DE112013007387T5 - Encapsulated explosives for drilling wells - Google Patents

Abstract

Systems and methods for drilling operations may use encapsulated explosives to supplement the performance of the well tools. An exemplary method may include: drilling a wellbore penetrating a subterranean formation with a downhole cutting tool; Circulating a drilling fluid in the wellbore, the drilling fluid comprising a base fluid and an encapsulated explosive having an average diameter of from about 10 nm to about 20 micrometers; Triggering the detonation of the encapsulated explosive; and detonating the encapsulated explosive near a portion of the subterranean formation adjacent the well tool.

Description

GENERAL PRIOR ART

The embodiments described herein relate to systems and methods for drilling operations that use encapsulated explosives to supplement the performance of the well tools.

Borehole cutting tools are commonly used in the oil and gas industry to drill wells into subterranean formations. A typical drilling operation associated with downhole cutting tools includes cutting elements that penetrate or break adjacent formation materials and remove the formation materials by a scraping action. Drilling fluid that is circulated during drilling may also be provided to perform a number of functions, including washing away formation materials and other debris from the bottom of a well, cleaning associated cutting structures, and moving formation wells radially outward and then up to an associated wellbore surface.

The degree of penetration of the well tool is a measure of drilling efficiency. With increased degree of penetration, the grinding wear of the borehole cutting tool increases. The wear of the downhole cutting tool requires regular replacement of the downhole cutting tool. The replacement includes stopping the drilling operation, retrieving the worn downhole cutting tool to the surface, and then lowering a new or refurbished downhole cutting tool back into the wellbore. Replacing a downhole cutting tool can thus be a rather costly and time consuming process.

BRIEF DESCRIPTION OF THE DRAWINGS

The following figures are intended to illustrate certain aspects of the embodiments described herein and are not to be considered as exclusive embodiments. The disclosed subject matter may be subject to significant modifications, alterations and equivalents in form and function that would be obvious to those skilled in the art having the benefit of this disclosure.

1 illustrates a system that is suitable for drilling a wellbore that penetrates into a subterranean formation.

2A and 2 B 1 and 2 respectively illustrate a drill bit in plan view and a cross-sectional view, respectively, including an ultrasonic device for triggering the encapsulated explosives described herein, according to at least one embodiment described herein.

3 FIG. 5 illustrates a scavenger incorporating equipment for triggering the encapsulated explosives described herein according to at least one embodiment described herein.

4 Figure 5 illustrates a drill bit and a portion of a drill string with a container of the encapsulated explosives described herein.

DETAILED DESCRIPTION

The embodiments described herein relate to systems and methods for drilling operations that use encapsulated explosives to supplement the performance of the well tools.

In one aspect, the disclosed systems and methods relate to drilling operations that involve various particular applications of encapsulated explosives that may be triggered to detonate near a portion of a subterranean formation at or near a well tool. The detonation weakens and / or breaks the adjacent subterranean formation, which can complement the action of the well tool. Thus, in turn, an increased degree of penetration can be achieved with less torque and power consumption and less well tool wear. As a result, well operators can benefit from reduced cost and time in the drilling operations.

As used herein, the term "well tool" refers to downhole tools that can drill at least a portion of a wellbore that penetrates into a subterranean formation. Examples of wellhead cutting tools include, but are not limited to, compact polycrystalline diamond compact (PDC) drill bits, scrapers, impregnated bits, roller bits, scrapers with cutters, and the like.

1 FIG. 3 illustrates an example system that may implement the principles of the present disclosure, according to one or more embodiments. As shown, uses a rig 100 Sections of pipe 102 (sometimes referred to as a drill string) to apply torque to a downhole cutting tool 104 to transfer, and a pump 106 can be used to apply drilling fluid (as represented by arrows A) through the sections of the pipe 102 to circulate to the bottom of the borehole. If that is Drill hole cutting tool rotates, forces the load applied to the drill bit (weight-on-bit, "WOB") various cutting elements of the cutting tool 104 into the drilled formation. In this way, the cutting elements exert a compressive load that exceeds the yield strength of the formation and thereby dig through the formation. The resulting fragments (also referred to as "cuttings") are flushed away from the cutting surface by a heavy stream of drilling fluid (also referred to as "mud"). According to embodiments described herein, encapsulated explosives may be included in the drilling fluid and triggered to detonate adjacent a portion of the formation that is from the well tool 104 is penetrated. The detonation of the encapsulated explosives in the wellbore can reduce the yield strength of the formation adjacent to the well tool 104 lowering, thus enabling a more efficient drilling operation and the life of the cutting tool 104 increase.

