Correlation between organic (vitrinite reflectance (Ro) and Rock-Eval Tmax temperature) and inorganic (mixed layer illite/smectite (I/S)) indicators of thermal maturity depend mainly on the maximum temperature achieved by the rock and the time exposure of this temperature. During sedimentary or tectonic burial of rocks, clay minerals may react diversely to organic matter due to heat flow features and the duration of heating (Aldega et al. 2005). The aim of this study was to correlate maximum paleotemperatures of the Oligocene Menilite Shales from the Polish Outer Carpathians determined based on vitrinite reflectance and Rock-Eval pyrolysis data to those calculated using I/S ratio. The analysis was performed on eight claystone samples collected from natural exposures of the Dukla Nappe. Four of them were taken in tectonic windows within the Magura Nappe: Świątkowa and Grybów tectonic windows. All samples were analyzed by vitrinite reflectance, Rock-Eval and smectite to illite conversion. Reflectance of vitrinite and huminite macerals was measured under oil immersion using Carl Zeiss Axioplan microscope in reflected white and blue (fluorescence) light. Standard deviation was calculated for all measurements. The values of Ro were converted into paleotemperatures according to Barker & Pawlewicz (1986). The degree of smectite to illite conversion is shown as the percentage of smectite (%S) in I/S. To define this percentage X-ray powder diffraction was used (Dudek & Środoń 1996 and references therein). Maximum paleotemperatures were estimated according to Sucha et al. (1993). Rock-Eval pyrolysis was conducted on Delsi Instruments apparatus equipped in TOC module to determine: a) total organic carbon content (TOC), b) the amount of residual hydrocarbons generated during pyrolysis of organic matter (S2) and the temperature of maximum of S2 peak (Tmax). The Rock-Eval data indicate that the analysed samples are rich in organic matter, predominantly of oil-prone Type II kerogen. Values of Tmax vary from 421C to 453°C, and were re-calculated into vitrinite reflectance values using equation proposed by Jarvie et al. (2005) and then into paleotemperatures indicating range between 42-153°C. The Ro values vary between 0.45-1.0% indicating paleotemperatures between 51-154°C. The analyzed rocks contain 12-40% S in I/S suggesting paleotemperatures between 104-176°C. Usually, paleotemperatures determined from I/S are higher than those achieved using organic indicators. bIn both, present and previous (Waliczek & Więcław 2013) studies, a strong positive correlation between organic maturity indicators was observed. The good correlation between the organic and inorganic paleotemperature indicators was noticed for all samples collected from tectonic windows of the Dukla Nappe, where organic matter is mature (above 0.7% in Ro scale). For samples containing immature or early-mature organic matter maximum paleotemperatures calculated from I/S data are 40-70°C higher than those calculated based on results of organic matter investigations. The higher maturation of samples from tectonic windows than those from the Dukla Nappe are probably related to the overburden of these rocks by the Magura Nappe. Illitization process is probably time-independent (Pollastro 1993, Środoń 1995) whereas vitrinite reflectance stabilizes in normal burial coalification after about 106-107 years (Barker 1989). The good positive correlation between the organic and inorganic paleotemperature indicators occurs only for samples from tectonic windows which might lead to the conclusion that these sediments were temperature-affected by at least 106 years.
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Celem pracy było rozpoznanie składu mineralnego piaskowców karpackich z sześciu odkrywek, zlokalizowanych pomiędzy przełęczą Kubalonka w Beskidzie Śląskim a doliną Czarnego Potoku w paśmie Jaworzyny Krynickiej w Beskidzie Sądeckim, w aspekcie ustalenia składu petrograficznego obszarów źródłowych z których te piaskowce powstały. Próbki pobrane ze zlokalizowanych w Beskidzie Śląskim profili nr I i II reprezentowały piaskowce istebniańskie. Pozostałe cztery stanowiska, usytowane w Beskidzie Żywieckim, Gorcach oraz Beskidzie Sądeckim, reprezentowały piaskowce magurskie. W każdym profilu pobrano trzy fragmenty skał z poziomu BC. Wykonano analizę mineralogiczną materiału. Piaskowce zawierają w zmiennych ilościach: kwarc, skalenie potasowe, plagioklazy, muskowit, biotyt, węglany, glaukonit, minerały ciężkie, okruchy skał osadowych, magmowych i metamorficznych, substancję organiczną oraz spoiwo. Różnice w udziale poszczególnych składników występują w obrębie tego samego profilu oraz pomiędzy profilami. Piaskowce istebniańskie średnio zawierają większe ilości okruchów skał metamorficznych i osadowych niż piaskowce magurskie. Piaskowce magurskie charakteryzują się natomiast wyższym udziałem kwarcu.
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The aim of the study was to determine mineralogical composition of carpathian sandstones in order to define petrographic composition of the source material areas. The mineralogical composition of the carpathian flysh sandstones collected in six sampling sites was established. The samples collected in the profiles no I and II in Beskid Śląski represent istebniańskie sandstones. The other four sampling sites were located in Beskid Żywiecki, Gorce and Beskid Sądecki and represent magurskie sandstones. Tree samples of rock material were collected in reach sampling profile from the BC horizon. The sandstones contain various amounts of quartz, potassium feldsarps, plagioclase, fragments of sedimentary, magmatic and metamorphic rocks, muscovite, biotite, carbonates, glauconite, heavy minerals, organic matter and binder. There are considerable differences in mineral composition of the sandstone samples taken from six profiles as well as from the same profile. The istebniańskie sandstones contain average higher amounts of metamorphic and sedimentary rocks than the magurskie sandstones. On the contrary, the magurskie sandstones contain higher amounts of quartz.
Heat flow in three Carpathian boreholes was estimated. Such parameters as: thermal conductivity of rocks and geothermal gradient arc needed for heat flow calculation. The laboratory measurements of thermal conductivity of cores from all three boreholes were conducted and the weighted mean thermal conductivity, taking into account the litological differentiation of rocks, was counted. The geothermal gradient was calculated only for Tarnawa-1 borehole, where the temperature data was available. For heat flow estimation in the other boreholes the Carpat-hian average geothermal gradient was used. The obtained results show that both the thermal conductivity and geothermal gradient should be measured in the investigated borehole for proper estimation of the heat flow value.
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