A method includes receiving well log data for a plurality of wells. A flag is generated based at least partially on the well log data. The wells are sorted into groups based at least partially on the well log data, the flag, or both. A model is built for each of the wells based at least partially on the well log data, the flag, and the groups.

A method and apparatus for generating a fluid saturation model for a subsurface region. One example method generally includes obtaining a model of the subsurface region; for each of a plurality of fluid types: flooding the subsurface region model with the fluid type to generate a flood model; and running a trial petrophysical inversion with the flood model to generate a trial petrophysical model; identifying potential fluid contact regions in the trial petrophysical models; partitioning the subsurface region model at the identified potential fluid contact regions; and constructing the fluid saturation model from the partitioned subsurface region model.

The present invention belongs to the field of treatment for data identification and recording carriers, and specifically relates to a method and system for analyzing filling for a karst reservoir based on spectrum decomposition and machine learning, which aims to solve the problems that by adopting the existing petroleum exploration technology, the reservoir with fast lateral change cannot be predicted, and the development characteristics of a carbonate cave type reservoir in a large-scale complex basin cannot be identified. The method comprises: acquiring data of standardized logging curves; obtaining a high-precision 3D seismic amplitude data body by mixed-phase wavelet estimation and maximum posteriori deconvolution and enhancing diffusion filtering. According to the method and the system, the effect of identifying the development characteristics of the carbonate karst cave type reservoir in the large-scale complex basin can be achieved, and the characterization precision is improved.

The present disclosure describes methods and systems for downhole well integrity reconstruction in a hydrocarbon reservoir. One method for downhole well integrity reconstruction in a hydrocarbon reservoir includes: positioning, a laser head at a first subterranean location, wherein the laser head is attached to a tubular inside of a wellbore; directing, by the laser head, a laser beam towards a leak on the wellbore; and sealing the leak using the laser beam.

A well log is scanned for one or more dimensions that describe one or more features of a well. Each dimension includes a plurality of values in a numerical format that represents each dimension. A missing value is detected in a first plurality of values of a first dimension of the well log. The first dimension of the well log is transformed, in response to the missing value, into a first image that visually depicts the first dimension including the first plurality of values and the missing value. Based on the first image and based on an image analysis algorithm a second image is created that visually depicts the first plurality of values and includes a found depiction visually depicting a found value in place of the missing value. The found depiction is converted, based on the second image, into a first value in the numerical format.

The present disclosure describes methods and systems for downhole well integrity reconstruction in a hydrocarbon reservoir. One method for downhole well integrity reconstruction in a hydrocarbon reservoir includes: positioning, a laser head at a first subterranean location, wherein the laser head is attached to a tubular inside of a wellbore; directing, by the laser head, a laser beam towards a leak on the wellbore; and sealing the leak using the laser beam.

A global objective function is initialized to an initial value. A particular model simulation process is executed using prepared input data. A mismatch value is computed by using a local function to compare an output of the particular model simulation process to corresponding input data for the particular model simulation process. Model objects associated with the particular model simulation process are sent to another model simulation process. An optimization process is executed to predict new values for input data to reduce the computed mismatch value.

A method of predicting a property of an earth formation includes: injecting a fluid into at least one pre-existing feature of the formation at a plurality of constant pressures or flow rates; measuring a response from the at least one pre-existing feature at each of the plurality of constant pressures or flow rates; and estimating at least one property of the at least one pre-existing feature based on the response. An apparatus for predicting a property of an earth formation is also disclosed.

Offshore electromagnetic (EM) reservoir monitoring systems and methods, including a system with a light source producing a light beam and an EM sensor array deployed at the bottom of a body of water and above one or more subsea regions of interest, the array coupled to the light source with an optical fiber. An EM sensor modulates the interrogation light beam in response to an EM signal induced into the subsea formation by an EM source. The system further includes a processor controlling the light source, processing modulated light received from the array, and collecting data with the array to produce EM surveys, each EM survey based on data sets collected at different times. The EM sensor is physically isolated from a surrounding subsea environment. The surveys are combined to produce a time lapse earth model of the regions of interest.

Apparatus having a focused transducer and methods of operating a focused transducer downhole in a well can provide high resolution downhole imaging. In various embodiments, a focused transducer is used for imaging downhole in a well in which the imaging is based on a seismoelectric effect. In various embodiments, a focused transducer is used for imaging downhole in a well in which the imaging is based on an electroacoustic effect. Additional apparatus, systems, and methods are disclosed.