Warping prestack imaged data to improve stack quality and resolution

Gabriel Perez; Kurt J. Marfurt

doi:10.1190/1.2829986

Warping prestack imaged data to improve stack quality and resolution

Geophysics ◽

10.1190/1.2829986 ◽

2008 ◽

Vol 73 (2) ◽

pp. P1-P7 ◽

Cited By ~ 5

Author(s):

Gabriel Perez ◽

Kurt J. Marfurt

Keyword(s):

Vertical Component ◽

Vertical Position ◽

Fort Worth ◽

Seismic Attribute ◽

Prestack Migration ◽

Fort Worth Basin ◽

Attribute Analysis ◽

Recent Developments ◽

Land Survey ◽

Corrected Data

Accurate seismic imaging requires that a geologic feature be located at the same lateral and vertical position in images obtained by 3D prestack migration from different data bins, such as common-offset or common-angle subvolumes. Misalignment of those images degrades the quality of the stack. For dipping reflectors and lateral discontinuities, imperfect imaging causes both lateral and vertical misalignment. In current practice, the vertical component of the misalignment is used to estimate updates in velocity and other imaging parameters; the lateral component is largely ignored. We show that recent developments in seismic-attribute analysis allow us to examine the lateral misalignment of prestack volumes with similar resolution to that achieved in examining vertical moveout. To measure lateral moveout, we pick maxima from local 2D crosscorrelations computed between slices from 3D attribute volumes. We then use these measurements to correct for the lateral misalignment by applying a warping procedure to the corresponding slices in the prestack migrated seismic data. We apply our technique to a 3D land survey acquired over the Fort Worth basin in Texas, and obtain subtle, but potentially important, improvements in the quality and resolution of the stack as well as in the attribute images computed from the corrected data.

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On: “3-D seismic imaging and seismic attribute analysis of genetic sequences deposited in low‐ accommodation conditions” (B. A. Hardage, D. L. Carr, D.E. Lancaster, J. L. Simmons Jr., D. S. Hamilton, R. Y. Elphick, K. L. Oliver, and R. A. Johns, GEOPHYSICS, 61, 1351–1362)

Geophysics ◽

10.1190/1.1444300 ◽

1997 ◽

Vol 62 (6) ◽

pp. 1996-1998

Author(s):

Miodrag M. Roksandić

Keyword(s):

Fort Worth ◽

Seismic Attribute ◽

Gas Field ◽

Fort Worth Basin ◽

Multidisciplinary Study ◽

Depositional Processes ◽

Attribute Analysis ◽

Reservoir Compartmentalization ◽

Central Texas ◽

Genetic Sequences

The paper deals with the results of a multidisciplinary study of the Bend Conglomerate (Middle Pennsylvanian fluvio‐deltaic clastics) in a portion of Boonsville gas field in the Fort Worth Basin of North‐Central Texas, especially with those related to the Caddo sequence, at the top of the Bend Conglomerate. The purpose of the study was “to determine how modern geophysical, geological, and engineering techniques could be combined to understand the mechanisms by which fluvio‐deltaic depositional processes create reservoir compartmentalization in a low‐ to moderate‐accommodation basin.” According to Hardage et al. (1996), complexly arranged key chronostratigraphic surfaces are major controls on compartmentalization and architecture of reservoirs. These key chronostratigraphic surfaces are flooding surfaces, maximum flooding surfaces, and erosion surfaces.

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New azimuthal binning for improved delineation of faults and fractures

Geophysics ◽

10.1190/1.2813136 ◽

2008 ◽

Vol 73 (1) ◽

pp. S7-S15 ◽

Cited By ~ 17

Author(s):

Gabriel Perez ◽

Kurt J. Marfurt

Keyword(s):

Azimuthal Velocity ◽

Image Point ◽

Fort Worth ◽

Fracture Detection ◽

Prestack Migration ◽

Fort Worth Basin ◽

Strike Direction ◽

Scattered Energy ◽

Imaging Approach ◽

The Impact

We suggest and test a new way to define azimuth binning in Kirchhoff prestack migration. With this new definition, we sort seismic data by the azimuth of the average travel path traversed from the source to the subsurface image point and back to the receiver, rather than the azimuth between source and receiver on the surface of the earth. This approach avoids mixing the typically weaker side-scattered energy with the stronger in-plane reflections, thereby providing greater leverage in identifying image contributions from out-of-the-plane steeply dipping reflectors, fractures and faults. We examine the impact of this new imaging approach combined with analysis of seismic attributes that have proved useful for fracture detection, on data from the Fort Worth Basin, Texas, United States. We find that the image of features such as reflectors and discontinuities focus into azimuths perpendicular to the strike of each feature. The discrimination achieved in the azimuthal domain allows for an increased resolution in analysis of geologic features according to their strike direction. It should also result in improved residual azimuthal velocity analysis.

