The Oligocene Menilite Beds are considered the most important source rock for hydrocarbon accumulation in the Polish Carpathian region, whereas the Cretaceous Lgota Beds have been regarded as an ...additional potential source rock. Understanding their petrophysical and geochemical properties is essential for evaluating the hydrocarbon potential of these beds.
This paper presents mineral and organic porosity characterization and focuses on factors responsible for the development of organic pores as a reflection of the depositional and diagenetic processes. Mudstones were evaluated as potential source and reservoir rocks, describing their diagenetic and thermal history and examining their effective porosity and permeability. The results show that the Lgota Beds mudstone in the Huczwice quarry is thermally mature (late oil/early gas window, Tmax 460–470 °C), containing type III kerogen and TOC between 0.68 wt% and 4.2 wt%, in contrast to the Menilite Beds mudstone (Monasterzec outcrop), which is thermally immature (Tmax<426 °C), containing type II kerogen and TOC content from 1.24 wt% to 8.7 wt%. The geochemical properties show that the Lgota mudstone is currently an ineffective source rock, whereas the Menilite mudstone can be a potential source rock. SEM-identified pores include mineral pores, organic pores and microfractures. Organic porosity is observable both in immature oil-prone type II kerogen and highly mature gas-prone type III kerogen. The amount of pores in organic matter increases with maturity, and no relation between TOC and organic porosity development has been observed. Palynofacies analysis showed that the Menilite and Lgota mudstones are dominated by amorphous organic matter, and that the Lgota mudstone also contains opaque woody material. MICP measurements indicate high (up to 15%) effective porosity values for the Menilite Beds and up to 8% for the Lgota Beds, with very low permeability values (<0.1 mD) in both cases. Isotherms obtained from nitrogen adsorption are type IV for the Lgota Beds and type II for the Menilite Beds, while the BET surface areas are around 13 m2/g and 3 m2/g, respectively. The Lgota Beds demonstrate advanced diagenetic processes such as compaction, cementation, dissolution, replacement, and transformation, which contributed to the significant reduction in porosity, while the Menilite Beds represent an early stage of burial with the prevailing impact of compaction and thus less destruction of original pores. Finally, the Menilite Beds from the Monasterzec outcrop do not demonstrate sufficient conditions for shale-oil/-gas source rock due to the lack of proper thermal maturity. Such criterion is fulfilled by the Lgota Beds in the Huczwice quarry, but due to very low hydrocarbon potential, the Lgota mudstone is an ineffective source rock. However, given the other petrophysical and geochemical properties, the analysed formations may constitute a basis for further research on the occurrence of unconventional reservoirs in the entire Carpathian region.
•90% of total porosity in Lgota and Menilite Beds mudstones is dominated by nanoporosity .•Organic pores are present in immature and mature mudstones.•No relation exists between TOC and organic porosity development.•The analysed formations may constitute a basis for further research on unconventional reservoirs in the Carpathian region.
Faience objects produced from the fourth millennium BC in ancient Egypt are considered as the first high-tech ceramics in human history. Despite extensive studies on manufacturing technology, many ...aspects of this complex technology remain a mystery and there is no methodology in place to unravel the techniques of Egyptian faience object production. Detailed studies presented herein fill the gaps, verifying standing opinions and allowing certain aspects of faience manufacturing technology to be reconstructed. The object of this innovative investigation is a hemispherical faience bowl discovered by archaeologists excavating a Ptolemaic workshop district at the site of Tell Atrib in the southern Nile Delta. The multiproxy analysis included the application of specialised software and preparation techniques coupled with complementary methods of light and digital microscopy, SEM with EDS, XRD, STA with EGA, as well as image analysis. Sources of raw and accessory materials (mineral and organic binders, fluxes, colourants) used for preparing the silica paste and glaze slurry were determined. The results helped to reconstruct how the raw material was prepared and how faience vessels were made. The bowl was moulded by compression using a two-part mould. The moulded and dried bowl was then covered by glaze slurry using the application method. A synthetic colourant, Egyptian Blue, was probably used to colour the glaze. The item was fired once at a temperature of 1050–1150 °C. Oxidised conditions were maintained in the kiln during the firing process and firing at the maximal temperature was relatively short. Application of the multiproxy approach has shed light on the technological aspects of faience bowl manufacturing. The obtained results have confirmed the usefulness of the comprehensive methodology that was applied for the reconstruction of particular manufacturing stages of faience objects.
