Volume 40 Issue 5
May  2021
Turn off MathJax
Article Contents
Caicai Zha, Jian Lin, Zhiyuan Zhou, Xubo Zhang, Min Xu, Fan Zhang. Variations in melt supply along an orthogonal supersegment of the Southwest Indian Ridge (16°–25°E)[J]. Acta Oceanologica Sinica, 2021, 40(5): 94-104. doi: 10.1007/s13131-021-1724-3
Citation: Caicai Zha, Jian Lin, Zhiyuan Zhou, Xubo Zhang, Min Xu, Fan Zhang. Variations in melt supply along an orthogonal supersegment of the Southwest Indian Ridge (16°–25°E)[J]. Acta Oceanologica Sinica, 2021, 40(5): 94-104. doi: 10.1007/s13131-021-1724-3

Variations in melt supply along an orthogonal supersegment of the Southwest Indian Ridge (16°–25°E)

doi: 10.1007/s13131-021-1724-3
Funds:  The Program of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) under contract No. GML2019ZD0205; the National Natural Science Foundation of China under contract Nos 41890813, 41976066, 41976064, 91858207, 91958211 and 91628301; the Program of Chinese Academy of Sciences under contract Nos Y4SL021001, QYZDY-SSW-DQC005 and 133244KYSB20180029; the National Key Research and Development Program of China under contract Nos 2018YFC0309800 and 2018YFC0310105; the Guangdong Basic and Applied Basic Research Foundation under contract No. 2021A1515012227; the Program of China Ocean Mineral Resources Research and Development Association under contract No. DY135-S2-1-04.
More Information
  • Corresponding author: E-mail: jlin@whoi.edu
  • Received Date: 2020-03-05
  • Accepted Date: 2020-05-03
  • Available Online: 2021-04-20
  • Publish Date: 2021-05-01
  • The orthogonal supersegment of the ultraslow-spreading Southwest Indian Ridge at 16°–25°E is characterized by significant along-axis variations of mantle potential temperature. A detailed analysis of multibeam bathymetry, gravity, and magnetic data were performed to investigate its variations in magma supply and crustal accretion process. The results revealed distinct across-axis variations of magma supply. Specifically, the regionally averaged crustal thickness reduced systematically from around 7 Ma to the present, indicating a regionally decreasing magma supply. The crustal structure is asymmetric in regional scale between the conjugate ridge flanks, with the faster-spreading southern flank showing thinner crust and greater degree of tectonic extension. Geodynamic models of mantle melting suggested that the observed variations in axial crustal thickness and major element geochemistry can be adequately explained by an eastward decrease in mantle potential temperature of about 40°C beneath the ridge axis. In this work, a synthesized model was proposed to explain the axial variations of magma supply and ridge segmentation stabilities. The existence of large ridge-axis offsets may play important roles in controlling melt supply. Several large ridge-axis offsets in the eastern section (21°–25°E) caused sustained along-axis focusing of magma supply at the centers of eastern ridge segments, enabling quasi-stable segmentation. In contrast, the western section (16°–21°E), which lacks large ridge-axis offsets, is associated with unstable segmentation patterns.
  • loading
  • [1]
    Behn M D, Grove T L. 2015. Melting systematics in mid-ocean ridge basalts: application of a plagioclase-spinel melting model to global variations in major element chemistry and crustal thickness. Journal of Geophysical Research: Solid Earth, 120(7): 4863–4886. doi: 10.1002/2015JB011885
