The Journal of the Petrological Society of Korea (암석학회지)

The Petrological Society of Korea (한국암석학회)
권호 표지

New Approach on the Extinction of Spreading at the Phoenix Ridge, Antarctica

남극 피닉스 해령 확장작용 소멸시기에 대한 새로운 고찰

  • 최원희 (한국해양연구원 부설 극지연구소) ;
  • 이종익 (한국해양연구원 부설 극지연구소) ;
  • 이미정 (한국해양연구원 부설 극지연구소) ;
  • 허순도 (한국해양연구원 부설 극지연구소) ;
  • 진영근 (한국해양연구원 부설 극지연구소)
  • Published : 2005.03.01
Download PDF
⟨ Previous Next ⟩

Abstract

K-Ar ages have been determined for the submarine basalts dredged from the P2 and P3 segments of the Phoenix Ridge, Drake Passage, Antarctica, for better understanding on the extinction of seafloor spreading. At the P3 segment, the K-Ar ages of the rifted ridge basalts are 3.5-6.4 Ma, and those for the axial seamount basalts are 1.5-3.1 Ma. The K-Ar ages for the basalts at the rifted ridge and axial central high in the P2 segment are 2.1 and 1.4-1.9 Ma, respectively. We suggest that the extinction of seafloor spreading at the P3 and P2 segments occurred at 3.3 and 2.0 Ma, respectively, on the basis of ridge structure and formation time of basalts. This result favors a stepwise extinction model rather than a simultaneous one on the extinction of the Phoenix Ridge.

남극 드레이크 해협에서 작은 해양판으로 존재하는 피닉스판의 확장 작용 소멸 시기를 보다 명확하게 이해하고자 해령의 각 구역에서 체계적으로 채취된 현무암편을 대상으로 K-Ar 연대 측정을 실시하였다. 남서쪽 P3 구역 열극 사면 현무암의 K-Ar 연령은 3.5-6.4Ma이고 해령 축부 거대 화산체의 연령은 1.5-3.1Ma이다. 중앙의 P2 구역 열극 사면 현무암의 연령은 2.1 Ma이고, 축부 중앙고지대 현무암의 연령은 1.4-1.9Ma이다. 해령 축으로부터의 거리와 지체구조 특성에 기초한 확장작용 소멸시기는 P3 구역이 3.3Ma, P2 구역이 2.0Ma로 해석된다. 이 결과는 기존의 여러 지구물리 자료가 제시하는 '3.3Ma 동시 소멸설'과는 배치되며 해령의 P3 구역에서 P2 구역을 향해 확장작용이 단계적으로 소멸되었다는 것을 지지한다.

