The effects of magma flux variations on the formation and lifetime of large silicic magma chambers

Journal of Geophysical Research: Solid Earth - Tập 118 Số 3 - Trang 926-942 - 2013
Anne Schöpa1, Catherine Annen1
1School of Earth Sciences, University of Bristol, Bristol, UK

Tóm tắt

Incremental emplacement of large silicic intrusions limits the size and lifetime of any magma chamber if earlier injected magma pulses solidify before the next pulse is emplaced. Geochronology indicates that long‐term average magma fluxes of plutons are too low for the accumulation of magma volumes larger than a single pulse. To better constrain the formation of large‐volume magma chambers, we investigate the influence of a changing emplacement rate of successive sill injections that form a composite intrusion in the upper crust. A thermal model with an explicit finite difference scheme simulates periods of transient high magma fluxes keeping the long‐term average flux small. Several scenarios regarding how fluxes vary were analyzed. A progressive increase in flux does not result in magma accumulation. Only a step‐like flux increase of at least one order of magnitude above the background flux produces a large magma reservoir. To generate a magma chamber of a melt‐crystal mix above solidus temperature with a volume of 500–2000 km3, transient high fluxes of at least 1.25 × 10 − 2km3/a, equivalent to vertical, one‐dimensional accretion rates of a few cm/a, are required. The transient high flux range where magma accumulates is largest for model scenarios with one period of transient high flux, and therefore, this emplacement style is favored for the built‐up of substantial magma chambers during pluton growth. Intrusion scenarios with three and four periods of transient high fluxes do not generate reservoirs of mobile magma, but magma mushes can be present for some hundred thousand years.

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Tài liệu tham khảo

10.1130/0016-7606(1988)100<0912:MAAADO>2.3.CO;2

10.1016/j.epsl.2009.05.006

10.1016/S0012-821X(02)00929-9

10.1093/petrology/egi068

10.1029/2007JB005049

10.1130/G19764.1

10.1093/petrology/egh019

10.1016/j.jvolgeores.2005.06.002

10.1017/S0263593300001528

Bateman P., 1992, Plutonism in the central part of the Sierra Nevada batholith, California, US Geological Survey Professional Paper, 1483, 1

10.1130/0016-7606(1979)90<465:CFASOT>2.0.CO;2

10.1093/petrology/33.5.1039

10.1130/0091-7613(1995)023<0213:TRFEEO>2.3.CO;2

10.1144/SP304.11

10.1038/nature09799

10.1016/j.epsl.2007.09.032

10.1144/GSL.SP.1986.024.01.07

Chapman D., 1992, The thermal state of the lower crust, 179

10.1080/00206819709465302

10.1130/G20220.1

Coleman D. J.Bartley A.Glazner andR.Law(2005) Incremental Assembly and Emplacement of Mesozoic Plutons in the Sierra Nevada and White and Inyo Ranges California: Geological Society of America Field Forum Field Trip Guide (Rethinking the Assembly and Evolution of Plutons: Field Tests and Perspectives 7–14 October 2005) 1–59.

