, 10 pages. cited by applicant .
Anonymous"Laser Applications Laboratory--Laser Oil & Gas Well
Drilling" Argonne National Laboratory, Nuclear Engineering
Division, http://www.ne.anl.gov/facilities/lal/laser_drilling.html,
printed Feb. 5, 2013, 2 pages. cited by applicant .
Bakhtbidar et al."Application of Laser Technology for Oil and Gas
Wells Perforation" SPE/IADC Middle East Drilling Technology
Conference and Exhibition, SPE/IADC 148570, Muscat, Oman, Oct.
24-26, 2011, 12 pages. cited by applicant .
Batarseh et al."Deep hole penetration of rock for oil production
using Ytterbium fiber laser" SPIE Proceedings, Conference vol.
5448, High-Power Laser Ablation V, 818, Taos, New Mexico, Sep. 20,
2004, 9 pages. cited by applicant .
Batarseh et al."Innovation in Wellbore Perforation Using High-Power
Laser" International Petroleum Technology Conference, IPTC 10981,
Doha, Qatar, Nov. 21-23, 2005, 7 pages. cited by applicant .
Yaseen, et al. "The Geo-Materials Fracture by Thermal Process",
Proceedings, Thirty-Ninth Workshop on Geothermal Reservoir
Engineering Stanford University, Stanford, California, Feb. 24-26,
2014, SGP-TR-202, XP 55460344A, pp. 1-7. cited by
applicant.
|
Primary Examiner: Gray; George S
Attorney, Agent or Firm: Bracewell LLP Rhebergen; Constance
G.
Claims
What is claimed is:
1. A system for fracturing a formation from a wellbore extending
into the formation from a surface, the system comprising: a laser
surface unit, the laser surface unit located on the surface, the
laser surface unit configured to generate a laser beam; a fiber
optic cable, the fiber optic cable optically connected to a laser
delivery device of a thermal shocking tool, the fiber optic cable
configured to transmit the laser beam to the laser delivery device
to produce a focused laser beam; a power cable, the power cable
electrically connected to a power source on the surface, the power
cable configured to transmit electrical energy to a motor; a fluid
line, the fluid line connected to a cooling fluid source on the
surface, the fluid line configured to supply a cooling fluid to a
cooling system of the thermal shocking tool to produce a cooling
fluid stream; a protective shaft, the protective shaft extending
into the wellbore, wherein the fiber optic cable, the power cable,
and the fluid line are contained within the protective shaft; the
motor, the motor configured to rotate a motor shaft; a purge
nozzle, the purge nozzle positioned between the surface and the
motor, where the purge nozzle is configured to keep debris from
settling on the motor; and the thermal shocking tool physically
connected to the motor, the thermal shocking tool comprising: a
protective case, the protective case configured to encompass the
laser delivery device and the cooling system, a rotational shaft,
the rotational shaft connected to the motor shaft such that as the
motor shaft rotates the rotational shaft rotates, the laser
delivery device extending from the rotational shaft, the laser
delivery device configured to transform the laser beam to a focused
laser beam, wherein the focused laser beam is operable to increase
the temperature of the formation to a fracture temperature, and the
cooling system, the cooling system extending from the rotational
shaft opposite the laser delivery device, the cooling system
comprising one or more cooling nozzles extending through the
protective case such that the one or more cooling nozzles are
configured to introduce the cooling fluid stream onto the formation
such that the cooling fluid stream reduces the temperature of the
formation, wherein the laser delivery device and the cooling system
rotate around the wellbore as the rotational shaft rotates, wherein
rotation of the rotational shaft is configured to alternate between
increasing the temperature of the formation and reducing the
temperature of the formation such that thermal shocks occur and
fractures are formed in the formation.
2. The system of claim 1, wherein the cooling fluid is selected
from the group consisting of nitrogen gas, liquid nitrogen, helium,
air, carbon dioxide, and water.
3. The system of claim 1, wherein the fracture temperature is 2000
deg. C.
4. The system of claim 1 further comprising an acoustic capability,
wherein the acoustic capability is configured to monitor and record
a fracturing sound due to the thermal shocking tool, wherein the
acoustic capability is selected from the group consisting of
transducers, geophones, and combinations of the same.