As used herein, the term "encapsulated explosive" refers to an explosive composition essentially comprised of another composition. Examples of encapsulated explosives may include, but are not limited to, explosive compositions essentially comprised of a micelle, a liposome, a cross-linked liposome, a polymer bubble, a dendritic polymer, a polymer coating, a mesoporous metal oxide particle, and any hybrid thereof. Other examples of encapsulated explosives may include, but are not limited to, coated nanoparticles, coated microparticles, impregnated mesoporous metal oxide nanoparticles, impregnated mesoporous metal oxide microparticles, and the like. Drilling fluids described herein may in some embodiments include combinations of any of the aforementioned encapsulated explosives.

Examples of explosive compositions may include, but are not limited to, thermite, octogen, pentaerythritol tetranitrate, tetranitrotoluene, an explosive nitroamine, lead picrate, mercury fulminate, iodine nitride, potassium perchlorate, ammonium perchlorate, and the like, and a combination thereof. In some cases, the explosive composition may be a binary explosive wherein the individual components of the binary explosive are individually encapsulated explosives (i.e., those comprising a plurality of first encapsulated components and a plurality of second encapsulated components). Examples of binary explosive compositions may include, but are not limited to, ammonium nitrate / heavy oil, ammonium nitrate / nitromethane, ammonium nitrate / aluminum, and nitroethane / physical sensitizer.

In some embodiments, the encapsulated explosives described herein may have an average diameter ranging from a lower limit of about 10 nm, 50 nm, 100 nm or 500 nm to an upper limit of about 20 microns, 10 microns, 5 microns, 1 microns or 500 nm, wherein the average diameter may be between any lower limit and any upper limit and includes any subgroup therebetween. As used herein, the term "average diameter" refers to the mean diameter value at the smallest dimension. For example, an encapsulated explosive, which is a coated nanorod having a length of about 50 nm and an aspect ratio of five, has a diameter of about 10 nm as used herein.

Blends of encapsulated explosives of different size and / or composition may be useful in adjusting the depth of the downhole explosion.

Suitable base fluids may include, but are not limited to, oil-based fluids, aqueous-based fluids, aqueous-miscible fluids, water-in-oil emulsions, or oil-in-water emulsions. One skilled in the art having the benefit of this disclosure will recognize that the base fluid should be selected to be compatible with at least the encapsulated explosive and the triggering methods described herein. Suitable oil-based fluids may include alkanes, olefins, aromatic organic compounds, cyclic alkanes, paraffins, diesel fluids, mineral oils, desulfurized hydrogenated kerosenes, and any combination thereof. Suitable aqueous-based fluids may be fresh water; Salt water (eg, water containing one or more salts dissolved therein); Brine (eg saturated salt water); Seawater; and any combination thereof. Suitable aqueous-miscible fluids may include, but are not limited to, alcohols (e.g., methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, isobutanol and tert-butanol), glycerols, glycols (e.g. Polyglycols, propylene glycol and ethylene glycol), polyglycolamines, polyols, any derivatives thereof, any in combination with salts (e.g., sodium chloride, calcium chloride, calcium bromide, zinc bromide, potassium carbonate, sodium formate, potassium formate, cesium formate, sodium acetate, potassium acetate, calcium acetate, Ammonium acetate, ammonium chloride, ammonium bromide, sodium nitrate, potassium nitrate, ammonium nitrate, ammonium sulfate, calcium nitrate, sodium carbonate and potassium carbonate), any in combination with an aqueous-based fluid and any combination thereof. Suitable water-in-oil emulsions, also known as invert emulsions, may have an oil-to-water ratio of a lower limit of greater than about 50:50, 55:45, 60:40, 65:35, 70:30 , 75:25 or 80:20 up to an upper limit of less than 100: 0, 95: 5, 90:10, 85:15, 80:20, 75:25, 70:30 or 65:35 by volume Base fluid, wherein the amount may be between any lower limit and any upper limit and includes any subgroup in between.

