The real life alchemists of the 21st century.
Reservoir engineering is a specialised field within petroleum engineering. All hydrocarbons (such as crude oil and gas) are commonly located in subsurface reservoirs. These reservoirs are large rock structures that contain oil within them. Reservoir engineering deals with the overall strategy of extracting oil from a well. Using a long-term perspective, engineers determine the most efficient (cost) and effective way of recovering the available oil in the safest manner. The use of modelling and simulation is able to determine the level of the oil reserves and reservoir depletion.
Compared with the other specialisations in petroleum engineering, reservoir engineers tend to spend most of their time in an office.