Patent application number | Description | Published |
20080209997 | System, method, and apparatus for fracture design optimization - A method for optimizing fracture treatments includes interpreting a nominal pump schedule corresponding to a nominal value for each fracture control parameter. The method further includes interpreting environmental variables, and interpreting probability distributions for each of the environmental variables that is uncertain. The method further includes defining an objective function such as a net present value of each fracture treatment over a 365 day period following the fracture treatment. The method includes determining an optimal value for each fracture control parameter according to the objective function by determining the fracture control parameter values that yield the best mean net present value given the variability in the environmental variables as described by their probability distributions. | 09-04-2008 |
20080300793 | AUTOMATED FIELD DEVELOPMENT PLANNING OF WELL AND DRAINAGE LOCATIONS - A hybrid evolutionary algorithm (“HEA”) technique is described for automatically calculating well and drainage locations in a field. The technique includes planning a set of wells on a static reservoir model using an automated well planner tool that designs realistic wells that satisfy drilling and construction constraints. A subset of these locations is then selected based on dynamic flow simulation using a cost function that maximizes recovery or economic benefit. In particular, a large population of candidate targets, drain holes and trajectories is initially created using fast calculation analysis tools of cost and value, and as the workflow proceeds, the population size is reduced in each successive operation, thereby facilitating use of increasingly sophisticated calculation analysis tools for economic valuation of the reservoir while reducing overall time required to obtain the result. In the final operation, only a small number of full reservoir simulations are required for the most promising FDPs. | 12-04-2008 |
20090271233 | VALUING FUTURE INFORMATION UNDER UNCERTAINTY - The invention relates to a method of performing an oilfield operation of an oilfield having at least one well having a wellbore penetrating a subterranean formation for extracting fluid from an underground reservoir therein. The method steps include analyzing the oilfield operation to generate a decision tree comprising a first decision and a second decision, wherein a first outcome of the first decision dictates acquiring information relevant to the second decision, formulating a figure of merit of the oilfield operation according to the decision tree based on the information and uncertainties associated with the oilfield, determining a value of the figure of merit by modeling the oilfield operation using statistical sampling, and performing the oilfield operation upon making the first decision based on the value of the figure of merit. | 10-29-2009 |
20090299636 | METHOD FOR SELECTING WELL MEASUREMENTS - A method of determining a selection of well measurements and/or their respective control parameters is described based on a global target having predetermined sensitivities to a multitude of uncertainties associated with input variables to a model including the step of ranking measurements and control parameters in accordance with their capability to reduce the uncertainties of input variables identified as most sensitive input variables through simulations using the model or a reduced variant of the model. | 12-03-2009 |
20100185427 | AUTOMATED FIELD DEVELOPMENT PLANNING - A system for automatically optimizing a Field Development Plan (FDP) for an oil or gas field uses a fast analytic reservoir simulator to dynamically model oil or gas production from the entire reservoir over time in an accurate and rapid manner. An objective function defining a Figure of Merit (FoM) for candidate FDPs is maximized, using an optimization algorithm, to determine an optimized FDP in light of physical, engineering, operational, legal and engineering constraints. The objective function for the Figure of Merit, e.g., net present value (NPV) or total production for a given period of time, relies on a production forecast from the fast analytic reservoir simulator for the entire FDP. The position, orientation and dimensions of analytical model elements for the subsurface oil or gas field, as well as the physical properties associated with these elements, correlate to connected flow volume data from a Shared Earth Model (SEM). Uncertainty in the SEM is considered via stochastic sampling. In the presence of uncertainty, the optimum Field Development Plan (FoM) is selected by maximizing an objective function defining a risk-based Figure of Merit for the entire FDP. | 07-22-2010 |
20100318337 | METHOD, APPARATUS AND SYSTEM FOR MODELED CARBON SEQUESTRATION - Methods, systems and apparatuses are provided for facilitating sequestration of naturally occurring or anthropogenic carbon dioxide. The methods, systems and apparatuses of the present invention include a software interface for facilitating an exchange of data among associated simulators which simulate various steps of the carbon sequestration process. | 12-16-2010 |
