Versatile Behavior

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. Retrn to message. . . . . . . Thick BEHAVIOR. Ceaseless stream at steady stressLinear, or Newtonian, thick conduct is communicated as:e = (s*t)/visc, where visc = viscosityTypical viscosities for rocks are between 1020 to 1028 Poise. 1 Poise = 1 Pa*secViscous stream happens in the strong earth beneath liquefying temperaturesRate is to a great degree moderate and requires 106 yrs or moreTypical strain rates, e/t =

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Flexible Behavior s = e Strain, e, is directly corresponding to stress E = flexibility or Young's modulus Rock estimations of E are by and large in GPa

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Rock Type Modulus of Elasticity - (MPa x 1000) Limestone 3-27 Dolomite 7-15 Limestone (hard) 70 Sandstone 10-20 Quartz-sandstone 60-120 Greywacke 10-14 Siltstone 3-14 Gneiss - fine 9-13 Gneiss - coarse 13-23 Schist - Micaceous 21 Schist - Biotite 40 Schist - Granitic 10 Schist - Quartz 14 Granite - exceptionally modified 2 Granite - somewhat adjusted 10-20 Granite - great 20-50 Quartzite - Micaceous 28 Quartzite - sound 50-80 Dolerite 70-100 Basalt 50 Andesite 20-50 Amphibolite 90

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Rock Type Modulus of Elasticity - (MPa x 1000) Limestone 3-27 Dolomite 7-15 Limestone (hard) 70 Sandstone 10-20 Quartz-sandstone 60-120 Greywacke 10-14 Siltstone 3-14 Gneiss - fine 9-13 Gneiss - coarse 13-23 Schist - Micaceous 21 Schist - Biotite 40 Schist - Granitic 10 Schist - Quartz 14 Granite - extremely changed 2 Granite - marginally modified 10-20 Granite - great 20-50 Quartzite - Micaceous 28 Quartzite - sound 50-80 Dolerite 70-100 Basalt 50 Andesite 20-50 Amphibolite 90

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Rock name Schmidt Hammer information (this work) Young's modulus-E (GPa) Density-D (kg m - 3 ) Uniaxial quality C 0 (MPa) Source of E Mean bounce back Standard deviation Maresha chalk 23.9 1.4 2.4 ± 1.1 1,220 11 [13] Cordoba-C limestone 41.5 2.2 12.5 ± 0.96 2,070 32 [14] Berea sandstone 50.8 1.9 19.3 2,100 74 [12] Indiana limestone 50.6 1.2 25.3 ± 1.2 2,360 62 [18] Carrara marble 58.6 0.8 39.2 ± 5.6 2,710 95 [16] Gevanim syenite 65.0 1.9 53.4 ± 2.4 2,468 259 This work Mt. Scott stone 73.4 2.7 75.6 2,650 243 This work

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VISCOUS BEHAVIOR Continuous stream at steady anxiety Linear, or Newtonian, gooey conduct is communicated as: e = ( s *t)/visc, where visc = thickness Typical viscosities for rocks are between 10 20 to 10 28 Poise. 1 Poise = 1 Pa*sec Viscous stream happens in the strong earth beneath softening temperatures Rate is to a great degree moderate and requires 10 6 yrs or more Typical strain rates, e/t = 10 - 7/sec to 10 - 14/sec

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SubstanceViscosity (Pa s) Air (at 18 oC) 1.9 x 10 - 5 (0.000019) Water (at 20 oC) 1 x 10 - 3 (0.001) Canola Oil at room temp. 0.1 Motor Oil at room temp. 1 Corn syrup at room temp. 8 Pahoehoe lava 100 to 1,000 A'a lava 1000 to 10,000 Andesite lava 10 6 to 10 7 Rhyolite lava 10 11 to 10 12

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Table 1: Viscosity of Selected Fluids and Materials Fluid/Material Temperature (  C) Viscosity (Pa-s; Pascal-seconds = Newton-seconds/m 2 )* Air 20 1.8  10 - 5 Water 20 1.0  10 - 3 Honey 20 1.6 Flowing hot magma (Hawaiian spring of gushing lava) ~ 1150 ~ 80 Glass ~ 20 ~ 10 12 Ice 0 ~ 10 12 Rock Salt 20 ~ 10 14 Shallow mantle ~ 1000 ~ 10 23 - 10 24 Asthenosphere ~ 1300 ~ 10 19 - 10 20 Deep mantle > 1500 ~ 10 21 - 10 22 *Viscosity is frequently given in units of Poise; 10 Poise = 1 Pa-s.

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Poisson's Ratio Poisson's Ratio, n = e transverse/e longitudinal In uniaxial pressure, an incompressible material ought to have a n = 0.5 Most shakes have n estimations of 0.25 – 0.35

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FRACTURES AND FAULTS

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STRENGTH and DUCTILITY Strength= max worry before disappointment Ductility = max strain before disappointment

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FRACTURES IN ROCKS In uniaxial pressure just augmentation breaks frame. They generally frame parallel to the most extreme compressive anxiety (mcs) and opposite to the minimum compressive anxiety ( which may likewise be a tractable anxiety)

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Shear breaks shape in biaxial and triaxial cases Shear breaks frame at intense points to the mcs The expansion cracks frame the intense bisector Shear breaks overwhelm over augmentation cracks regarding recurrence Faults are huge shear breaks (slip sums > 1 m)

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BRITTLE BEHAVIOR Notice how small splits frame at an opportune time before the unmistakable split happens

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When there is just a single anxiety course, just augmentation breaks frame In biaxial and triaxial cases, shear breaks rule