more study Flashcards
which waves reach a seismometer first after an earthquake
P Waves
which soil horizon is most useful for geologic studies
the B Horizon
what accumulates in a Bt horizon
Clay
what accumulates in a Bk Horizon
Calcium Carbonate
what is reuired for a Vertisol soil to form
Alternating Wet and Dry Seasons
what is the location of water molecules that cause seasonal swelling and closing of cracks in clay rich soil
between the sheets of sheet silica minerals in the soil
why are mafic minerals mre suseptible to chemical weathering than felsic/silic minerals
because the magnitude of their disequilibrium with atmospheric conditions is greater than that of felsic/silic minerals
what is the final step in turning sediment into rock
cementaion of grains via dissolution
what is the basis for assigning names to detrital/clastic sedimentary rocks
clast size
what is the differance between conglomerate and breccia
conglomerant consists of rounded clasts, breccia consists of angular clasts
lithifications of clasts into a conglomerate occurs farther from the clast source area than lithification of clasts into a breccia
if you can see the mineral grains without a microscope what is the rock
schist, which is regional metamorphic
what type of waves cause horizontal shearing below building foundations
Love waves
which rock forms at the deepest level within an organic belt
Gneiss
what is foliation
a predominant orientation of platy and elongate minerals in a metamorphic rock
what is an angular unconformity
when the rocks go from angled and suddenly stop and have a horizonatal layer that cut them off
what is a nonconformity
when a fault ruptures and the headwall goes up retalive to the footwall and splits layers
what type of faults thin the earths crust
Normal Faults
what causes exfoliation
Pressure release as rocks are exhumed
which of the following horizons is likely to be leached the most
the E horizon
why do ooilites form in the carribien sea
water temp is relatively warm
currents are relatively strong
which mineral is most suseptible to chemical weatehring
Olivine
what do index minerals indicate about the metamorphic rock in which they exist
the temp the rock was metamorphized
the pressure the rock was metamorphized
what causes CaCO3 to precipitate out of seawater
warm water
agitation caused by strong currents
agitation b breaking waves
how do you describe the motion casued by P waves
an expansion and contrction in the direction of wave propagation, like a slinky or a sound wave
how do you describe the motion caused by S waves
an up down motion like a cracked whip
how do you describe the motion caused by Love waves
side to side shearing motion
what type of earthquake wave cause movement in every direction
Rayleigh Waves
what is teh focus hypocenter of an earthquake
the location in a 3d coordinate systemwhere a fault rupture initiatesand causes an earthquake
what are surface waves in an earthquake
surface manifestation of bodywaves
what new potential earthquake related hazzards were identified through study of the canterbury earthquake sequence
increased suseptibility to flood and sea level rise
what mechanism reduced teh slope of the heathcote river as a consequence of the NZ Quake
tectonic uplift of the lower part of the heathcote drainage relative to the upper part of the heathcote drainage basin
techtonic subsidence of the upper part of the heathcote drainage relative to the lower part of the heathcote drainage basin
what caused much of the significant damage to the built environment in the NZ earthquake
Liquifaction
how did geologists measure ground movements associated with the NZ quake
LiDAR Surveys
