MATURATION AND BULK CHEMICAL-PROPERTIES OF A SUITE OF SOLID HYDROCARBONS

In this paper, we present strong correlations of solid hydrocarbon ref lectance (SHR(o)) to vitrinite reflectance (VR(o)) and bulk chemical p roperties (aromaticity, T-max, H/C, etc.). These correlations suggest that, like kerogen in coals and sedimentary rocks, solid hydrocarbons vary systematically during maturation. As a consequence, SHR(o) is esp ecially useful as a maturity indicator in rocks lacking vitrinite, suc h as pre-Devonian rocks and many organic-rich marine rocks. Unlike oth er organic maturation indicators, the utility of solid hydrocarbons is not limited by botanical evolution, but rather the generative potenti al of the petroleum system. Solid hydrocarbons, also known as ''solid bitumen'', ''asphalt'', ''dead oil'', ''migrabitumen'', and ''pyrobitu men'', are genetically defined as solid phase accumulations of predomi nantly hydrocarbons produced by petroleum generation in source rocks. They may occur over a range of concentrations in outcrop and well samp les in all components of petroleum systems. Although accumulations of solid hydrocarbons from exhumed reservoirs are well-reported, the exte nt and utility of disseminated solid hydrocarbons in shales is less un derstood. Solid hydrocarbons are found in organic-rich to very lean, m ature rocks as a residual product of generation. Disseminated solid hy drocarbons exhibit three optical forms; anisotropic (''coked''), ''gra nular'', and relatively uniform (''homogenous''). Only the ''homogenou s'' solid hydrocarbons are recommended for correlation purposes with o ther thermal indicators.