Abstract: Methods are provided for adaptive optimization of enhanced oil recovery project performance under uncertainty. Predictive physics-based reservoir simulation is used to estimate performance of the project. Input parameters of the model are divided into control variables and uncertain variables. The reservoir model is optimized to obtain values of control variables maximizing mean value of a chosen performance metric under initial uncertainty of formation and fluid properties. An efficient frontier can characterize dependence between the optimized mean value of the performance metric and its uncertainty expressed by the standard deviation. Global sensitivity analysis (GSA) is then applied to quantify and rank contributions from uncertain input parameters to the standard deviation of the optimized values of the performance metric. Additional measurements can be performed to reduce uncertainty in the high-ranking parameters.

Abstract: A formation is characterized by generating a model of the formation that characterizes the formation in a manner consistent with all measurements, thereby permitting a computation or prediction of how the formation will respond to disturbances or stimuli such as fluid injection for production, carbon-dioxide injection for sequestration, current injection, etc. The formation is described with a fundamental set of microscopic parameters such that quantities relevant to petrophysical response at a continuum or macroscopic level can be derived from them. Values for various formation parameters are determined, as are values for various field variables.

Abstract: Method for using sensitivity analysis to inform the design and performance of a well test are provided. In one embodiment, a method includes providing a reservoir model of pressure transient behavior and performing a sensitivity analysis to identify an input parameter of the reservoir model that can be estimated from pressure transient test data collected from a well location. This method also includes using the results of the sensitivity analysis to design a pressure transient well test for measuring the identified input parameter. Other methods and systems are also disclosed.

Abstract: Apparatus and methods for delivering and placing proppant to a subterranean formation fracture including identifying control variables and uncertain parameters of the proppant delivery and placement, optimizing a performance metric of the proppant delivery and placement under uncertainty, calculating sensitivity indices and ranking parameters according to a relative contribution in total variance for an optimized control variable, and updating a probability distribution for parameters, repeating optimizing comprising the probability distribution, and evaluating a risk profile of the optimized performance metric using a processor. Some embodiments may deliver proppant to the fracture using updated optimized values of control variables.

Abstract: A method for evaluating wellbore integrity including introducing a drill to a surface of a casing encompassing an annulus, enclosing the drill in a housing hydraulically isolating the surface, drilling through the casing and into cement surrounding the casing, observing a pressure of the fluid, and using the pressure observation and a drill position to evaluate a presence of a defect and a location of the defect. Apparatus for evaluating wellbore integrity including a probe comprising a drill, wherein the probe is hydraulically isolated from the wellbore, a valve that encompasses the drill, a pressure gauge to measure the pressure of the fluid within the housing, a pressure gauge to measure the pressure in the system outside the housing, and equipment to compare the pressure measurements and the position of the drill and to evaluate a presence and a location of the defect.

Abstract: A method, apparatus, and program product utilize global sensitivity analysis (GSA) based on variance decomposition to calculate and apportion the contributions to a total variance of a measurement signal from uncertain input parameters of a subsurface model in connection with designing targeted surveys. Through the use of global sensitivity analysis in this manner, the geometry for a survey may be determined based on a desired target of the design, e.g., based on spatial properties (e.g., reservoir zone of interest) and/or physical properties (e.g., porosity, fluid density, rock physics properties) to select locations (e.g., source-receiver pairs) with greater uncertainty contributions from parameter group(s) of interest.

Abstract: A method for evaluating wellbore integrity including introducing a drill to a surface of a casing encompassing an annulus, enclosing the drill in a housing hydraulically isolating the surface, drilling through the casing and into cement surrounding the casing, observing a pressure of the fluid, and using the pressure observation and a drill position to evaluate a presence of a defect and a location of the defect. Apparatus for evaluating wellbore integrity including a probe comprising a drill, wherein the probe is hydraulically isolated from the wellbore, a valve that encompasses the drill, a pressure gauge to measure the pressure of the fluid within the housing, a pressure gauge to measure the pressure in the system outside the housing, and equipment to compare the pressure measurements and the position of the drill and to evaluate a presence and a location of the defect.