5. The system of claim 1, wherein the laser delivery device is
positioned to introduce the focused laser beam to the formation at
a pre-determined angle.
6. A method for fracturing a formation from a wellbore extending
into the formation from a surface, the method comprising the steps
of: introducing a focused laser beam to the formation such that the
focused laser beam is operable to increase the temperature of the
formation to a fracture temperature, wherein the focused laser beam
is produced by a laser delivery device, the laser delivery device
extending from a rotational shaft; introducing a cooling fluid
stream to the formation such that the cooling fluid stream is
operable to reduce the temperature of the formation, wherein the
cooling fluid stream is produced by a cooling system, the cooling
system device extending from the rotational shaft opposite from the
laser delivery device; rotating the rotational shaft such that the
formation is alternately introduced to the focused laser beam and
the cooling fluid such that thermal shocks occur and fractures in
the formation are formed; transmitting electrical energy from a
power source to a motor through a power cable; transforming the
electrical energy to mechanical energy in the motor, such that the
mechanical energy rotates a motor shaft, wherein the motor shaft is
connected to the rotational shaft such that as the motor shaft
rotates the rotational shaft rotates; and introducing a fluid
through a purge nozzle positioned between the surface and the
motor, where the purge nozzle is configured to keep debris from
settling on the motor.
7. The method of claim 6, further comprising the steps of:
generating a laser beam in a laser surface unit; and transmitting
the laser beam from the laser surface unit to the laser delivery
device through a fiber optic cable.
8. The method of claim 6, wherein the cooling fluid is selected
from the group consisting of nitrogen gas, liquid nitrogen, helium,
air, carbon dioxide, and water.
9. The method of claim 6, wherein the fracture temperature is 2000
deg. C.
10. The method of claim 6 further comprising the step of measuring
by an acoustic capability fracturing sound due to the thermal
shocking tools, wherein the acoustic capability is selected from
the group consisting of transducers, geophones, and combinations of
the same.
11. The method of claim 6, wherein the laser delivery device is
positioned to introduce the focused laser beam to the formation at
a pre-determined angle.
Description
TECHNICAL FIELD
Disclosed are apparatus and methods for wellbore stimulation. More
specifically, embodiments related to apparatus and methods that
incorporate lasers for wellbore stimulation applications.
BACKGROUND
Methods for stimulating a wellbore aim to provide a pathway for
fluids to flow from the formation to the wellbore. Hydraulic
fracturing is one method for stimulating a wellbore. Conventional
hydraulic fracturing injects water at high pressure into the
wellbore, which causes fractures of the formation. In conventional
hydraulic fracturing, an explosive charge is used to perforate the
casing and cementing. An explosive charge is a high impact
technology that can cause compaction, deformation of the hole, and
sanding and crushing the grains of the rock material. The crushed
grains of rock material can be pushed into the formation, blocking
the formation and reducing production.
Additionally, the use of water in conventional hydraulic fracturing
is incompatible with certain types of formation, such as shale.
Water in shale can cause clay swelling, which blocks flow from the
formation to the wellbore.
SUMMARY
Disclosed are apparatus and methods for wellbore stimulation. More
specifically, embodiments related to apparatus and methods that
incorporate lasers for wellbore stimulation applications.
In a first aspect, a system for fracturing a formation from a
wellbore extending into the formation from a surface is provided.
