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Magma-Lithosphere Interaction Chris Havlin1 ([email protected]) Ben Holtzman1, Jim Gaherty1, Patty Lin1, Terry Plank1, Sara Mana1, Natalie Accardo1, Roger Buck1 Mousumi Roy2, Marc Parmentier3, Greg Hirth3, Karen Fischer3, 1. Lamont-Doherty Observatory; 2. University of New Mexico; 3. Brown University

Holtzman and Kendall, G3, 2010 -Lithosphere Interaction

Melt Transport

fracture propagation (magma chambers, dikes, sills, -interaction, eruptions) lith. coupling somewhere between?

porous flow (in a viscously deforming matrix) Magma-Lithosphere Interaction

Melt Transport Lithosphere Inheritance:

fracture propagation shear zones (magma chambers, dikes, sills, fault-interaction, grain size? eruptions) fabric? crust mantle lith. lith. thickness coupling somewhere depleted ?? between? dry

porous flow (in a viscously refertilization? deforming matrix) (metasomatism) Magma-Lithosphere Interaction

Melt Transport Lithosphere Inheritance:

fracture propagation shear zones (magma chambers, dikes, sills, fault-interaction, grain size? eruptions) fabric? crust mantle lith. lith. thickness coupling somewhere depleted ?? between? + dry +

porous flow (in a viscously refertilization? deforming matrix) (metasomatism) Magma-Lithosphere Interaction

Melt Transport Lithosphere Inheritance: I. lithosphere inheritance and fracture propagation shear zones melt migration, accumulation, (magma chambers, grain size? infiltration dikes, sills, fault-interaction, eruptions) fabric? crust II. Intrusional heating mantle lith. lith. thickness coupling somewhere depleted III. Thermal-chemical-mechanical ?? between? + dry feedbacks (in the mantle lith.) +

IV. and the quest porous flow for melt (in a viscously refertilization? deforming matrix) (metasomatism) Magma-Lithosphere Interaction

Melt Transport Lithosphere Inheritance: I. lithosphere inheritance and fracture propagation shear zones melt migration, accumulation, (magma chambers, grain size? infiltration dikes, sills, fault-interaction, eruptions) fabric? crust II. Intrusional heating mantle lith. lith. thickness coupling somewhere depleted III. Thermal-chemical-mechanical ?? between? + dry feedbacks (in the mantle lith.) +

IV. Geophysics and the quest porous flow for melt (in a viscously refertilization? deforming matrix) (metasomatism) Magma-Lithosphere Interaction

Melt Transport Lithosphere Inheritance: I. lithosphere inheritance and fracture propagation shear zones melt migration, accumulation, (magma chambers, grain size? infiltration dikes, sills, fault-interaction, eruptions) fabric? crust II. Intrusional heating mantle lith. lith. thickness coupling somewhere depleted III. Thermal-chemical-mechanical ?? between? + dry feedbacks (in the mantle lith.) +

IV. Geophysics and the quest porous flow for melt (in a viscously refertilization? deforming matrix) (metasomatism) Magma-Lithosphere Interaction

Melt Transport Lithosphere Inheritance: I. lithosphere inheritance and fracture propagation shear zones melt migration, accumulation, (magma chambers, grain size? infiltration dikes, sills, fault-interaction, eruptions) fabric? crust II. Intrusional heating mantle lith. lith. thickness coupling somewhere depleted III. Thermal-chemical-mechanical ?? between? + dry feedbacks (in the mantle lith.) +

IV. Geophysics and the quest porous flow for melt (in a viscously refertilization? deforming matrix) (metasomatism) Magma-Lithosphere Interaction

Melt Transport Lithosphere Inheritance: I. lithosphere inheritance and fracture propagation shear zones melt migration, accumulation, (magma chambers, grain size? infiltration dikes, sills, fault-interaction, eruptions) fabric? crust II. Intrusional heating mantle lith. lith. thickness coupling somewhere depleted III. Thermal-chemical-mechanical ?? between? + dry feedbacks (in the mantle lith.) +

IV. Geophysics and the quest porous flow for melt (in a viscously refertilization? deforming matrix) (metasomatism)

Shallow magma-lithosphere interaction

Strain accomodation/localization, segmentation (e.g., Muirhead et al., G3,2015; Corti et al., 2002; Ebinger and Casey, Geology 2001;)

Dikes, faults and stress (e.g, Hamling et al., Geo., 2010; Nobile et al., GRL 2012; Bedard, GSA Bulletin, 2012) Magma-Lithosphere Interaction

Melt Transport Lithosphere Inheritance: I. lithosphere inheritance and fracture propagation shear zones melt migration, accumulation, (magma chambers, grain size? infiltration dikes, sills, fault-interaction, eruptions) fabric? crust II. Intrusional heating mantle lith. lith. thickness coupling somewhere depleted III. Thermal-chemical-mechanical ?? between? + dry feedbacks (in the mantle lith.) +

IV. Geophysics and the quest porous flow for melt (in a viscously refertilization? deforming matrix) (metasomatism) Melt: where does it go?

