David P. Craig
Engineers at Williams St, Westminster, CO
License number
Colorado 35143
Issued Date
Jan 24, 2001
Renew Date
Nov 1, 2015
Expiration Date
Oct 31, 2017
Type
Professional Engineer
Address
Address
14459 Williams St, Westminster, CO 80602
Professional information
Probabilistic Earth Model For Subterranean Fracture Simulation
US Patent:
8392165, Mar 5, 2013
Filed:
Nov 25, 2009
Appl. No.:
12/625914
Inventors:
David P. Craig - Thornton CO, US
Michael J. Eberhard - Thornton CO, US
Michael J. Eberhard - Thornton CO, US
Assignee:
Halliburton Energy Services, Inc. - Houston TX
International Classification:
G06G 7/48
US Classification:
703 10
Abstract:
Systems, methods, and instructions encoded in a computer-readable medium can perform operations related to generating a model of a subterranean formation based on a probabilistic earth model. An earth model including a probability distribution for a property of a subterranean region is received. A subterranean formation model is generated based on sampling the probability distribution for the property. The subterranean formation model includes information on boundaries of rock blocks of a formation in the subterranean region. The subterranean formation model may be used for simulating an injection treatment applied to the formation, for example, to predict fracture propagation in the formation. In some implementations, the subterranean formation model may be used for designing an injection treatment for the formation.
Methods And Apparatus For Estimating Physical Parameters Of Reservoirs Using Pressure Transient Fracture Injection/Falloff Test Analysis
US Patent:
7054751, May 30, 2006
Filed:
Mar 29, 2004
Appl. No.:
10/812210
Inventors:
David P. Craig - Thornton CO, US
Assignee:
Halliburton Energy Services, Inc. - Duncan OK
International Classification:
G01V 9/00, E21B 49/08
US Classification:
702 13
Abstract:
A before-closure pressure-transient leakoff analysis for a fracture-injection/falloff test is used to mitigate the detrimental effects of pressure-dependent fluid properties on the evaluation of physical parameters of a reservoir. A fracture-injection/falloff test consists of an injection of liquid, gas, or a combination (foam, emulsion, etc. ) containing desirable additives for compatibility with the formation at an injection pressure exceeding the formation fracture pressure followed by a shut-in period. The pressure falloff during the shut-in period is measured and analyzed to determine permeability and fracture-face resistance by preparing a specialized Cartesian graph from the shut-in data using adjusted pseudodata such as adjusted pseudopressure data and time as variables in a first method, and adjusted pseudopressure and adjusted pseudotime data as variables in a second method.
Probabilistic Simulation Of Subterranean Fracture Propagation
US Patent:
8386226, Feb 26, 2013
Filed:
Nov 25, 2009
Appl. No.:
12/626052
Inventors:
David P. Craig - Thornton CO, US
Assignee:
Halliburton Energy Services, Inc. - Houston TX
International Classification:
G06G 7/48
US Classification:
703 10, 703 2, 16625001, 1663081, 1662521, 1662501
Abstract:
Systems, methods, and instructions encoded in a computer-readable medium can perform operations related to stochastic simulation of subterranean fracture propagation. A plurality of subterranean formation models, each representing a subterranean formation, are analyzed to obtain information on predicted results of applying an injection treatment to the subterranean formation. Each of the analyzed subterranean formation models is generated by simulating forces acting on rock blocks of the subterranean formation during the injection treatment. Each simulation has an input parameter value determined for that simulation based on sampling a distribution of values for a characteristic of the subterranean formation. The characteristic may include, for example, a natural fracture parameter. The information on the predicted results of applying the injection treatment may include, for example, an output probability distribution.
Methods And Systems For Determining Reservoir Properties Of Subterranean Formations
US Patent:
7272973, Sep 25, 2007
Filed:
Oct 7, 2005
Appl. No.:
11/245893
Inventors:
David P. Craig - Thornton CO, US
Assignee:
Halliburton Energy Services, Inc. - Duncan OK
International Classification:
G01F 15/08
US Classification:
73200, 73861
Abstract:
Methods and systems are provided for evaluating subsurface earth oil and gas formations. More particularly, methods and systems are provided for determining reservoir properties such as reservoir transmissibilities and average reservoir pressures of a formation layer or multiple layers using fracture-injection/falloff test methods. The methods herein may use pressure falloff data generated by the introduction of an injection fluid at a pressure above the formation fracture pressure in conjunction with a fracture-injection/falloff test model to analyze reservoir properties. The fracture-injection/falloff test model recognizes that a new induced fracture creates additional storage volume in the formation and that a fracture-injection/falloff test in a layer may exhibit variable storage during the pressure falloff, and a change in storage may be observed at hydraulic fracture closure.
Method And An Apparatus For Detecting Fracture With Significant Residual Width From Previous Treatments
US Patent:
7774140, Aug 10, 2010
Filed:
Mar 30, 2004
Appl. No.:
10/813698
Inventors:
David P. Craig - Thornton CO, US
Assignee:
Halliburton Energy Services, Inc. - Duncan OK
International Classification:
G01V 1/40
US Classification:
702 11, 702 6, 702 12, 702 13, 7315251, 7315253, 1662501, 1663051
Abstract:
A refracture-candidate diagnostic test is an injection of compressible or slightly compressible fluid at pressures in excess of minimum in-situ stress and formation fracture pressure with pressure decline following injection test recorded to detect a fracture retaining residual width from previous stimulation treatments. The diagnostic consists of small volume injections with injection time being a small fraction of time required for compressible or slightly compressible reservoir fluid to exhibit pseudoradial flow. The fracture-injection portion of a test can be considered as occurring instantaneously. Data measurements are transformed into a constant rate equivalent pressure transformation to obtain adjusted pressures or adjusted pseudovariables which are analyzed to identify dual unit-slope before and after closure periods confirming a residual retaining width.
