In petroleum exploration and development, formation evaluation is used to determine the ability of a borehole to produce petroleum. Essentially, it is the process of "recognising a commercial well when you drill one".

This app includes the following calculation

Basic Core Analysis
Porosity
Oil Saturation

Well Logging
Archies Equation - unknown porosity
Water Saturation
Formation Resistivity Factor
Resistivity Index
Flushed Zone Saturation
Ratio of water saturations
Archies Equation - w/known Porosity
Mud Relationships
Mudcake resistivity
Mud filtrate resistivity
Fluid Resistivity at Temperature

Temperature vs Depth
Temperature at depth
Geothermal Gradient
Formation Resistivity (Correlations)
Sandstone Formations
Carbonate Formations
Low Porosity Carbonate Formations
Spontaneous Potential
Porosity
Density Log
Sonic Log


Great reference for Engineering students and Practice Engineers.