Publication details
Thermal maturity of Miocene organic matter from the Carpathian Foredeep in the Czech Republic
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| Year of publication | 2018 |
| Type | Conference abstract |
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| Description | The aim of the research was to determine the thermal maturity of the Miocene sedimentary rocks with the vitrinite reflectance. Based on this information, it is possible to characterize the expected paleo-geothermal gradient within the Carpathian Foredeep in the area of Czech Republic. The Carpathian Foredeep represents a peripheral foreland basin formed due to the tectonic emplacement and crustal loading of the Alpine-Carpathian Thrust Wedge onto the passive margin of the Bohemian Massif. The lithological and stratigraphical content and basin architecture changes in different parts of the basin. Local and regional unconformities are developed due to varying intensity and orientation of flexural loading and different geologic and tectonic histories of the basement, along with a polyphase nature of the active basin margin and gradual change of its position. The basin continues north into the Polish part of the Carpathian Foredeep Basin and south into the North Alpine Foreland Basin. 25 samples from 13 boreholes from the central part of the Carpathian Foredeep were collected. For all those samples, random vitrinite reflectance (Rr) was measured and maceral analysis was performed. Additionally, in order to evaluate regional distribution and depth trends for all of the Carpathian Foredeep, an archive data of vitrinite reflectance from 31 samples from 20 boreholes and results of RockEval pyrolysis (RE) from 107 samples were used. The vitrinite reflectance values (% Rr) in boreholes Got 1, Got 2, Tl 1 and Luk 1 are continuously increasing with the depth from 0.36 % Rr to 0.58 % Rr. In samples from Koryčany 9 and 13 boreholes, the vitrinite reflectance ranges from 0.26 % Rr to 0.28 % Rr, and from Mouchnice 1, 2 boreholes, vitrinite reflectance ranges from 0.27 % Rr to 0.29 % Rr. The vitrinite reflectance of organic matter from the boreholes of Ždánice 135, 147, and 175, Snovídky 1 and Žarošice 2 shows significantly lower values (0.22 % Rr – 0.3 % Rr) compared to other parts of the Carpathian Foredeep. Samples also contain a high ratio of organic matter in which liptinite is significantly represented. Maceral analysis of dispersed organic matter in the sediments of the Carpathian Foredeep enabled to determine dominant maceral composition. The analysis showed that the decisive parameter is the ratio of the liptinite component. |