In some cases, the detonation of the encapsulated explosives can be triggered mechanically. For example, the encapsulated explosives may be crushed between the downhole cutting tool and the subterranean formation, and the physical act of crushing or grinding the encapsulated explosives serves to trigger their respective detonations. In another example, an ultrasound device (see 2 B ) disposed in the downhole cutting tool can be used such that cavitation generated by the ultrasonic device detonates the encapsulated explosives.

In some cases, the detonation of the encapsulated explosives can be thermally triggered. For example, the composition that encapsulates the explosive may be exposed to electromagnetic radiation at a frequency of about 10 ⁶ Hz to about 10 ¹⁷ Hz, causing the encapsulant composition to heat up and detonate the explosive. By way of non-limiting example, the encapsulated explosives containing functionalized fullerenes (eg, Dendrofullerene) or functionalized nanotubes for encapsulation may be heated (eg, by liposome, micelle, or polymer coating) by exposure to infrared or microwave radiation.

In another example involving both thermal and mechanical detonation, a mixture of first and second encapsulated explosives may be used, wherein the first encapsulated explosive is in a lower concentration, has higher detonation sensitivity, and has a higher explosive force than the second encapsulated explosive having. In these embodiments, the detonation of the first encapsulated explosive may be configured to detonate the second encapsulated explosive.

In some cases, the detonation of the encapsulated explosives can be chemically triggered. For example, the composition that encapsulates the individual components of a binary explosive may be compromised such that the two components can come into contact and detonate. The impairment of the composition that encapsulates the components can be achieved mechanically and / or thermally, as described herein with respect to detonation. In other instances, compromising the composition that encapsulates the components may be a chemical trigger by altering the pH and / or salinity of the drilling fluid. For example, liposomes and micelles containing ionic surfactants and / or polymers may be affected by changes in pH and salinity.

The triggering of the detonation of the encapsulated explosives may take place anywhere in a drilling system. Referring to 2A and 2 B For example, these each show a plan view and a cross-sectional view of an exemplary impregnated drill bit 200 , The drill bit 200 can be used to trigger the detonation by means of cavitation. The drill bit 200 has cutting surfaces 202 for clearing rock from the bottom of a borehole. Drilling fluid flows through the inner channel 204 ( 2 B ) of the drill string 206 and into a cavity 208 in the drill bit 200 is defined before it has different openings 210 in the head of the drill bit 200 are defined from the drill bit 200 exit. As in 2 B shown, can be an ultrasound device 212 in the cavity 208 of the drill bit 200 and can generate cavitation in the drilling fluid passing through the cavity 208 occurs. The position of the ultrasound device 212 in the cavity 208 , the composition of the encapsulated explosive and the flow rate of the drilling fluid may be adjusted to cause the encapsulated explosives to be released into the cavity 208 takes place, but their detonation takes place only when the encapsulated explosives from the openings 210 have leaked.

In some cases, the ultrasound machine can 212 be replaced by a laser or other device that generates electromagnetic radiation of a desired frequency. Accordingly, the drill bit 200 equally useful for thermal initiation of the encapsulated explosive. One skilled in the art having the benefit of this disclosure will recognize the variety of ways to use these tripping devices in the impregnated drill bit 200 or any other downhole cutting tool.

