1. n. [Well Testing]
The data observed before the start of radial flow (middle-time transient data). When not dominated by wellbore storage, these data may reveal near-wellbore reservoir features including limited entry, hydraulic fracture, and dual-porosity or layering effects. Downhole shut-in greatly improves the quality of the early-time transient data.
See: bottomhole shut-in, dual-porosity reservoir, hydraulic fracturing, late-time transient data, limited entry, middle-time transient data