1. n. [Drilling Fluids]

A mud test in which the mud sample is not agitated. This test is usually performed at a selected high temperature. Typically, the mud sample is sealed in a mud-aging cell and placed in an oven for a given period of time (often 16 hours, overnight). The cooled mud is tested before it is stirred. Commonly, the sample is retested after it has been stirred. Static-aged mud, before it is stirred, simulates a mud that is static in a well while pipe is out of the hole during a bit trip or logging run. The stirred mud simulates the same mud after arriving at the surface and after being agitated by mud guns and through centrifugal pumps. The amount and kind of mud treatment are determined from these tests.

Alternate Form: static aging test