Referring to 3 This represents an exemplary scavenger 314 As shown, the scraper 314 a body 316 Include, attached to a shaft 318 is coupled. The body 316 can be one or more blocks 320 and or one or more feet 322 include, coupled to or otherwise formed thereon. In the illustrated embodiment 3 includes the evacuee 314 four blocks 320 and four feet 322 that are radial around the body 316 are arranged, for example, alternately. However, the scavenger can 314 alternatively any number of blocks 320 and feet 322 in any combination, as required for a particular application. The blocks 320 For example, they may be stabilizers or measuring blocks, or they may include cutting elements such as PDC bits. In some embodiments, the blocks 320 equipment 324 which may trigger the detonation of the encapsulated explosive (eg, ultrasound devices, lasers, or other devices that produce electromagnetic radiation of a desired frequency).

Every foot 322 can a head 326 include, the bearings, seals or other components for supporting cutting elements for clearing the borehole, such as a roller bit 328 , may include. The shaft 318 may be one or more fluid ports 330 and / or a borehole connector 332 for coupling the scraper 314 to other components in a drilling or excavating system, such as a pilot drill bit 334 or other drilling equipment. The connector 332 may include threads, holes, pins, profiles or similar components as required for a particular application. In the embodiment 3 is the pilot drill bit 334 as a hybrid drill bit, but it is understood that the pilot bit 334 may be any drill bit required for a particular application, such as a PDC drill bit, an impregnated drill bit, or a roller bit. In some cases, the pilot drill bit 334 Equipment that can trigger the encapsulated explosives, such as the equipment described above with reference to 2A and 2 B described (eg ultrasound machines, lasers etc.).

One of ordinary skill in the art having the benefit of this disclosure will recognize the variety of other equipment incorporation configurations that can initiate detonation. For example, the equipment between the scraper 314 and the pilot drill bit 334 be arranged and connected to the connector 332 out 3 be coupled. In another example, the equipment may be coupled to a stabilizer (not shown) connected to a drill bit 200 ( 2A and 2 B ), a pilot drill bit 334 , a scavenger 314 or a connector 332 or another similar downhole cutting tool or portion thereof.

In some cases, the encapsulated explosives may be in the drilling fluid as the drilling fluid is introduced into a wellbore. In other cases, the encapsulated explosives may be added to the drilling fluid at a location along the drill string. For example 4 a cross section of a portion of a drill string 406 which is attached to an impregnated drill bit 400 coupled, the drill string 406 configured to deliver the encapsulated explosives to the drilling fluid circulating thereby at one or more locations along the drill string 406 add. The drill string 406 can one or more containers 436 (Shown are two) upstream of the impregnated drill bit 400 are arranged, which may alternatively be any other well cutting tool. The containers 436 can use a variety of encapsulated explosives 438 contain and receive signals to the encapsulated explosives 438 via a communication line 440 or other suitable communication method (eg, acoustic telemetry, electromagnetic telemetry, radio waves, electronic signaling, etc.) into the drilling fluid. The container 436 may be configured to receive at least a portion of the encapsulated explosives upon receipt of a predetermined signal 438 into the drilling fluid released by the drill string 406 flows. The encapsulated explosives 438 can be triggered by any of the methods described herein.

In some cases, the drill string 406 that is attached to the impregnated drill bit 400 out 4 coupled, be useful for chemical release, the container 436 contains the chemical trigger (eg, acids, bases, salts and the like) or one of the two encapsulated components of a binary explosive composition. It will be understood that the use of the container (s) may beneficially mitigate the risk of premature explosion of the encapsulated explosives in the drill string upstream of the downhole cutting tool.

Referring again to 3 and continue with reference to 4 can parts of the equipment 324 who are at the evacuee 314 is arranged, through a container similar to the container 436 out 4 , Again, the use of the container 436 be advantageous to further reduce the risk of premature explosion.

In some embodiments, the detonation of the encapsulated explosives may be intermittent relative to the drilling operation. For example, the encapsulated explosives may be added intermittently to the drilling fluid (eg, prior to entering the wellbore or from a vessel) become. In another example, initiation of the detonation of the encapsulated explosives may be intermittent, with the encapsulated explosives present in the drilling fluid when no triggering is performed. In some cases, a hybrid of the two can be performed. The intermittent use and / or release of the encapsulated explosives may further reduce risks associated with their use.