The provenance of siliceous grain material, the basic source of manufacturing faience items, is still a matter of discussion. The study methods applied so far have not brought satisfactory outcomes, ...and the results are ambiguous and problematic. Archaeological evidence has also not supplied adequate proof for establishing the sites where the source material was obtained and the methods of its preparation. Therefore, we propose an interdisciplinary approach to solve these research problems. We explore selected material of 7 faience bowls precisely dated on the c. 100 years of the Ptolemaic Period in Egypt. The body and glaze of the faience bowls was qualitatively and quantitatively tested with regard to chemical and mineral composition, and selected material parameters. Based on structural-textural analysis, as well as chemical and mineral composition, the source area of the studied raw material and its potential excavation site was determined in the Eastern Desert. The obtained results were compared with locations of mines exploiting gold-bearing quartz veins, functioning in the Ptolemaic Period. Material parameters obtained from image analysis have been applied to reconstruct the processes of crushing and grinding of the quartz material and its further treatment for faience manufacturing. Quartz treatment was analysed with regard to tools and handling processes applied in Ptolemaic mines. We assume that such an approach has given accurate results in determining the provenance of siliceous material used in the Ptolemaic workshops of Athribis. Therefore, in material studies of artefacts produced in the antiquity, it is indispensable to use an interdisciplinary and complex approach, beginning from field studies and ending with detailed laboratory analyses.
The structural pattern developed within metre to microscopic scale thrust and strike-slip fault zones exposed in the Palaeogene flysch rocks of the Fore-Dukla Thrust Sheet in the south-eastern part ...of the Silesian Nappe, Outer Carpathians, Poland, reveals evidence for upper crustal deformation and fluid flow. Syntectonic dawsonite NaAlCO3(OH)2 indicates the following series of deformational events within the fault zones: i) detachment and buckle folding resulting from movement along thrust faults; ii) faulting as a compensation of the shortening, resulting in the fault propagation folding, breakthrough thrust faulting and imbrications; and iii) strike-slip faulting. The microstructural pattern coupled with the growth of a related sequence of carbonate minerals within the fault zones, followed by present-day dawsonite precipitation and tufa formation, indicate a continuing influence of fluids within the Silesian Nappe up to and including modern time. Structural observations at metre to microscopic scales coupled with EDS mapping of rocks indicate that dawsonite is a unique tool for the reconstruction of subsequent deformation in the Fore-Dukla Thrust Sheet.
•Urartian Red Burnished Ware were imported to Metsamor.•Urartian Red Burnished Ware have different chemical composition than local pottery.•Urartian pottery could not have been produced in the ...pottery workshops producing local ware.
This paper presents a case study on Urartian Red Burnished Ware (URBW) distribution within a provincial Urartian Kingdom settlement through the use of geochemical and petrographic analyses in a comparison of local ceramics. This pottery assemblage study is based on joint Armenian-Polish excavations in Metsamor, specifically from its so-called “outer town” sector. The stratigraphic and chronological evidence indicates that URBW was distributed in the settlement—in small quantities—from 760 to 600 BCE. This analysis proves that URBW was produced in workshops located ∼ 2–3 days travel from the settlement. The intent of importing such vessels was not so much for their functionality but was more likely in response to their individual character. Results suggest that URBW could not be imitated by local potters. Their inability to replicate lustrous red slip was primarily due to technological barriers related to a failure to attain a fully controlled firing process.
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