oa ROCK-EVAL PYROLYSIS ON MICRO-PLUGS TO INVESTIGATE SOLID BITUMEN DISTRIBUTION AT DIFFERENT THERMAL MATURITIES

The distribution and type of solid bitumen at different thermal maturities is characterized by a combined approach of organic geochemical and petrographic investigations. Different maturities are present as both naturally achieved as well as by open system pyrolysis of small rock pieces placed into Rock-Eval crucibles. Our first results show, that a certain fraction of the bitumen has a high thermal stability and is detected as the S2 peak rather than S1. Further, the isothermal temperature of 300°C for 3 minutes is not able to fully extract the observable solid bitumen from the rock pieces. In contrast, the amount of solid bitumen in pores increases as well as its reflectivity, indicating remigration from the inner part of the rock towards its surface. Pyrolysis at higher temperatures also creates new solid bitumen filling pores that have been empty in the initial state.