    [2]
    Bernard A, Munschy M, Rotstein Y, et al. 2005. Refined spreading history at the Southwest Indian Ridge for the last 96 Ma, with the aid of satellite gravity data. Geophysical Journal International, 162(3): 765–778. doi: 10.1111/j.1365-246X.2005.02672.x
    [3]
    Canales J P, Detrick R S, Lin Jian, et al. 2000. Crustal and upper mantle seismic structure beneath the rift mountains and across a nontransform offset at the Mid-Atlantic Ridge (35°N). Journal of Geophysical Research: Solid Earth, 105(B2): 2699–2719. doi: 10.1029/1999JB900379
    [4]
    Cannat M, Rommevaux-Jestin C, Fujimoto H. 2003. Melt supply variations to a magma-poor ultra-slow spreading ridge (Southwest Indian Ridge 61° to 69°E). Geochemistry, Geophysics, Geosystems, 4(8): 9104. doi: 10.1029/2002GC000480
    [5]
    Carbotte S M, Smith D K, Cannat M, et al. 2015. Tectonic and magmatic segmentation of the Global Ocean Ridge System: a synthesis of observations. Geological Society of London, 420(1): 249–295. doi: 10.1144/SP420.5
    [6]
    Dalton C A, Langmuir C H, Gale A. 2014. Geophysical and geochemical evidence for deep temperature variations beneath mid-ocean ridges. Science, 344(6179): 80–83. doi: 10.1126/science.1249466
    [7]
    Dannowski A, Phipps Morgan J, Grevemeyer I, et al. 2018. Enhanced mantle upwelling/melting caused segment propagation, oceanic core complex die off, and the death of a transform fault: the Mid-Atlantic Ridge at 21.5°N. Journal of Geophysical Research: Solid Earth, 123(2): 941–956. doi: 10.1002/2017JB014273
    [8]
    DeMets C, Merkouriev S, Sauter D. 2015. High-resolution estimates of Southwest Indian Ridge plate motions, 20 Ma to present. Geophysical Journal International, 203(3): 1495–1527. doi: 10.1093/gji/ggv366
    [9]
    Dick H J B, Lin Jian, Schouten H. 2003. An ultraslow-spreading class of ocean ridge. Nature, 426(6965): 405–412. doi: 10.1038/nature02128
    [10]
    Escartín J, Cowie P A, Searle R C, et al. 1999. Quantifying tectonic strain and magmatic accretion at a slow spreading ridge segment, Mid-Atlantic Ridge, 29°N. Journal of Geophysical Research: Solid Earth, 104(B5): 10421–10437. doi: 10.1029/1998JB900097
    [11]
    Forsyth D W. 1993. Crustal thickness and the average depth and degree of melting in fractional melting models of passive flow beneath mid-ocean ridges. Journal of Geophysical Research: Solid Earth, 98(B9): 16073–16079. doi: 10.1029/93JB01722
    [12]
    Fox P J, Gallo D G. 1984. A tectonic model for ridge-transform-ridge plate boundaries: implications for the structure of oceanic lithosphere. Tectonophysics, 104(3–4): 205–242
    [13]
    Gente P, Pockalny R A, Durand C, et al. 1995. Characteristics and evolution of the segmentation of the Mid-Atlantic Ridge between 20°N and 24°N during the last 10 million years. Earth and Planetary Science Letters, 129(1–4): 55–71
    [14]
    Georgen J E, Lin Jian, Dick H J B. 2001. Evidence from gravity anomalies for interactions of the Marion and Bouvet hotspots with the Southwest Indian Ridge: effects of transform offsets. Earth and Planetary Science Letters, 187(3–4): 283–300
    [15]
    Gregg P M, Behn M D, Lin Jian, et al. 2009. Melt generation, crystallization, and extraction beneath segmented oceanic transform faults. Journal of Geophysical Research: Solid Earth, 114(B11): B11102
    [16]
