DETAILED ACTION
The present application is a 371 national stage entry of PCT/US24/34284.
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Election/Restrictions
Applicant’s election without traverse of Group I (Claims 1-11) in the reply filed on September 12, 2025 is acknowledged.
Claims 12-20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim.
Claim Objections
Claim 1 is objected to because of the following informalities: inconsistent terminology. Claim 1 recites “a subterranean formation” in line 1; Claim 1 then recites “the formation” in line 5. Appropriate correction is required.
Claim Rejections - 35 USC § 112(b)
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-11 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites the following: A method for hydraulically fracturing a subterranean formation traversed by a wellbore, comprising:
mixing a gelling agent and water to form a base fluid;
adding a gas and a proppant to the base fluid to form a foam fluid;
alternating injecting into the formation the base fluid and the foam fluid;
repeating the alternating injecting;
forming regions of higher proppant concentration; and
forming channels adjacent to the regions.
During method step 1, a base fluid is formulated comprising a gelling agent and water. During method step 2, a foam fluid is formulated by adding a gas and a proppant to the base fluid from step 1. Based on the claimed invention, it appears that one final fluid (i.e. the foam fluid) remains to be injected into the subterranean formation. Thus, it is unclear whether there are two distinct fluid compositions or one final fluid composition, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention.
Moreover, it the Applicant intends to claim two distinct fluid compositions, it is unclear how much base fluid remains as the base fluid versus how much base fluid is combined with the additional components (i.e. a gas and a proppant) to formulate the foam fluid be subsequently injected into the subterranean formation separately from the base fluid.
Claims 1-11 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites the limitation “forming regions of higher proppant concentration” in line 7. The term “higher” in claim 1 is a relative term which renders the claim indefinite. It is unclear what regions are considered low versus high proppant concentration, because the claim only recites regions with “higher” proppant concentration. The term “higher” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention.
Moreover, it is unclear how the channels are formed adjacent to the regions. Thus, Claim 1 is incomplete for omitting essential steps, such omission amounting to a gap between the steps. See MPEP § 2172.01. The omitted steps are: formation of channels (See Applicant’s Specification, filed 06/17/2024: Fig. 2; [0020]).
Based on the Applicant’s original disclosure, the Examiner suggests the following (or substantially similar) amendment to Claim 1:
1. (Currently Amended) A method for hydraulically fracturing a subterranean formation traversed by a wellbore, comprising:
forming a base fluid comprising a gelling agent and water ;
forming a foam fluid comprising the gelling agent, water, a gas and a proppant ;
alternating injecting into the subterranean formation the base fluid and the foam fluid;
repeating the alternating injecting;
forming agglomerated proppant regions of higher proppant concentration; and
forming channels adjacent to the regions by injecting the base fluid at a faster flow rate than a flow rate of the foam fluid.
OR
Based on the Applicant’s original disclosure, the Examiner suggests the following (or substantially similar) amendment to Claim 1:
1. (Currently Amended) A method for hydraulically fracturing a subterranean formation traversed by a wellbore, comprising:
mixing a gelling agent and water to form a base fluid;
adding a gas and a proppant to the base fluid to form a foam fluid;
pulse injecting into the subterranean formation the foam fluid;
repeating the pulse injecting;
forming pulsed agglomerated proppant regions of higher proppant concentration; and
forming channels with lesser or no proppant concentration adjacent to the regions due to the pulse injecting.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1-3 and 7-10 are rejected under 35 U.S.C. 103 as being unpatentable over Nguyen et al. (US 2019/0106619) in view of Pantsurkin et al. (US 2017/0121593).
Claim 1. A method for hydraulically fracturing a subterranean formation traversed by a wellbore, comprising:
mixing a gelling agent and water to form a base fluid;
adding a gas and a proppant to the base fluid to form a foam fluid;
alternating injecting into the formation the base fluid and the foam fluid;
repeating the alternating injecting;
forming regions of higher proppant concentration; and
forming channels adjacent to the regions.