20110119037 | PRODUCTION OPTIMIZATION FOR OILFIELDS USING A MIXED-INTEGER NONLINEAR PROGRAMMING MODEL - A system performs production optimization for oilfields using a mixed-integer nonlinear programming (MINLP) model. The system uses an offline-online approach to model a network of interdependent wells in an online network simulator while modeling multiple interdependent variables that control performance as an offline MINLP problem. The offline model is based on production profiles established by assuming decoupled wells in the actual network of wells. In one example, an amount of lift-gas to inject and settings for subsurface chokes are optimized. An offline solver optimizes variables through the MINLP model. Offline results are used to prime the online network simulator. Iteration between the offline and online models results in a convergence, at which point values for the interdependent variables are communicated to the real-world oilfield to optimize hydrocarbon production. Priming the online model with results from the offline model drastically reduces computational load over conventional techniques. Additional techniques anneal initial data starting points, smooth pressure differences, and adapt constraint values to further reduce computational intensity. | 05-19-2011 |
20110270591 | PROXY METHODS FOR EXPENSIVE FUNCTION OPTIMIZATION WITH EXPENSIVE NONLINEAR CONSTRAINTS - A method for optimizing expensive functions with expensive nonlinear constraints. The method includes selecting sample data for evaluating an expensive function of a simulation, generating a function proxy model for the expensive function and a constraint proxy model for an expensive nonlinear constraint of the expensive function using an approximation scheme, calculating a first solution point for the simulation using the proxy models, and evaluating the expensive function at the first solution point using the sample data. When the expensive function and the proxy models do not converge at the first solution point, the method further includes adding the first solution point to the sample data for updating the proxy models. The method further includes repeating the calculation and evaluation of solution points until the expensive function and the proxy models converge and, following convergence, identifying an optimal solution of the function proxy model and the constraint proxy model. | 11-03-2011 |
20120095603 | LIFT-GAS OPTIMIZATION WITH CHOKE CONTROL - A method of optimizing production of wells using choke control includes generating, for each well, an intermediate solution to optimize the production of each well. The generating includes using an offline model that includes a mixed-integer nonlinear program solver and includes using production curves based on a choke state and a given wellhead pressure. The method further includes calculating, using a network model and the intermediate solution of each well, a current online wellhead pressure for each well. The method further includes setting the intermediate solution as a final solution based on determining that a difference between the current online wellhead pressure of each well and a prior online wellhead pressure of each well is less than a tolerance amount. The method further includes adjusting, using the final solution of each well, at least one operating parameter of the wells. | 04-19-2012 |
20130304617 | METHOD OF VALUATION OF GEOLOGICAL ASSET OR INFORMATION RELATING THERETO IN THE PRESENCE OF UNCERTAINTIES - Methods are disclosed for assigning a value to a geological asset or information relating thereto in the presence of private and public sources of uncertainties. The private and public uncertainties associated with a geological asset or information associated therewith are defined, and private uncertainties are assigned a subjective probability representing the best state of knowledge currently available. A multi-dimensional valuation-time lattice is constructed using the subjective probabilities for the private uncertainties and using risk-neutral probabilities for the public uncertainties. A backward recursion through the multi-dimensional lattice is performed in order to generate a present value for the asset given the present information available. During the backward recursion, a tally of delta hedging coefficients is generated and stored in order to provide an operational “map” or “decision pathway” should the project move forward. | 11-14-2013 |
20140156238 | OPTIMIZATION WITH A CONTROL MECHANISM USING A MIXED-INTEGER NONLINEAR FORMULATION - A method of optimizing production of wells using choke control includes generating, for each well, an intermediate solution to optimize the production of each well. The generating includes using an offline model that includes a mixed-integer nonlinear program solver and includes using production curves based on a choke state and a given wellhead pressure. The method further includes calculating, using a network model and the intermediate solution of each well, a current online wellhead pressure for each well. The method further includes setting the intermediate solution as a final solution based on determining that a difference between the current online wellhead pressure of each well and a prior online wellhead pressure of each well is less than a tolerance amount. The method further includes adjusting, using the final solution of each well, at least one operating parameter of the wells. | 06-05-2014 |
20140262235 | METHOD OF OPTIMIZATION OF FLOW CONTROL VALVES AND INFLOW CONTROL DEVICES IN A SINGLE WELL OR A GROUP OF WELLS - A method and an apparatus for managing a subterranean formation including collecting information about a flow control valve in a wellbore traversing the formation, adjusting the valve in response to the information wherein the adjusting includes a Newton method, a pattern search method, or a proxy-optimization method. In some embodiments, adjusting comprises changing the effective cross sectional area of the valve. A method and an apparatus for managing a subterranean formation including collecting information about an inflow control valve in a wellbore traversing the reservoir and controlling the valve, wherein the control includes a direct-continuous approach or a pseudo-index approach. | 09-18-2014 |