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    Major Hotspots and Hotspot Tracks On Earth: Iceland Reunion Galapagos Louisville

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    Miguel Angel Catunta Zarate
    Major hotspots and hotspot tracks on Earth include Iceland, Reunion, Louisville, Galapagos, Hawaiian-Emperor Chain, Walvis Ridge, and Ninetyeast Ridge. Hotspots form age-progressive volcanic island and seamount chains as tectonic plates move over relatively fixed mantle plumes, producing "plume heads" like large igneous provinces and "plume tails" like hotspot tracks. The longest continuously recorded hotspot track is the Hawaiian-Emperor Chain. Mantle plumes are thought to transport heat and chemically distinct material from deep in the Earth to the surface, contributing to the formation of ocean islands and volcanic provinces.

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    Major Hotspots and Hotspot Tracks On Earth: Iceland Reunion Galapagos Louisville

    Uploaded by

    Miguel Angel Catunta Zarate
    30 views36 pages
    Major hotspots and hotspot tracks on Earth include Iceland, Reunion, Louisville, Galapagos, Hawaiian-Emperor Chain, Walvis Ridge, and Ninetyeast Ridge. Hotspots form age-progressive volcanic island and seamount chains as tectonic plates move over relatively fixed mantle plumes, producing "plume heads" like large igneous provinces and "plume tails" like hotspot tracks. The longest continuously recorded hotspot track is the Hawaiian-Emperor Chain. Mantle plumes are thought to transport heat and chemically distinct material from deep in the Earth to the surface, contributing to the formation of ocean islands and volcanic provinces.

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    Major hotspots and hotspot tracks on Earth include Iceland, Reunion, Louisville, Galapagos, Hawaiian-Emperor Chain, Walvis Ridge, and Ninetyeast Ridge. Hotspots form age-progressive volcanic island and seamount chains as tectonic plates move over relatively fixed mantle plumes, producing "plume heads" like large igneous provinces and "plume tails" like hotspot tracks. The longest continuously recorded hotspot track is the Hawaiian-Emperor Chain. Mantle plumes are thought to transport heat and chemically distinct material from deep in the Earth to the surface, contributing to the formation of ocean islands and volcanic provinces.

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    30 views36 pages

    Major Hotspots and Hotspot Tracks On Earth: Iceland Reunion Galapagos Louisville

    Uploaded by

    Miguel Angel Catunta Zarate
    Major hotspots and hotspot tracks on Earth include Iceland, Reunion, Louisville, Galapagos, Hawaiian-Emperor Chain, Walvis Ridge, and Ninetyeast Ridge. Hotspots form age-progressive volcanic island and seamount chains as tectonic plates move over relatively fixed mantle plumes, producing "plume heads" like large igneous provinces and "plume tails" like hotspot tracks. The longest continuously recorded hotspot track is the Hawaiian-Emperor Chain. Mantle plumes are thought to transport heat and chemically distinct material from deep in the Earth to the surface, contributing to the formation of ocean islands and volcanic provinces.

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    Major hotspots and hotspot tracks on Earth

    Iceland
    Reunion Louisville Galapagos

    Hawaiian-Emperor Chain Walvis Ridge


    Ninetyeast Ridge
    adapted from Coffin et al. (2006)
    *Goodliffe & Martinez (1997)
    Mahoney J. J. & Coffin M. F. (eds.) (1997)
    Plateaus & Hotspots: Heads vs.Tails

    Duncan and Richards, 1991

    “plume heads” = flood basalt provinces (continental or oceanic)


    “plume tails” = hotspot tracks (seamounts, oceanic islands)
    Longest Available Record

      Continuous:
    Hawaii
      Discontinuous:
    Cook-Austral
    continue in W
    Pacific assuming
    Absolute Plate
    Motion Model
    (APM)
    Mantle Convection, Mantle Plumes,
    LIPs & OIB A buoyant plume is characterized
    by a mushroom-shaped head and a
    thin, long stem.

    Upon impinging under a moving


    lithosphere, such a mantle
    upwelling will produce a massive
    “head” event, followed by smaller
    but long-lived “tail” events.

    Hotspot tracks are produced by


    impinging of the plume stem, while
    traps (CFB, oceanic plateaus)
    correspond to the plume head.

    Mantle plumes transport heat from the core to the surface and physically incorporate
    “enriched” portions of the mantle from the slab graveyard in the lower mantle.
    Fig 1.2
    Origin Of Volcanic Chains:
    Hotspots
      Form chains
      Age progressive
      Large seamounts
    or islands
      Chemically
    distinct from
    crust
      Plume origin…?
    Cracking as Alternative

      Cracks from regional extension and localized


    weaknesses
      Cracks from plate cooling
      Related extension causes passive upwelling, melting
    and volcanism
    Sr-Nd isotopic compositions

    MORB only
    Hawaii

    OIB only

    The isotopic compositions of OIB show mixing between end-members. The end-members
    reflect recycling of different materials into the deep mantle, source of mantle plumes.
    Hotspot dynamics