Generating Probabilistic Information On Subterranean Fractures
US Patent:
8437962, May 7, 2013
Filed:
Jul 16, 2010
Appl. No.:
12/837854
Inventors:
David P. Craig - Thornton CO, US
Assignee:
Halliburton Energy Services, Inc. - Houston TX
International Classification:
G06F 19/00, G06G 7/48, E21B 43/26
US Classification:
702 11, 703 10, 1663081
Abstract:
Systems, methods, and instructions encoded in a computer-readable medium can perform operations related to generating probabilistic information on characteristics of natural fractures of a subterranean formation. Fitted fracture models are generated based on microseismic event data for a subterranean region. The fitted fracture models represent estimated locations of fractures in the subterranean region. A distribution of fracture parameter values is generated based on the fitted fracture models. The distribution includes fracture parameter values and a probability associated with each fracture parameter value. Generating the fitted fracture models may include, for example, fitting a plane, a line or another type of equation to the measured locations of microseismic events. In some implementations, an injection treatment may be simulated and/or designed based on the probability distribution.
Refining Information On Subterranean Fractures
US Patent:
2011012, May 26, 2011
Filed:
Nov 25, 2009
Appl. No.:
12/626039
Inventors:
David P. Craig - Thornton CO, US
Assignee:
Halliburton Energy Services, Inc. - Houston TX
International Classification:
E21B 43/22, G01V 1/28, G06F 17/18, G06G 7/48, G05D 7/06, G05B 17/02
US Classification:
166270, 702 16, 703 6, 700283, 702181
Abstract:
Systems, methods, and instructions encoded in a computer-readable medium can perform operations related to refining information on characteristics of natural fractures of a subterranean formation. Fracture pattern models are generated based on sampling an initial distribution of values for a fracture parameter. Each fracture pattern model may include, for example, a model of natural fractures in a subterranean formation. Each fracture pattern model is compared to microseismic event data for a subterranean region. A refined distribution for the fracture parameter is generated based on the comparison. Generating the refined distribution may include, for example, selecting values of the fracture parameter from fracture pattern models that correlate with the microseismic event data. In some implementations, an injection treatment may be simulated and/or designed based on the refined distribution.
Methods And Systems For Determining Reservoir Properties Of Subterranean Formations With Pre-Existing Fractures
US Patent:
7389185, Jun 17, 2008
Filed:
Oct 7, 2005
Appl. No.:
11/245839
Inventors:
David P. Craig - Thornton CO, US
Assignee:
Halliburton Energy Services, Inc. - Duncan OK
International Classification:
G01V 9/00
US Classification:
702 13
Abstract:
Methods and systems are provided for evaluating subsurface earth oil and gas formations. More particularly, methods and systems are provided for determining reservoir properties such as reservoir transmissibilities and average reservoir pressures of formation layer(s) using quantitative refracture-candidate diagnostic methods. The methods herein may use pressure falloff data from the introduction of an injection fluid at a pressure above the formation fracture pressure to analyze reservoir properties. The model recognizes that a new induced fracture creates additional storage volume in the formation and that a quantitative refracture-candidate diagnostic test in a layer may exhibit variable storage during the pressure falloff, and a change in storage may be observed at hydraulic fracture closure. From the estimated formation properties, the methods may be useful for, among other things, determining whether a pre-existing fracture is damaged and evaluating the effectiveness of a previous fracturing treatment to determine whether a formation requires restimulation.
Simulating Subterranean Fracture Propagation
US Patent:
2013000, Jan 3, 2013
Filed:
Sep 12, 2012
Appl. No.:
13/611330
Inventors:
David P. Craig - Thornton CO, US
Assignee:
Halliburton Energy Services, Inc. - Houston TX
International Classification:
G06G 7/48
US Classification:
703 10
Abstract:
Systems, methods, and instructions encoded in a computer-readable medium can perform operations related to simulating subterranean fracture propagation. A subterranean formation model representing rock blocks of a subterranean formation is received. The subterranean formation model is used to predict a response of each rock block to one or more forces acting on the rock block during an injection treatment for the subterranean formation. The predicted responses of the rock blocks may include, for example, a fracture, a rotation, a displacement, a dilation of an existing fracture, and/or another type of response. In some implementations, an injection treatment may be designed for a subterranean formation based on the predicted response of the rock blocks.
Simulating Subterranean Fracture Propagation
US Patent:
2011012, May 26, 2011
Filed:
Nov 25, 2009
Appl. No.:
12/626153
Inventors:
David P. Craig - Thornton CO, US
Assignee:
Halliburton Energy Services, Inc. - Houston TX
International Classification:
E21B 43/26, E21B 43/00, E21B 43/25, G06G 7/57
US Classification:
1663081, 166 72, 1663051, 703 9
Abstract:
Systems, methods, and instructions encoded in a computer-readable medium can perform operations related to simulating subterranean fracture propagation. A subterranean formation model representing rock blocks of a subterranean formation is received. The subterranean formation model is used to predict a response of each rock block to one or more forces acting on the rock block during an injection treatment for the subterranean formation. The predicted responses of the rock blocks may include, for example, a fracture, a rotation, a displacement, a dilation of an existing fracture, and/or another type of response. In some implementations, an injection treatment may be designed for a subterranean formation based on the predicted response of the rock blocks.