OIP/GIP Volumetric Calculator: Monte Carlo Uncertainty, Gas PVT & P10/P50/P90 Ranges
Deterministic OOIP/OGIP for four zones, probabilistic P10/P50/P90 from Monte Carlo simulation, and a Bg vs pressure PVT table, complete volumetric toolkit.
TAGLINE
Deterministic OOIP/OGIP for four zones, probabilistic P10/P50/P90 from Monte Carlo simulation, and a Bg vs pressure PVT table — complete volumetric toolkit.
WHO IT'S FOR
Reservoir engineers and geoscientists performing volumetric reserve calculations for well proposals, field development plans, or SPE-PRMS reserve reports requiring probabilistic estimates.
WHAT IT DOES
Calculates OOIP and OGIP for up to 4 zones using standard volumetric equations. Gives a quick ±25% low / base / high range on OOIP. Runs a live 50-iteration Monte Carlo simulation (values change on every recalculation) using triangular and normal distributions for area, net pay, porosity, NTG, Sw, and Bo. Builds a Bg vs pressure PVT table with z-factors solved by Hall-Yarborough from Sutton pseudo-critical properties. Oil volumes are counted only for oil zones and gas only for gas zones.
TABS INCLUDED (9)
• Instructions • Zone Parameters — A, h, phi, NTG, Swi, Boi per zone • OOIP Calculation — OOIP, RF, and recoverable oil by zone + total • OGIP Calculation — OGIP, Bg, and recoverable gas by zone + total • Summary — combined volumetric summary with fluid type breakdown • P10 P50 P90 Ranges — quick ±25% low / base / high OOIP cases • NTG & RF Sensitivity — recoverable oil across NTG and recovery factor • Gas PVT & Bg Table — Bg (RCF/SCF and RB/MSCF) for 13 pressure steps • Monte Carlo OOIP — live 50-run simulation (Zone A) with P90 (low) / P50 / P10 (high) summary
KEY FEATURES
• Monte Carlo: area (triangular), net pay (log-normal), porosity (normal), NTG (triangular), Sw (normal), Bo (normal) — 50 runs sorted and ranked • Gas PVT: Sutton pseudo-critical properties; Hall-Yarborough z-factor solved by Newton iteration • NTG sensitivity: 4 × 5 table of recoverable oil across NTG and RF 20%–40%
TECHNICAL SPECS
• Excel 2016+ compatible • 1,400+ formulas across 9 tabs • 4-zone dataset: Zone A (412 acres, 38.5 ft), Zone B, Zone C oil zones + gas cap • MDT color scheme
ABOUT RESERVOIR RISK SOLUTIONS
Built by petroleum engineers for petroleum engineers. All workbooks require only Microsoft Excel (2016+) — no plugins, no subscriptions. www.reservoir-risk-solutions.com
What you get
- Instant workbook access after payment in your Excel Library
- Formula-driven worksheet designed for petroleum workflows
- No recurring fees and no plugin requirements
Licence
Single-user licence: the purchaser may use and modify this workbook for their own work, including work for their employer and clients. It may not be resold, shared publicly or redistributed as a template. Results are engineering estimates for screening and must be checked by a qualified professional before they are relied on.
FAQ
Is this a one-time purchase?
Yes. Each workbook is sold as a one-time purchase with no recurring subscription.
How do I access purchased files?
After checkout, your file appears in Excel Library under your account for download.
Do these templates require macros or plugins?
No. Templates are designed for Excel 2016+ and do not require VBA macros or external add-ins.