In some embodiments, while drilling a borehole penetrating a subterranean formation, the encapsulated explosives may be implemented relative to selected rocks (e.g., contained in drilling fluid, or both) located in the subterranean formation, to complement the drilling through the rock. In some cases, the detection of the rock may be accomplished via one or more sensors located adjacent to a downhole cutting tool (eg, a bottomhole assembly, etc.), a drill string, or the like. In another example, torque, degree of penetration, well pressure, and other parameters used for drilling may indicate that a particular rock has been encountered in which the implementation of encapsulated explosives may be useful. In another example, seismic data and other formation data (e.g., core samples or the wellbore of a well in the same formation) may be used to identify the selected rock. In another example, a drilling / measuring / logging system may autonomously transmit or otherwise communicate signals to trigger (or.) The encapsulated explosive based on the subterranean formation information determined by the logging / measuring activity of the drilling system release the encapsulated explosives). In some embodiments, combinations of the above methods may be used to determine when the encapsulated explosives should be implemented.

• A: Ein Verfahren, das Folgendes beinhaltet: Bohren eines Bohrlochs, das eine unterirdische Formation durchdringt, mit einem Bohrlochschneidwerkzeug; Zirkulieren eines Bohrfluids in dem Bohrloch, wobei das Bohrfluid ein Basisfluid und einen verkapselten Sprengstoff mit einem mittleren Durchmesser von etwa 10 nm bis etwa 20 Mikrometern umfasst; Auslösen der Detonation des verkapselten Sprengstoffs; und Detonieren des verkapselten Sprengstoffs in der Nähe eines Abschnitts der unterirdischen Formation benachbart zu dem Bohrlochschneidwerkzeug;
• B: Ein Verfahren, das Folgendes beinhaltet: Bohren eines Bohrlochs, das eine unterirdische Formation durchdringt, mit einem Bohrlochschneidwerkzeug, das in Wirkbeziehung an einen Bohrstrang gekoppelt ist, und einen Behälter, der an wenigstens eins ausgewählt aus der Gruppe bestehend aus dem Bohrlochschneidwerkzeug und dem Bohrstrang gekoppelt ist, wobei der Behälter eine Vielzahl von verkapselten Sprengstoffe enthält; Zirkulieren eines Bohrfluids in dem Bohrloch; Freisetzen wenigstens eines Teils der verkapselten Sprengstoffe von dem Behälter und in das Bohrfluid, wobei die verkapselten Sprengstoffe einen mittleren Durchmesser von etwa 10 nm bis etwa 20 Mikrometern aufweisen; Auslösen der Detonation der verkapselten Sprengstoffe in dem Bohrfluid; und Detonieren der verkapselten Sprengstoffe in der Nähe eines Abschnitts der unterirdischen Formation benachbart zum Bohrlochschneidwerkzeug; und
• C: Ein Verfahren, das Folgendes beinhaltet: Bohren eines Bohrlochs, das eine unterirdische Formation durchdringt, mit einem Bohrlochschneidwerkzeug, das in Wirkbeziehung an einen Bohrstrang gekoppelt ist, und einen Behälter, der an wenigstens eins von dem Bohrlochschneidwerkzeug und dem Bohrstrang gekoppelt ist, wobei der Behälter eine Vielzahl von ersten verkapselten Komponenten enthält; Zirkulieren eines Bohrfluids in dem Bohrloch, wobei das Bohrfluid ein Basisfluid und eine Vielzahl von zweiten verkapselten Komponenten umfasst, wobei die erste und zweite Vielzahl von verkapselte Komponenten Teil eines binären Sprengstoffs bilden; Freisetzen wenigstens eines Teils der ersten verkapselte Komponenten aus dem Behälter in das Bohrfluid; Auslösen der Detonation des binären Sprengstoffs durch Vermischen der ersten verkapselten Komponenten mit den zweiten verkapselten Komponenten; und Detonieren des binären Sprengstoffs in der Nähe eines Abschnitts der unterirdischen Formation benachbart zu dem Bohrlochschneidwerkzeug.

