1. n. [Drilling Fluids]

The shear stress measured at low shear rate after a mud has set quiescently for a period of time (10 seconds and 10 minutes in the standard API procedure, although measurements after 30 minutes or 16 hours may also be made).

Synonyms: ten-minute gel strength,  ten-second gel strength

See: clay-water interaction,  deflocculant,  deflocculated mud,  direct-indicating viscometer,  drill solids,  flat gels,  funnel viscosity,  gel,  gelation,  gelled-up mud,  gels,  guar gum,  Herschel–Bulkley fluid,  hydrometer,  hydroxyethylcellulose,  Marsh funnel,  mixed-metal hydroxide,  progressive gels,  shear strength,  shear-strength measurement test,  thixotropy,  VG meter,  viscosity,  weighting material,  zero-zero gels