Doubles For Initial Test… Mini-frac’ or Diagnostic Fracture Injection Tests (#DFIT) help double your #welltest efficiency if pressure gauges are downhole. G-Function analysis estimates closure stress, pore pressure, and leak-off type. After-Closure analysis may provide an estimate of flow capacity (kh) for use in fracture stimulation design. What isn’t specifically clear in #AER D40 is that pressure transient analysis (#PTA) is acceptable for estimating Initial Pressure Oil or Gas (#LNG) conditions (p*). Conceptionally, DFIT is similar to a closed chamber drill stem test (DST) where an impulse (opening valve) generates a pressure build-up response. Also analogous is the negative impulse generated by under-balanced perforating, resulting in a pressure build-up. The mini-frac’ is opposite: a positive impulse causing the pressure to fall-off.