A sedimentary rock composed mainly of calcium carbonate.
The details of rock’s characteristics.
The well site or surface location where a well is to be drilled.
A record of activity or results of plans or surveys. In drilling a well there a number of different kinds of logs, e.g. Downhole density logs, mud logs, driller’s logs etc.
An interruption in the circulation of drilling mud caused by the mud entering a porous zone, fracture or cavity, such that the mud fails to return to the surface.