Patent US3630281A successfully refreshed from Google Patents.
US3630281A
Expired / Lapsed
US
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Explosive fracturing of petroleum bearing formations
Assignee: BP America Production Co
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Filing: 1969-11-12
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Granted: 1971-12-28
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Expires: 1989-11-12
Abstract
Abstract This is a method for increasing the permeability of an underground formation adjacent a well bore by explosive fracturing. In one embodiment an explosive slurry, having selected fracturing fluid characteristics, is used to hydraulically fracture the formation and such explosive slurry is subsequently detonated. In another embodiment a sorbent solvent slug is injected down the tubing preceding the injection of the explosive slurry and a second such sorbent solvent immediately follows the explosive slurry. This avoids trapping of air or other gas and therefore prevents premature ignition or detonation of the explosive fracturing fluid.
Inventors
- 👤 Clarence R Fast
- 👤 George C Howard
- 👤 Morton A Mallinger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:02
CPC Classifications
E; E21; E21B; E21B33/00; E21B33/02; E21B33/08; E21B33/03; E21B33/068; E21B43/00; E21B43/25; E21B43/26; E21B43/263
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
22 words
A method as defined in claim 1 including the step of stemming said liquid explosive above said second slug of sorbent solvent.
Claim 2
Dependent Claim
24 words
A method as defined in claim 1 in which said sorbent solvent is selected from the group consisting of dibutyl phthalate, toluene and benzene.
Claim 3
Independent Claim
215 words
A method of using a liquid explosive to fracture an underground formation penetrated by a well bore in which a string of tubing is suspended which comprises: inserting a bottom plug in said string of tubing; placing a packer about the lower end of said string of tubing to seal the annulus between the string of tubing and the well bore; injecting a first slug of sorbent solvent on top of said bottom plug, the sorbent solvent used in this method being capable of desensitizing said liquid explosive which it contact; injecting said liquid explosive into said tubing string on top of said first slug, continuing injecting said liquid explosive until a selected amount has been injected and driving said bottom plug through the lower end of said tubing string; injecting a second slug of sorbent solvent into said string of tubing on top of said liquid explosive; inserting a top plug on top of said second slug; displacing said liquid explosive, said seCond slug and said top plug down said tubing string until said top plug reaches the lower end of said tubing string; retaining said top plug in the lower end of said tubing string; placing stemming material on top of said annulus packer and said top plug; thereafter detonating said explosive liquid.
Claim 4
Dependent Claim
56 words
A method as defined in claim 4 wherein said step of placing stemming material comprises separating the tubing string from a lower section thereof and injecting cement down through said tubing string and onto the top of said top plug and said packer; and removing said tubing string as said cement is displaced into said well.
Claim 5
Dependent Claim
25 words
A method as defined in claim 5 in which there is about 100 feet of cement placed above said annulus packer and said top plug.
Claim 6
Independent Claim
58 words
A method of explosively fracturing a formation penetrated by a well bore which comprises: a. injecting a liquid explosive into said well bore; b. immediately following step (a) injecting a slug of sorbent solvent, the sorbent solvent used in this method being capable of desensitizing said liquid explosive which it contacts; and c. thereafter detonating said liquid explosive.
Claim 7
Dependent Claim
43 words
A method as defined in claim 7 wherein said liquid explosive and said sorbent solvent is directed down through a string of tubing and including the step of inserting a top plug in said string of tubing above said slug of sorbent solvent.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-27 | 1975-06-28 | 1975-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-27 | 1979-06-28 | 1979-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-27 | 1983-06-28 | 1983-12-28 | $7700.00 | Window Closed / Lapsed |