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US 10,119,392 B2Granted
Determining depth of loss zones in subterranean formations
AssigneeHalliburton Energy Services, Inc.
InventorsKrishna Babu Yerubandi, Mark Ryan Savery
Life of this patent
Estimating the term…
Abstract
Methods of locating a loss zone in a wellbore in a subterranean formation including determining a calculated wellhead pressure, calculating a wellhead pressure differential, calculating a flow rate loss, estimating a loss zone depth, determining a modified calculated wellhead pressure, and calculating a modified wellhead pressure differential until the modified wellhead pressure differential corresponds to a loss zone location in the wellbore.
Claims22
A method of locating a loss zone in a subterranean formation comprising:
- (a) providing a wellbore in the subterranean formation having a tubular therein, wherein an annulus is formed between the tubular and a face of the wellbore;
- (b) introducing a treatment fluid into the wellbore through the tubular and displacing the treatment fluid up through the annulus;
- (c) logging real-time measurements during introducing and displacing the treatment fluid, the real-time measurements selected from the group consisting of actual wellhead pressure (AWP), treatment fluid inlet density (ρi), inlet flow rate ({dot over (Q)}i), outlet flow rate ({dot over (Q)}o), treatment fluid inlet viscosity (μi), and any combination thereof;
- (d) determining a calculated wellhead pressure (CWP) based on the real-time measurements of step (c);
- (e) calculating a wellhead pressure differential (ΔWP) based on Formula 1:
- ΔWP=|CWP−AWP|;
- (f) calculating a flow rate loss ({dot over (Q)}loss) based on Formula 2:
- {dot over (Q)}loss={dot over (Q)}i−{dot over (Q)}o;
- (g) estimating a loss zone depth (dest) at a depth along the wellbore,
- wherein estimating the loss zone depth comprises receiving a user input indicating a predetermined loss zone depth value;
- (h) determining a modified calculated wellhead pressure (CWPmod) based on hydraulic calculations, wherein the flow rate loss ({dot over (Q)}loss) and the estimated loss zone depth (dlz) are used as inputs, wherein determining the modified calculated wellhead pressure comprises modifying the calculated wellhead pressure using the predetermined loss zone depth value from the received user input;
- (i) calculating a modified wellhead pressure differential (ΔWPmod);
- and
- (j) repeating steps (g) through (i) until the modified wellhead pressure differential (ΔWPmod) is in the range of 0 to a user defined maximum, whereby the estimated loss zone depth (dest) substantially corresponds to a loss zone location (dlz) in the wellbore.
11 more elements
A method of locating a loss zone in a subterranean formation comprising:
- (a) providing a wellbore in the subterranean formation having a tubular therein, wherein an annulus is formed between the tubular and a face of the wellbore;
- (b) introducing a treatment fluid into the wellbore through the tubular and displacing the treatment fluid up through the annulus;
- (c) logging real-time measurements during introducing and displacing the treatment fluid, the real-time measurements selected from the group consisting of actual wellhead pressure (AWP), treatment fluid inlet density (ρi), inlet flow rate ({dot over (Q)}i), outlet flow rate ({dot over (Q)}o), treatment fluid inlet viscosity (μi), and any combination thereof;
- (d) determining a calculated wellhead pressure (CWP) based on the real-time measurements of step (c);
- (e) calculating a wellhead pressure differential (ΔWP) based on Formula 1:
- ΔWP=|CWP−AWP|;
- (f) calculating a flow rate loss ({dot over (Q)}loss) based on Formula 2:
- {dot over (Q)}loss={dot over (Q)}i−{dot over (Q)}o;
- (g) estimating a loss zone depth (dest) at a depth along the wellbore,
- wherein estimating the loss zone depth comprises receiving a user input indicating a predetermined loss zone depth value;
- (h) determining a modified calculated wellhead pressure (CWPmod) based on hydraulic calculations, wherein the flow rate loss ({dot over (Q)}loss) and the estimated loss zone depth (dlz) are used as inputs, wherein determining the modified calculated wellhead pressure comprises modifying the calculated wellhead pressure using the predetermined loss zone depth value from the received user input;
- (i) calculating a modified wellhead pressure differential (ΔWPmod);
- and
- (j) repeating steps (g) through (i) until the modified wellhead pressure differential (ΔWPmod) is in the range of 0 to a user defined maximum, whereby the estimated loss zone depth (dest) substantially corresponds to a loss zone location (dlz) in the wellbore, wherein the modified wellhead pressure differential is adjusted based on a change in the estimated loss zone depth;
- and
- (k) performing a remedial operation to at least partially seal the loss zone location (dlz) in the wellbore.
13 more elements
A method of locating a loss zone in a subterranean formation comprising:
- (a) providing a first wellbore in the subterranean formation having a tubular therein, wherein an annulus is formed between the tubular and a face of the wellbore,
- wherein subterranean formation comprises an oilfield;
- (b) introducing a first treatment fluid into the first wellbore through the tubular and displacing the first treatment fluid up through the annulus;
- (c) logging real-time measurements during introducing and displacing the treatment fluid, the real-time measurements selected from the group consisting of actual wellhead pressure (AWP), first treatment fluid inlet density (ρi), inlet flow rate ({dot over (Q)}i), outlet flow rate ({dot over (Q)}o), treatment fluid inlet viscosity (μi), and any combination thereof;
- (d) determining a calculated wellhead pressure (CWP) based on the real-time measurements of step (c);
- (e) calculating a wellhead pressure differential (ΔWP) based on Formula 1:
- ΔWP=|CWP−AWP|;
- (f) calculating a flow rate loss ({dot over (Q)}loss) based on Formula 2:
- {dot over (Q)}loss={dot over (Q)}i−{dot over (Q)}o;
- (g) estimating a loss zone depth (dest) at a depth along the wellbore,
- wherein estimating the loss zone depth comprises receiving a user input indicating a predetermined loss zone depth value;
- (h) determining a modified calculated wellhead pressure (CWPmod) based on hydraulic calculations, wherein the flow rate loss ({dot over (Q)}loss) and the estimated loss zone depth (dlz) are used as inputs, wherein determining the modified calculated wellhead pressure comprises modifying the calculated wellhead pressure using the predetermined loss zone depth value from the received user input;
- (i) calculating a modified wellhead pressure differential (ΔWPmod);
- and
- (j) repeating steps (g) through (i) until the modified wellhead pressure differential (ΔWPmod) is in the range of 0 to a user defined maximum, whereby the estimated loss zone depth (dest) substantially corresponds to a loss zone location (dlz) in the first wellbore;
- (k) establishing an oilfield loss zone location (dfield lz) for the oilfield that is equivalent to the location of the loss zone in the wellbore;
- (l) providing a second wellbore in the subterranean formation having the oilfield loss zone location (dfield lz) therein;
- (m) performing a preventative operation to at least partially seal the oilfield loss zone location (dfield lz) in the second wellbore.
15 more elements
Dependencies are inferred from the claim text.