Semi‐brittle deformation of Carrara marble: Hardening and twinning induced plasticity

Abstract Earthquake magnitude is closely related to the depth extent of the seismogenic zone, and higher magnitude earthquakes occur where the seismogenic zone is thicker. The frictional properties of the dominant mineral constituents of the crust, such as feldspar-group minerals, control the depth extent of the seismogenic zone. Here, the velocity dependence of the steady-state friction of anorthite, the calcic endmember of the feldspar mineral series, was measured at temperatures from 20 to 600 °C, pore pressures of 0 (“dry”) and 50 MPa (“wet”), and an effective pressure of 150 MPa. The results support previous findings that the frictional properties of feldspar play a dominant role in limiting the depth extent of the seismogenic zone. This evidence suggests that brittle deformation of anorthite may be responsible for brittle fault movements in the brittle–plastic transition zone.

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Polyphased brittle deformation around a crustal fault: A multi-scale approach based on remote sensing and field data on the mountains surrounding the Têt hydrothermal system (Eastern Pyrénées, France)

Tectonophysics ◽

10.1016/j.tecto.2020.228710 ◽

2021 ◽

pp. 228710

Author(s):

Taillefer Audrey ◽

Milesi Gaétan ◽

Soliva Roger ◽

Monnier Loïs ◽

Delorme Pauline ◽

...

Keyword(s):

Remote Sensing ◽

Hydrothermal System ◽

Field Data ◽

Brittle Deformation ◽

Multi Scale ◽

Eastern Pyrenees

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Super-elastic ferroelectric single-crystal membrane with continuous electric dipole rotation

Science ◽

10.1126/science.aay7221 ◽

2019 ◽

Vol 366 (6464) ◽

pp. 475-479 ◽

Cited By ~ 39

Author(s):

Guohua Dong ◽

Suzhi Li ◽

Mouteng Yao ◽

Ziyao Zhou ◽

Yong-Qiang Zhang ◽

...

Keyword(s):

Energy Landscape ◽

Domain Engineering ◽

Bending Test ◽

Dynamic Evolution ◽

Brittle Deformation ◽

Continuous Transition ◽

Flexible Sensors ◽

Mismatch Stress ◽

Ferroelectric Single Crystal

Ferroelectrics are usually inflexible oxides that undergo brittle deformation. We synthesized freestanding single-crystalline ferroelectric barium titanate (BaTiO3) membranes with a damage-free lifting-off process. Our BaTiO3 membranes can undergo a ~180° folding during an in situ bending test, demonstrating a super-elasticity and ultraflexibility. We found that the origin of the super-elasticity was from the dynamic evolution of ferroelectric nanodomains. High stresses modulate the energy landscape markedly and allow the dipoles to rotate continuously between the a and c nanodomains. A continuous transition zone is formed to accommodate the variant strain and avoid high mismatch stress that usually causes fracture. The phenomenon should be possible in other ferroelectrics systems through domain engineering. The ultraflexible epitaxial ferroelectric membranes could enable many applications such as flexible sensors, memories, and electronic skins.

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Structural glaciology of the fast-moving Jakobshavn Isbræ, Greenland, compared to the surging Bering Glacier, Alaska, U.S.A.

Annals of Glaciology ◽

10.3189/172756400781820543 ◽

2000 ◽

Vol 30 ◽

pp. 243-249 ◽

Cited By ~ 16

Author(s):

Helmut Mayer ◽

Ute Christina Herzfeld

Keyword(s):

Fast Moving ◽

Flow Direction ◽

Kinematics And Dynamics ◽

Similar Data ◽

Brittle Deformation ◽

West Greenland ◽

Video Images ◽

Ice Stream ◽

Bering Glacier

AbstractCrevasse patterns revealing mostly brittle deformation on glacier surfaces are analyzed based on video images collected during systematic overflights of Jakobshavn Isbræ, West Greenland, the Earths continuously fastest moving ice stream, in 1996 and 1997. Crevasse patterns on the surface of the central ice stream are distinct. All crevasses are closed, the surface appears rather smooth. Towards the margins, typical shear patterns with conjugate shears and still-closed crevasses prevail, curved patterns indicate the bending of crevasse lines into the flow direction. Outward from this zone different patterns of open crevasses occur. This suite of patterns is compared to similar data collected over Bering Glacier, Alaska, U.S.A., during its recent surge from 1993–95. There a number of patterns of mostly open crevasses is characteristic: parallel crevasses, two-directional orthogonal open crevasses, arrays of wavy crevasses, en-echelon crevasses. These patterns of the surging glacier are completely different from those of the fast-moving ice stream indicating different underlying kinematics and dynamics.

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