Seismic Reflection Processing
Seismic Reflection Processing

Author: S.K. Upadhyay

Publisher: Springer Science & Business Media

Published: 2013-03-09

Total Pages: 641

ISBN-13: 3662098431

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Seismic Reflection Processing coherently presents the physical concepts, mathematical details and methodology for optimizing results of reservoir modelling, under conditions of isotropy and anisotropy. The most common form of anisotropy - transverse isotropy - is dealt with in detail. Besides, practical aspects in reservoir engineering - such as interval isotropic or anisotropic properties of layered media; identifying lithology, pore-fluid types and saturation; and determining crack/fracture-orientations and density - form the core of discussions. This book incorporates significant new developments in isotropic and anisotropic reflection processing, while organizing them to improve the interpretation of seismic reflection data and optimizing the modeling of hydrocarbon reservoirs. It is written primarily as a reference and tutorial for graduate/postgraduate students and research workers in geophysics.

Frequency Dependent Seismic Reflection Analysis
Frequency Dependent Seismic Reflection Analysis

Author: Seung Chul Yoo

Publisher:

Published: 2010

Total Pages:

ISBN-13:

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To better study frequency related effects such as attenuation and tuning, we developed a frequency dependent seismic reflection analysis. Comprehensive tests on full waveform synthetics and observations from the Teal South ocean bottom seismic (OBS) data set confirmed that normal moveout (NMO) stretch could distort both frequency and amplitude information severely in shallow events and far offset traces. In synthetic tests, our algorithm recovered amplitude and frequency information accurately. This simple but robust target oriented NMO stretch correction scheme can be used on top of an existing seismic processing flow for further analyses. By combining the NMO stretch correction, spectral decomposition, and crossplots of amplitude versus offset (AVO) attributes, we tested the frequency dependent workflow over Teal south and Ursa field data sets for improved reservoir characterization. As expected from NMO stretch characteristics, low frequencies have been less affected while mid and high frequency ranges were affected considerably. In seismic attribute analysis, the AVO crossplots from spectrally decomposed prestack data confirmed the improved accuracy and effectiveness of our workflow in mid and high frequency regions. To overcome poor spectral decomposition results due to low signal to noise ratio (S/N) in the Teal South application, we also implemented a substack scheme that stacks adjacent traces to increase S/N ratio while reducing the amount of data to process and increasing the accuracy of the spectral decomposition step. Synthetic tests verified the effectiveness of this additional step. An application to the Ursa, Gulf of Mexico, deep water data set showed significant improvement in high frequency data while correcting biased low frequency information.

True-amplitude Processing Techniques for Marine, Crustal-reflection Seismic Data
True-amplitude Processing Techniques for Marine, Crustal-reflection Seismic Data

Author: Myung W. Lee

Publisher:

Published: 1990

Total Pages: 34

ISBN-13:

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Preserving the relative true-amplitude of seismic traces provides significant advantages for deep crustal investigations, particularly for the identification and analysis of deep reflections originating near the crust-mantle boundary. Preserving lateraI variations along deep reflections is also important for resolving amplitude changes due to geologic causes rather than to artifacts from recording or source conditions. Three relative true-amplitude processing methods (automatic edit, single-trace equalization, and a common-depth-point gather equalization) were applied to the 20-second seismic data of the Great lakes Multidisciplinary Program on Crustal Evolution in order to evaluate the performance of the different techniques. Particular attention was paid to the improvement of signal-to-noise ratio and to the preservation of latera I continuity of the deep reflections. This study indicates that the automatic editing procedure based on the median amplitude of a common-depth-point gather provided substantial signal-to-noise ratio improvement of the seismic profiles. Post-stack amplitude balancing was commonly necessary to maintain the lateral continuity of the deep reflections and to reduce migration noise. The results from these processing strategies confirm the existence of large differences in crustal reflectivities and in the shape and geometry of crust-mantle transition beneath central and western lake Superior.