IS THE VOLCANIC ERUPTION HIGH THE PRODUCT OF HOTSPOT AND MID-OCEAN RIDGE INTERACTION?
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摘要: 观察西南印度洋脊(SWIR)27洋段(据Cannat等(1999)洋脊分段及命名)高分辨率多波束资料,发现其50.5°E轴部为一火山喷发高地,总体地形特征似乎类似受热点影响的洋脊。对该段洋脊地形作了详细分析,并结合受热点影响洋脊具有的一般特征,从地形地貌、地球物理场、岩石地球化学等方面分析了该段洋脊受热点影响的可能性。地形上缺少轴外地形表达,两翼也没有不对称现象;岩石地球化学上最普遍分布的仍是正常MORB。再者,在Crozet热点的相对运动历史轨迹上没有留下明显的痕迹,因此,其对相关洋脊产生有效影响的可能性并不大。综合SWIR 27洋段各方面特征,可说明其确实受某种因素影响,导致岩浆通量相比邻近洋段有大幅增加,但这种因素可能不是受热点影响,而是与大西洋中脊(MAR)上三段轴部地形异常的洋脊一样,是产生于由不均一地幔导致的洋脊局部岩浆增加。Abstract: It is found from the high-resolution multibeam data of Segment 27 (Cannat et al. 1999) on the Southwest Indian Ridge (SWIR) that there is an unexpected volcanic eruption high along the axis at 50.5 E, which is somewhat similar to the ridges effected by hotspots. We compared the high with the general characteristics of hotspot-effected mid-ocean ridges, made detailed topographic analysis and studied the topography, geophysical field and geochemical characteristics of the high in order to define whether the Segment 27 is effected by any hotspot nearby. Generally speaking, although there is some sort of similarities to the hotspot-effected ridge, it is not typical. Topographically, there is no off-axis topographical anomaly or asymmetric flanks, and geochemically, the most commonly distributed rocks are still normal basalts. Furthermore, there is actually no obvious record in the historical track of the Crozet hotspot showing any efficacious impact on SWIR. In this regard, we concluded that the Segment 27 was indeed effected by something which led to a substantial increase in magmatic flux, but most probably not the interaction with Crozet hotspot. A more reasonable interpretation is that this unexpected volcanic eruption high was resulted from a robust magmatism caused by local heterogeneity of mantle, just as the three similar ridge segments of MAR (Middle Atlantic Ridge) mentioned in literatures.
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Key words:
- ridge-hotspot /
- topography /
- geophysical field /
- geochemistry /
- SWIR
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[1] Wilson J T. A possible origin of the Hawaiian Islands[J]. Canadian Journal of Physics, 1963, 41(6):863-870.
[2] Morgan W J. Convection plumes in the lower mantle[J]. Nature, 1971, 230:42-43.
[3] 王登红. 地幔柱的概念、分类、演化与大规模成矿——对中国西南部的探讨[J]. 地学前缘, 2001, 8(3):67-72.
[WANG Denghong. Basic concept, classification, evolution of mantle plume and large scale mineralization probe into southwestern China[J]. Earth Science Frontiers, 2001, 8(3):67-72.]
[4] 鄢全树, 石学法. 洋中脊与地幔柱热点相互作用研究进展[J]. 海洋地质与第四纪地质, 2006, 26(5):131-138.
[YAN Quanshu, SHI Xuefa. Mantle plume(hotspot)ridge interaction[J]. Marine Geology and Quaternary Geology, 2006, 26(5):131-138.]
[5] Dyment J, Lin J, Baker E T. Ridge-hotspot interactions:what mid-ocean ridges tell us about deep Earth processe[J]. Oceanography 2007, 20(1):102-115.
[6] Schilling J G. Upper mantle heterogeneities and dynamics[J]. Nature, 1985, 314:62-67.
[7] Gente P, Dyment J, Maia M, et al. Interaction between the Mid-Atlantic Ridge and the Azores hot spot during the last 85 Myr:Emplacement and rifting of the hot spot-derived plateaus[J]. Geochemistry, Geophysics, Geosystems, 2003, 4(10):105-112.
