An acoustic logging method includes obtaining first horizontal transverse isotropy (“HTI”) angles resulting from a time domain HTI algorithm. The method further includes obtaining one or more second HTI angles resulting from a frequency domain HTI algorithm. The method further includes generating a first HTI anisotropy log including a relative angle log based on the first and second HTI angles. The method further includes generating a first color map of the first HTI anisotropy log and displaying the first color map.

A method for determining an internal multiple attenuated seismic image is disclosed. The method includes obtaining a seismic dataset composed of a plurality of seismic traces and for each seismic trace determining an internal multiple trace based, at least in part, on a nested truncated correlation and a bounded convolution of the seismic trace with itself. The method further includes determining an internal multiple attenuated seismic trace based, at least in part, on subtracting the internal multiple trace from the seismic trace and combining the internal multiple attenuated seismic trace to form the internal multiple attenuated seismic image. A system including a seismic source, a plurality of seismic receivers, and a seismic processor for executing the method is disclosed.

A method is described for seismic amplitude analysis including receiving a seismic dataset representative of a subsurface volume of interest wherein the seismic dataset includes an angle or angle stack dimension; select a plurality of sets of sub-cubes in the seismic dataset wherein each set of sub-cubes includes a plurality of the angles or the angle stacks; compute standard score statistics for each of the plurality of sub-cubes; identify amplitude variation with angle (AVA) anomalies based on the standard score statistics for each of the set of sub-cubes; classify the AVA anomalies to generate classified AVA anomalies; and displaying, on a user interface, the classified AVA anomalies as a graphical display. The method is executed by a computer system.

The approaches presently disclosed provide for fault-interpretation in a seismic volume with computer assistance, allowing automatic or semi-automatic determination of a fault surface and associated displacement across the fault. The present fault interpretation approach uses pattern matching algorithms and does not require prior interpretation of the stratigraphic horizons. In certain implementations the fault interpretation approach estimates the 3D fault surface as part of a joint fault surface location and displacement optimization process.

Methods and systems, including computer programs encoded on a computer storage medium can be used to preserve edges while performing Gaussian grid smoothing of noise components in subsurface grids to generate geological maps. A subsurface grid is generated from data indicating properties of subsurface formations. A weighting grid is generated by: i) receiving seismic data representing the subsurface formations; ii) generating seismic attributes associated with discontinuities in the subsurface formations; and iii) assigning a particular weight value to weighting grid points that the seismic attributes associated with discontinuities in the subsurface formations indicate the presence of a discontinuity. The subsurface grid is processed by iteratively computing local averages of grid points in the subsurface grid using a compact Gaussian filter weighted by values in the weighting grid. A geological map of subsurface formations is generated based on the filtered subsurface grid.

A method and apparatus for imaging seismic data includes obtaining an initial model of a subsurface formation, wherein the model includes a plurality of nodes that form at least part of a grid; an initial dip value for the nodes; and a set of origin coordinates for each of the nodes; performing bottom-up ray tracing for each node in the model, resulting in a set of arrival coordinates for each node; identifying a plurality of gathers from the seismic data; for each gather: calculating a set of midpoint coordinates; defining a midpoint vicinity surrounding the set of midpoint coordinates; identifying the nodes having arrival coordinates within the midpoint vicinity; and estimating a unique aperture for each of the gathers based on the respective origin coordinates; storing the estimated apertures in a table; and generating a subsurface volume or image with subsurface reflectors determined with apertures of the respective gathers.

Apparatus, computer instructions and method for deghosting seismic data related to a subsurface of a body of water. The method includes inputting data recorded by detectors that are towed by a vessel, the data being associated with waves travelling from the subsurface to the detectors; applying a migration procedure to the data to determine a first image of the subsurface; applying a mirror migration procedure to the data to determine a second image of the subsurface; joint deconvoluting the first image and the second image for deghosting a reflectivity of the subsurface; and generating a final image of the subsurface based on the deghosted reflectivity of the joint deconvoluting step.

Apparatus, computer instructions and method for deghosting seismic data related to a subsurface of a body of water. The method includes inputting data recorded by detectors that are towed by a vessel, the data being associated with waves travelling from the subsurface to the detectors; applying a migration procedure to the data to determine a first image of the subsurface; applying a mirror migration procedure to the data to determine a second image of the subsurface; joint deconvoluting the first image and the second image for deghosting a reflectivity of the subsurface; and generating a final image of the subsurface based on the deghosted reflectivity of the joint deconvoluting step.

The present invention provides a method and apparatus for enhanced monitoring of induced seismicity and industrial vibration to comprehensively measure all aspects of potentially damaging motion. The invention utilizes various combinations of multi-component low frequency linear seismic sensors and multi-component rotational seismic sensors. Sensors are jointly deployed in arrays on the free surface of the earth, and/or in arrays of shallow monitoring holes, which may be intended to be permanent deployments. The method has a wide range of risk/damage monitoring applications for industrial activity, and in oil and gas exploration and production for seismic surveys, hydraulic fracturing, and waste injection wells. This abstract is not intended to be used to interpret or limit the claims of this invention.

A method includes the steps of receiving a wavefield generated by reflections in a subsurface region and recorded by a plurality of seismic receivers and compensating the recorded wavefield for amplitude attenuation. The method further includes modelling a propagation of a source wavefield forward in time, from an initial time-state to a final time-state through an earth model that is representative of the subsurface region, wherein the modelling includes phase and amplitude effects of attenuation and modelling a propagation of the compensated recorded wavefield backward in time from a final time-state to an earlier time-state through the earth model, wherein the subsurface region has an absorption characteristic that dampens the recorded wavefield wherein the modelling includes phase and amplitude effects of attenuation.