    Grindlay N R, Madsen J A, Rommevaux-Jestin C, et al. 1998. A different pattern of ridge segmentation and mantle Bouguer gravity anomalies along the ultra-slow spreading Southwest Indian Ridge (15°30'E to 25°E). Earth and Planetary Science Letters, 161(1–4): 243–253
    [17]
    Hooft E E E, Detrick R S, Toomey D R, et al. 2000. Crustal thickness and structure along three contrasting spreading segments of the Mid-Atlantic Ridge, 33.5°–35°N. Journal of Geophysical Research: Solid Earth, 105(B4): 8205–8226. doi: 10.1029/1999JB900442
    [18]
    Hosford A, Lin Jian, Detrick R S. 2001. Crustal evolution over the last 2 m.y. at the Mid-Atlantic Ridge OH-1 segment, 35°N. Journal of Geophysical Research, 106(B7): 13269–13285. doi: 10.1029/2001JB000235
    [19]
    Kuo B Y, Forsyth D W. 1988. Gravity anomalies of the ridge-transform system in the South Atlantic between 31° and 34.5°S: upwelling centers and variations in crustal thickness. Marine Geophysical Researches, 10(3–4): 205–232
    [20]
    Lin Jian, Phipps Morgan J. 1992. The spreading rate dependence of three-dimensional mid-ocean ridge gravity structure. Geophysical Research Letters, 19(1): 13–16. doi: 10.1029/91GL03041
    [21]
    Lin Jian, Purdy G, Schouten H, et al. 1990. Evidence from gravity data for focusedmagmatic accretionalong the Mid-Atlantic Ridge. Nature, 344(6267): 627–632. doi: 10.1038/344627a0
    [22]
    Macdonald K C, Scheirer D S, Carbotte S M. 1991. Mid-ocean ridges: discontinuities, segments and giant cracks. Science, 253(5023): 986–994. doi: 10.1126/science.253.5023.986
    [23]
    Magde L S, Sparks D W. 1997. Three-dimensional mantle upwelling, melt generation, and melt migration beneath segment slow spreading ridges. Journal of Geophysical Research: Solid Earth, 1997(B9): 20571–20583
    [24]
    Müller R D, Sdrolias M, Gaina C, et al. 2008. Age, spreading rates, and spreading asymmetry of the world’s ocean crust. Geochemistry, Geophysics, Geosystems, 9(4): Q04006. doi: 10.1029/2007GC001743
    [25]
    Pariso J E, Sempéré J C, Rommevaux C. 1995. Temporal and spatial variations in crustal accretion along the Mid-Atlantic Ridge (29°–31°30′N) over the last 10 m.y.: implications from a three-dimensional gravity study. Journal of Geophysical Research: Solid Earth, 100(B9): 17781–17794. doi: 10.1029/95JB01146
    [26]
    Parker R L. 1973. The rapid calculation of potential anomalies. Geophysical Journal International, 31(4): 447–455. doi: 10.1111/j.1365-246X.1973.tb06513.x
    [27]
    Patriat P, Sauter D, Munschy M, et al. 1997. A survey of the Southwest Indian Ridge axis between Atlantis II fracture zone and the Indian Ocean triple junction: regional setting and large scale segmentation. Marine Geophysical Researches, 19(6): 457–480. doi: 10.1023/A:1004312623534
    [28]
    Phipps Morgan J, Forsyth D W. 1988. Three-dimensional flow and temperature perturbations due to a transform offset: effects on oceanic crustal and upper mantle structure. Journal of Geophysical Research: Solid Earth, 93(B4): 2955–2966. doi: 10.1029/JB093iB04p02955
    [29]
    Sandwell D T, Müller R D, Smith W H F, et al. 2014. New global marine gravity model from CryoSat-2 and Jason-1 reveals buried tectonic structure. Science, 346(6205): 65–67. doi: 10.1126/science.1258213
    [30]
    Sauter D, Patriat P, Rommevaux-Jestin C, et al. 2001. The Southwest Indian Ridge between 49°15′E and 57°E: focused accretion and magma redistribution. Earth and Planetary Science Letters, 192(3): 303–317. doi: 10.1016/S0012-821X(01)00455-1
