A set of knowledge domains facilitating Upstream operations:
| Petroleum Geology | Studying reserves structure and volumes |
| Rock Geomechanics | Studying response of rock and rock masses to the forces or displacements |
| Petrophysics | Studying rock properties |
| Well & Log Analysis | Designing and interpretation of well logs |
| Well Testing | Designing and interpretation of well tests |
| Fluid Analysis | Modelling fluids produced from or injected into the petroleum reservoir |
| Reservoir Flow Simulations | Modelling well and reservoir flow dynamics and generating forecasts |
| Drilling Engineering | Designing and executing the well drilling |
| Workover Engineering | Designing and executing workovers |
| Production Technology | Well Performance Analysis and production optimization |
| Subsurface Chemical Engineering | Designing the chemical treatments facilitating well and reservoir performance |
| Field Development Planning | Creating Field Development Plans |
In most common sense this set is equivalent to what is also called Field Study and Modelling.