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Geol 755: Basin Analysis Geophysics Week 1. John N. Louie, Presenter Business Justification 3D Seismic Surveys Seismic Resolution. Business Justification. 3D seismic has substantially expanded global energy supply. Amoco development experience:. Business Justification.
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Geol 755: Basin AnalysisGeophysics Week 1 John N. Louie, Presenter Business Justification 3D Seismic Surveys Seismic Resolution Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Business Justification • 3D seismic has substantially expanded global energy supply. Amoco development experience: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Business Justification • 3D seismic has substantially reduced the cost of finding energy. Amoco international exploration increase in present value with 3D: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Business Justification • 3D seismic has substantially reduced the risk of exploring for energy. • Worldwide consortium experience: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Business Justification • 3D seismic has reduced the cost of finding energy, while dramatically increasing the volume of reserves found- leading to Asian economic boom 1999-2007: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Business Justification • 3D seismic has enabled Amoco to more than replace resources produced, keeping energy prices low: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
3D Seismic Surveys • From Seismological Grand Challenges in Understanding Earth’s Dynamic Systems: The petroleum industry relies on high-resolution seismic surveying to map oil and gas reservoirs at depths of up to 7 km. Though costly, 3D seismic yields the detail necessary to image the faults and complex sedimentary features that can trap energy reserves. This 3D "sonogram" traces the origin and properties of rock layers and reveals the most likely targets for drilling and extraction. Using 3D seismic imaging, the industry has cut the number of non-producing "dry" holes by more than half since 1990. Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions Ship image from B. Dragoset (2005), and Western Geophysical. "F3" seismic data and analysis from F. Aminzadeh and P. de Groot, (2006)/ Visualization by J. Louie.
3D Seismic Surveys • Sheriff (1992) addresses many benefits of 3-D seismic in Reservoir Geophysics; a few quotations from that volume follow: • 3-D seismic is an extremely powerful delineation tool, and spectacularly cost-effective, particularly when well costs are high. • The success is directly attributable to the better structural interpretation made possible by the 3-D survey. • The greatest impact of 3-D surveys has been the ability to match platform size, number of well slots, and production facilities to the more accurately determined field reserves. Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
3D Seismic Surveys • History of oil exploration and reserves in Campos Basin, from PetroBras: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Resolution of 3D Seismic Surveys • Factors in horizontal and vertical resolution: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Resolution of 3D Seismic Surveys • Wavelength increases with depth, so resolution decreases: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Resolution of 3D Seismic Surveys • Separating reflections vertically, in section: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Resolution of 3D Seismic Surveys • Horizontal resolution: Fresnel zones in map view Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Design of 3D Seismic Surveys • From Nexus Energy, Schlumberger. Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Resolution of 3D Seismic Surveys • Failure of 2D (NAZ- Narrow Azimuth) surveys- reflecting points are not in 2D section: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Resolution of 3D Seismic Surveys • “Marmousi” tank data illustrating 3D advantages: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Resolution of 3D Seismic Surveys • “Marmousi” tank data illustrating 3D advantages: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Resolution of 3D Seismic Surveys • 3D imaging will properly place dipping structures Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Resolution of 3D Seismic Surveys • 3D imaging achieves better continuity and fewer seismic artifacts. Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Resolution of 3D Seismic Surveys • Proper 3D imaging moves interfering reflections out of the way of a reservoir reflection: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Resolution of 3D Seismic Surveys • 3D gives proper dip on sections through salt dome: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Resolution of 3D Seismic Surveys • A channel invisible before 3D migration (left) is clear after 3D imaging (right): Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Design of 3D Seismic Surveys • From Nexus Energy, Schlumberger. Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Design of 3D Seismic Surveys • A geologic hypothesis for the target translates to design parameters of survey layout: line spacing, and shot spacing along the lines. Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Design of 3D Seismic Surveys • The more dip a target has, the higher the frequencies needed to image it. • High frequencies = better resolution. • High frequencies are difficult to get. Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Design of 3D Seismic Surveys • A geologic hypothesis for the target translates to design parameters of survey layout: line spacing, and shot spacing along the lines. Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
3D Seismic Data Volumes • Terminology for sections of seismic data volume: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
3D Seismic Data Volumes • Terminology for sections of seismic data volume: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Seismic Data Amplitudes • Histogram of seismic amplitudes in data volume: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions
Seismic Data Amplitudes • Representation of amplitudes in data volume: Taken From:Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions