TY - JOUR N2 - The S-7 borehole log from the Sumina area (USCB Poland) revealed the presence of three basaltic veins originating from a basalt dyke. Coal interlayers in the rocks surrounding the basaltic veins have been coked to form natural coke. Photometric measurements revealed that the optical properties of the studied natural coke samples are characteristic of semi-graphite (Rmax > 9%). The natural coke matrix of all of the analyzed samples has a biaxial negative optical character. Vitrinite in the examined natural coke samples is characterized by a lower optical anisotropy than that of the natural matrix and it has a biaxial positive optical character. Vitrinite in almost all samples taken at locations more distant from the intrusion has a biaxial positive optical character. A reversal of the changes of the true maximum vitrinite reflectance and bireflectance with changing distance from the second basaltic vein has been observed. The temperature regime that acted upon the dispersed organic matter located in the immediate vicinity of the intrusion, estimated on the basis of the selected experimental data, is suggested to be higher than 750 °C. L1 - http://journals.pan.pl/Content/108892/PDF-MASTER/7_Adamczyk.pdf L2 - http://journals.pan.pl/Content/108892 PY - 2018 IS - No 2 EP - 249–262 KW - optical properties KW - Natural coke KW - Neogenic intrusion KW - Carbonisation A1 - Adamczyk, Zdzisław A1 - Kokowska-Pawłowska, Magdalena A1 - Komorek, Joanna A1 - Klupa, Agnieszka A1 - Lewandowska, Małgorzata A1 - Nowak, Jacek PB - Komitet Nauk Geologicznych PAN PB - Wydział Geologii UW VL - vol. 68 DA - 2018.06.30 T1 - The impact of a Neogene basalt intrusion on the optical properties and internal structure of the dispersed organic matter in Carboniferous strata (SW-part USCB) SP - 249–262 UR - http://journals.pan.pl/dlibra/publication/edition/108892 T2 - Acta Geologica Polonica ER -