crevprop.crevasse

  1. 2021-2024 J. Mejia

Model Geometry

  • → x

↓ z

‾‾‾‾⎡‾‾‾‾ /‾‾‾‾‾‾‾‾‾ ⎤

⎜ / ⎟ ⎜ <– D(z) –>/ ⎟ ⎜ / ⎟ d -——-/ <— water surface ⎦ ⎜ wwwwww/ ⎜ wwww/ ⎜ ww/ ⎣ crevasse /

depth

STRESS INTENSITY FACTOR For a fracture to propagate

KI >= KIC

stress @ crev tip must >= fracture toughness of ice where KI is the stress intensity factor which describes the stresses at the fracture’s tip the material’s fracture toughness (KIC) STRESS INTENSITY FACTOR For a fracture to propagate

KI >= KIC

stress @ crev tip must >= fracture toughness of ice where KI is the stress intensity factor which describes the stresses at the fracture’s tip the material’s fracture toughness (KIC) Syntax from van der Veen dw = depth to water ( or water depth) = distance from ice surface to

the top of the water column within crevasee

d = crevasse depth = crevasse depth below ice surface b = water height above crevasse tip dw = d - b

  1. Find crack geometry and shape given water input(R, b, Nyrs) and

background stress(sigmaT: + compression, - tensile) and physical

constants(poissons ratio, shear modulus)

Takes into account 1. Elastic opening(based on Krawczynski 2009) 2. Viscous closure(based on Lilien Elmer results) 3. Refreezing rate(diffusion and temperature gradient at sidewalls)

Functions

density_profile(depth[, C, ice_density, ...])

empirical density-depth relationship from Paterson 1994

diff_sq(x, y)

nan_helper(y)

Helper to handle indices and logical indices of NaNs.

sum_over_diff(x, y)

tupled_grid_array(df)

Classes

Crevasse(z, dz, ice_thickness, x, dt, Qin, ...)

Crevasse formed considering elastic, creep, and refreezing