Three-dimensional tomographic / velocity structure of upper crust, CoAxial segment, Juan de Fuca Ridge: Implications for on-axis evolution and hydrothermal circulation

Journal of Geophysical Research: Solid Earth

Volumn 102, Issue B8, 1997, Pages 17679-17695

  Sohn, Robert A ^a   Webb, Spahr C ^a   Hildebrand, John A ^a   Cornuelle, Bruce D ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CRUSTAL EVOLUTION; HYDROTHERMAL CIRCULATION; HYDROTHERMAL FLOW; MID OCEAN RIDGE; MID-OCEAN RIDGES; SEISMIC TOMOGRAPHY; UPPER CRUST;

PACIFIC, JUAN DE FUCA RIDGE, COAXIAL SEGMENT;

EID: 0031423182     PISSN: 21699313     EISSN: 21699356     Source Type: Journal    
DOI: 10.1029/97jb00592     Document Type: Article

References (46)

1. Aki, K., and P. G. Richards, Quantitative Seismology Theory and Methods, W. H. Freeman, New York, 1980.
2. Burnett, M. S., The crustal structure of the East Pacific Rise near 12° 50'N: Results from the MAGMA seismic refraction experiment, Ph.D. dissertation, 375 pp. Univ. of Calif., San Diego, 1990.
3. Cann, J. R., and M. R. Strens, Modeling periodic megaplume emission by black smoker systems, J. Geophys. Res., 94, 12,227-12,237, 1989.
4. Carlson, R. L., and C. N. Herrick, Densities and porosities in the oceanic crust and their variations with depth and age, J. Geophys. Res., 95, 9153-9170, 1990.
5. Chadwick, W. W., R. W. Embley, and C. G. Fox, SeaBeam depth changes associated with recent lava flows, CoAxial segment, Juan de Fuca Ridge: Evidence for multiple eruptions between 1981-1993, Geophys. Res. Lett., 22, 167-170, 1995.
6. Chen, Y., and W. J. Morgan, Rift valley/no rift valley transition at mid-ocean ridges, J. Geophys. Res., 95, 17,571-17,581, 1990.
7. Christensen, N. I., Compressional wave velocities in basalts from the Juan de Fuca Ridge, J. Geophys. Res., 75, 2773-2775, 1970.
8. Christensen, N. I., Pore pressure and oceanic crustal seismic structure, Geophys. J. R. Astron. Soc., 79, 411-423, 1984.
9. Christeson, G. L., G.M. Purdy, and K. M. M. Rohr, Structure of the northern symmetrical segment of the Juan de Fuca Ridge, Mar. Geophys. Res., 15, 219-240, 1993.
10. Crampin, S., and D. Bamford, Inversion of P-wave velocity anisotropy, Geophys. J. R. Astron. Soc., 49, 123-132, 1977.
11. Crawford, W. C., Determination of oceanic crustal shear velocity structure from seafloor compliance measurements, Ph.D. dissertation, 93 pp. Univ. of Calif., San Diego, 1994.
12. Crawford, W. C., S. C. Webb, and J. A. Hildebrand, Seafloor compliance observed by long-period pressure and displacement measurements, J. Geophys. Res., 96, 16,151-16,160, 1991.
13. Creager, K. C., and L. M. Dorman, Location of instruments on the seafloor by joint adjustment of instrument and ship positions, J. Geophys. Res., 87, 8379-8387, 1982.
14. Cudrak, C. F., and R. M. Clowes, Crustal structure of Endeavour Ridge segment, Juan de Fuca Ridge, from a detailed seismic refraction survey, J. Geophys. Res., 98, 6329-6349, 1993.
15. Davis, E. E., and R. G. Currie, Geophysical observations of the northern Juan de Fuca Ridge system: Lessons in sea-floor spreading, Can. J. Earth Sci., 30, 278-300, 1992.
16. Delaney, J. R., H. P. Johnson, and J. L. Karsten, The Juan de Fuca ridge-hot spot-propagating rift system: New tectonic, geochemical, and magnetic data, J. Geophys. Res., 86, 11,747-11,750, 1981.
17. Delaney, J. R., M. D. Lilley, R. E. McDuff, D. S. Kelley, W. S. Wilcock, and V. Robigou, Cellular Hydrothermal Circulation in a Submarine System (abstract), Eos Trans. AGU, 77(46), Fall Meet. Suppl., 756, 1996.
18. Dushaw, B. D., P. F. Worcester, B. D. Cornuelle, and B. M. Howe, On equations for the speed of sound in sea water, J. Acoust. Soc. Am., 93, 255-275, 1993.
19. Dziak, R. P., C. G. Fox, and A. E. Schreiner, The June-July 1993 seismo-acoustic event at CoAxial segment, Juan de Fuca Ridge: Evidence for a lateral dike injection, Geophys. Res. Lett., 22, 135-138, 1995.
20. Embley, R. W., W. W. Chadwick, I. R. Jonasson, D. A. Butterfield, and E. T. Baker, Initial results of the rapid response to the 1993 CoAxial event: Relationships between hydrothermal and volcanic processes, Geophys. Res. Lett., 22, 143-146, 1995.
21. Fox, C. G., W. E. Radford, R. P. Dziak, T. Lau, H. Matsumoto, and A. E. Schreiner, Acoustic detection of a seafloor spreading episode on the Juan de Fuca Ridge using military hydrophone arrays, Geophys. Res. Lett., 22, 131-134, 1995.