Embodiments disclosed herein include:

• A: A method comprising: drilling a wellbore penetrating an underground formation with a downhole cutting tool; Circulating a drilling fluid in the wellbore, the drilling fluid comprising a base fluid and an encapsulated explosive having an average diameter of from about 10 nm to about 20 micrometers; Triggering the detonation of the encapsulated explosive; and detonating the encapsulated explosive near a portion of the subterranean formation adjacent the well tool;
• B: A method comprising: drilling a wellbore penetrating a subterranean formation with a wellbore cutting tool operably coupled to a drillstring; and a receptacle connected to at least one selected from the group consisting of the wellbore cutting tool and the wellbore Drill string is coupled, wherein the container contains a plurality of encapsulated explosives; Circulating a drilling fluid in the wellbore; Releasing at least a portion of the encapsulated explosives from the container and into the drilling fluid, the encapsulated explosives having an average diameter of from about 10 nm to about 20 microns; Triggering the detonation of the encapsulated explosives in the drilling fluid; and detonating the encapsulated explosives near a portion of the subterranean formation adjacent the well tool; and
• C: A method comprising: drilling a wellbore penetrating a subterranean formation with a wellbore cutting tool operably coupled to a drillstring and a receptacle coupled to at least one of the wellbore cutting tool and the drillstring; the container contains a plurality of first encapsulated components; Circulating a drilling fluid in the wellbore, the drilling fluid comprising a base fluid and a plurality of second encapsulated components, the first and second plurality of encapsulated components forming part of a binary explosive; Releasing at least a portion of the first encapsulated components from the container into the drilling fluid; Triggering the detonation of the binary explosive by mixing the first encapsulated components with the second encapsulated components; and detonating the binary explosive proximate a portion of the subterranean formation adjacent to the well tool.

Each of embodiments A, B and C may, unless otherwise indicated, comprise one or more of the following elements in any combination: Element 1: wherein triggering detonation of the encapsulated explosive exposing the encapsulated explosive to electromagnetic radiation at a frequency of about 10 ⁶ Hz to about 10 ¹⁷ Hz; Element 2: wherein triggering the detonation of the encapsulated explosive comprises crushing the encapsulated explosive between the well tool and the subterranean formation; Element 3: wherein initiating the detonation of the encapsulated explosive comprises introducing cavitation into the drilling fluid; Element 4: where the triggering of the detonation of the encapsulated explosive is the in-process Bringing the encapsulated explosive with a chemical trigger includes; Element 5: wherein the initiation of the detonation of the encapsulated explosive is intermittent; Element 6: initiation of the detonation of the encapsulated explosive occurs upstream of the drill bit in a drill string coupled to the well tool; Element 7: wherein the encapsulated explosive is at least one selected from the group consisting of a liposome, a crosslinked liposome, a nanoliposome, a polymer bubble, a dendritic polymer, a coated nanoparticle, a coated microparticle, an impregnated nanoparticle, an impregnated microparticle, and a any hybrid thereof; Item 8: wherein the encapsulated explosive comprises at least one selected from the group consisting of thermite, octogen, pentaerythritol tetranitrate, tetranitrotoluene, an explosive nitroamine, lead picrate, mercury fulminate, iodine nitride, potassium perchlorate, ammonium perchlorate, and the like and a combination thereof; Item 9: wherein the encapsulated explosive comprises a first encapsulated explosive and a second encapsulated explosive, and wherein the first encapsulated explosive has a higher detonation sensitivity than the second encapsulated explosive; Element 10: wherein the encapsulated explosive is a binary explosive comprising two components, each individually encapsulated; Element 11: wherein the encapsulated explosive is a binary explosive comprising two components, each individually encapsulated, and wherein the two components comprise at least one pair selected from the group consisting of ammonium nitrate / heavy oil, ammonium nitrate / nitromethane, ammonium nitrate / aluminum and Nitroethane / physical sensitizer, include; and element 12: wherein the encapsulated explosive has an average diameter of from about 10 nm to about 500 nm.

