Simultaneous Thermal Analysis Method for Studying the Oil Source Rocks

Oil shales and rocks from Domanic formation of the Russian Federation were studied by Rock–Eval and simultaneous thermal analysis (STA) methods. Using the Rock–Eval method, the main geochemical parameters of these oil source rocks were determined, and it was found that the oil shales have a lower content of organic carbon (TOC), a lower thermal maturity and contain kerogen of type II/III, unlike rocks from Domanic deposit, which mainly contain type II kerogen. Using the STA method, the content of organic matter (OM), its fractional composition (FOM), as well as the mineral composition of the rocks in the investigated samples were estimated. It was shown that the STA data cannot only confirm the Rock–Eval data, but also supplement it, providing valuable information about OM and mineral composition of the oil source rock. It was proposed to use the FOM to characterize the OM maturity of source rocks.