Geology And Geochemistry Of Oil And Gas.pdf

The progress in the oil and gas industry is related closely to the acceleration of
discovery rates, exploration, development, and production of hydrocarbon resourc-
es. Exploration, development, and production of hydrocarbon resources must be
based on reliable information, which helps to predict subsurface conditions and
properties of oil- and gas-bearing formations.
Main oil and gas reserves are found in sedimentary basins composed of ter-
rigenous (siliciclastic), carbonate, and, sometimes, volcanic or volcaniclastic rocks.
Preservation of high reservoir pressure and good properties of reservoir rocks and
seals (caprocks) in these basins depends greatly on their origin and further evolution.
The process of sedimentation, and the following processes of diagenesis (i.e., phys-
ical, chemical and biochemical processes, which occur in the sediments after sed-
imentation and through lithification at near-surface temperature and pressure) and
catagenesis (or epigenesis) (i.e., physical and chemical processes, which occur in the
sedimentary rocks at high temperatures and pressures after lithification and up to
metamorphism), cause alterations, which may enable one to predict oil and gas
potential.