The system includes a laser surface unit located on the surface,
the laser surface unit configured to generate a laser beam, a fiber
optic cable optically connected to a laser delivery device of a
thermal shocking tool, the fiber optic cable configured to transmit
the laser beam to the laser delivery device to produce a focused
laser beam, a power cable electrically connected to a power source
on the surface, the power cable configured to transmit electrical
energy to a motor, a fluid line connected to a cooling fluid source
on the surface, the fluid line configured to supply a cooling fluid
to a cooling system of the thermal shocking tool to produce a
cooling fluid stream, a protective shaft extending into the
wellbore, wherein the fiber optic cable, the power cable, and the
fluid line are contained within the protective shaft, the motor
configured to rotate a motor shaft, and the thermal shocking tool
physically connected to the motor. The thermal shocking tool
includes a protective case configured to encompass the laser
delivery device and the cooling system, a rotational shaft
connected to the motor shaft such that as the motor shaft rotates
the rotational shaft rotates, the laser delivery device extending
from the rotational shaft, the laser delivery device configured to
transform the laser beam to a focused laser beam, wherein the
focused laser beam is operable to increase the temperature of the
formation to a fracture temperature, and the cooling system
extending from the rotational shaft opposite the laser delivery
device, the cooling system comprising one or more cooling nozzles
extending through the protective case such that the one or more
cooling nozzles are configured to introduce the cooling fluid
stream onto the formation such that the cooling fluid stream
reduces the temperature of the formation, where the laser delivery
device and the cooling system rotate around the wellbore as the
rotational shaft rotates, where rotation of the rotational shaft is
configured to alternate between increasing the temperature of the
formation and reducing the temperature of the formation such that
thermal shocks occur and fractures are formed in the formation.
In certain aspects, the system further includes a purge nozzle, the
purge nozzle positioned between the surface and the motor, where
the purge nozzle is configured to keep debris from settling on the
motor. In certain aspects, the cooling fluid is selected from the
group consisting of nitrogen gas, liquid nitrogen, helium, air,
carbon dioxide, and water. In certain aspects, the fracture
temperature is 2000 deg. C. In certain aspects, the system further
includes an acoustic capability. In certain aspects, the focused
laser beam can increase the temperature of the formation to the
fracture temperature in less than 1 second. In certain aspects, the
laser delivery device can be positioned to introduce the focused
laser beam to the formation at a pre-determined angle.
In a second aspect, a method for fracturing a formation from a
wellbore extending into the formation from a surface is provided.
The method includes the steps of introducing a focused laser beam
to the formation such that the focused laser beam is operable to
increase the temperature of the formation to a fracture
temperature. The focused laser beam is produced by a laser delivery
device extending from a rotational shaft. The method further
includes a step of introducing a cooling fluid stream to the
formation such that the cooling fluid stream is operable to reduce
the temperature of the formation, where the cooling fluid stream is
produced by a cooling system. The cooling system device extending
from the rotational shaft opposite from the laser delivery device;
and rotating the rotational shaft such that the formation is
alternately introduced to the focused laser beam and the cooling
fluid such that thermal shocks occur and fractures in the formation
are formed.
In certain aspects, the method further includes the steps of
generating a laser beam in a laser surface unit, and transmitting
the laser beam from the laser surface unit to the laser delivery
device through a fiber optic cable. In certain aspects, the method
further includes the steps of transmitting electrical energy from a
power source to a motor through a power cable, and transforming the
electrical energy to mechanical energy in the motor, such that the
mechanical energy rotates a motor shaft, wherein the motor shaft is
connected to the rotational shaft such that as the motor shaft
rotates the rotational shaft rotates. In certain aspects, the
method further includes the step of measuring the sound emitted by
an acoustic capability.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects, and advantages will become
better understood with regard to the following descriptions,
claims, and accompanying drawings. It is to be noted, however, that
the drawings illustrate only several embodiments and are therefore
not to be considered limiting of the inventive scope as it can
admit to other equally effective embodiments.
FIG. 1 is a plan view of an embodiment of the laser fracturing
tool.
FIG. 2 is a plan view of the laser fracturing tool including the
motor and the thermal shocking tool.
FIG. 3 is a plan view of an embodiment of the thermal shocking
tool.
FIG. 4 is a pictorial representation of core samples fractured by
laser.
DETAILED DESCRIPTION
While the scope will be described with several embodiments, it is
understood that one of ordinary skill in the relevant art will
appreciate that many examples, variations and alterations to the
apparatus and methods described are within the scope and spirit of
the embodiments. Accordingly, the embodiments described here are
set forth without any loss of generality, and without imposing
limitations. Those of skill in the art understand that the
inventive scope includes all possible combinations and uses of
particular features described in the specification. In both the
drawings and the detailed description, like numbers refer to like
elements throughout.
