New azimuthal binning for improved delineation of faults and fractures

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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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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Wrestling with 9/11: Immigrant Perceptions and Perceptions of Immigrants

MIGRATION LETTERS ◽

10.33182/ml.v3i2.63 ◽

2006 ◽

Vol 3 (2) ◽

pp. 107-124 ◽

Cited By ~ 1

Author(s):

Caroline Brettell

Keyword(s):

United States ◽

Immigration Policy ◽

Asian Indians ◽

World Trade Center ◽

The United States ◽

Fort Worth ◽

Foreign Born ◽

Immigrant Populations ◽

Trade Center ◽

The Impact

Soon after 9/11 a research project to study new immigration into the Dallas Fort Worth metropolitan area got under way. In the questionnaire that was administered to 600 immigrants across five different immigrant populations (Asian Indians, Vietnamese, Mexicans, Salvadorans, and Nigerians) between 2003 and 2005 we decided to include a question about the impact of 9/11 on their lives. We asked: “How has the attack on the World Trade Center on September 11, 2001 affected your position as an immigrant in the United States?” This article analyzes the responses to this question, looking at similarities and differences across different immigrant populations. It also addresses the broader issue of how 9/11 has affected both immigration policy and attitudes toward the foreign-born in the United States.

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NEODYMIUM ISOTOPE AND REE CONSTRAINTS ON PALEOZOIC SEDIMENT DISPERSAL TO THE FORT WORTH BASIN

10.1130/abs/2018sc-309799 ◽

2018 ◽

Author(s):

Ohood Alsalem ◽

◽

Majie Fan ◽

Asish Basu ◽

Tamara L. Adams

Keyword(s):

Fort Worth ◽

Sediment Dispersal ◽

Fort Worth Basin

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PALEOMAGNETIC TIMING OF DIAGENESIS IN THE UPPER ELLENBURGER GROUP CARBONATES SUGGEST A PERIODICALLY OPEN DIAGENETIC SYSTEM, FORT WORTH BASIN, TEXAS

10.1130/abs/2020sc-343412 ◽

2020 ◽

Author(s):

Devin Dennie ◽

◽

S. Johari Pannalal ◽

Earl B. Manning ◽

R. Douglas Elmore

Keyword(s):

Fort Worth ◽

Fort Worth Basin

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2015 US Geological Survey assessment of undiscovered shale-gas and shale-oil resources of the Mississippian Barnett Shale, Bend arch–Fort Worth Basin, Texas

AAPG Bulletin ◽

10.1306/0810171622017164 ◽

2018 ◽

Vol 102 (07) ◽

pp. 1299-1321 ◽

Cited By ~ 3

Author(s):

Kristen R. Marra

Keyword(s):

Shale Gas ◽

Geological Survey ◽

Barnett Shale ◽

Fort Worth ◽

Shale Oil ◽

Fort Worth Basin ◽

Oil Resources

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Acquisition of small surgical 3D seismic surveys in urban areas within the Fort Worth Basin

The Leading Edge ◽

10.1190/1.2542447 ◽

2007 ◽

Vol 26 (2) ◽

pp. 176-179

Author(s):

Thomas D. Bowman ◽

Wayne “Woody” Woodside ◽

Steve Culpepper

Keyword(s):

Urban Areas ◽

Fort Worth ◽

3D Seismic ◽

Seismic Surveys ◽

Fort Worth Basin

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Assessing Impacts of the High-Frequency Assimilation of Surface Observations for the Forecast of Convection Initiation on 3 April 2014 within the Dallas–Fort Worth Test Bed

Monthly Weather Review ◽

10.1175/mwr-d-18-0177.1 ◽

2018 ◽

Vol 146 (11) ◽

pp. 3845-3872 ◽

Cited By ~ 5

Author(s):

Nicholas A. Gasperoni ◽

Xuguang Wang ◽

Keith A. Brewster ◽

Frederick H. Carr

Keyword(s):

High Resolution ◽

High Frequency ◽

Weather Prediction ◽

National Research Council ◽

Future Application ◽

Fort Worth ◽

Sources Of Information ◽

Test Bed ◽

Convection Initiation ◽

The Impact

Abstract The Nationwide Network of Networks (NNoN) concept was introduced by the National Research Council to address the growing need for a national mesoscale observing system and the continued advancement toward accurate high-resolution numerical weather prediction. The research test bed known as the Dallas–Fort Worth (DFW) Urban Demonstration Network was created to experiment with many kinds of mesoscale observations that could be used in a data assimilation system. Many nonconventional observations, including Earth Networks and Citizen Weather Observer Program surface stations, are combined with conventional operational data to form the test bed network. A principal component of the NNoN effort is the quantification of observation impact from several different sources of information. In this study, the GSI-based EnKF system was used together with the WRF-ARW Model to examine impacts of observations assimilated for forecasting convection initiation (CI) in the 3 April 2014 hail storm case. Data denial experiments tested the impact of high-frequency (5 min) assimilation of nonconventional data on the timing and location of CI and subsequent storm evolution. Results showed nonconventional observations were necessary to capture details in the dryline structure causing localized enhanced convergence and leading to CI. Diagnosis of denial-minus-control fields showed the cumulative influence each observing network had on the resulting CI forecast. It was found that most of this impact came from the assimilation of thermodynamic observations in sensitive areas along the dryline gradient. Accurate metadata were found to be crucial toward the future application of nonconventional observations in high-resolution assimilation and forecast systems.

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