As a non-limiting example, exemplary combinations for A, B, C include: at least two of the elements 1-4; Element 5 in combination with at least one of elements 1-4; Element 6 in combination with at least one of elements 1-4; Element 5 in combination with element 6; Element 5 in combination with element 6 and at least one of elements 1-4; at least two of the elements 7-11; Element 5 in combination with at least one of elements 7-11; Element 6 in combination with at least one of elements 7-11; Element 5 in combination with element 6 and at least one of elements 7-11; Element 12 in combination with one of the above combinations; Element 5 in combination with element 12; and element 6 in combination with element 12.

One or more illustrative embodiments embodying the principles of the disclosure described herein are set forth below. For purposes of clarity, not all features of an actual implementation are described or shown in this application. It should be understood that in developing an actual embodiment embodying the present disclosure, numerous implementation-specific decisions must be made to achieve the goals of the developer, such as adhering to system-related, economic, regulatory, and other constraints, depending on the implementation and vary from time to time. However, while a developer's effort may be complex and time consuming, these efforts are still a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.

Note that if the term "about" precedes the beginning of a numeric listing, the term modifies all numbers in the numeric listing. For some numeric listings of ranges, some listed lower bounds may be greater than some listed upper bounds. One skilled in the art will recognize that the selected subset requires selection of an upper bound that exceeds the selected lower bound. Unless otherwise indicated, all numbers expressing amounts of ingredients, such as molecular weight, reaction conditions, and so forth, used in the present specification and claims are to be understood as modified by the term "about." Unless otherwise indicated, therefore, the numerical parameters set forth in the following description and the appended claims are approximations which may vary depending on the desired characteristics sought by the embodiments described herein. At least, and not in an attempt to limit the application of equivalence doctrine to the scope of the claim, each numerical parameter shall be interpreted at least considering the number of significant digits indicated and using ordinary rounding techniques.

Accordingly, the present disclosure is well suited to achieving the listed and the inherent objects and advantages. The particular embodiments disclosed above are illustrative only, and the present disclosure may be modified and implemented in a different but equivalent manner, as will be apparent to those skilled in the art having the benefit of the present teachings. Furthermore, as regards the details of the construction or design shown herein, no other limitations than those described in the following claims are provided. It is thus to be understood that the particular illustrative embodiments disclosed above may be changed, combined, or modified, and that all such variations are considered to fall within the scope and spirit of the present disclosure. The disclosure illustratively described herein may be suitably practiced by omitting any elements not specifically disclosed herein and / or any optional elements disclosed herein. Although compositions and methods have been described as comprising "comprising," "containing," or "including" the components and methods, the compositions and methods may also "consist" essentially of the various components and steps. All numbers and ranges disclosed above may vary by a certain amount. Whenever a numerical range having a lower limit and an upper limit is disclosed, any number and any range therein that falls within this range is expressly disclosed. In particular, each range of values disclosed herein (of the form "from about a to about b" or equivalently "from about a to b" or equivalently "about a-b") is cited as each number and range included in the broader range of values. In addition, the terms in the claims bear their simple, ordinary meaning unless expressly and clearly defined otherwise by the assignee. The indefinite articles "a," "an," "an," "an," "an" in the claims are defined to designate one or more of the elements to which they are prefixed. If there is an inconsistency in the use of a word or term in this specification and one or more patent or other documents that may be incorporated by reference, the definitions in accordance with this description shall apply.