Described are an apparatus and methods for fracturing a formation
with a laser fracturing tool. The laser fracturing tool can be used
to establish fluid communication between the wellbore and the
formation to improve production of formation fluids.
Advantageously, the laser fracturing tool can provide a targeted
method of fracturing the formation as compared to a conventional
hydraulic fracturing. The laser fracturing tool can be used to
target the location of the fracture, such as targeting the angle
and depth of the fracture. In addition, the laser can be located
along fault lines. Advantageously, the rotation of the laser
fracturing tool means the method of fracturing can be implemented
around the entire circumference of the wellbore without the need to
reposition the tool. Advantageously, the laser fracturing tool in
the absence of a hydraulic fracturing step. The absence of
hydraulic fracturing has environmental advantages as hydraulic
fracturing consumes and pollutes large quantities of water. The
laser fracturing tool produces less damage to the rock material of
a formation than conventional hydraulic fracturing.
FIG. 1 is an elevation view of laser fracturing tool 100. Laser
fracturing tool 100 is deployed in wellbore 10 of formation 40.
Surface 30 is the surface of the earth from which wellbore 10
extends. Wellbore 10 extends from surface 30 into formation 40.
Formation 40 can be any type of formation composed of any type of
rock material. In at least one embodiment, formation 40 contains
limestone. In at least one embodiment, formation 40 contains
sandstone. In at least one embodiment, formation 40 contains shale.
Wellbore 10 can be finished with casing 20 and cement 25 for
reinforcement.
Laser surface unit 50 can be located on surface 30 near wellbore
10. Laser surface unit 50 can be in optical communication with
laser fracturing tool 100 via fiber optic cable 55. Laser surface
unit 50 can be configured to excite energy to a level above the
sublimation point of formation 40 to form a laser beam (not shown).
The sublimation point of formation 40 can be determined based on
the rock material contained in formation 40, where the rock
material controls the sublimation point which then controls the
excitation energy of the laser beam. In at least one embodiment,
laser surface unit 50 can be tuned to excite energy to different
excitation levels as can be required for different formations.
Laser surface unit 50 can by any type of laser unit capable of
generating a laser beam and introducing said laser beam into a
fiber optic cable. Examples of laser surface unit 50 include lasers
of ytterbium, erbium, neodymium, dysprosium, praseodymium, and
thulium ions. In at least one embodiment, laser surface unit 50 can
be a 5.34-kW ytterbium doped multiclad fiber laser.
Fiber optic cable 55 can be any cable containing an optical fiber
capable of transmitting a laser beam from laser surface unit 50 to
laser fracturing tool 100. Fiber optic cable 55 can include one or
more optical fibers. In an alternate embodiment, one or more fiber
optic cables can provide electrical communication between laser
surface unit 50 and laser fracturing tool 100. In at least one
embodiment, fiber optic cable 55 provides a path for light from
laser surface unit 50 to laser fracturing tool 100. In at least one
embodiment, fiber optic cable 55 can conduct a raw laser beam from
laser surface unit 50 to laser fracturing tool 100. A "raw laser
beam" as used herein refers to a laser beam that has not been
passed through lenses or otherwise focused.
Power source 60 can be located on surface 30 near wellbore 10.
Power source 60 can be in electrical communication with laser
fracturing tool 100 via power cable 65. Power source 60 can be any
apparatus capable of generating electrical energy. Power cable 65
can be any type of cable capable of transmitting electrical energy
to laser fracturing tool 100.
Cooling fluid source 70 can be located on surface 30 near wellbore
10 and can provide a cooling fluid to laser fracturing tool 100.
Cooling fluid source 70 is in fluid communication with laser
fracturing tool 100 via fluid line 75, such that the cooling fluid
is delivered to laser fracturing tool 100 from cooling fluid source
70. Fluid line 75 can be any type of tube capable of supplying a
fluid to laser fracturing tool 100. The cooling fluid can include
nitrogen gas, liquid nitrogen, helium, air, carbon dioxide, and
water. The cooling fluid can be selected based on the rock material
of formation 40 and the thermal properties of the rock material.
