● Petroleum Engineering · Machine Learning RFour Energy Remote-first Subsurface · Production · Applied AI

Petroleum engineering,
with a data-driven hand.

RFour Energy is where petroleum engineering meets machine learning for smarter subsurface and production decisions.

01 / Domain Expertise

Earned, not googled.

Deep field experience in reservoir engineering, production surveillance, and applied AI research — across multiple basin and reservoir types. The list below is what we've actually worked on long enough to break, fix, and explain to someone else.

02 / Technology · Working Stack

What we work with.

/ 01

Python & ML

Forecasting, anomaly detection, physics-informed models — when analytical methods run thin.

/ 02

Applied Deep Learning

Neural networks, ANFIS, physics-informed models — on real wells, not toy datasets.

/ 03

Excel

Material balance, DCA, economics — auditable, transparent, defensible.

/ 04

Dashboards

Production data, well tests, simulation — for the morning meeting, not the demo.

02 / Technology · Approach

How we work a problem.

/ 01

Frame

Start with the operational question, not the algorithm. Most subsurface problems are misframed long before they're modelled — the time spent here saves the rest.

/ 02

Audit

Inventory what's actually there: well tests, production histories, open-hole logs, simulation runs, the Excel tabs that somehow hold the truth. Surface what's signal, what's swamp.

/ 03

Prototype

Build a working model fast — tested against historical events we actually remember, not just train/test splits. If it can't reproduce a known outcome, it isn't ready.

/ 04

Document

Notebooks, an Excel-friendly tool, a serialized model with notes — whatever lets the next engineer pick it up without a phone call.

/ 05

Revisit

Subsurface models age. The ones we keep are the ones we're willing to come back to in six months and disagree with.

03 / Selected Work

Selected work.

● ACTIVE · DEEP LEARNING · RESEARCH
PIDL
Physics-Informed Deep Learning

Gas well health classification — physics-informed neural network

Stability-aware classifier — methodology informing GOWIS.

● AI · PETROPHYSICS
R² 0.997
Petrophysics inference

Petrophysics inference for cap-rock evaluation

Open-hole logs → petrophysical properties. Blind-tested across fields.

● AI · COALBED METHANE
NRMSE 0.032
Unconventional property inference

Unconventional reservoir properties from log data

Multi-property AI inference from open-hole logs.

● AI · COALBED METHANE
R² 0.965
Sorption parameter prediction

Sorption-isotherm parameter inference

Multi-gas AI prediction from laboratory sorption data.

● AI · COMPLETIONS
ANFIS
Completions performance

AI for completions performance estimation

Performance inference from rock + completion parameters.

● PRODUCTION · DELIQUIFICATION
Pilot → Field-wide
Operational scale-up

Gas well deliquification — operational scale-up

Candidate screening, pilot, and field-wide deployment.

● UPSTREAM · FDP
FDP
Field Development

Field development plan — multi-field package

Integrated subsurface, drilling, and facility scope.

● UPSTREAM · SUBSURFACE
Subsurface
Reservoir characterization

Reservoir characterization — residual-oil targeting

Map regeneration to localize undrained zones.

04 / About

Engineering, two disciplines.

[ THE PRACTICE ] ● RE + ML RFOUR ENERGY ·

Field first. Intelligence later.

RFour Energy is forged by petroleum engineers who cut their teeth in the field—mastering the daily grind of subsurface analysis, complex development planning, and the relentless pressure of production. For us, the physical reservoir always came first; the algorithms were built to serve it.

We deploy Machine Learning at the exact point where classical physics gets noisy and conventional spreadsheets reach their limit. Our focus is precision: gas well surveillance, automated diagnostics, deep reservoir inference, and real-time well health classification. The tools showcased here are the refined outputs of our private internal workflows.

RFour Energy serves as the vault for what we architect, code, and occasionally release. We operate without the noise of traditional marketing. This isn't a brand built for the masses; it is a seal of technical integrity for the work we deliver.

