Glossary
Term | Definition |
---|---|
Sandstone | A sedimentary rock composed primarily of sand sized grains, usually quartz. A common hydrocarbon reservoir rock. |
SCF | Standard cubic feet. See MSCF |
Seal | An impermeable rock unit that prevents hydrocarbons from escaping from the reservoir. |
Sediment | Generally, water borne debris that settles out of suspension. |
Sediment rock | A type of rock formed by aggregation of sediments. |
Seismic reflection | An event observed on seismic data that corresponds to a given rock layer in the subsurface. |
Seismic survey | A tool employing an energy source, such as dynamite, and recording devices used to measure the travel time from a rock layer to the surface. The primary tool used to detect hydrocarbon traps. |
Shale | A very fine grained rock often thinly layered. An important seal rock. |
Show | An indication while drilling that hydrocarbons are present in the well. |
Silt/siltstone | A rock whose grain size is intermediate between sand and shale. |
Source/source rock | An organic rich rock (typically shale) capable of generating hydrocarbons under certain conditions of temperature and pressure. |
STB | Stock tank barrel, the volume of a barrel of oil at the earth's surface as opposed to the corresponding volume in the subsurface. |
Stratigraphy | The study of the vertical and horizontal distribution of stratified rocks, with respect to their age, lateral equivalence, and environment of deposition. |
Structural trap | Generally, a hydrocarbon trap formed by dipping rock layers and/or faults. |
Structure | A geological feature usually higher in elevation than the surrounding rock, formed by local deformation of the rock layers. |