[8] Maia M, Ackermand D, Dehghani G A, et al. The Pacific-Antarctic Ridge Foundation hotspot interaction:a case study of a ridge approaching a hotspot[J]. Marine Geology, 2000, 167(1):61-84.
[9] Georgen J E, Lin J. Plume-transform interactions at ultra-slow spreading ridges:Implications for the Southwest Indian Ridge[J]. Geochemistry, Geophysics, Geosystems, 2003, 4(9):87-92.
[10] Maia M, Pessanha I, Courr ges E, et al. Building of the Amsterdam-Saint Paul plateau:A 10 Myr history of a ridge-hot spot interaction and variations in the strength of the hot spot source[J]. Journal of Geophysical Research, 2011, 116(B9).
[11] Kincaid C, Schilling J G, Gable C. The dynamics of off-axis plume-ridge interaction in the uppermost mantle[J]. Earth and planetary science letters, 1996, 137(1):29-43.
[12] Sauter D, Cannat M, Meyzen C, et al. Propagation of a melting anomaly along the ultraslow Southwest Indian Ridge between 46°E and 52°20'E:interaction with the Crozet hotspot?[J]. Geophysical Journal International, 2009, 179(2):687-699.
[13] Behn M D, Sinton J M, Detrick R S. Effect of the Galápagos hotspot on seafloor volcanism along the Galápagos Spreading Center (90.9°~97.6°W)[J]. Earth and Planetary Science Letters, 2004, 217(3-4):331-347.
[14] Dick H J B, Lin J, Schouten H. An ultraslow-spreading class of ocean ridge[J]. Nature, 2003, 426(6965):405-412.
[15] Sauter D, Cannat M, Roum jon S, et al. Continuous exhumation of mantle-derived rocks at the Southwest Indian Ridge for 11 million years[J]. Nature Geoscience, 2013, 6(4):314-320.
[16] Georgen J E, Lin J, Dick H J B. Evidence from gravity anomalies for interactions of the Marion and Bouvet hotspots with the Southwest Indian Ridge:effects of transform offsets[J]. Earth and Planetary Science Letters, 2001, 187(3):283-300.
[17] Zhang Tao, Lin Jian, Gao Jinyao. Magmatism and tectonic processes in Area A hydrothermal vent on the Southwest Indian Ridge[J]. Science China Earth Sciences, 2013, 56(12):2186-2197.
[18] Cannat M, Rommevaux-Jestin C, Sauter D, et al. Formation of the axial relief at the very slow spreading Southwest Indian Ridge (49° to 69°E)[J]. Journal of Geophysical Research, 1999, 104(B10):22825.
[19] Liang Yuyang, Li Jiabiao, Li Shoujun, et al. The morphotectonics and its evolutionary dynamics of the central Southwest Indian Ridge (49° to 51°E)[J]. Acta Oceanologica Sinica, 2013, 32(12):87-95.
[20] Jacoby W, Gudmundsson M T. Hotspot Iceland:An introduction[J]. Journal of Geodynamics, 2007, 43(1):1-5.
[21] Riedel C, Ebbing J. Hotspot ridge interaction and its influence on Icelandic crust formation and dynamics[J]. Tectonophysics, 2008, 447(1):1-4.
[22] Morgan W J. Rodriguez, Darwin, Amsterdam,..., a second type of hotspot island[J]. Journal of Geophysical Research:Solid Earth, 1978, 83(B11):5355-5360.
[23] Small C. Observations of ridge-hotspot interactions in the Southern Ocean[J]. Journal of Geophysical Research:Solid Earth, 1995, 100(B5):17931-17946.
[24] Mittelstaedt E, Ito G. Plume-ridge interaction, lithospheric stresses, and the origin of near-ridge volcanic lineaments[J]. Geochemistry, Geophysics, Geosystems, 2005, 6(6):121-130.
[25] Grevemeyer I. Hotspot-ridge interaction in the Indian Ocean:constraints from Geosat/ERM altimetry[J]. Geophysical Journal International, 1996, 126(3):796-804.