Read the full profile →

Multi-asset Field experience across reservoir types
Hundreds Wells analyzed
Multiple Research areas
Multi-tool Open + restricted access
05 / Tools · Flagship

Well and field production monitoring.

Daily production data for gas and oil wells, turned into well-level diagnosis and alerts. Built end-to-end on Cloudflare Workers + D1 with a frontier LLM whose tool calls are grounded in the surveillance data itself — not a chat wrapper over a document.

GOWIS

Gas Oil Intelligence System
agentic AI for surveillance.

Coleman-Turner critical rate · Chan diagnostic · Reciprocal Rate · Ershaghi forecast · Arps DCA · autonomous daily alerts · AI agent.

Upload daily production data for gas and oil wells. For gas wells: Coleman-Turner critical rate, Arps DCA, liquid loading detection, intermittent producer detection. For oil wells: water cut & WOR trends, Reciprocal Rate Method & Ershaghi X-plot for reserves/EUR, Chan diagnostic (coning vs channeling auto-classification). Classify well health into Stable / Warning / Critical / Shut-in, receive autonomous AI alerts when anomalies emerge, and chat with an AI engineer that pulls live data via tool calls.

Open GOWIS
05 / Tools · Library

Tools we've built
and use ourselves.

DCA, material balance, gas well diagnostics, nodal analysis, rate-transient analysis (RTA), rock typing intelligence, and EOR screening — open to anyone who finds them useful.

Excel · Dashboard Agentic AI
View Library
06 / Articles

Field notes.

All articles →

Technical notes on reservoir engineering, production surveillance, decline analysis, and applied machine learning in upstream oil & gas — ordered by theme, from subsurface foundations through the reservoir and the wells to reserves and data science.

Field Development & Asset Management · 12 min

Organizing Subsurface & Production Teams for Mature Fields

A mature field needs a mature organization — a light matrix of three value streams: base management, development & well delivery, and modeling, planning & asset development, with one integrated forecast and a clear governance rhythm.

Read article →
Field Development & Asset Management · 18 min

From exploration well to development plan — the reservoir and petroleum engineer’s role

The reservoir & petroleum engineer’s role across the exploration well lifecycle — planning and data acquisition, drilling execution and well testing, evaluation, reserves, and the development plan.

Read article →
Geoscience Foundations · 11 min

Regional Geology for Non-Geologists

Reading a basin's story in plain language — the petroleum system, basin types, stratigraphy, structural traps, and how to read a cross-section. No degree required.

Read article →
Geoscience Foundations · 11 min

Seismic for Non-Geophysicists

An ultrasound of the earth. Echoes, acoustic impedance, two-way time versus depth, stacking and migration — and how to read horizons, faults, and bright spots on a section.

Read article →
Geoscience Foundations · 15 min

Geomechanics 1D to 4D — What Each Dimension Adds, and What It Costs

The 1D mechanical earth model and its mud weight window, the 2D section and stress polygon, the 3D volume with fault slip tendency, and 4D coupling where depletion moves the stress path — with a plain test for which rung a decision actually needs.

Read article →
Geoscience Foundations · 15 min

Pore Pressure Prediction — Reading the Rock Before the Bit Arrives

Each method assumes a mechanism, and picking the wrong one fails in a predictable direction: compaction trends and Eaton's exponent, the Bowers loading and unloading curves, the centroid in dipping reservoirs, and what actually counts as calibration evidence.

Read article →
Petrophysics & Characterization · 38 min

Low-Resistivity Pay (LRLC) and Low-Quality Reservoir (LQR)

Two different failures with one symptom. Pay can hide because the log lacks contrast — laminated sands, fresh water, conductive minerals — or because the rock cannot flow at all. The six mechanisms, why Archie fails, and the test that tells LRLC apart from a low-quality reservoir: pore-throat classification, capillarity, and whether correcting saturation changes anything.