Coleman D., 2012, 4D Adamello Conference Abstracts

10.1016/0377-0273(84)90039-8

10.1144/gsjgs.155.5.0853

10.1016/S1464-1895(01)00060-6

10.1007/s00410‐011‐0683‐7

10.1016/j.jvolgeores.2007.07.015

10.1130/G24380A.1

10.1038/nature10706

10.1130/1052-5173(2001)011<0004:TCATGB>2.0.CO;2

10.1029/2001GL013318

10.1130/0091-7613(1996)024<0367:TDCSOT>2.3.CO;2

10.1029/2000JB900029

10.1016/0377-0273(89)90093-0

Gelman S. E., 2012, AGU Fall Meeting Abstracts

10.1093/petrology/egp070

10.1130/0091-7613(1991)019<0784:POSACG>2.3.CO;2

10.1130/1052‐5173(2004)014<0004:APAOMO>2.0.CO;2

10.1144/0016‐76492007‐165

10.1146/annurev.ea.14.050186.002221

10.1007/s004100050276

10.1007/s00410‐003‐0448‐Z

10.1016/j.tecto.2009.10.015

10.1007/BF02600388

10.1093/petrology/41.7.991

10.1007/BF00372365

10.1130/B26054.1

10.1017/S1755691009016089

10.1016/j.epsl.2009.03.029

10.1016/j.jvolgeores.2010.06.006

10.1093/petrology/egq003

10.1016/j.epsl.2011.02.022

10.1130/G32425.1

10.1093/petrology/29.3.599

10.1029/2001JB001050

10.1016/0012-821X(85)90086-X

10.1007/s00445‐003‐0277‐Y

10.1007/s00410‐009‐0444‐Z

10.1130/0091-7613(2001)029<0727:GRODFP>2.0.CO;2

10.1038/NGEO1453

10.1016/j.epsl.2006.03.025

Kistler R. andR.Fleck(1994) Field guide for a transect of the Central Sierra Nevada California: Geochronology and isotope geology US Geological Survey Open‐File Report 94–267 1–50.

10.1007/BF00592937

10.1029/94JB02985

10.1016/j.epsl.2012.01.032

10.1130/GES00061.1

10.1007/BF00371146

10.1029/1999JB900191

10.1130/B25923.1

10.1144/gsjgs.149.2.0221

10.1130/0016-7606(2000)112<119:MEOTMG>2.0.CO;2

10.1130/B30004.1

10.1016/j.epsl.2007.11.043

10.1016/j.tecto.2009.10.016

10.1130/G24546A.1

10.1016/j.tecto.2009.07.011

10.1016/j.jvolgeores.2007.04.019

10.1130/G22604.1

10.1130/2005.fld006(14)

10.1029/2011GL047167

10.1007/s004100100266

10.1093/petrology/41.1.21

10.1007/BF00387198

10.1029/93GL01379

10.1016/j.jvolgeores.2006.11.009

Paterson S., 1996, Pluton emplacement in arcs: A crustal‐scale exchange process, Spec. Pap. Geol. Soc. Am., 315, 115

10.1146/annurev.earth.31.100901.141352

10.1016/S0012-821X(01)00481-2

10.1029/2001JB000315

10.1144/gsjgs.136.6.0627

10.1086/627323

10.1029/2003GC000610

10.1016/0012-821X(76)90008-X

10.1130/0016-7606(2001)113<1486:GAGOMT>2.0.CO;2

10.1007/s00410‐005‐0677‐4

10.1130/0091-7613(2000)28<443:ISUAOZ>2.0.CO;2

Robertson E.(1988) Thermal properties of rocks US Geological Survey Open‐File Report 88–441 1–106.

10.1016/0012-821X(89)90003-4

10.1016/S0012-821X(68)80002-0

10.1029/JB073i016p05207

10.1130/0016-7606(2001)113<0976:ISAEOT>2.0.CO;2

10.1016/j.tecto.2006.07.014

10.1016/j.tecto.2009.12.009

10.1029/2002TC001374

10.1093/petrology/egq064

10.1016/S1367-9120(99)00020-6

10.1144/0016‐764902‐126

10.1007/BF00283225

10.1093/petrology/egs041

10.2475/06.2008.01

10.1130/0091-7613(1992)020<0927:CSEEPS>2.3.CO;2

10.1130/B25689.1

10.1017/CBO9780511807442

10.2113/gselements.3.4.267

10.1007/BF00375359

Schmus W., 1995, Natural radioactivity of the crust and mantle, Global Earth Physics, A Handbook of Physical Constants, AGU Reference Shelf, 1, 283

10.1017/S0263593300001474

10.1093/petrology/37.6.1579

10.1130/G23316A.1

Wessel P., 1991, Free software helps map and display data, Eos Transactions AGU, 72, 445

10.1038/nature07818

10.1093/petrology/29.2.383

10.1016/S0191-8141(98)00059-5

10.1093/petrology/egp023

10.1029/GL014i003p00295

10.1007/s00445‐011‐0525‐5

10.1016/S0191-8141(98)00064-9

10.1130/B25558.1

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Journal of Geophysical Research: Solid Earth

Tập 118 Số 3

926-942

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