Is negative buoyancy the primary force driving plate motion during the onset of subduction? A discussion on rock fracture mechanics

doi:10.13745/j.esf.2020.1.28

Abstract

Abstract:

Based on the method of rock fracture mechanics, we discussed in this paper the possibility of pulling force (negative buoyancy) exerted by subducting plate being the driving force for plate movement. Experimental results of rock fracture indicate that the lithospheric strength is very low, only about n×10 MPa, which is unlikely to bear the necessary n×10 ² MPa stress during the onset of subduction. In addition, results from tectonic modeling, thermal cracking, fatigue fracture, flexure of subducted slabs, subduction dehydration and melting process studies reveal that the idea of negative buoyancy of subducting plate being the driving force for plate movement is inconsistent with research observations.

Key words: rock fracture mechanics, driving force for plate movement, negative buoyancy, lithosphere strength

CLC Number:

P541
P584

ZHOU Hui, QIU Liang, YAN Danping. Is negative buoyancy the primary force driving plate motion during the onset of subduction? A discussion on rock fracture mechanics[J]. Earth Science Frontiers, 2020, 27(1): 270-274.

Figures/Tables 2

References 37

[1]	KEAREY P, KLEPEIS K A, VINE F J. Global tectonics[M]. Hoboken: John Wiley & Sons, 2013.
[2]	FORSYTH D, UYEDA S. On the relative importance of the driving forces of plate motion[J]. Geophysical Journal International, 1975, 43(1):163-200. DOI URL
[3]	BUFFETT B A, BECKER T W. Bending stress and dissipation in subducted lithosphere[J]. Journal of Geophysical Research: Solid Earth, 2012, 117:B05413
[4]	CONRAD C P, LITHGOW-BERTELLONI C. How mantle slabs drive plate tectonics[J]. Science, 2002, 298(5591):207-209. DOI URL
[5]	SCHELLART W P. Quantifying the net slab pull force as a driving mechanism for plate tectonics[J]. Geophysical Research Letters, 2004, 31:L07611
[6]	ELSASSER W M. Convection and stress propagation in the upper mantle[J]. Princeton University Technical Report, 1967, 5:23-46.
[7]	臧绍先, 宋杰远. 俯冲带的负浮力及其影响因素[J]. 地球物理学报, 1994, 37(2):174-183.
[8]	TURCOTTE D, SCHUBERT G. Geodynamics: applications of continuum physics to geophysical problems[M]. New York: John Wiley & Sons, 1982.
[9]	GERARDI G, RIBE N M. Boundary element modeling of two-plate interaction at subduction zones: scaling laws and application to the Aleutian subduction zone[J]. Journal of Geophysical Research: Solid Earth, 2018, 123(6):5227-5248. DOI URL
[10]	PITARD P, REPLUMAZ A, FUNICIELLO F, et al. Mantle kinematics driving collisional subduction: insights from analogue modeling[J]. Earth and Planetary Science Letters, 2018, 502:96-103. DOI URL
[11]	ERARSLAN N, WILLIAMS D J. Experimental, numerical and analytical studies on tensile strength of rocks[J]. International Journal of Rock Mechanics and Mining Sciences, 2012, 49:21-30.
[12]	PERRAS M A, DIEDERICHS M S. A review of the tensile strength of rock: concepts and testing[J]. Geotechnical and Geological Engineering, 2014, 32(2):525-546. DOI URL
[13]	KESSON S E, RINGWOOD A E. Slab-mantle interactions: 1. Sheared and refertilised garnet peridotite xenoliths: samples of Wadati-Benioff zones?[J]. Chemical Geology, 1989, 78(2):83-96. DOI URL
[14]	HOPPER J R, BUCK W R. The initiation of rifting at constant tectonic force: role of diffusion creep[J]. Journal of Geophysical Research: Solid Earth, 1993, 98(B9):16213-16221.