22. Hammer, P. T. C., L. M. Dorman, J. A. Hildebrand, and B. D. Cornuelle, Jasper Seamount structure: Seafloor seismic refraction tomography, J. Geophys. Res., 99, 6731-6752, 1994.
23. Harding, A. J., G. M. Kent, and J. A. Orcutt, A multichannel seismic investigation of upper crustal structure at 9°N on the East Pacific Rise: Implications for crustal accretion, J. Geophys. Res., 98, 13,925-13,944, 1993.
24. Houtz, R., and J. Ewing, Upper crustal structure as a function of plate age, J. Geophys. Res., 81, 2490-2498, 1976.
25. Hudson, J. A., Wave speeds and attenuation of elastic waves in material containing cracks, Geophys. J. R. Astron. Soc., 64, 133-150, 1981.
26. Kent, G. M., A. J. Harding, and J. A. Orcutt, Distribution of magma beneath the East Pacific Rise between the Clipperton Transform and the 9°17'N Deval from forward modeling of common depth point data, J. Geophys. Res., 98, 13,945-13,969, 1993.
27. Kuster, G. T., and M. N. Toksoz, Velocity and attenuation of seismic waves in two phase media, 1, Theoretical formulations, Geophysics, 39, 587-606, 1974.
28. McDonald, M. A., S. C. Webb, J. A. Hildebrand, B. D. Cornuelle, and C. G. Fox, Seismic structure and anisotropy of the Juan de Fuca Ridge at 45N, J. Geophys. Res., 99, 4857-4873, 1994.
29. Mottl, M. J., et al., Warm springs discovered on 3.4 Ma-old crust, Baby Bare outcrop, eastern flank of the Juan de Fuca Ridge: Flank flux 95 (abstract), Eos Trans. AGU, 76(46), Fall Meet. Suppl., 419, 1995.
30. O'Connell, R. J., and B. Budiansky, Seismic velocities in dry and saturated cracked solids, J. Geophys. Res., 79, 5412-5426, 1974.
31. Raitt, R. W., The crustal rocks, The Sea, vol. 3, The Earth Beneath the Sea, edited by M. N. Hill, pp. 84-102, Wiley-Interscience, New York, 1963.
32. Sato, H., I. S. Sacks, and T. Murase, The use of laboratory velocity data for estimating temperature and partial melt fraction in the low-velocity zone: Comparison with heat flow and electrical conductivity studies, J. Geophys. Res., 94, 5689-5704, 1989.
33. Shearer, P. M., and J. A. Orcutt, Compressional and shear wave anisotropy in the oceanic lithosphere - The Ngendei seismic refraction experiment, Geophys. J. R. Astron. Soc., 87, 967-1003, 1986.
34. Shor, G. G., Jr., H. W. Menard, and R. W. Raitt, Structure of the Pacific basin, The Sea, vol. 4, edited by Maxwell, A. E., pp. 3-27, Wiley-Interscience, New York, 1971.
35. Small, C., and D. T. Sandwell, An abrupt change in ridge axis gravity with spreading rate, J. Geophys. Res., 94, 17,383-17,392, 1989.
36. Sohn, R. A., Oceanic spreading center accretionary process studies with ocean bottom seismometers, Ph.D. dissertation, 74 pp., Univ. of Calif., San Diego, 1996.
37. Spiess, F. N., and J. A. Hildebrand, Deep tow studies of recent activity on the Juan de Fuca Ridge (abstract), Eos Trans. AGU, 74(43), Fall Meet. Suppl., 620, 1993.
38. van Everdingen, D. A., Fracture characteristics of the sheeted dike complex, Troodos ophiolite, Cyprus: Implications for permeability of oceanic crust, J. Geophys. Res., 100, 19,957-19,972, 1995.
39. Wheat, C. G., M. J. Mottl, E. E. Davis, and E. T. Baker, Mass, thermal, and chemical fluxes from a ridge flank hydrothermal system: Flank flux (FF 92-95), Eos Trans. AGU, 76(46), Fall Meet. Suppl., 419, 1995.
40. White, D. J., and R. M. Clowes, Shallow crustal structure beneath the Juan de Fuca Ridge from 2-D seismic refraction tomography, Geophys. J. Int., 100, 349-367, 1990.
41. White, D. J., and R. M. Clowes, Seismic attenuation structure beneath the Juan de Fuca Ridge from tomographic inversion of amplitudes, J. Geophys. Res., 99, 3043-3056, 1994.
42. Wiggins, S. M., L. M. Dorman, B. D. Cornuelle, and J. A. Hildebrand, Hess Deep rift valley structure from seismic tomography, J. Geophys. Res., 101, 22,335-22,353, 1996.
43. Wilcock, W. S. D., S. C. Solomon, G. M. Purdy, and D. R. Toomey, Seismic attenuation structure of the East Pacific Rise near 9°30'N, J. Geophys. Res., 100, 24147-24165, 1995.
44. Wilkens, R. H., G. J. Fryer, and J. Karsten, Evolution of porosity and seismic structure of upper oceanic crust: Importance of aspect ratios, J. Geophys. Res., 96, 17,981-17,995, 1991.
45. Wright, D. J., R. M. Haymon, and K. C. MacDonald, Breaking new ground: Estimates of crack depth along the axial zone of the East Pacific Rise (9°12'-54'N), Earth Planet. Sci. Lett., 134, 441-457, 1995.
46. Yang, J., R. N. Edwards, J. W. Molson, and E. A. Sudicky, Fracture-induced hydrothermal convection in the oceanic crust and the interpretation of heat-flow data, Geophys. Res. Lett., 23, 929-932, 1996.