Fluid velocity:

pressure gradients driving segregation

compaction pressure

dynamic pressure (matrix shear, stokes) surface tension

porosity

permeability (n between 2,3... 2.6 Miller et al., EPSL 2014)

melt-buoyancy fluid shear viscosity Lithosphere Thickness: Melt Focusing & Decompaction Channels

40 (d) solidus-geotherm intersection 60 (impermeable) 80 z [km]

buoyancy 100

120

140 (de)compaction Sparks and Parmentier, EPSL 1991 Spiegelman, Phil. Trans. 1993 0 20 40 60 80 100 Katz, G3 2010 x [km]

−3 −2.5 −2 −1.5 Amount of focusing depends on how "leaky" the boundary is Havlin et al., in prep. Lithosphere pressure gradients and melt transport

Roy et al., in review Dynamic pressure gradients (matrix shear, stokes flow)

Spiegelman and McKenzie, EPSL 1987 melt Phipps Morgan, GRL 1987 extraction 0 500 100 Strong lithospheric keel 400 moving relative to : Roy et al., in review 350 red curves - melt streamlines 300 arrows - solid flow field contour - temperature 250 melt deflected towards margins 200 km 150 100 50 0 0 200 400 600 800 1000 km Inherited heterogeneity and shear zones: pathways for melt?

Gulf of Aden Grain size and surface tension: Afars smaller grains = more grains in a given volume 1. higher porosity 2. higher surface area for reactions

D1 D2

Tanzania A’ Wark and Watson, GRL, 2000 Congo LV crat on A Lithology? More fusible?

Zambia block

Indian Zimbabwe Ocean -20° craton

30° 50°

Vauchez et al., EPSL, 2005 Gulf of Aden

Afars

Tanzania craton A’

Congo LV crat on A

Zambia block

Indian Zimbabwe Ocean -20° craton

30° 50°

Vauchez et al., EPSL, 2005 Magma-Lithosphere Interaction

Melt Transport Lithosphere Inheritance: I. lithosphere inheritance and fracture propagation shear zones melt migration, accumulation, (magma chambers, grain size? infiltration dikes, sills, fault-interaction, eruptions) fabric? crust II. Intrusional heating mantle lith. lith. thickness coupling somewhere depleted III. Thermal-chemical-mechanical ?? between? + dry feedbacks (in the mantle lith.) +

IV. Geophysics and the quest porous flow for melt (in a viscously refertilization? deforming matrix) (metasomatism) Dike transport: intrusional heating

"Whole-lithosphere" heating (dike height: 10s of km)

"Basal" heating (dike height << 10 km) Dike transport: intrusional heating

"Whole-lithosphere" heating (dike height: 10s of km)

Bialis, Buck and Qin, EPSL, 2010 Time (Myr) Also: Schmeling, Tectonophysics, 2010 Schmeling and Wallner, G3, 2012 "Basal" heating (dike height << 10 km) Dike transport: intrusional heating

"Whole-lithosphere" heating (dike height: 10s of km)

Bialis, Buck and Qin, EPSL, 2010 Time (Myr) Also: Schmeling, Tectonophysics, 2010 Schmeling and Wallner, G3, 2012 "Basal" heating (dike height << 10 km) Dike propagation from melt accumulation zone at low (<0.25) melt fraction (c) (a)

(c) (d)

(b)

Havlin, Parmentier and Hirth, EPSL, 2013 Dike transport: intrusional heating

"Whole-lithosphere" heating higher (dike height: 10s of km) whole-lithosphere heating initial plume impact, (flood basalts!)

Bialis, Buck and Qin, EPSL, 2010 Time (Myr) Also: Schmeling, Tectonophysics,standard 2010 decompression Schmeling and Wallner, G3, 2012 (upwelling in plume tail, "Basal" heating (dike height << 10 km) passive upwelling) basal heating Dike propagation from melt accumulation zone at low (<0.25) melt fraction (c) (a)

(d) (c) melt generation/accumulation rate small scale convection

(b) lower

Havlin, Parmentier and Hirth, EPSL, 2013 Basal heating (Havlin et al., in prep.)