    [31]
    Schouten H, Klitgord K D, Whitehead J A. 1985. Segmentation of mid-ocean ridges. Nature, 317(6034): 225–229. doi: 10.1038/317225a0
    [32]
    Sempéré J C, Lin Jian, Brown H S, et al. 1993. Segmentation and morphotectonic variations along a slow-spreading center: the Mid-Atlantic Ridge (24°00′N–30°40′N). Marine Geophysical Researches, 15(3): 153–200. doi: 10.1007/BF01204232
    [33]
    Sparks D W, Parmentier E M, Phipps Morgan J. 1993. Three-dimensional mantle convection beneath a segmented spreading center: implications for along-axis variations in crustal thickness and gravity. Journal of Geophysical Research: Solid Earth, 98(B12): 21977–21995. doi: 10.1029/93JB02397
    [34]
    Standish J J, Dick H J B, Michael P J, et al. 2008. MORB generation beneath the ultraslow spreading Southwest Indian Ridge (9°–25°E): major element chemistry and the importance of process versus source. Geochemistry, Geophysics, Geosystems, 9(5): Q05004. doi: 10.1029/2008GC001959
    [35]
    Tolstoy M, Harding A J, Orcutt J A. 1993. Crustal thickness on the Mid-Atlantic Ridge: bull’s-eye gravity anomalies and focused accretion. Science, 262(5134): 726–729. doi: 10.1126/science.262.5134.726
    [36]
    Tozer B, Sandwell D T, Smith W H F, et al. 2019. Global bathymetry and topography at 15 arc sec: SRTM15+. Earth and Space Science, 6: 1847–1864. doi: 10.1029/2019EA000658
    [37]
    Tucholke B E, Lin Jian, Kleinrock M C, et al. 1997. Segmentation and crustal structure of the western Mid-Atlantic Ridge flank, 25°25′–27°10′N and 0–29 m.y. Journal of Geophysical Research: Solid Earth, 102(B5): 10203–10223. doi: 10.1029/96JB03896
    [38]
    Wang T T, Tucholke B E, Lin Jian. 2015. Spatial and temporal variations in crustal production at the Mid-Atlantic Ridge, 25°N–27°30′N and 0–27 Ma. Journal of Geophysical Research: Solid Earth, 120(4): 2119–2142. doi: 10.1002/2014JB011501
    [39]
    Wessel P, Smith W H F. 1998. New, improved version of generic mapping tools released. Eos, Transactions American Geophysical Union, 79(47): 579. doi: 10.1029/98EO00426
    [40]
    Yang H J, Kinzler R J, Grove T L, et al. 1996. Experiments and models of anhydrous, basaltic olivine-plagioclase-augite saturated melts from 0.001 to 10 kbar. Contributions to Mineralogy and Petrology, 124(1): 1–18. doi: 10.1007/s004100050169
    [41]
    Zhang Fan, Lin Jian, Zhang Xubo, et al. 2018. Asymmetry in oceanic crustal structure of the South China Sea basin and its implications on mantle geodynamics. International Geology Review, 62(7–8): 840–858. doi: 10.1080/00206814.2018.1425922
    [42]
    Zhang Tao, Lin Jin, Gao Jinyao. 2019. Asymmetric crustal structure of the ultraslow-spreading Mohns Ridge. International Geology Review, 62(5): 568–584. doi: 10.1080/00206814.2019.1627586
    [43]
    Zheng Tingting, Tucholke B E, Lin Jian. 2019. Long-term evolution of nontransform discontinuities at the Mid-Atlantic Ridge, 24°N–27°30′N. Journal of Geophysical Research: Solid Earth, 124(10): 10023–10055. doi: 10.1029/2019JB017648
  • Supplementary information-Zhacaicai.pdf
  • 加载中

Catalog

    通讯作者: 陈斌, bchen63@163.com
    • 1. 

      沈阳化工大学材料科学与工程学院 沈阳 110142

    1. 本站搜索
    2. 百度学术搜索
    3. 万方数据库搜索
    4. CNKI搜索

    Figures(10)  / Tables(2)

    Article Metrics

    Article views (265) PDF downloads(37) Cited by()
    Proportional views
    Related

    /

    DownLoad:  Full-Size Img  PowerPoint
    Return
    Return