[15]	KOHLSTEDT D L, EVANS B, MACKWELL S J. Strength of the lithosphere: constraints imposed by laboratory experiments[J]. Journal of Geophysical Research: Solid Earth, 1995, 100(B9):17587-17602.
[16]	吴晓东, 张福勤. 岩石热开裂的实验研究[J]. 科学通报, 1999, 44(8):880.
[17]	左建平, 周宏伟, 方园, 等. 甘肃北山地区深部花岗岩的热开裂试验研究[J]. 岩石力学与工程学报, 2011, 30(6):1107-1115.
[18]	GOETZE C, EVANS B. Stress and temperature in the bending lithosphere as constrained by experimental rock mechanics[J]. Geophysical Journal International, 1979, 59(3):463-478. DOI URL
[19]	夏琼霞. 大陆俯冲带变质脱水与部分熔融:南大别低温/超高压变质花岗岩研究[D]. 合肥: 中国科学技术大学, 2009.
[20]	李万才, 陈仁旭, 郑永飞. 大陆俯冲带岩石差异变质脱水和部分熔融:以苏鲁造山带超高压正片麻岩为例[J]. 科学通报, 2013, 58(22):2192-2197.
[21]	ZHAO D P, TIAN Y, LEI J S, et al. Seismic image and origin of the Changbai intraplate volcano in East Asia: role of big mantle wedge above the stagnant Pacific slab[J]. Physics of the Earth and Planetary Interiors, 2009, 173(3/4):197-206. DOI URL
[22]	DURETZ T, GERYA T V, MAY D A. Numerical modelling of spontaneous slab breakoff and subsequent topographic response[J]. Tectonophysics, 2011, 502(1/2):244-256. DOI URL
[23]	AKI K. Scattering and attenuation[J]. Bulletin of the Seismological Society of America, 1982, 72(6B):S319-S330.
[24]	KANAMORI H. Seismological evidence for a lithospheric normal faulting: the Sanriku earthquake of 1933[J]. Physics of the Earth and Planetary Interiors, 1971, 4(4):289-300. DOI URL
[25]	STAUDER W. Tensional character of earthquake foci beneath the Aleutian trench with relation to sea-floor spreading[J]. Journal of Geophysical Research Atmospheres, 1968, 73(24):7693-7701. DOI URL
[26]	HALES A L. A seismic discontinuity in the lithosphere[J]. Earth and Planetary Science Letters, 1969, 7(1):44-46. DOI URL
[27]	LLIBOUTRY L. Sea-floor spreading, continental drift and lithosphere sinking with an asthenosphere at melting point[J]. Journal of Geophysical Research Atmospheres, 1969, 74(27):6525-6540. DOI URL
[28]	MORGAN W J. Convection plumes in the lower mantle[J]. Nature, 1971, 230(5288):42-43. DOI URL
[29]	BOTT M H P, KUSZNIR N J. The origin of tectonic stress in the lithosphere[J]. Tectonophysics, 1984, 105(1/2/3/4):1-13. DOI URL
[30]	WORTEL M J R, REMKES M J N, GOVERS R, et al. Dynamics of the lithosphere and the intraplate stress field[J]. Philosophical Transactions of the Royal Society of London, Series A: Physical and Engineering Sciences, 1991, 337(1645):111-126. DOI URL
[31]	FLEITOUT L, MORICEAU C. Topography and geoid anomalies due to density heterogeneities at the base of the thermal lithosphere: application to oceanic swells and small-wavelength geoid lineations[J]. Geophysical Journal International, 1991, 107(2):265-277. DOI URL
[32]	MORGAN W J. Deep mantle convection plumes and plate motions[J]. AAPG Bulletin, 1972, 56(2):203-213.
[33]	BERCOVICI D. The generation of plate tectonics from mantle convection[J]. Earth and Planetary Science Letters, 2003, 205(3/4):107-121. DOI URL
[34]	DAVIES G F, CHRISTENSEN U. Dynamic Earth: plates,plumes and mantle convection[J]. Physics Today, 2000, 53(11):53-54. DOI URL
[35]	TACKLEY P J. Mantle convection and plate tectonics: toward an integrated physical and chemical theory[J]. Science, 2000, 288(5473):2002-2007. DOI URL
[36]	HEURET A, LALLEMAND S. Plate motions, slab dynamics and back-arc deformation[J]. Physics of the Earth and Planetary Interiors, 2005, 149(1):31-51. DOI URL
[37]	TURCOTTE D, SCHUBERT G. Geodynamics[M]. Cambridge: Cambridge University Press, 2014.