The temperature gradient desired between the fracture temperature
and the cooled temperature, the rotation period of the thermal
shocking tool, and the efficiency of the cooling fluid in reducing
the temperature of the rock material. In at least one embodiment,
one or more fluid lines 75 can be in fluid communication with
cooling fluid source 70 and laser fracturing tool 100.
Fiber optic cable 55, power cable 65, and fluid line 75 can be
encompassed in protective shaft 80. Protective shaft 80 can be any
material of construction suitable for use in a downhole environment
without experiencing mechanical or chemical failure. As used here,
"downhole environment" refers to the high operating pressure, high
operating temperature, and fluid conditions that can be found in a
wellbore extending into a formation.
FIG. 2 is a section view in elevation of one embodiment of laser
fracturing tool 100 as understood with reference to FIG. 1. Laser
fracturing tool 100 includes motor 200 and thermal shocking tool
300. Power cable 65 is in electrical communication with motor 200,
such that power cable 65 transmits electrical energy to motor 200.
Motor 200 is physically connected to motor shaft 210. Motor 200 can
be any motor capable of converting electrical energy transmitted by
power cable 65 into mechanical energy to rotate motor shaft 210 in
a downhole environment. Motor shaft 210 is physically connected to
rotational shaft 310 of thermal shocking tool 300.
Fiber optic cable 55 is in optical communication with thermal
shocking tool 300. Cooling fluid line 75 is in fluid communication
with thermal shocking tool 300.
In at least one embodiment, purge nozzle 220 can be located between
motor 200 and surface 30, such that purge nozzle 220 is configured
to deliver a fluid to the wellbore. In at least one embodiment,
purge nozzle 220 can be located between motor 200 and surface 30
near motor 200 such that purge nozzle 220 is operable to deliver
the fluid near motor 200. In at least one embodiment, purge nozzle
220 delivers the fluid such that the fluid is operable to clean
motor 200, such that the purge fluid from purge nozzle 220 can keep
dust and debris from settling on motor 200. In at least one
embodiment, purge nozzle 220 delivers the fluid such that the fluid
is operable to direct the produced fluid in wellbore 10. As used
here, "produced fluid" refers to the fluid that flows from the
formation into the wellbore due to fracturing of the formation by
laser fracturing tool 100. In at least one embodiment, one or more
purge nozzles 220 can be configured in a purge nozzle configuration
(not shown) such that the purge nozzle configuration is configured
to deliver the fluid to multiple points in wellbore 10. The purge
fluid can be any fluid capable of cleaning the motor and directing
fluid. Examples of purge fluid can include air and nitrogen gas.
The purge fluid can be at the ambient temperature of the purge
fluid source (not shown). In an alternate embodiment, the purge
fluid is from cooling fluid source 70.
FIG. 3 is a section view in elevation of a thermal shocking tool
300 with reference to features described in FIG. 2. Thermal
shocking tool 300 includes protective case 305, rotational shaft
310, cooling system 320, and laser delivery device 330.
Protective case 305 surrounds rotational shaft 310, cooling system
320, and laser delivery device 330. Protective case 305 can be
formed from any materials capable of withstanding the downhole
environment without suffering mechanical failure. Cooling system
320 and laser delivery device 330 can extend into and through
protective case 305.
Rotational shaft 310 connected to motor shaft 210 extends through
protective case 305. Rotational shaft 310 rotates as motor shaft
210 rotates as driven by motor 200. Rotational shaft 310 provides
an axis around which cooling system 320 and laser delivery device
330 rotate. Rotational shaft 310 can provide physical support, such
as an anchor to cooling system 320 and laser delivery device 330.
Cooling system 320 and laser delivery device 330 are mounted to
rational shaft 310 such that cooling system 320 is opposite laser
delivery device 330. As used herein, "opposite" refers to a
position 180 degrees around the axis formed by rotational shaft
310, such that if cooling system 320 extends perpendicularly from
rotational shaft 310 at zero (0) degrees, laser delivery device
extends perpendicularly from rotational shaft 310 at one-hundred
eighty (180) degrees. Rotational shaft 310 can be any material of
construction suitable for use in a downhole environment that is
rigid enough to provide physical support to cooling system 320 and
laser delivery device 330.
