Geophysical Data Processing

Leonardo Azevedo

Lecture #1 17 Sep. 2014

Introduction and Seismic Method

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leonardo.azevedo@ist.utl.pt

CERENA room: 2.1.11

Office hours: Wednesday from 3PM to 5PM

Grades:

70% - 2 tests during the semester OR Final Exam

30% - Assignment to be developed during the semester

mailto:leonardo.azevedo@ist.utl.pt

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Exploration workflow

Seismic Acquisition

Data Interpretation

Data Processing

Reservoir Modeling

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What is seismic processing

noise

hyperbolas

Acquisition

Recorded

raw data Final section for interpretation

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Seismic Method: Theoretical Background

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Seismic Method: Reflection Coefficients and Acoustic Impedance

Acoustic Impedance (Z)=density * velocityZ2-Z1

Z2+Z1Reflection Coefficient (RC)=

Herron (2011) Leonardo Azevedo, 2014

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Basic Processing Sequence

Improve signal quality: Increase signal-to-noise ratio

Remove source effect

Filter out noise

Time Correction

Sum traces

Spatial Correction

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Basic Processing Sequence

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Basic Processing Sequence: deconvolution

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Basic Processing Sequence: filtering

Land data ground roll

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Basic Processing Sequence: filtering

Marine data swell

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PS-wave stack profiles, in which (a) PS-wave stack profile without receiver static corrections, (b) PS-wave stack profile with

receiver static corrections and (c) PS-wave stack profile with PS-wave static and residual static corrections.

Basic Processing Sequence: statics correction

Chunying Yang, Yun Wang & Jun Lu, 2012, Application of Rayleigh waves on PS-wave static corrections, Journal of Geophysics and Engineering, 9,1.

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Basic Processing Sequence: migration