Kent, Graham M. et al. (1997): Evidence from Hole 504B for the origin of dipping events in oceanic crustal reflection profiles as out-of-plane scattering from basement topography

Leg/Site/Hole:
ODP 111
ODP 137
ODP 140
ODP 148
DSDP 69
DSDP 70
DSDP 83
DSDP 92
DSDP 69 504
DSDP 70 504
DSDP 83 504
DSDP 92 504
ODP 111 504
ODP 137 504
ODP 140 504
ODP 148 504
Identifier:
1997-020217
georefid

10.1130/0091-7613(1997)025<0131:EFHFTO>2.3.CO;2
doi

Creator:
Kent, Graham M.
Woods Hole Oceanographic Institution, Woods Hole, MA, United States
author

Detrick, Robert S.
Scripps Institution of Oceanography, La Jolla, CA, United States
author

Swift, Stephen A.
author

Collins, John A.
author

Kim, Isaac I.
author

Identification:
Evidence from Hole 504B for the origin of dipping events in oceanic crustal reflection profiles as out-of-plane scattering from basement topography
1997
Geology (Boulder)
Geological Society of America (GSA), Boulder, CO, United States
25
2
131-134
Dipping reflectors in oceanic crustal seismic reflection profiles have been attributed to either faults cutting through the crustal section or magmatic layering in the mid- to lower crust. Using closely spaced (<1 km) single-channel seismic and multichannel seismic profiles collected near Ocean Drilling Program Hole 504B, we show that a conspicuous dipping event previously interpreted as a low-angle fault striking perpendicular to the ridge axis is actually a scattering artifact from an approximately 80-m-high, sediment-buried basement fault scarp located approximately 2 km south of Hole 504B. The interplay between the orientation of the profile relative to basement topography and the streamer feathering angle can significantly increase the moveout of scattered energy above the sediment-basement root-mean-square velocity, allowing these scattered events to stack coherently at crustal velocities. These results suggest that in many cases dipping events imaged in oceanic crustal reflection profiles may be scattering artifacts rather than real geologic features.
English
Serial
Coverage:Geographic coordinates:
North:1.1600
West:-83.5000East: -83.3500
South:1.0900

Solid-earth geophysics; Applied geophysics; Oceanography; basement; bottom features; crust; Deep Sea Drilling Project; dip; DSDP Site 504; East Pacific; Equatorial Pacific; fault scarps; geophysical methods; geophysical profiles; geophysical surveys; IPOD; Leg 111; Leg 137; Leg 140; Leg 148; Leg 69; Leg 70; Leg 83; Leg 92; Ocean Drilling Program; ocean floors; oceanic crust; Pacific Ocean; reflection; seismic methods; seismic profiles; streamers; surveys; vertical seismic profiles; wave dispersion;

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