Dry Perid. 0 Solidus Intrusional heating at the LAB:

20 1. Geotherm heated to solidus 2. Porosity front advances 40

60 z [km] 80

100 Temperature Porosity Viscosity 120 18 20 22 24 26 0 500 1000 1500 0 0.01 0.0210 10 10 10 10 T [oC] φ η [Pa s] Basal heating (Havlin et al., in prep.)

Dry Perid. 0 Solidus Intrusional heating at the LAB:

20 1. Geotherm heated to solidus 2. Porosity front advances 40

60 z [km] 80

100 Temperature Porosity Viscosity 120 18 20 22 24 26 0 500 1000 1500 0 0.01 0.0210 10 10 10 10 T [oC] φ η [Pa s] Basal heating (Havlin et al., in prep.)

Dry Perid. 0 Solidus 1D Intrusional heating at the LAB 20 1. Geotherm heated to solidus 40 2. Porosity front advances 30 60 40 z [km] 1550 1475 50 80 60 z [km] 100 70 80 1400 Temperature Porosity Viscosity 90 120 18 20 22 24 26 0 2 4 6 8 10 0 500 1000 1500 0 0.01 0.0210 10 10 10 10 t [Myrs] T [oC] φ η [Pa s] Basal heating (Havlin et al., in prep.)

Dry Perid. 0 Solidus 1D Intrusional heating at the LAB 20 1. Geotherm heated to solidus 40 2. Porosity front advances 30 60 40 z [km] 1550 1475 50 80 60 z [km] 100 70 80 1400 Temperature Porosity Viscosity 90 120 18 20 22 24 26 0 2 4 6 8 10 0 500 1000 1500 0 0.01 0.0210 10 10 10 10 t [Myrs] T [oC] φ η [Pa s] 2D models T, 10 Myrs 0 ]

40 -1 20 No deformation 40 60 60 Former 80 z [km] 80 Lithosphere Strain Rate [s Strain Rate 100 100 Lith. Thickness [km] 120 0 50 100 150 0 50 100 150 0 50x [km] 100 150 x [km] x [km] Magma-Lithosphere Interaction

Melt Transport Lithosphere Inheritance: I. lithosphere inheritance and fracture propagation shear zones melt migration, accumulation, (magma chambers, grain size? infiltration dikes, sills, fault-interaction, eruptions) fabric? crust II. Intrusional heating mantle lith. lith. thickness coupling somewhere depleted III. Thermal-chemical-mechanical ?? between? + dry feedbacks (in the mantle lith.) +

IV. Geophysics and the quest porous flow for melt (in a viscously refertilization? deforming matrix) (metasomatism) Deformation and melt transport in the lithosphere

A preserved LAB in the Ronda Massif

Preserved lithosphere

Partially molten formed during emplacement

reactive melt percolation (refertillization rxn's)

large thermal gradient

melt infiltration and deformation coupled

Soustelle et al., J. Petrology, 2009 Deformation and melt transport in the lithosphere

(a) 5 mm 5 mm 5 mm

)C°(T )C°(T

3 1200

1000 2 800

Mylonites Spinel-tectonites Coarse-granular

11.5 00.5 Distance from the melting front (km) Soustelle et al., J. Petrology, 2009 fa s Deformation and melt transport in the lithosphere

Re-Os model age 3.0 2.0 1.0 0 Age (Ga) 900 Vauchez et al., EPSL, 2005 unaltered craton

0° Labait 1000

Tanzania craton Eastern Rift Tanzania 1100 100 craton A’ + 4% Depth 100 km 1200 (km) Congo LV crat on A 200 km C 0 1300 alteration 300 km Zambia ? P block 1400 150 400 km 200 km Gt free - 4% Gt bearing 1500 0.110 0.120 0.130 0.140

Indian Zimbabwe Ocean -20° craton

30° 50°

CPX vein in gt-hzb. fa s Deformation and melt transport in the lithosphere

Re-Os model age 3.0 2.0 1.0 0 Age (Ga) 900 Vauchez et al., EPSL, 2005 unaltered craton

0° Labait volcano 1000

Tanzania craton Eastern Rift Tanzania 1100 100 craton A’ + 4% Depth 100 km 1200 (km) Congo LV crat on A 200 km C 0 1300 alteration 300 km Zambia ? P block 1400 150 400 km 200 km Gt free - 4% Gt bearing 1500 0.110 0.120 0.130 0.140

W NVH Meru Kilimanjaro E Indian Zimbabwe Ocean 0 km -20° craton a Crust

30° 50° 50 km TC MB

Spinel-Garnet-G

CPX vein in gt-hzb. 100 km 2 3 4 1

150 km

LAB

4.3 km/s 200 km 4.25 km/s

4.2 km/s Low-Velocity 250 km W ManaNVH et al., JGSMeru 2015Kilimanjaro E 0 km b Magma-Lithosphere Interaction

Melt Transport Lithosphere Inheritance: I. lithosphere inheritance and fracture propagation shear zones melt migration, accumulation, (magma chambers, grain size? infiltration dikes, sills, fault-interaction, eruptions) fabric? crust II. Intrusional heating mantle lith. lith. thickness coupling somewhere depleted III. Thermal-chemical-mechanical ?? between? + dry feedbacks (in the mantle lith.) +

IV. Geophysics and the quest porous flow for melt (in a viscously refertilization? deforming matrix) (metasomatism) Geophysics and the search for melt...

