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Brocher & Hart 1991
Brocher, T.M. and Hart, P.E. (1991). Comparison of vibroseis and explosive source methods for deep crustal seismic reflection profiling in the basin and range province. Journal of Geophysical Research 96: doi: 10.1029/91JB01656. issn: 0148-0227.

Direct comparison of low-fold, high-energy explosive and high-fold, lower-energy vibroseis method for acquiring deep crustal seismic reflection data in the Basin and Range Province suggests that the high-fold common mid-point (CMP) method there does not provide the best possible image of lower crustal structure. During the recent acquisition of a Vibroseis profile in the Basin and Range Province we fired single deep shot holes to obtain a coincident single-fold explosive section. Within the upper crust (upper 3 s) the explosive source and Vibroseis records are nearly equivalent. For record times below 3 s, however, comparison of the explosive source gathers and the coincident final 60-fold Vibroseis section demonstrates that low-fold explosive profiling provides a higher-qualtiy image of the midcrust to lower crust (3-10 s). The higher record quality of the explosive sources results results primarily from the large seismic energy levels produced by the explosives, making them less sensitive to common noise sources. Whereas deeper than 4--5 s the Vibroseis energy levels on individual source effors fall to that of ambient noise levels, the explosions provide signal-generated energy exceeding ambient noise levels down to 18--19 s. Although individual reflections can be correlated on explosion and Vibroseis shot gathers, reflection events on the 60-fold Vibroseis stack do not correlate to those on the single-fold explosion profile, suggesting that the high-fold CMP method in our study did not maintain the integrity of the weak lower crustal reflected arrivals. Reasons why the high-fold CMP method apparently failed included complex, even time-varying, statics, nonhyperbolic moveout at long offsets, and the difficulty in resolving stacking velocities with data having low signal-to-noise ratios. Reflection on the explosion section are longer and imply a greater degree of layering than one would infer from the lower-energy Vibroseis section. ¿American Geophysical Union 1991

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Abstract

Keywords
Seismology, Continental crust, Exploration Geophysics, Seismic methods, Seismology, Instruments and techniques
Journal
Journal of Geophysical Research
http://www.agu.org/journals/jb/
Publisher
American Geophysical Union
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