A combining mechanism for borehole logging tool data that uses density data from a logging tool to inform the geometry of an acoustic-based or ultrasound-based data inversion is provided, comprising: at least one mechanism for converting three-dimensional density data into a three-dimensional density model; at least one mechanism for converting three-dimensional density model into a three-dimensional acoustic impedance model; and, at least one mechanism for processing acoustic data using said three-dimensional acoustic impedance model to produce an interpretable data log. A method of using density data from a logging tool to inform the geometry of an acoustic-based or ultrasound-based data inversion is also provided, comprising: converting three-dimensional density data into a three-dimensional density model; converting three-dimensional density model into a three-dimensional acoustic impedance model; and, processing acoustic data using said three-dimensional acoustic impedance model to produce an interpretable data log.

Disclosed are systems and methods for processing acoustic logging information with automatic dispersion matching. The method comprises obtaining, from an acoustic logging tool, acoustic waveforms from within a borehole, applying dispersion analysis to the acoustic data to extract a slowness-frequency response, calculating a slowness density log of the slowness-frequency response, obtaining an initial shear slowness estimate based on the slowness density, generating a dispersion model comprising model parameters, and performing a dispersion response auto match inversion to minimize the difference between the slowness-frequency response and the dispersion model in order to obtain a final shear slowness estimate.

A method of predicting model parameters (R.sub.1, R.sub.2, R.sub.3, . . . ) of a geological formation under investigation, wherein said geological formation is distinguished by reservoir parameters including observable data parameters and the model parameters (R.sub.1, R.sub.2, R.sub.3, . . . ) to be predicted, comprises the steps of calculating at least one model constraint (M.sub.1, M.sub.2, M.sub.3, . . . ) of the model parameters (R.sub.1, R.sub.2, R.sub.3, . . . ) by applying at least one rock physics model (f.sub.1, f.sub.2, f.sub.3, . . . ) on the model parameters (R.sub.1, R.sub.2, R.sub.3, . . . ), said at least one model constraint (M.sub.1, M.sub.2, M.sub.3, . . . ) including modelled data of at least one of the data parameters, and applying an inverse model solver process on observed input data (d.sub.1, d.sub.2, d.sub.3, . . . ) of at least one of the data parameters, including calculating predicted model parameters, which comprise values of the model parameters (R.sub.1, R.sub.2, R.sub.3, . . . ) which give a mutual matching of the input data and the modelled data, wherein the modelled data are provided with probability distribution functions, the inverse model solver process is conducted based on the probability distribution functions, wherein multiple predicted values of the model parameters are obtained comprising values of the model parameters (R.sub.1, R.sub.2, R.sub.3, . . . ) which give the mutual matching of the input data and the modelled data, and model probabilities of the predicted model parameters are calculated in dependency on the probability distribution functions.

Apparatus and methods to generate a two-dimensional image of the well can include control of measurements in a well to generate a log of the well and use of such measurements and/or logs with a log of a reference well. The boundary positions of layers of the well can be correlated with corresponding boundary positions from the reference well. Such apparatus and methods or similar apparatus and methods can be implemented in a variety of applications.

An illustrative method that includes positioning an acoustic transducer downhole substantially parallel to a borehole wall, thereby creating a fluid layer between the wall and the acoustic transducer, and measuring an acoustic impedance at the surface of the acoustic transducer at a resonance frequency of the fluid layer, thereby determining an acoustic impedance of the formation.

A computer-implemented method for updating subsurface models including: using an offset continuation approach to update the model, and at each stage defining a new objective function where a maximum offset for each stage is set, wherein the approach includes, performing a first stage iterative full wavefield inversion with near offset data, as the maximum offset, to obtain velocity and density or impedance models, performing subsequent stages of iterative full wavefield inversion, each generating updated models, relative to a previous stage, wherein the subsequent stages include incrementally expanding the maximum offset until ending at a full offset, wherein a last of the stages yields finally updated models, the subsequent stages use the updated models as starting models, and the full wavefield inversions include constraining scales of the velocity model updates at each stage of inversion as a function of velocity resolution; and using the finally updated models to prospect for hydrocarbons.

The present invention discloses a land seismic exploration method, electronic equipment and a readable storage medium, which belongs to the field of land seismic exploration technology. The land seismic exploration method, includes: detecting the first component seismic wave transmitted to the surface of the ground by the vibration generated at a preset position of the ground or surface; detection of the second component of seismic wave transmitted by the vibration to the air above the surface; Calculate the surface parameters within the set range of the preset position according to the first seismic wave and the second component of seismic wave; The underground velocity model and density model are calculated according to the surface parameters. Using the same meteorological conditions, the sound velocity and density of the air are consistent, and the second seismic wave that penetrates the earth surface and reaches the air is detected.

A device, computer program and related method for processing a first seismic signal that includes identifying one portion of a second seismic signal and determining a length of a seismic wavelet. It is also possible to train a neural network by using a plurality of sub-portions of said portion a input variables and at least one second piece of information as a target variable. Said sub-portions of the portion have a length dependent on the length of the seismic wavelet determined. Finally, the method includes determining at least one first piece of geological information based on the first seismic signal using said trained neural network.

A reflection full waveform inversion method updates separately a density model and a velocity model of a surveyed subsurface formation. The method includes generating a model-based dataset corresponding to the seismic dataset using a velocity model and a density model to calculate an objective function measuring the difference between the seismic dataset and the model-based dataset. A high-wavenumber component of the objective function's gradient is used to update the density model of the surveyed subsurface formation. The model-based dataset is then regenerated using the velocity model and the updated density model, to calculate an updated objective function. The velocity model of the surveyed subsurface formation is then updated using a low-wavenumber component of the updated objective function's gradient. A structural image of the subsurface formation is generated using the updated velocity model.

An x-ray based litho-density tool for measurement of formation surrounding a borehole is provided, the tool including at least an internal length comprising a sonde section, wherein said sonde section further comprises an x-ray source; at least one radiation measuring detector; at least one source monitoring detector; a plurality of sonde-dependent electronics; and a reference detector, wherein the reference detector is used to monitor the output of the x-ray source such that the reference detector's output effects corrections to the outputs of the detectors used to measure the density of the materials surrounding the borehole in order to correct for variations in the x-ray source output. Tool logic electronics, PSUs, and one or more detectors used to measure borehole standoff such that other detector responses may be compensated for tool standoff are also provided. Shielding, through-wiring, wear-pads that improve the efficacy and tool functionality are also described and claimed.