The on-line computational and graphics website for Petroleum engineers & geologists in:
Drilling, Reservoir Engineering, Production, Geosciences & Economics.

by: Dr. Haveluck Gbubemi Harrison
MSc (Imperial), PhD (Heriot-Watt)
E&P Information Management Consultant

AVAILABLE CALCULATIONS (all free!) - New ones are added periodically
Drilling	Surge & Swab pressures
	Bit Hydraulics Optimization
	Cuttings Slip Velocity
	Equivalent Circulation Density Of Mud
	Basic solids analysis
	Drilling rate d-Exponent
	Directional survey
	Well Schematic I - Single vertical completion
	Well Schematic II - Dual vertical completion
	Well Schematic III - Horizontal single completion
	Casing Data Browser
Reservoir I	Material Balance Equation I: SolutionGas-GasCap Drive
	Material Balance Equation II: SolutionGas with GasCap Withdrawal/Injection
	Pressure Buildup Analysis - Horner Plot (Oilwell)
	Inflow Performance Relationships For solution-gas drive Vertical wells
	Inflow Performance Relationships For solution-gas drive Slanted wells
	Inflow Performance Relationships For solution-gas drive Horizontal wells
	Horizontal well performance (oil)
	Water coning in a vertical well
	Combined gas & water coning in a vertical well
	Water breakthrough time in a vertical well
Reservoir II - Gas	Original Gas In Place: Volumetric reservoir - p/z method
	Original Gas In Place: Abnormally Pressured gas reservoir
	Coalbed Methane: Original Gas In Place by P/Z* method
	Coalbed Methane: Reservoir performance prediction
	Gaswell deliverability - Backpressure AOF test
	Horizontal well performance (gas)
	Gas Properties - I: Z, μ, B_g and Sg for a given Composition
	Gas Properties - II: Z, μ, B_g for a given Specific gravity
	Real gas pseudo-pressure
	Gas coning in a vertical well
Production	Decline Curve Analysis
	Flow through chokes (1-phase)
	Flow through chokes (2-phase)
	Gaswell flow in Vertical Tubing
	Gas flow in Horizontal Pipeline
	Gas flow in Inclined Pipeline
	API Gravity Correction to 60°F
	Gas well load-up: Critical Rate
	Tubing Data Browser
	Skin Factors In Perforated Vertical Wells
	Skin Factors In Perforated Horizontal Wells
	Productivity Ratio Of Perforated Horizontal Wells
Geosciences	Contouring
	Conventional well log analysis I
	Conventional well log analysis II
Economics	Basic cashflow analysis
	Comprehensive cashflow analysis (oilfield)
	Comprehensive cashflow analysis (gasfield)
	"Optimum" number of Oilfield development wells
	Project selection/Capital allocation by Ranking method
Miscellaneous	Units Conversion Calculators
	Units Conversion factors
	World Oil & Gas Production & Reserves - Country by country Data
	Mechanical Engineering Calculators
	Civil Engineering Calculators
	Chemical Engineering Calculators