Nguyen discloses a method to maintain and/or enhance the conductivity of a fracture in a subterranean formation (Abstract), the method comprising: introducing a proppant-free fracturing fluid into the subterranean formation, wherein the proppant-free fluid may comprise an aqueous base fluid (e.g., water) ([0011] – [0013]; [0031]; Claim 12); then introducing a proppant-laden fracturing fluid with a spacer fluid intermittently into the subterranean formation, wherein the proppant-laden fluid comprises an aqueous base fluid and proppant particulates, and wherein the spacer fluid comprises an aqueous base fluid and thermoplastic particulates that may be carried in a foam carrier fluid that may include gelling agents ([0011]; [0013]; [0029]; Claims 12, 14); and introducing the proppant-laden fracturing fluid and the spacer fluid intermittently into the at least one fracture such that the proppant particulates aggregate in the at least one fracture and are surrounded and neutrally suspended by the spacer fluid, wherein the degradable thermoplastic particulates are degradable to create proppant-free channels in the at least one fracture ([0036] – [0037]; Claim 12).
Nguyen does not expressly disclose: repeating the alternating injecting; forming regions of higher proppant concentration; and forming channels adjacent to the regions.
However, Pantsurkin teaches injecting fracturing fluid into a wellbore in a pulse mode, with an injection pulse mode providing at least one pulse of injecting fracturing fluid with a proppant and at least one pulse of injecting fracturing fluid without the proppant (Claim 1); increasing the length of pulse of the proppant tail-in portion (109) injection, wherein during the tail-in phase of hydraulic fracturing, additional amount of the proppant, from 5,000 to 50,000 liters, can be injected (Figs. 1-3; [0057]); wherein the fracturing fluid is injected in the pulse mode to form clusters (islands) (112) of the proppant in the fracture, with channels (107) forming between them (Fig. 1; [0054]). It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the method in Nguyen by injecting the treatment fluid(s) in a pulse mode, as taught by Pantsurkin, in order to form proppant clusters with channels that optimize fracture conductivity and enhance formation fluid production ([0017]).
Claim 2. Nguyen in view of Pantsurkin teach The method of claim 1. Regarding the limitation: wherein a pulse of the foam fluid has a duration of about 5 to about 300 seconds, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the range of time that the proppant-laden fracturing fluid and the spacer fluid are intermittently introduced into the subterranean formation in Nguyen to the range as claimed, because it has been held that “where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.” In re Aller, 220 F. 2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Claim 3. Nguyen in view of Pantsurkin teach The method of claim 1. Regarding the limitation: wherein a pulse of the base fluid has a duration of about 5 to about 300 seconds, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the range of time that the proppant-free fluid and/or proppant-laden fracturing fluid and the spacer fluid are intermittently introduced into the subterranean formation in Nguyen to the range as claimed, because it has been held that “where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.” In re Aller, 220 F. 2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Claim 7. Nguyen in view of Pantsurkin teach The method of claim 1. Regarding the limitation: wherein the foam fluid further comprises fibers, Pantsurkin teaches that the proppant-free fluid and/or proppant fluid may comprise fibers ([0045] – [0047]; [0051]; [0073]). It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the foam fluid in Nguyen with fibers, as taught by Sun, in order to prevent proppant clusters from spreading by reinforcing the proppant pack and to optimize channels ([0051]; [0073]).
Claim 8. Nguyen in view of Pantsurkin teach The method of claim 1. Nguyen discloses wherein the proppant comprises silica sand, resin coated sands, sintered ceramic materials, fused synthetic ceramic materials, light weight nut shells, or a combination thereof ([0015]).
Claim 9. Nguyen in view of Pantsurkin teach The method of claim 1. Nguyen discloses wherein the proppant is coated ([0019]).
Claim 10. Nguyen in view of Pantsurkin teach The method of claim 1. Nguyen discloses wherein the gas comprises nitrogen ([0011]).
Claims 4-6 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Nguyen et al. (US 2019/0106619) in view of Pantsurkin et al. (US 2017/0121593), further in view of Sun et al. (US 2021/0215028).
Claim 4. Nguyen in view of Pantsurkin teach The method of claim 1. Nguyen discloses that the carrier fluid may include gelling agents ([0013]), but Nguyen does not expressly disclose: wherein the gelling agent comprises polyacrylamide, polyacrylamide derivatives, or combinations thereof. However, Sun teaches a method of fracturing a subterranean formation, the method comprising: introducing a first fracturing fluid that includes natural gas into the formation at a rate and pressure sufficient to create a complex fracture in the formation; then introducing a second fracturing fluid into the formation, wherein the second fracturing fluid comprises water, a gelling agent, a foaming agent, natural gas, and proppant particulates ([0015]). Sun teaches that the gelling agent may include polymers, such as polyacrylamide ([0044] – [0045]). It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the gelling agent(s) in Nguyen with polyacrylamide, as taught by Sun, in order to increase the viscosity of the treatment fluid ([0043]).