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Seismic Attribute Analysis of 3D Prestack Migration

EAGE/SEG Workshop - Depth Imaging of Reservoir Attributes ◽

10.3997/2214-4609.201406702 ◽

1998 ◽

Author(s):

W. E. A. Rietveld ◽

K. J. Marfurt ◽

J. H. Kommedal

Keyword(s):

Seismic Attribute ◽

Prestack Migration ◽

Attribute Analysis

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Attribute expression of fault-controlled karst — Fort Worth Basin, Texas: A tutorial

Interpretation ◽

10.1190/int-2013-0188.1 ◽

2014 ◽

Vol 2 (3) ◽

pp. SF91-SF110 ◽

Cited By ~ 38

Author(s):

Jie Qi ◽

Bo Zhang ◽

Huailai Zhou ◽

Kurt Marfurt

Keyword(s):

Pattern Recognition ◽

Structural Control ◽

Large Scale ◽

Karst Collapse ◽

Fort Worth ◽

Specific Expression ◽

Karst Terrain ◽

Fort Worth Basin ◽

Pattern Recognition Problem ◽

Attribute Analysis

Much of seismic interpretation is based on pattern recognition, such that experienced interpreters are able to extract subtle geologic features that a new interpreter may easily overlook. Seismic pattern recognition is based on the identification of changes in (1) amplitude, (2) phase, (3) frequency, (4) dip, (5) continuity, and (6) reflector configuration. Seismic attributes, which providing quantitative measures that can be subsequently used in risk analysis and data mining, partially automate the pattern recognition problem by extracting key statistical, geometric, or kinematic components of the 3D seismic volume. Early attribute analysis began with recognition of bright spots and quickly moved into the mapping of folds, faults, and channels. Although a novice interpreter may quickly recognize faults and channels on attribute time slices, karst terrains provide more complex patterns. We sought to instruct the attribute expression of a karst terrain in the western part of the Fort Worth Basin, Texas, United States of America. Karst provides a specific expression on almost every attribute. Specifically, karst in the Fort Worth Basin Ellenburger Group exhibits strong dip, negative curvature, low coherence, and a shift to lower frequencies. Geomorphologically, the inferred karst geometries seen in our study areas indicate strong structural control, whereby large-scale karst collapse is associated with faults and where karst lineaments are aligned perpendicularly to faults associated with reflector rotation anomalies.

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Spectral Characteristics of Ground Motion from Induced Earthquakes in the Fort Worth Basin, Texas, Using the Generalized Inversion Technique

Bulletin of the Seismological Society of America ◽

10.1785/0120200097 ◽

2020 ◽

Vol 110 (5) ◽

pp. 2058-2076 ◽

Cited By ~ 1

Author(s):

SeongJu Jeong ◽

Brian W. Stump ◽

Heather R. DeShon

Keyword(s):

Seismic Hazard ◽

Spectral Characteristics ◽

Vertical Component ◽

Sedimentary Basins ◽

Fort Worth ◽

Induced Earthquakes ◽

Fort Worth Basin ◽

Inversion Technique ◽

Generalized Inversion ◽

Generalized Inversion Technique

ABSTRACT A generalized inversion technique (GIT) is applied to local seismic data from 90 induced earthquakes (ML 2.0–3.9) in the Fort Worth Basin (FWB) of north Texas to separate path, site, and source characteristics and to improve local seismic hazard assessment. Seismograms from three earthquake sequences on spatially separated basement faults are recorded on 66 temporary stations. Because of the lack of hard-rock recording sites within the sedimentary basin, we developed a site correction method for the appropriate GIT process. At about 30 km distance from the hypocenters, we observed a change in spectral attenuation and thus focus data analysis within this distance range. The estimated quality factors for S and P waves result in a QS that is larger than QP which we interpret as a result of concentrations of crustal pore fluids or partial fluid-saturated material along the path; an interpretation consistent with fluid-rich sedimentary rocks in the FWB. Strong site amplifications as much as five times on horizontal components reflect the thick sediments in the basin. A limited number of sites exhibit amplification or deamplification on the vertical component that limits the use of horizontal-to-vertical spectral ratio methods for characterizing the site effect relative to the site effects estimated by GIT. Stress drops for all earthquakes range from 1.18 and 21.73 MPa with a mean of 4.46 MPa, similar to values reported for tectonic intraplate events. The stress-drop values suggest that strong motion and seismic hazard from the injection-induced earthquake in the FWB are comparable to those for tectonic earthquakes. The strong site amplification and fluid effects on propagation attenuation may be crucial factors to take into account for estimating seismic hazards of induced earthquakes in sedimentary basins.

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