Thermal history of the Carboniferous strata in the northern part of the Intra-Sudetic Basin (SW Poland): A combined Raman spectroscopy and organic petrography study

Raman spectroscopy and vitrinite reflectance measurements of dispersed organic matter from Carboniferous shales in boreholes the northern part Intra-Sudetic Basin were used for thermal history reconstruction. Microscopic investigations have shown that is dominated by maceral group. In analysed samples, shows a varied degree alteration determined mean random (VRo) ranging 0.72% to 3.80%. Mean apparent maximum (R’max) values reached 4.98%. The full width at half D1 G bands spectra are well-correlated with VRo R’max. Thermal maturity regular increase depth. Geological data combined results indicate strata paleotemperatures c. 110 265°C. regional paleogeothermal gradient late Paleozoic was 80°C/km. Variscan heating event presumably caused major coalification process matter. Carboniferous–Permian magmatic activity must contributed high heat flow, adding effect sedimentary burial on maturity.