D65: Resources Applications for Oil and Gas Reservoirs

Planning a Section 4.2 application for Acid Gas Disposal? Bottomhole injection pressure, maximum sandface (reservoir) pressure, caprock threshold pressure, fracture propagation pressure, and formation fracture pressure estimates are all required. It is not desirable for acid gas disposal wells to exceed the formation fracture pressure because of possible isolation problems. We recommend a Mini-Frac’ (#DFIT) and Fall-off test, conducted with subsurface pressure recorders (over a Step-Rate test) to optimize your maximum wellhead injection...

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D65: Resources Applications for Oil and Gas Reservoirs

Planning a Water Disposal well application? Disposal refers to the injection of fluids for purposes other than enhanced recovery or gas storage. It is not desirable for water disposal wells to exceed the formation fracture pressure because of possible isolation problems. We therefore recommend a Mini-Frac’ (#DFIT) and Fall-off test, conducted with subsurface pressure recorders (over a Step-Rate test) to optimize your maximum wellhead injection pressure (MWHIP). For facility design, economics, and reservoir engineering we also recommend an...

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D51: Water Injection and Disposal Wells

Planning to convert or drill wells for water injection or effluent disposal? #AER Directive 51 (D51), Section 8.1, outlines initial #welltest requirements for either: 1) Step-Rate Injectivity test, 2) an In-Situ Stress test, or 3) a Mini Frac’ test (DFIT). In my experience the Diagnostic Fracture Injection Test (#DFIT) out-performs the step-rate test for initiating breakover. Perhaps, with each step-rate, the formation actually starts taking water, dissipating frac’ energy? Whereas the rapid increase in pressure, delivered by a...

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Unconventional Testing Alternatives

Mini-Frac’ or DFIT (Diagnostic Fracture Injection Test) is another #welltest alternative that might be worth considering to satisfy #AER Initial oil and gas (#LNG) well test requirements. In horizontal wellbores mini-frac’s can be successful if conducted through the toe port. Another strategy is to complete the multi-stage frac’, clean up the well some, install gauges below the pump and rods, and monitor the pressure for a few weeks, before pump start-up. Schedule a pump workover within 90 days to pull gauges. Analyze the build-up or...

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Unconventional Testing Alternatives

Unconventional #welltest programs include perforation Inflow diagnostic tests (PID), Formation Leak-off tests and Fracture Fall-off tests (FLO), and Mini-Frac’ or Diagnostic Fracture Injection Tests (#DFIT). These simplified methods are now in common usage providing economical alternatives for compliance with #AER Initial Pressure requirements for oil and gas (#LNG) wells. There are several different scenarios, depending on your completion operation logistics. All of them can be analyzed using PITA (pioneered by the author) to generate a p*...

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