Wolbern et al., G3, 2012 Geophysics and the search for melt...

Wolbern et al., G3, 2012 Accardo et al, in prep.

Melt in Afar/MER: Knox et al., GRL, 1998 Keranen et al., Geology, 2004 Bastow et al., G3, 2010 Hammond et al., G3, 2011, 2014 Rooney et al., , 2014 Korostelev et al., GRL, 2015

Visit Natalie's poster T51G-3000, Friday 10am: Rayleigh-wave imaging of upper-mantle shear velocities beneath the Malawi Rift; Preliminary results from the SEGMeNT experiment Geophysics and the search for melt...

Wolbern et al., G3, 2012 Accardo et al, in prep. Ethiopia/Afar

P anomalies 0

Malawi -20 A1

-40

Visit Natalie's poster T51G-3000, Friday 10am: Rayleigh-wave

depth (km) depth imaging of upper-mantle shear velocities beneath the Malawi Rift; Preliminary results from the SEGMeNT experiment -60 A2

-80 0 20 40 60 80 100 120 140

-10-9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 Velocity anomalies (%)

Jakovlev et al., G3, 2013 Geophysics and the search for melt...

Wolbern et al., G3, 2012 Jakovlev et al., G3, 2013 Accardo et al, in prep.

Elastic + anelastic effects: Visit Natalie's poster T51G-3000, Friday 10am: Rayleigh-wave imaging of upper-mantle shear velocities beneath the Malawi Rift; Preliminary results from the SEGMeNT experiment Jackson and Faul, 2010; Jackson et al., 2006,2007 Karato, 2012; Aizawa et al., 2008 McCarthy and Takei, 2011; McCarthy aet al., 2011 .... also anisotropy(CPO, SPO) Gribb and Cooper, JGR, 1998; Sundberg and Cooper, 2010 Holtzman, in review, 2015 0 0 0 0 Quantitative comparisons: Absolute Vs 20 20 20 20 dVs, dVp Synthetics receiver functions 40 40 40 40

Havlin and Parmentier, GRL, 2014 60 60 60 60 Bellis and Holtzman, JGR, 2014 z [km] Olugboji et al., G3, 2013 80 80 80 80 Goes et al., JGR, 2012 Hieronymus and Goes, GJI, 2010

100 100 100 100

120 120 120 120 18 20 22 24 26 0 500 1000 1500 0 0.01 0.02 10 10 10 10 10 4 4.5 5 o V [km/s] T [ C] φ η [Pa s] s Summary

40 Melt transport and inherited lithosphere structure (d)

60 4000 500 1000 initial lithosphere thickness: lateral melt transport 350 80 300 z [km] channelization along the LAB 250 100 200 focusing in thick lithosphere km 120 150 shear zones: 100 140 50 preferential pathways for melt infiltration? 0 0 20 40 60 80 100 0 200 400 600 800 1000 km x [km]

0 Interaction between melt transport & lithosphere 20 Intrusional heating: localizes deformation via thermal weakening 40 rates of basal erosion comparable to whole-lithosphere 60 Former z [km] 80 Lithosphere thermal-chemical modification: 100 120 transport of volatiles, incompatible elements 0 50x [km] 100 150

5 mm 5 mm 5 mm 3.0 2.0 1.0 0 Age (Ga) reactive flow (a) 900 melting of pre-existing fusible heterogeneity Labait volcano 1000

)C°(T )C°(T Tanzania craton Eastern Rift 1100 100 3 + 4% 1200 Depth 100 km 1200 (km) 2 1000 200 km C 0 1300

Geophysical Observations peridotites 800 300 km

Mylonites Spinel-tectonites Coarse-granular ? P 1400 150 11.5 00.5 400 km 200 km Gt free increasingly compelling observations... Distance from the melting front (km) - 4% Gt bearing 1500 0.110 0.120 0.130 0.140

Thank you! (missed some references? want to chat about melt infiltration? [email protected]) ambiguity remains (but there is progress!)