Claims (20)

Method, comprising: Drilling a borehole penetrating a subterranean formation with a downhole cutting tool; Circulating a drilling fluid in the wellbore, the drilling fluid comprising a base fluid and an encapsulated explosive having an average diameter of from about 10 nm to about 20 micrometers; Triggering the detonation of the encapsulated explosive; and Detonating the encapsulated explosive near a portion of the subterranean formation adjacent to the downhole cutting tool. The method of claim 1, wherein the triggering of the detonation of the encapsulated explosive comprises irradiating the encapsulated explosive with electromagnetic radiation having a frequency of about 10 ⁶ Hz to about 10 ¹⁷ Hz. The method of claim 1, wherein triggering the detonation of the encapsulated explosive comprises crushing the encapsulated explosive between the well tool and the subterranean formation. The method of claim 1, wherein the triggering of the detonation of the encapsulated explosive comprises introducing cavitation into the drilling fluid. The method of claim 1, wherein the triggering of the detonation of the encapsulated explosive is intermittent. The method of claim 1, wherein the triggering of the detonation of the encapsulated explosive occurs upstream of the drill bit in a drill string coupled to the well tool. The method of claim 1, wherein the encapsulated explosive is at least one selected from the group consisting of a liposome, a cross-linked liposome, a nanoliposome, a polymer bubble, a dendritic polymer, a coated nanoparticle, a coated microparticle, an impregnated nanoparticle, an impregnated microparticle and any hybrid thereof. The method of claim 1, wherein the encapsulated explosive comprises at least one selected from the group consisting of thermite, octogen, pentaerythritol tetranitrate, tetranitrotoluene, an explosive nitroamine, lead picrate, mercury fulminate, iodine nitride, potassium perchlorate, ammonium perchlorate and the like and a combination thereof. The method of claim 1, wherein the encapsulated explosive comprises a first encapsulated explosive and a second encapsulated explosive, and wherein the first encapsulated explosive has a higher detonation sensitivity than the second encapsulated explosive. The method of claim 1, wherein the encapsulated explosive is a binary explosive comprising two components, each individually encapsulated. The method of claim 10, wherein the two components comprise at least one pair selected from the group consisting of ammonium nitrate / heavy oil, ammonium nitrate / nitromethane, ammonium nitrate / aluminum and nitroethane / physical sensitizer. The method of claim 1, wherein the encapsulated explosive has an average diameter of from about 10 nm to about 500 nm. Method, comprising: Drilling a wellbore penetrating a subterranean formation with a wellbore cutting tool operably coupled to a drill string and a receptacle coupled to at least one of the wellbore cutting tool and the drillstring, the receptacle containing a plurality of encapsulated explosives; Circulating a drilling fluid in the wellbore; Releasing at least a portion of the encapsulated explosives from the container and into the drilling fluid, the encapsulated explosives having an average diameter of from about 10 nm to about 20 microns; Triggering the detonation of the encapsulated explosives in the drilling fluid; and Detonating the encapsulated explosives near a portion of the subterranean formation adjacent to the downhole cutting tool. The method of claim 13, wherein the release of the at least part of the encapsulated explosives from the container is intermittent. The method of claim 13, wherein initiating the detonation of the encapsulated explosive comprises irradiating the encapsulated explosive with electromagnetic radiation having a frequency of about 10 ⁶ Hz to about 10 ¹⁷ Hz. The method of claim 13, wherein triggering the detonation of the encapsulated explosive comprises crushing the encapsulated explosive between the well tool and the subterranean formation. The method of claim 13, wherein triggering the detonation of the encapsulated explosive comprises subjecting the encapsulated explosive to cavitation. The method of claim 13, wherein triggering the detonation of the encapsulated explosive comprises contacting the encapsulated explosive with a chemical trigger. Method, comprising: Drilling a wellbore penetrating a subterranean formation with a wellbore cutting tool operably coupled to a drill string and a receptacle coupled to at least one of the wellbore cutting tool and the drillstring, the receptacle including a plurality of first encapsulated components ; Circulating a drilling fluid in the wellbore, the drilling fluid comprising a base fluid and a plurality of second encapsulated components, the first and second plurality of encapsulated components forming part of a binary explosive; Releasing at least a portion of the encapsulated components from the container into the drilling fluid; Triggering the detonation of the binary explosive by mixing the first encapsulated components with the second encapsulated components; and Detonating the binary explosive near a portion of the subterranean formation adjacent the well tool. The method of claim 19, wherein the releasing of the at least a portion of the first encapsulated component from the container is intermittent.

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