Log test schedule – In-Situ Win-Situ 2000 Operators Manual User Manual
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0024690 rev. 002 09/00
APPENDIX
where g is the gravitational acceleration for the location of the well in m/
s
2
. P must be in PSI units and L must be in meters.
LOG TEST SCHEDULE
Logarithmic (or simply “log”) sampling optimizes data collection speed
and memory usage for pump and slug tests. The measurements begin
closely spaced and the interval between measurements continuously
increases. The device takes 40 log-normally distributed measurements
per log decade of time. For example, from 10 to 100 minutes,
measurements occur at approximately the following times:
1.
10.0 min.
21.
31.6 min.
2.
10.6 min.
22.
33.5 min.
3.
11.2 min.
23.
35.5 min.
4.
11.9 min.
24.
37.6 min.
5.
12.6 min.
25.
39.8 min.
6.
13.3 min.
26.
42.2 min.
7.
14.1 min.
27.
44.7 min.
8.
15.0 min.
28.
47.3 min.
9.
15.8 min.
29.
50.1 min.
10.
16.8 min.
30.
53.1 min.
11.
17.8 min.
31.
56.2 min.
12.
18.8 min.
32.
59.6 min.
13.
19.9 min.
33.
63.1 min.
14.
21.1 min.
34.
66.8 min.
15.
22.4 min.
35.
70.8 min.
16.
23.7 min.
36.
75.0 min.
17.
25.1 min.
37.
79.4 min.
18.
26.6 min.
38.
84.1 min.
19.
28.2 min.
39.
89.1 min.
20.
29.8 min.
40.
94.4 min
The next log decade, from 100 to 1000 minutes, would look very similar,
but decimal points would be shifted to the right by one place. Similarly,
measurement times in any log decade can be deduced by examining
the decade above, then shifting the decimal point right or left the
appropriate number of places. There may be a slight numerical
difference noted between time values from different logarithmic
TIP: If using a tape measure calibrated in feet, 1 ft = 0.3048
m (exactly).
Note: An error of 0.001 m (1 mm) in the depth measurement
translates into an error of 0.00085 g/cm
3
for density.