Cooling system 320 can include one or more cooling nozzles 325 as
shown in FIG. 3. Cooling nozzles 325 are fluidly connected to fluid
line 75, such that the cooled purge fluid is delivered from cooling
fluid source 70. Cooling system 320 can be configured to introduce
the cooling fluid to formation 40 as a cooling fluid stream. The
cooling fluid stream is operable to reduce the temperature
formation 40.
Laser delivery device 330 is optically connected to fiber optic
cable 55. Laser delivery device 330 can be configured to focus the
laser beam from fiber optic cable 55 to produce a focused beam. In
one embodiment, laser delivery device 330 can incorporate the
features and details set forth in U.S. Pat. No. 9,217,291.
The focused laser beam is operable to increase the temperature of
formation 40. The focused laser beam can be directed to sublimate
the casing and the cement prior to contact formation 40.
Advantageously, the focused laser beam can precisely cut the casing
and the cement. The focused laser beam can increase the temperature
of formation 40 in less than one second to a fracture temperature.
The fracture temperature can reach 2,000 degrees Celsius (deg C.).
The less than one second increase in temperature to the fracture
temperature can cause thermal shocks in formation 40 which results
in fractures, microfractures and cracks in the rock material of
formation 40. As used here, "microfractures" refers to fractures in
the range from a millimeter to a few centimeters that can be used
for initiating fractures. As used here, "thermal shocks" refers to
the expansion and contraction of the formation rock over a time
period on the order of seconds. As thermal shocking tool 300
rotates, laser delivery device 330 continuously causes an increase
in temperature of formation 40 around the wellbore. While laser
delivery device 330 increases the temperature of formation 40,
cooling system 320 decreases the temperature. The cooling fluid
stream can be directed at formation 40, such that the cooling fluid
stream can reduce the temperature of the formation to a cooled
temperature. The cooled temperature depends on the fluid used as
the cooling fluid stream.
The laser delivery device can include acoustic capability to
monitor and record the fracturing sound due to the thermal shocking
tool. Acoustic capability can include transducers or geophones.
Fracturing sound can be used to indicate the fracture length and
size. The acoustic capability can be placed above the motor, below
the thermal shocking tool, or both above the motor and below the
thermal shocking tool. Power can be supplied to the acoustic
capability from power source 60 (not shown). The acoustic
capability can transmit the measurements directly to the surface or
can be stored and retrieved after the laser fracturing.
EXAMPLE
Example 1
A dry core sample measuring 2''.times.2'' of Berea and limestone
was obtained. A 3 kW power laser was used to produce a continuous
laser beam of 0.35 inches. The laser beam was turned on for four
(4) seconds before being switched off. Fractures immediately formed
in the core sample. Air, at room temperature, was used as the
cooling fluid stream on one side of the core sample to orient the
fractures. As can be seen in FIG. 4, fractures formed in the core
sample.
Although the technology has been described in detail, it should be
understood that various changes, substitutions, and alterations can
be made hereupon without departing from the inventive principle and
scope. Accordingly, the scope of the embodiments should be
determined by the following claims and their appropriate legal
equivalents.
The singular forms "a," "an," and "the" include plural referents,
unless the context clearly dictates otherwise.
Optional or optionally means that the subsequently described event
or circumstances can or may not occur. The description includes
instances where the event or circumstance occurs and instances
where it does not occur.
Ranges may be expressed as from one particular value to another
particular value. When such a range is expressed, it is to be
understood that another embodiment is from the one particular value
to the other particular value, along with all combinations within
said range.
Throughout this application, where patents or publications are
referenced, the disclosures of these references in their entireties
are intended to be incorporated by reference into this application,
in order to more fully describe the state of the art, except when
these references contradict the statements made here.
As used here and in the appended claims, the words "comprise,"
"has," and "include" and all grammatical variations thereof are
each intended to have an open, non-limiting meaning that does not
exclude additional elements or steps.
* * * * *
References