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., 2017. Ge netic cor re la tion of source rocks and nat u ral gas in the Pol ish Outer Carpathians and Paleozoic-Mesozoic base ment east of Kraków (south ern Po land). Geo log i cal Quarterly, 61 (4): 795-824, doi: 10.7306/gq.1367 Nat u ral gas-source rock cor re la tions in the Pol ish Outer Carpathians and Paleozoic-Mesozoic base ment in the Kraków-Brzesko-Nowy S¹cz area (south ern Po land) have been es tab lished. In the Dukla and Sub-Silesian units, mixed kerogen Type-II/III or III/II oc curs. The or ganic mat ter is im ma ture or low-ma ture. The Oligocene Menilite beds of the Silesian Unit are rich in TOC and con tain gas-prone Type III kerogen of low ma tu rity. In the Paleozoic-Mesozoic base ment, the TOC con tent and re sid ual hy dro car bon po ten tial vary in the Mid dle and Up per De vo nian strata, Mis sis sip pian car bon ate and clastic fa cies and Mid dle Ju ras sic strata. The Pa leo zoic strata are ca pa ble of thermogenic hy dro car bon gen er a tion, while organic mat ter in the Mid dle Ju ras sic rocks is gen er ally im ma ture. Gas eous hy dro car bons ac cu mu lated both in the Silesian and Dukla units of the Pol ish Outer Carpathians and in the Me so zoic base ment are ge net i cally re lated to thermogenic and mi cro bial pro cesses. The Outer Carpathian nat u ral gas was gen er ated mainly from the Type-II/III kerogen of the Oligocene Menilite beds. The thermogenic gases from the Me so zoic base ment were gen er ated from De vo nian and Mis sis sip pian (carbon ate) Type-II and mixed II/III kerogens and prob a bly from Si lu rian/Or do vi cian Type-II kerogen and Mid dle Ju ras sic Type-III/II kerogen oc cur ring at more than 7 km depth. Mi cro bial meth ane mi grated into the Outer Carpathian flysch suc cession from the Mio cene strata of the Carpathian Foredeep.Key words: Pol ish Outer Carpathians, Pa leo zoic-Mesozoic base ment, source rock po ten tial, nat u ral gas, biomarkers, sta ble car bon, hy dro gen and ni tro gen iso topes.

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Abstract:The Jurassic/Cretaceous stratigraphic complex forming a part of the sedimentary cover of both the eastern Małopolska Block and the adjacent Łysogóry-Radom Block in the Polish part as well as the Rava Rus'ka and the Kokhanivka Zones in the Ukrainian part of the basement of the Carpathian Foredeep were studied with geochemical methods in order to evaluate the possibility of hydrocarbon generation. In the Polish part of the study area, the Mesozoic strata were characterized on the basis of the analytical results of 121 core samples derived from 11 wells. The samples originated mostly from the Middle Jurassic and partly from the Lower/Upper Cretaceous strata. In the Ukrainian part of the study area the Mesozoic sequence was characterized by 348 core samples collected from 26 wells. The obtained geochemical results indicate that in both the south-eastern part of Poland and the western part of Ukraine the studied Jurassic/Cretaceous sedimentary complex reveals generally low hydrocarbon source-rock potential. The most favourable geochemical parameters: TOC up to 26 wt. % and genetic potential up to 39 mg/g of rock, were found in the Middle Jurassic strata. However, these high values are contradicted by the low hydrocarbon index (HI), usually below 100 mg HC/g TOC. Organic matter from the Middle Jurassic strata is of mixed type, dominated by gas-prone, Type III kerogen. In the Polish part of the study area, organic matter dispersed in these strata is generally immature (T max below 435 °C) whereas in the Ukrainian part maturity is sufficient for hydrocarbon generation.

Gaseous emissions from seven self-heating coal waste dumps in two large coal mining basins, Upper and Lower Silesia (Poland), were investigated by gas chromatography (GC-FID/TCD), and the results were correlated with on-site thermal activity, stage of self-heating as assessed by thermal mapping, efflorescences, and surface and subsurface temperatures. Though typical gases at sites without thermal activity are dominated by atmospheric nitrogen and oxygen, methane and carbon dioxide are present in concentrations that many times exceed atmospheric values. On average, their concentrations are 42.7-7160 ppm, respectively. These are levels considered harmful to health and show that coal waste fire can be dangerous for some years after extinction. At thermally active sites, concentrations of CH and CO are much higher and reach 5640-51,976 ppm (aver.), respectively. A good substrate-product correlation between CO and CH concentrations indicates rapid in-dump CH oxidation with only insignificant amounts of CO formed. Other gas components include hydrogen, and C-C saturated and unsaturated hydrocarbons. Decreasing oxygen content in the gases is temperature-dependent, and O removal rapidly increased at > 70 °C. Emission differences between both basins are minor and most probably reflect the higher maturity of coal waste organic matter in the Lower Silesia dumps causing its higher resistance to temperature, or/and a higher degree of overburning there.