[26] Leroy S, d'Acremont E, Tiberi C, et al. Recent off-axis volcanism in the eastern Gulf of Aden:Implications for plume ridge interaction[J]. Earth and Planetary Science Letters, 2010, 293(1-2):140-153.
[27] Ito G, Lin J, Graham D. Observational and theoretical studies of the dynamics of mantle plume mid-ocean ridge interaction[J]. Reviews of Geophysics, 2003, 41(4):135-142.
[28] Füri E, Hilton D R, Murton B J, et al. Helium isotope variations between R union Island and the Central Indian Ridge (17°~21°S):New evidence for ridge hot spot interaction[J]. Journal of Geophysical Research, 2011, 116(B2).
[29] Breton T, Nauret F, Pichat S, et al. Geochemical heterogeneities within the Crozet hotspot[J]. Earth and Planetary Science Letters, 2013, 376:126-136.
[30] Montelli R, Nolet G, Dahlen F A, et al. Finite-frequency tomography reveals a variety of plumes in the mantle[J]. Science, 2004, 303(5656):338-343.
[31] Montelli R, Nolet G, Dahlen F A, et al. A catalogue of deep mantle plumes:New results from finite-frequency tomography[J]. Geochemistry, Geophysics, Geosystems, 2006, 7(11):133-142.
[32] Van Der Hilst R D, Maarten V. Banana-doughnut kernels and mantle tomography[J]. Geophysical Journal International, 2005, 163(3):956-961.
[33] Kokfelt T F, Lundstrom C, Hoernle K, et al. Plume-ridge interaction studied at the Gal pagos spreading center:Evidence from 226Ra-230Th-238U and 231Pa-235U isotopic disequilibria[J]. Earth and Planetary Science Letters, 2005, 234(1-2):165-187.
[34] Zhang Tao, Lin Jian, Gao Jinyao. Interactions between hotspots and the Southwest Indian Ridge during the last 90 Ma:Implications on the formation of oceanic plateaus and intra-plate seamounts[J]. Science China Earth Sciences, 2011, 54(8):1177-1188.
[35] Foulger G R. The"plate"model for the genesis of melting anomalies[J]. Special Papers-Geological Society of America, 2007, 430(1):85-92.
[36] Sauter D, Patriat P, Rommevaux-Jestin C, et al. The Southwest Indian Ridge between 49°15'E and 57°E:focused accretion and magma redistribution[J]. Earth and Planetary Science Letters, 2001, 192(3):303-317.
[37] Hoernle K, Hauff F, Kokfelt T F, et al. On-and off-axis chemical heterogeneities along the South Atlantic Mid-Ocean-Ridge (5°~11°S):Shallow or deep recycling of ocean crust and/or intraplate volcanism?[J]. Earth and Planetary Science Letters, 2011, 306(1):86-97.
[38] Paulick H, M nker C, Schuth S. The influence of small-scale mantle heterogeneities on Mid-Ocean Ridge volcanism:Evidence from the southern Mid-Atlantic Ridge (7°30'S to 11°30'S) and Ascension Island[J]. Earth and Planetary Science Letters, 2010, 296(3):299-310.
[39] Bruguier N J, Minshull T A, Brozena J M. Morphology and tectonics of the Mid-Atlantic Ridge, 7°~12°S[J]. Journal of Geophysical Research, 2003, 108(B2).
[40] Regelous M, Niu Y, Abouchami W, et al. Shallow origin for South Atlantic Dupal Anomaly from lower continental crust:Geochemical evidence from the Mid-Atlantic Ridge at 26°S[J]. Lithos, 2009, 112(1):57-72.
[41] Niu Y, Bideau D, H kinian R, et al. Mantle compositional control on the extent of mantle melting, crust production, gravity anomaly, ridge morphology, and ridge segmentation A case study at the Mid-Atlantic Ridge 33°~35°N[J]. Earth and Planetary Science Letters, 2001, 186(3):383-399.
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