Claim 5. Nguyen in view of Pantsurkin teach The method of claim 1. Nguyen discloses that the carrier fluid may include gelling agents ([0013]), but Nguyen does not expressly disclose: wherein the gelling agent comprises guar, guar derivatives, viscoelastic surfactant, xanthan gum, hydroxyethyl cellulose, or a combination thereof. However, Sun teaches that the gelling agent may include polymers, such as guar gum and derivatives thereof ([0044] – [0045]). It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the gelling agent(s) in Nguyen with guar, as taught by Sun, in order to increase the viscosity of the treatment fluid ([0043]).
Claim 6. Nguyen in view of Pantsurkin teach The method of claim 1. Nguyen discloses that the carrier fluid may be foamed and may include surfactants ([0011]) and/or foamers ([0013]), but Nguyen does not expressly disclose: wherein the foam fluid further comprises a foaming agent. However, Sun teaches that the second fracturing fluid includes a surfactant or foaming agent to promote and stabilize the foam in the second fracturing fluid ([0050] – [0051]). It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the surfactants and/or foamers in Nguyen with a foaming agent, as taught by Sun, in order to stabilize the foam in the treatment fluid ([0050]).
Claim 11. Nguyen in view of Pantsurkin teach The method of claim 1. Nguyen discloses that the carrier fluid may be foamed and may include stabilizers ([0011]), but Nguyen does not expressly disclose: wherein the base fluid further comprises a foam stability control agent. However, Sun teaches that the second fracturing fluid may include stabilizers ([0047]) as well as a surfactant or foaming agent to promote and stabilize the foam in the second fracturing fluid ([0050] – [0051]). It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the carrier fluid in Nguyen with a foam stabilizer and/or surfactant or foaming agent, as taught by Sun, in order to stabilize the foam in the treatment fluid ([0050]).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure: Litvinets et al. (US 2015/0167443); Nguyen et al. (US 2016/0153273); Auzerais et al. (US 2018/0298271).
Litvinets discloses a method of fracturing treatment comprising injecting a proppant-free first treatment fluid into a subterranean formation penetrated by a wellbore to initiate fractures therein then injecting a second proppant-laden treatment fluid comprising proppant and extrametrical material, wherein the proppant concentration and extrametrical material may be pulsed to consolidate proppant into a network of proppant pillars with flow channels between the pillars (Abstract; [0030]; [0031]) that prevents the fracture from closing ([0059]; [0060]). Litvinets discloses that the treatment may be optimized by selection of proppant composition, shape, and size ([0018]; [0095]) as well as that of the extrametrical material ([0019]).
Nguyen teaches a method of forming a proppant pack, by initiating a fracture in a subterranean formation with a pad fluid, then alternating a treatment slurry fluid and spacer fluid (Abstract; [0011]; [0028]; [0029]).
Auzerais discloses a multistage treatment fluid comprising one or more stages of a polymer-forming composition and one or more stages of a spacer fluid; wherein the treatment fluid is injected in stages that alternate between the water and polymer-forming composition (114) and the spacer fluid (112) through a wellbore (102) and into the fracture openings (104), with the end result of generating clusters or islands of polymerized material (108) spaced apart by a filler material (110) deposited from the spacer fluid (112) and into formation (106); wherein the filler material may be pumped out or dissolved to produce flow channels between the pillars generated from the polymer-forming material ([0025]; [0030]; [0040]; [0045]; [0070]). Auzerais discloses that the multistage treatment fluids may include one or more stages containing energized fluids or foams including a gaseous component such as nitrogen, carbon dioxide, air, or a combination thereof ([0020]), wherein specifically the spacer fluid may be a foam having a gaseous internal phase such as nitrogen or carbon dioxide ([0028]). Auzerais further discloses that the multistage treatment fluids may contain a predetermined sequence of stages of fluid volumes or “pulses,” including one or more stages of a polymer-forming composition that create a series of polymer pillars that function to prop open fractures and provide regions of increased permeability through the hydraulically fractured network ([0021]).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Crystal J. Lee whose telephone number is (571)272-6242. The examiner can normally be reached M-F from 8:00am - 5:00pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Doug Hutton can be reached at (571) 272-4137. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/CRYSTAL J LEE/Primary Examiner, Art Unit 3674