Principal phase of oil formation

Abstract

This paper reviews different theories on the origin and transmission of hydrocarbons in sedimentary rocks. It reviews the diagenetic and catagenetic effects on sediments to mobilize dispersed hydrocarbons into concentrated oil pools. Geochemical information on the hydrocarbons is given along with bituminoid content of sedimentary rocks and recent ocean sediments. Effects of temperature and pressure on the source rocks is provided in graphical form. Attempts are now being made in the USSR to define much more accurately the conditions of the principal phase of oil formation, and its scale and length for different sediments in different oil and gas basins. Attempts are also being made to determine the balance of diagenesis and catagenesis of both organic matter as a whole and bituminoids, including solid, liquid, and gaseous hydrocarbons.