Seismic data processing strategies and results are strongly affected by field acquisition parameters.It may not be altered in any way and proper attribution is required.
And I have a passion for the seismic method Let this be an ode to philo seismos. The seismic method has three principal applications: (a) Delineation of nearsurface geology for engineering studies, and coal and mineral exploration within a depth of up to 1 km: The seismic method applied to the near-surface studies is known as engineering seismology. Hydrocarbon exploration and development within a depth of up to 10 km: The seismic method applied to the exploration and development of oil and gas fields is known as exploration seismology. Investigation of the earths crustal structure within a depth of up to 100 km: The seismic method applied to the crustal and earthquake studies is known as earthquake seismology. This book is devoted to application of the reflection seismic method to the exploration and development of oil and gas fields. ![]() Figure I-1 shows a seismic section from the Gulf of Mexico, nearly 40 km in length. Approximate depth scale indicates a sedimentary section of interbedded sands and shales down to 8 km. Note from this earth image a salt sill embedded in the sedimentary sequence. This allocthonous salt sill has a rugose top and a relatively smooth base. Note the folding and faulting of the sedimentary section above the salt. The reflection seismic method has been used to delineate near-surface geology for the purpose of coal and mineral exploration and engineering studies, especially in recent years with increasing acceptance. Figure I-2a shows a seismic section along a 500-m traverse across a bedrock valley with steep flanks. The lithologic column based on borehole data indicates a sedimentary sequence of clay, sand, and gravel deposited within the valley. The bedrock is approximately 15 m below the surface at the fringes of the valley and 65 m below the surface at the bottom of the valley. The strong reflection at the sediment-bedrock boundary is a result of the contrast between the low-velocity sediments above and the high-velocity Precambrian quartz pegmatite below. The reflection seismic method also has been used to delineate the crustal structure down to the Moho discontinuity and below. Figure I2b shows a seismic section recorded on land along a 15-km traverse. Based on regional control, it is known that the section consists of sediments down to about 4 km. The reflection event at 6.57 s, which corresponds to a depth range of 1520 km, can be postulated as the crystalline basement. The group of reflections between 810 s, which corresponds to a depth range of 2535 km, represents a transition zone in the lower crust most likely, the Moho discontinuity, itself. Common-midpoint (CMP) recording is the most widely used seismic data acquisition technique. By providing redundancy, measured as the fold of coverage in the seismic experiment, it improves signal quality. ![]() These two different vintages of data have been subjected to different treatments in processing; nevertheless, the fold of coverage has caused the most difference in the signal level of the final sections.
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