Columnar joints in basalt, along the Deschutes River, Oregon. These are part of the Columbia River Basalt Group. Photo by Vince Cronin.
Terms that are particularly important for you to understand
Strain terms
angular shear |
anisotropic (anisotropy) |
area strain |
biaxial strain |
coaxial strain |
contraction |
deformation |
displacement vector |
distortion |
elongation |
extension |
finite strain |
heterogeneous |
homogeneous |
infinitesimal strain |
instantaneous strain |
internal rotation |
isotropic (isotropy) |
linear anisotropy |
major axis |
minor axis |
non-coaxial strain |
planar anisotropy |
plane strain |
principal plane of strain |
principal strain |
principal strain axis |
pure shear |
rotation |
shear strain |
simple shear |
strain ellipse |
strain ellipsoid |
stretch |
subsimple shear |
translation |
triaxial strain |
uniaxial strain |
volumetric strain |
|
Stress terms
body force |
deviatoric stress |
differential stress |
intermediate principal stress (σ2) |
maximum (or greatest) principal stress (σ1) |
mean stress |
mega-Pascal |
minimum (or least) principal stress (σ3) |
Mohr circle |
Mohr diagram |
Newton (kg m/s2) |
normal stress |
Pascal (Newton/m2) |
pressure |
principal plane |
principal stress |
principal stress axis |
shear stress |
stress |
stress ellipsoid |
stress tensor |
surface force (or traction) |
total stress |
|
Rheology and mechanics of materials
bulk modulus |
elastic-plastic |
permanent strain |
shear modulus |
viscoelastic (Kelvin) |
constitutive equations |
Hooke's law |
plastic |
steady state |
viscoelastic (Maxwell) |
elastic |
linear elastic |
Poisson's ratio |
strain hardening |
visco-plastic |
elastic perfectly plastic |
perfect elastic |
recoverable strain |
strain rate |
viscous |
elastic with hysteresis |
perfectly plastic |
rheology |
strain softening |
Young's modulus |
Brittle failure
arrest line |
cataclasis |
cataclastic |
conjugate joint set |
crack face |
crack tip |
critical crack growth |
en echelon array |
fault |
fault tip |
hackles |
mixed mode crack |
mode I crack |
mode II crack |
mode III crack |
nucleation point |
opening mode crack |
orthogonal joint set |
plume |
shearing mode crack |
shear |
shear striation |
slickenfiber |
slickenside |
subcritical crack growth |
tearing mode crack |
tip line |
twist hackle |
-- |
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Faults and faulting
back thrust |
balanced cross section |
basement |
blind thrust |
cover sequence |
damage zone |
decollement (reverse fault) |
detachment (normal fault) |
dip slip |
duplex |
fault |
fault-bend fold |
fault core |
fault-propagation fold |
fenster |
flat |
floor thrust |
flower structure |
foreland |
gouge |
graben |
half graben |
high-angle reverse fault |
hinterland |
horse |
horst |
imbricate fan |
klippe |
lateral ramp |
left-lateral |
listric |
low-angle (normal) fault |
mylonite |
net slip |
normal fault |
piercing point |
piggy-back basin |
pop-up |
pull-apart basin |
ramp |
ramp anticline |
releasing bend |
restraining bend |
reverse fault |
right-lateral |
roll-over |
roof thrust |
separation |
shear |
slickenfiber |
shear striae |
slickenside |
slip |
sole thrust |
strike slip |
thrust fault |
tip line |
transcurrent fault |
transfer fault |
transform fault |
Folds
antiform |
nose of a fold |
ptygmatic fold |
Rich-model anticline |
doubly-plunging fold |
synform |
limb |
similar fold |
fault-bend fold |
overturned limb |
homocline |
crest point, curve, surface |
chevron fold |
fault-propagation fold |
overturned fold |
monocline |
culmination |
kink fold |
roll-over |
aspect ratio |
anticline |
trough point, curve, surface |
box fold |
buckle |
inter-limb angle |
syncline |
depression |
harmonic fold |
bend |
fold tightness |
structural dome |
conical fold |
disharmony fold |
flexural fold |
gentle fold |
structural basin |
differential compaction folding |
parasitic fold |
flexural-flow fold |
open fold |
fold train |
median surface |
M-fold |
passive fold |
closed fold |
facing direction |
enveloping surface |
S-surface |
drape fold |
tight fold |
vergence |
wavelength |
Z-fold |
upright fold |
isoclinal fold |
inflection point, curve, surface |
initial wavelength |
drag fold |
inclined fold |
dip isogon |
hinge point, curve, surface |
amplitude |
symmetric fold |
recumbent fold |
fold order |
axial point, curve, surface |
isoclinal fold |
asymmetric fold |
plunging fold |
fold superposition |
cylindrical fold |
parallel fold |
supratenuous fold |
vertical fold |
fold interference |
closure |
concentric fold |
ramp anticline |
horizontal fold |
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In addition to your textbook, the best source for current definitions for all geological terms is the American Geosciences Institute's Glossary of Geology, which you should have a copy of if you are serious about being a geologist.
Klaus K.E. Neuendorf, James P. Mehl, Jr., and Julia A. Jackson [editors], 2011, Glossary of Geology Fifth Edition [revised]: American Geosciences Institute, 800 p., ISBN 978-0-922152-89-6
Available at Amazon.com and other online vendors, or directly through AGI
http://www.agiweb.org/pubs/pubdetail.html?item=300156
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All of the original content of this website is © 2015 by Vincent S. Cronin