Pad Gantt
Completion cost by line item
Per well, expected-value run · share of completion cost
Cycle time by phase
Days, expected-value run
Monte Carlo cycle time
2-year cumulative free cash flow
Pad, before tax, $MM from spud · capex drawn half over drilling, half over completion
All bids on this pad
Expected-value run at the efficiency above · click a row to feature that bid
Vendor bids / rate cards
Editable. Each vendor bids once per fleet type with a multiplier filled in (blank = not offered). Edits update the pad immediately; re-run the sweep to refresh it.
Scenario sweep
Every bid × design × efficiency, expected-value mode. Designs: four archetypes at each lateral length plus six variants of the pad design above.
About / assumptions
Everything here is synthetic. Well, vendor, cost and production numbers are invented, round, public-domain-style values chosen to behave plausibly. Nothing is calibrated to a real operator, basin, vendor or contract. Treat the outputs as a demonstration of method, not as estimates.
Modelled explicitly
- Pad operations as discrete events. Every wireline plug-and-perf run and every frac stage is an event competing for the wireline unit(s) and the frac spread; zipper alternates wells, simul-frac pumps two wells at once (only if the vendor is capable). Then drillout (one unit, wells in series) and rig-out.
- Treating pressure and rate. Surface pressure = frac gradient + net pressure − hydrostatic + pipe friction (Blasius, with friction reducer) + perforation friction + tortuosity. Rate is cut per stage to honour max pressure, available HHP and fleet max rate.
- Non-productive time. Screen-outs, pump failures, wireline misruns, sand/water delays, weather and stuck drillout as random events with lognormal durations (seeded, reproducible). KPIs, cost and the sweep use expected values; the Gantt and Monte Carlo draw them randomly.
- Rate-card contracts. Per-stage price matrices (rate × pressure tiers), per-pump-hour and day-rate pricing, monthly minimums, standby beyond a free allowance, mobilization, volume discounts, fleet-type multipliers and fuel burn by fleet type.
- Economics. Arps hyperbolic oil type curve with terminal decline, scaled by lateral, proppant, fluid and cluster spacing; 2-year before-tax FCF and NPV10 from spud.
Approximated or left out
- Efficiency scales only the swap/transition time between stages relative to a reference of 75%.
- Productivity response to design is a simple power-law with a cluster-interference penalty, not a fracture or reservoir model. No parent/child or well-spacing effects.
- One pressure profile per design (no stage-to-stage rock variability); no casing-integrity, water-sourcing or sand-supply constraints beyond random delays.
- Simul-frac surcharges (×1.35 hourly, ×1.25 day-rate) and standby attribution (wait-on-wireline + half of NPT) are flat rules of thumb.
- Economics are single-pad and before tax; capex timing is two lumps; no price deck, hedges, or facility constraints.
The simulation engine is a line-for-line port of a Python reference implementation and reproduces it to floating-point precision, including the random-number stream.