    Garnero, 2004

    plate-driven mantle flow may focus ascending plumes towards upwellings in the central Pacific
    and Africa as well as into mid-ocean ridges.

    plumes may be captured by strong upwelling flow beneath fast-spreading ridges,


    this may explain why hotspots are more abundant near slow-spreading ridges than fast-spreading ridges

    Jellinek, Gonnermann, and Richards, 2003


    Uncertainty in APM

    Wessel et al., 2006 Steinberger et al, 2006

      Stage motion confirmed by GPS/SLR, sediment, magnetism


      Uncertainty larger with age
      Plate Circuits suggest plume motion
    Plumes and mantle
    convection

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    +-$*5&/($:*;6+*&')677&3&$'+%8*)+5,'(*+,*32"+65$*+-$9*$'+&5$%8*<*+-6)*-,+)",+)*32'*7,59=

    .2'+%$*6"#$%%&'()*;$'$2+-*72)+*5&/($)*)63-*2)*+-$*>2)+*?23&7&3*4&)$*$'+52&'*9,)+*
    @;6+*',+*2%%A*2)3$'/&'(*"%69$)*5$)6%+&'(*&'*7$#*-,+)",+)=

    Jellinek, Gonnermann, and Richards, 2003


    ODP
    Leg 197
    Hawaiian
    Sites
    hotspot track

    0 Ma
    Age-Distance Relationship Among Volcanoes
    of the Hawaiian-Emperor Volcanic Chain

    Ar-Ar Dating Results

    Duncan & Randall, 2004


    Ages of Hawaiian Islands
    Hawaiian Mantle Plume
    • The hotspot volcanism of the Hawaiian Islands is linked to
    the effects of a mantle plume, the core of which is currently
    situated between Kilauea and Loihi volcanoes:
    – The plume contains “enriched” mantle peridotite and appears to
    be heterogeneous.
    – Partial melting near the base of the lithosphere yields the
    observed alkalic (small degrees of partial melt) and tholeiitic
    (larger degrees of partial melt) basalts at the surface.
    Mantle Plume Tail Rising Beneath a
    Lithospheric Plate

    Decompression melting
    occurs at the top of
    plume stem (base of the
    overlying lithosphere).
    Mantle Solidus
    Continuous upwelling and (beginning of melting)
    melt generation over
    time.
    Growth of Kilauea Volcano
    Growth of Hawaiian
    Volcanoes
    Post-erosional alkalic
    Post-shield alkalic

    Ocean Tholeiitic

    Pre-shield alkalic

    Oceanic crust

    Alkalic basalt << 1 vol% Alkalic basalt 1 vol%


    Nephelinite Evolved lavas

    Tholeiites 97-98 vol% Alkalic basalt 1-2 vol%


    Hawaiian Volcano HSDP2 Stratigraphy
    Growth Time

    HSDP I: drilled 1079 m in 1993 (pilot hole)


    HSDP II: drilled 3098 m in 1999 (+recent)
    Bathymetric Map
    (USGS)
    Kea Trend

    Loa Trend
    Motion of the
    Pacific Plate Melt Supply Beneath Hawaii
    ! The HSDP has allowed us
    to model the distribution of
    heterogeneities within the
    upwelling Hawaiian mantle
    plume, in space (3-D) and in
    time.

    ! The deepest (oldest)


    samples represent the time
    when Mauna Kea was
    Kea closest to the center of
    the melting region of the
    Hawaiian plume.

    ! The melting region


    constitutes only the
    innermost, highest
    temperature part of the
    thermally anomalous plume
    mantle.

    Loa

    Bryce et al., G-3, 2005


    Models of Hawaiian Plume Structure

    bilateral asymmetry
    and vertical continuity
    (Abouchami et al., 2005)

    concentrically zoned
    with asymmetric
    heterogeneities
    (Kurz et al., 2004)

    concentrically zoned vertical


    (DePaolo et al., 1991;
    heterogeneities
    Ribe & Christensen, 1999) (Blichert-Toft et al., 2003)
    Horizontal Zoning of the Hawaiian plume
    Bilateral asymmetry and some
    vertical
    vertical
    continuity in the Hawaiian mantle plume

    Concentrically
    Concentrically Zoned
    zoned plume
    with
    with asymmetric
    asymmetric
    heterogeneities
    heterogeneities
    Kurz et al., 2004

    Abouchami et al., Nature, 2005


    Bilateral Asymmetry and Vertical
    Continuity in the Hawaiian Mantle
    Plume

    Abouchami et al., Nature, 2005


    Deccan Traps and
    the Reunion hotspot

    Campbell (2005)

    John Stodder
    Iceland hotspot
    Shield
    volcanoes
    of the
    Galapagos

    Galapagos hotspot
    Fig. 2.9
    Age Progression Example

    Koppers et al.,
    in review
    The figures
    Fig. 7.21
    Fig 1.15
    Fig. 1.17
    Fig. 1.18
    Fig. 1.19
    Fig. 1.20

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