Petroleum Migration Quiz

Primary Migration- is understood as the emigration of hydrocarbons from the source rock (clay or shale) into permeable carrier beds ( generally sands or limestones), Secondary Migration – refers to subsequent movement of oil and gas within permeable carrier beds and reservoirs, Tertiary Migration- is movement of a previously formed oil and gas accumulation. A number of lines of observational evidence show that oil and gas do not generally originate in the rock in which they are found, but that they must have migrated into it from elsewhere. This theory is proved by the following observations: 1. As previously discussed, organic matter is easily destroyed by oxidation in porous, permeable sediments at the earth’s surface. It must therefore have invaded the reservoir rock after considerable burial and raised temperature. 2. Oil and gas often occur in solut.