A New Indicator of the Maturity of Organic Matter from Domanik Deposits

Abstract

Abstract —Study of the aromatic fraction of Late Devonian oils and organic matter from domanik deposits of the Timan–Pechora petroleum province has revealed compounds whose proportion depends on the degree of OM transformation, namely, 1,1,7,8-tetramethyl-1,2,3,4-tetrahydrophenanthrene (1,1,7,8-TMHP) and 1,2,8-trimethylphenanthrene (1,2,8-TMP). It has been established that 1,1,7,8-TMHP dominates over 1,2,8-TMP in the immature OM; as the thermal maturation of OM increases, 1,2,8-TMP begins to prevail. The same pattern is observed for the Late Devonian oils. An increase in the ratio of 1,2,8-TMP to 1,1,7,8-TMHP with the growing thermal maturation of OM and the transition of one compound into another permit using this ratio as an additional indicator of OM maturity in domanik rocks.