Consider the data for example Well Elf$-2,$ given in Table $12\mathrm{.}3.$ What are the most likely flow regimes that appear on the diagnostic plot $($Fig$.12\mathrm{.}15$a$)$ before and after early$-$linear flow? Does the test include any possible data from the early$-$radial flow regime? From the late$-$pseudoradial flow regime? From the late$-$linear flow regime? If the answer to any of these questions is "yes," analyze the

Example Well Elf$-2.$ The diagnostic plot $($Fig$.12\mathrm{.}15$a$)$ for a drawdown test from Well Elf$-22^2$ leads us to believe that it includes data in the early$-$linear flow regime because the derivative has a halfslope. We also have the following data on this well:

$q=800ST\frac{B}{D}$

$=1cp$

$B=1\mathrm{.}25R\frac{B}{S}TB$

$r_w=0\mathrm{.}25ft$

$=0\mathrm{.}2.$

$c_t=15{10}^{-6}{}^{-1}$

Centered in box$-$shaped drainage area $100ft$ thick, $4,000ft$

long, $4,000ft$ wide.

$L_w=2,500ft$

From early$-$radial flow regime data, $k_x{k}_z=8,000m{d}^2.$

In addition, we have the pressure$-$time data for this well, as shown by Table $12\mathrm{.}3.$ Our plot of pressure vs$.$ the square root of time $($Fig$.12\mathrm{.}15$b$)$ indicates that we are indeed in early$-$linear flow. The final point on the straight line is at a time of approximately $10$ hours,

of square root of time.