Patent classifications
G01V1/30
Mixed-phase source wavelet estimation from recorded seismic data
This disclosure presents processes and systems for estimating a source wavelet from seismic data recorded in a seismic survey of a subterranean formation. In one aspect, a base wavelet is determined based on recorded seismic traces obtained in a seismic survey of a subterranean formation. Processes and systems include a phase-only wavelet based on the base wavelet and the recorded seismic data. An estimated source wavelet is obtained by convolving the base wavelet with the phase-only wavelet. Properties of the subterranean formation are determined based on the estimated source wavelet and the recorded seismic data.
Inversion-based array processing for cement-bond evaluation with an LWD tool
Logging of data by a downhole tool disposed in a borehole may be affected by tool wave effects. The tool waves appear in the first echo of casing wave arrivals and the amplitudes may be much larger than casing wave arrivals. The estimates of casing wave amplitude are biased due to these tool wave arrivals when using conventional cement-bond logging (CBL) processing. An automated adaptive inversion-based array processing for CBL evaluation using a downhole tool provides an improvement in the calculation of a bonding index.
Method and system for identifying pore and fracture based on two-dimensional (2D) scan image of core
A method for identifying a pore and a fracture based on a two-dimensional (2D) scan image of a core includes: scanning a core to acquire an initial 2D image of the core; filtering the initial 2D image of the core to acquire a first 2D image of the core; segmenting the first 2D image of the core to acquire a second 2D image of the core; extracting center coordinates of all pixel points in each void space to acquire a centroid of the void space, and establishing a pore-fracture identification function of the void space; identifying the void space as a fracture if a value of the pore-fracture identification function is greater than a preset characterization value; and identifying the void space as a pore if the value of the pore-fracture identification function is not greater than the preset characterization value.
Method and system for identifying pore and fracture based on two-dimensional (2D) scan image of core
A method for identifying a pore and a fracture based on a two-dimensional (2D) scan image of a core includes: scanning a core to acquire an initial 2D image of the core; filtering the initial 2D image of the core to acquire a first 2D image of the core; segmenting the first 2D image of the core to acquire a second 2D image of the core; extracting center coordinates of all pixel points in each void space to acquire a centroid of the void space, and establishing a pore-fracture identification function of the void space; identifying the void space as a fracture if a value of the pore-fracture identification function is greater than a preset characterization value; and identifying the void space as a pore if the value of the pore-fracture identification function is not greater than the preset characterization value.
Seismic first breaks onset times determination by interface tracking using level-sets method
A method for determining and tracking an edge of first breaks is provided. The method includes obtaining seismic data associated with subsurface formations, the seismic data relating to a vibration contacting a plurality of portions of the subsurface formations, processing the seismic data to produce processed seismic data comprising one or more attributes, wherein the processed seismic data defines an edge characterizing a plurality of onset times, iteratively performing, using a level sets algorithm, a plurality of tracking operations on the processed seismic data to identify the edge characterizing a plurality of first breaks' onset times, and determining the edge as first breaks.
Seismic first breaks onset times determination by interface tracking using level-sets method
A method for determining and tracking an edge of first breaks is provided. The method includes obtaining seismic data associated with subsurface formations, the seismic data relating to a vibration contacting a plurality of portions of the subsurface formations, processing the seismic data to produce processed seismic data comprising one or more attributes, wherein the processed seismic data defines an edge characterizing a plurality of onset times, iteratively performing, using a level sets algorithm, a plurality of tracking operations on the processed seismic data to identify the edge characterizing a plurality of first breaks' onset times, and determining the edge as first breaks.
INTEGRATING WELLS INTO ADAPTIVE MULTI-SCALE GEOLOGICAL MODELING
Methods and systems, including computer programs encoded on a computer storage medium can be used for adaptive multi-scale geological modeling and well integration. The systems and methods are used to integrate seismic mapping data and well data for a subsurface region that includes a reservoir. The specification describes an example algorithm that is used to adaptively identify and isolate natural length scales in a seismic map. The identified natural length scales are then used to determine appropriate filtering of well information and ultimately achieve an automatic integration of orientation information from seismic map and well information.
Method, Apparatus, and Computer Program for Detecting One or More Objects in the Sea Floor
Embodiments deal with a method, a computer program as well as an apparatus for detecting one or more objects in the sea floor. The method comprises obtaining a receiver signal. The receiver signal is based on a scattering of multiple acoustic signals at the one or more objects in the sea floor. The receiver signal is generated by a plurality of receivers. The method further comprises grouping portions of the receiver signal to points of a detection grid. The detection grid represents a grid at the points of which the one or more objects are being localized. The method further comprises performing a travel time correction of the portions of the receiver signal with respect to the points of the detection grid. The method further comprises combining the travel time corrected portions of the receiver signal at the points of the detection grid. The method further comprises detecting the one or more objects at the points of the detection grid based on the combination of the travel time corrected portions of the receiver signal. The detection of the one or more objects is based on the scattering of the multiple acoustic signals at the one or more objects.
METHOD AND APPARATUS FOR IMPLEMENTING A HIGH-RESOLUTION SEISMIC PSEUDO-REFLECTIVITY IMAGE
A method for generating a high-resolution pseudo-reflectivity image of a subsurface region includes receiving seismic data associated with a subsurface region and captured by one or more seismic receivers, constructing a velocity model of the subsurface region based on the received seismic data, performing a seismic migration of the received seismic data based on the constructed velocity model to obtain migrated seismic data, computing polarized normal vectors associated with one or more subsurface reflectors of the subsurface region based on the migrated seismic data, and generating a pseudo-reflectivity image of the subsurface region based on both the computed polarized normal vectors.
1D MONO FREQUENCY RATIO LOG EXTRACTION WORKFLOW PROCEDURE FROM SEISMIC ATTRIBUTE DEPTH VOLUME
Methods and systems for determining a spectral ratio log using a time domain seismic image and a seismic velocity model are disclosed. The method includes determining a first mono-spectral seismic image and a second mono-spectral seismic image from the time domain seismic image. The method further includes determining a time domain spectral ratio image from the first mono-spectral seismic image and the second mono-spectral seismic image and transforming the time domain spectral ratio image into a depth domain spectral ratio image using the seismic velocity model. The method still further includes defining a wellbore path through the depth domain spectral ratio image and determining a spectral ratio log along the wellbore path from the depth domain spectral ratio.