Read article →
Petrophysics & Characterization · 34 min

Rock Typing Reimagined

A Python, agentic AI, Excel, and dashboard framework for modern reservoir characterization. Six methods, one platform — Winland R35, FZI/HFU, PGS, Lorenz, J-function, and ML on logs.

Read article →
Reservoir Engineering · 40 min

The Complete Guide to Gas Material Balance Analysis

OGIP and drive diagnosis from pressure decline. P/Z, Cole, Roach plots with three worked numerical examples.

Read article →
Reservoir Engineering · 38 min

The Complete Guide to Oil Material Balance Analysis

OOIP and drive diagnosis from pressure decline. Havlena–Odeh straight line, drive indices, and three worked examples whose true answer is known.

Read article →
Reservoir Engineering · 18 min

Reservoir Simulation — What the Model Knows, and What It Only Assumes

From the conservation equations to forecasting practice: discretisation and grid error, the Peaceman well model, where uncertainty concentrates, history matching as an ill-posed problem where a good match can still forecast badly, and the different job simulation does in green versus mature fields.

Read article →
Reservoir Engineering · 22 min

Enhanced Oil Recovery — A Complete Guide

Thermal, gas/miscible, and chemical EOR on one map — steam, SAGD, CO₂, polymer, surfactant, ASP. Mechanisms, screening criteria, and when each method actually pays. Companion screening tool at /eor.

Read article →
Reservoir Engineering · 14 min

CO₂ EOR and Huff & Puff — Two Ways to Use the Same Molecule

Minimum miscibility pressure and what CO₂ does to oil, then the two architectures: a pattern flood limited by sweep rather than displacement, and cyclic single-well huff and puff where soak time and blowdown do the work — with a decision table and what actually kills projects.

Read article →
Reservoir Engineering · 14 min

Nitrogen EOR and Huff & Puff — The Cheapest Gas, and the Hardest to Make Miscible

Made from air on location, yet the reservoir least wants it: the MMP ladder against the fracture limit, gravity-stable crestal displacement where buoyancy becomes the mechanism, and cyclic N₂ driven by repressurization rather than dissolution.

Read article →
Reservoir Engineering · 16 min

Chemical EOR — Polymer, Surfactant, Alkali, ASP, and the Chemical Huff & Puff

Polymer fixes sweep, surfactant fixes trapped oil, alkali makes surfactant affordable, ASP does all three — with the capillary desaturation curve, optimal salinity and the Huh relation, and the cyclic chemical treatment that works by imbibition where no flood can sweep.

Read article →
Production Engineering · 32 min

Reading the Whole Production System

Practitioner's guide to nodal analysis. Where IPR meets VLP, why the operating point is never decided at any single component, and how to translate seventy years of correlations into something that runs on your laptop.

Read article →
Reservoir Engineering · 13 min

Single vs. Commingled Completion — A Production & Reservoir Engineering Comparison

Producing stacked pay zones singly or together, compared from both sides: differential depletion, crossflow and thief zones on the reservoir side; composite IPR, artificial lift and allocation on the production side — with a decision table and the intelligent-completion middle ground.

Read article →
Production Engineering · 10 min

Understanding Coleman-Turner Critical Rate for Gas Wells

Gas wells don't fail because the reservoir runs dry — they fail because liquids win the upward race. Physics, equation, interpretation.

Read article →
Production Engineering · 10 min

Arps decline curve analysis — a practical guide

When to use exponential, hyperbolic, or harmonic. The b-factor as reservoir physics, not a fitting knob.

Read article →
Production Engineering · 11 min

Reciprocal Rate Method — reserves from rate-time data alone

When Arps over-extrapolates, plot 1/q vs Nₙ/q, fit a line, take the inverse slope. A rigorous DCA alternative.

Read article →
Production Engineering · 11 min

Ershaghi X-Plot — waterflood performance & ultimate recovery

Mature waterfloods need a different forecasting tool than rate-time decline. Practical guide with worked example.

Read article →
Production Engineering · 11 min

Chan diagnostic plot — reading water production mechanisms

Coning, channeling, or near-wellbore problem? Read WOR signatures correctly and the workover plan writes itself.

