Potential for stabilization

A comment by Kerstan

I found the paper interesting. Although I live outside the
Las Vegas area I have had the opportunity to drive through
the area several times in the last couple of years.  While
I do not find the fact the Las Vegas (LV) basin is
subsiding, I am curious as to whether or not a degree of
predictable subsidence in the overall LV area is
possible.  My curiosity is based the belief that the
subsidence would not necessarily continue unabated forever
as long as groundwater pumping within the LV basin were to
continue.  Could stability eventually result over time.
My hypothesis could best be described as "amateurist" but
here it is anyway.

After a period of time the over-burden mass represented by
the partially compressed LV basin fill plus human structures
could become partially supported by the un-compressed fill
layers below.  In other words, at some point would the mass
of the overlying layers that are now freely compressing (due
to groundwater withdrawal) be supported by the underlying
layers even though the underlying layers represented "open"
soil pore voids.  The individual grains could support
some undetermined weight of overburden without significant
compression and resulting subsidence.  The amount of support
 would be cumulative and when the amount of support exceeded
the weight of the overlying layers plus the human structures
than the degree of support provided by the individual
grains would be sufficient to support the LV basin as a
whole or at least differentially.

If this condition is possible than it would stay static
until additional weight were added or some other change
were to disrupt the static condition.  If such a condition
is possible could it be calculated based on the soil pore
elasticity and grain strength coefficients and thus could
the maximum extent of subsidence be predicted.

Lastly, if such a static condition is possible, would not
a seismic even trigger a catasrophic collapse of the
individual voids between the grains until a new level of
stability were reached.

U.S. Department of the Interior | U.S. Geological Survey
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