In addition to diagnostic flow plots, AQTESOLV
also provides derivative analysis to help you choose appropriate aquifer models and solutions methods for
your aquifer test data.
Derivative analysis is a technique popularized
in the petroleum industry (Bourdet et al. 1983) that functions as a
diagnostic tool and supplements curve matching. Simply stated, the derivative is the slope of
drawdown data plotted on a graph with semilog (linear
drawdown and logarithmic time) axes.
A derivative plot displays both drawdown and derivative data
on a single graph. Unlike competing packages, AQTESOLV
allows you to perform interactive visual curve matching on a derivative
plot with both drawdown and derivative data displayed.
Drawdown (squares) and derivative (crosses) data from constant-rate pumping
test in confined aquifer near Gridley, OH (Walton 1962). The derivative
stabilizes (plots at a constant value) when the Cooper-Jacob approximation
becomes valid.
Derivative plot combining drawdown and derivative solutions for a constant-rate
pumping test in a confined aquifer near Gridley, OH.