Read article →
Production Engineering · 14 min

Water Shut-Off — Diagnose First, Then Choose the Technology

Problems ranked by how treatable they are, why coning and normal sweep are not candidates, mechanical versus chemical options, disproportionate permeability reduction, and why placement geometry decides the outcome more than the choice of chemical.

Read article →
Production Engineering · 34 min

Workover & Well-Service Candidate Selection — A Systematic Workflow

A physics-first, multidisciplinary workflow from production gap to risked-value ranking — G&G, reservoir, and production engineering. Nodal analysis, a diagnosis-to-intervention map, plus artificial-lift, sand-control, and water shut-off screening, with an end-to-end workflow chart.

Read article →
Production Engineering · 17 min

Hydraulic Fracturing — Candidate, Design, Execution, Diagnosis

Candidate screening on permeability and damage, width models and the conductivity optimum that depends on what is held fixed, fluids and proppant, the Nolte-Smith diagnostic while pumping, monitoring, and the gap between created, propped and effective length — with published field applications.

Read article →
Reserves & Economics · 18 min

Reserves Classification — A Systematic Guide to PRMS

The complete framework under SPE-PRMS 2018 — the two-axis matrix, Reserves/Contingent/Prospective, 1P/2P/3P, P90/P50/P10, project maturity, aggregation, and PRMS vs SEC vs UNFC.

Read article →
Reserves & Economics · 14 min

Hydrocarbon Reserves in Probabilities

Why P50 isn't enough — and how Monte Carlo Simulation transforms volumetric reserves estimation. Distributions, multi-zone aggregation, and tornado analysis.

Read article →
Data Science & ML · 19 min

AI & Machine Learning in Upstream Oil & Gas

A systematic tour across the value chain — seismic CNNs, facies classification, surrogate models, production forecasting, ESP failure prediction, physics-informed ML, and the subsurface pitfalls that sink naive models.

Read article →
Data Science & ML · 26 min

Reverse Engineering, DoE & Machine Learning in Reservoir Engineering

From observed field behavior back to mechanism — inverse problems and history matching, experimental design, ML surrogates, and the tool-assisted agentic AI loop, with a step-by-step Python stack and an exception-based surveillance dashboard, all under physics-first governance.

Read article →
Rock Properties · 26 min

Core Analysis — What the Rock Will Tell You, and What It Won't

RCAL and SCAL end to end — the bias that makes a plug dataset optimistic, the corrections that are often skipped, the cleaning step that destroys wettability, and the laboratory artifact that manufactures residual oil.

Reservoir Fluids · 24 min

PVT — From the Sample to the Number You Trust

Fluid classification, sampling and representativity, the four laboratory studies and what each measures, the differential-to-field-basis conversion nobody checks, and the consistency tests that catch a bad report before it reaches the model.

Workflow & Tooling · 12 min

From Excel to Python — Making Decline-Curve Analysis Reproducible

A decline forecast that cannot be re-run is not a forecast. What has to be true of the code that replaces the workbook — judgements as declared parameters, a bounded Arps fit that raises rather than guesses, and a validation harness reporting blind-test error instead of a single R².

Data Science & ML · 14 min

When the Protocol Passes and the Answer Is Wrong

Four ways a machine-learning result on production data can be wrong while every validation check reports success — an unasked baseline, a model that structurally cannot extrapolate, a score that measured the choosing, and a feature containing its own answer. Each measured on a five-well history.

Geothermal · 10 min

Reservoir Engineering in Geothermal

When the product is heat, not fluid. How petroleum reservoir engineering transfers to geothermal — energy-in-place, material balance, reinjection, and thermal breakthrough.

Read article →
/ Get in touch

Want to talk shop?

Reservoir question, ML approach, dataset you'd like a second pair of eyes on, or just a topic worth discussing — drop a note. Usually replies within a business day.

Message received — RFour Energy team will respond within a business day.
Something went wrong. Please try again or email us directly.