Seismic evidence for hotspot-induced buoyant flow beneath the Reykjanes Ridge

被引:53
作者
Gaherty, JB [1 ]
机构
[1] Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA
关键词
D O I
10.1126/science.1061565
中图分类号
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号
07 ; 0710 ; 09 ;
摘要
Volcanic hotspots and mid-ocean ridge spreading centers are the surface expressions of upwelling in Earth's mantle convection system, and their interaction provides unique information on upwelling dynamics. I investigated the influence of the Iceland hotspot on the adjacent mid-Atlantic spreading center using phase-delay times of seismic surface waves, which show anomalous polarization anisotropy-a delay-time discrepancy between waves with different polarizations. This anisotropy implies that the hotspot induces buoyancy-driven upwelling in the mantle beneath the ridge.
引用
收藏
页码:1645 / 1647
页数:3
相关论文
共 32 条
[1]   Buoyant mantle upwelling and crustal production at oceanic spreading centers: On-axis segmentation and off-axis melting [J].
BarnouinJha, K ;
Parmentier, EM ;
Sparks, DW .
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH, 1997, 102 (B6) :11979-11989
[2]   CRUSTAL CONTROL OF RIDGE SEGMENTATION INFERRED FROM OBSERVATIONS OF THE REYKJANES RIDGE [J].
BELL, RE ;
BUCK, WR .
NATURE, 1992, 357 (6379) :583-586
[3]   Teleseismic imaging of subaxial flow at mid-ocean ridges: Traveltime effects of anisotropic mineral texture in the mantle [J].
Blackman, DK ;
Kendall, JM ;
Dawson, PR ;
Wenk, HR ;
Boyce, D ;
Morgan, JP .
GEOPHYSICAL JOURNAL INTERNATIONAL, 1996, 127 (02) :415-426
[4]   The unique anisotropy of the Pacific upper mantle [J].
Ekström, G ;
Dziewonski, AM .
NATURE, 1998, 394 (6689) :168-172
[5]   Thermal and chemical structure of the Iceland plume [J].
Fitton, JG ;
Saunders, AD ;
Norry, MJ ;
Hardarson, BS ;
Taylor, RN .
EARTH AND PLANETARY SCIENCE LETTERS, 1997, 153 (3-4) :197-208
[6]   Seismic structure of the upper mantle in a central Pacific corridor [J].
Gaherty, JB ;
Jordan, TH ;
Gee, LS .
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH, 1996, 101 (B10) :22291-22309
[7]   GENERALIZED SEISMOLOGICAL DATA FUNCTIONALS [J].
GEE, LS ;
JORDAN, TH .
GEOPHYSICAL JOURNAL INTERNATIONAL, 1992, 111 (02) :363-390
[8]   Water in the oceanic upper mantle: Implications for rheology, melt extraction and the evolution of the lithosphere [J].
Hirth, G ;
Kohlstedt, DL .
EARTH AND PLANETARY SCIENCE LETTERS, 1996, 144 (1-2) :93-108
[9]   Mantle flow, melting, and dehydration of the Iceland mantle plume [J].
Ito, G ;
Shen, Y ;
Hirth, G ;
Wolfe, CJ .
EARTH AND PLANETARY SCIENCE LETTERS, 1999, 165 (01) :81-96
[10]   Reykjanes 'V'-shaped ridges originating from a pulsing and dehydrating mantle plume [J].
Ito, G .
NATURE, 2001, 411 (6838) :681-684