Environmental Engineering Reference
In-Depth Information
Headphone
Amplifier
Cable
Rock drill
Soil
Boulder
Drill bit
Rock
Geophone
Sound waves
FIGURE 2.58
The elements of the rock indicator, or
acoustical sounding technique, to
differentiate boulders from bedrock.
Free-flowing
artesian well
Topsoil
Sand
Perched ground
water table
Excess hydrostatic
or artesian
pressure
Clay
"static"
groundwater level
(free groundwater
surface)
GWL
−
Sand
Silty
clay
Sand
Clay
Sand
and
gravel
Confined or
artesian water
Rock
FIGURE 2.59