Keywords

References

  1. 김정민, 2001, 한국기초과학지원연구원에 도입된 K-Ar 연대 측정 시스템: 개요 및 성능. 암석학회지, 10, 172-178
  2. 이종익, 허순도, 이미정, 김규중, Keisuke Nagao, 2003, 남극 드레이크 해협 피닉스 해령 P3 구역 축부 해저현무암: K-Ar 연대측정과 지구화학. Ocean and Polar Research, 25, 107-118 https://doi.org/10.4217/OPR.2003.25.1.107
  3. Barker, D.H.N. and Austin, J.A., 1998, Rift propagation, detachment faulting, and associated magmatism in Bransfield Strait, Antarctic Peninsula. J. Geophys. Res., 103, 24017-24043 https://doi.org/10.1029/98JB01117
  4. Barker, P.F., 1982, The Cenozoic subduction history of the Pacific margin of the Antarctic Peninsula: ridge cresttrench interactions. J. Geol. Soc. London, 139, 787-801 https://doi.org/10.1144/gsjgs.139.6.0787
  5. Cande, S.C. and Leslie, R.B., 1986, Late Cenozoic tectonics of the Southern Chile Trench. J. Geophys. Res., 91, 471-496 https://doi.org/10.1029/JB091iB01p00471
  6. Cande, S.C., Leslie, R.B., Parra, J.C. and Hobart, M., 1987, Interaction between the Chile Ridge and Chile Trench: Geophysical and geothermal evidence. J. Geophys. Res., 92, 495-520 https://doi.org/10.1029/JB092iB01p00495
  7. Delaney, J.R., Johnson, H.P. and Karsten, J.L., 1981, The Juan de Fuca ridge-hotspot-propagating rift system: New tectonic, geochemical, and magnetic data. J. Geophys. Res., 86, 11747-11750 https://doi.org/10.1029/JB086iB12p11747
  8. Desonie, D.L. and Duncan, R.A., 1990, The Cobb-Eickelberg seamount chain: Hotspot volcanism with mid-ocean ridge basalt affinity. J. Geophys. Res., 95, 12697-12711 https://doi.org/10.1029/JB095iB08p12697
  9. Douglass, J., Schilling, J.-G. and Fontignie, D., 1999, Plume-ridge interactions of the Discovery and Shona mantle plumes with the southern mid-Atlantic Ridge $(40-55^{\circ}S)$. J. Geophys. Res., 104, 2941-2962 https://doi.org/10.1029/98JB02642
  10. Forsthe, R.D. and Nelson, E.P., 1985, Geological manifestations of ridge collision: Evidence from the Golfo de Penas-Taitao Basin, southern Chile. Tectonics, 4, 477-495 https://doi.org/10.1029/TC004i005p00477
  11. Forsthe, R.D., Nelson, E.P., Carr, M.J., Kaeding, M.E., Herve, F., Mpodozis, C., Soffia, J.M. and Harambour, S., 1986, Pliocene near trench magmatism in southern Chile: A possible manifestation of ridge collision. Geology, 14, 23-27 https://doi.org/10.1130/0091-7613(1986)14<23:PNMISC>2.0.CO;2
  12. Hebert, H., Villemant, B., Deplus, C. and Diament, M., 1999, Contrasting geophysical and geochemical signatures of a volcano at the axis of the Wharton fossil ridge (NE Indian Ocean). Geophys. Res. Lett., 26, 1053-1056 https://doi.org/10.1029/1999GL900160
  13. Kaneoka, I., 1993, Noble gas signatures of magmatic sources and processes. Geochem. J., 27, 201-211 https://doi.org/10.2343/geochemj.27.201
  14. Kim, K.J., 2005, Geophysical investigations of the Phoenix Ridge, a fossil spreading center in Drake Passage, Antarctica. Ph.D. dissertation, Seoul National University,156p
  15. Kruz, M.D., Le Roex, A. and Dick, H.J.B., 1998, Isotope geochemistry of the oceanic mantle near the Bouvet triple junction. Geochim. Cosmochim. Acta, 62, 841-852 https://doi.org/10.1016/S0016-7037(97)00383-9
  16. Larter, R.D. and Barker, P.F., 1991, Effects of ridge-trench interaction on Antarctic-Phoenix spreading: Forces on a young subducting plate. J. Geophys. Res., 96, 19583-19607
  17. Livermore, R., Balanya, J.C., Maldonado, A., Martinez, J.M., Rodriguez-Fernandez, J., Galdeano, C.S., Zaldivar, J.G., Jabaloy, A., Barnolas, A., Somoza, L., Hernandez-Molina, J., Surinach, E. and Viseras, C., 2000, Autopsy on a dead spreading center: The Phoenix Ridge, Drake Passage, Antarctica. Geology, 28, 607-610
  18. Macdonald, K.C., 1982, Mid-ocean ridges: Fine scale tectonic volcanic and hydrothermal processes within the plate boundary zone. Ann. Rev. Earth Planet. Sci., 10, 155-190 https://doi.org/10.1146/annurev.ea.10.050182.001103
  19. Maldonado, A., Larter, R.D. and Aldaya, F., 1994, Fore-arc tectonic evolutions of the South Shetland margin, Antarctic Peninsula. Tectonics, 13, 1345-1370 https://doi.org/10.1029/94TC01352
  20. Rhodes, J.M., Morgan, C. and Liias, R.A., 1990, Geochemistry of axial seamount lavas: Magmatic relationship between the Cobb hotspot and the Juan de Fuca Ridge. J. Geophys. Res., 95, 12713-12733 https://doi.org/10.1029/JB095iB08p12713
  21. Smith, W. H. F. and Sandwell, D. T., 1994, Bathymetric prediction from dense satellite altimetry and sparse shipboard bathymetry, J. Geophys. Res., 99, 21803-21824 https://doi.org/10.1029/94JB00988
  22. Steiger, R.H. and Jager, E., 1977, Subcommission on geochronology convension on the use of decay constants in geo- and cosmo-chronology. Earth Planet. Sci. Lett., 36, 359-362 https://doi.org/10.1016/0012-821X(77)90060-7
  23. Sudo, M., Uto, K., Anno, K., Ishizuka, O. and Uchiumi, S., 1998, SORI93 biotite: A New Mineral Standard for K-Ar Dating. Geochem. J., 32, 49-58 https://doi.org/10.2343/geochemj.32.49
  24. Tucholke, B.E. and Houtz, R.E., 1976, Sedimentary framework of the Bellingshausen Basin from seismic profiler data. Initial Report of Deep Sea Drilling Project, 35, 197-227