CWD Data Analysis & Reporting 3

Question 1

A time-drawdown graph plotted on semi-log paper shows a straight line. This pattern is characteristic of:

Accepted Answer

Confined aquifer under Theis conditions

Answer

Under Theis conditions, a confined aquifer produces a straight line on a semi-log time-drawdown plot, which is the basis for the Cooper-Jacob analytical method.

Question 2

What information does a gamma-ray log provide during borehole geophysical logging?

Accepted Answer

Indicates clay/shale content by detecting natural radioactivity

Answer

Gamma-ray logs measure natural radioactivity from potassium, uranium, and thorium, which is concentrated in clay minerals and shales, helping distinguish them from cleaner sands and carbonates.

Question 3

When documenting well construction, the gravel pack interval should be recorded as:

Accepted Answer

Top and bottom depths, grain size specifications, and volume placed

Answer

Complete gravel pack documentation requires recording the depth interval, grain size (e.g., 10/20 mesh), and volume placed to verify design specifications were met.

Question 4

During a step-drawdown test, what is the primary data being collected?

Accepted Answer

Drawdown at successively increasing pumping rates

Answer

A step-drawdown test measures water level drawdown at multiple increasing pumping rates to evaluate well efficiency and identify well losses versus aquifer losses.

Question 5

A driller notices the drill cuttings change from gray shale to white quartz sand at 180 feet. How should this be noted on the field log?

Accepted Answer

Record the formation change at exactly 180 feet with descriptions of both formations

Answer

Formation contacts should be logged at the precise depth they are encountered, with descriptions of both the overlying and underlying formations to create an accurate stratigraphic record.

(CWD) Certified Well Driller Practice Test

(CWD) Certified Well Driller Practice Test

CWD Data Analysis & Reporting 3