Geology, Geophysics & Environment
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ISSN 2299-8004
e-ISSN: 2353-0790
Issue Date
2022
Volume
Vol. 48
Number
No 3
Description
Journal Volume
Geology, Geophysics & Environment
Vol. 48 (2022)
Projects
Pages
Articles
Mineralogical characteristics of the heterolithic formations from the Carpathian Foredeep Miocene sediments, south-eastern Poland
(Wydawnictwa AGH, 2022) Przelaskowska, Anna; Zagórska, Urszula; Urbaniec, Andrzej; Łykowska, Grażyna; Klaja, Jolanta; Grela, Jacek; Kędracka, Katarzyna
Heterolithic complexes from the Carpathian Foredeep are a subject of growing attention as many natural gas accumulations of industrial importance have been discovered in such formations during the last decades. The aim of the presented work was to determine lithotypes of different lithology and mineralogical composition in the heterolithic sequences. Individual lithotypes were distinguished of macroscopic observations of cores, X-ray diffraction analysis (XRD) and X-ray fluorescence method (XRF). Preliminary distinction between the lithotypes was based on macroscopic observations of the core samples. Correlation plots between the contents of particular minerals (XRD analyses) and corresponding elements (XRF analyses) were used for verification of the lithotypes distinguished based on macroscopic observations. Swelling properties of the investigated rocks were determined using the cation exchange capacity (CEC) values. The following lithotypes were identified: medium- to fine-grained sandstones, fine- to very fine-grained sandstones, clayey sandstones, sand-dominated heteroliths, heteroliths with approx. equal proportions of sandstones and mudstones, mud-dominated heteroliths, mudstones, clayey shales. Such division provides a basis for precise petrophysical characterization of the analyzed profiles, that is assignment of particular petrophysical parameters values to individual lithotypes. More reliable petrophysical parameters in the geophysical interpretation of heterolithic sequences allow for a more precise determination of zones characterized by good reservoir parameters.
An evaluation of organic matter dispersed in the Menilite Formation in Silesian Nappe (Polish Outer Carpathians): an optical microscopic approach
(Wydawnictwa AGH, 2022) Waliczek, Marta; Machowski, Grzegorz; Solecki, Marek; Stefaniuk, Michał
In this study, optical microscopic analyses were applied to evaluate the thermal maturity, characteristics of solid bitumen, and other organic matter finely dispersed in Oligocene shales of the Menilite Formation in the Iwonicz-Zdrój–Rudawka Rymanowska Fold (IRF) and Bóbrka-Rogi Fold (BRF) of the Central Carpathian Synclinorium of the Silesian Nappe, Outer Carpathians, Poland. The investigation was carried out at two-unit depths of the shallow and deeper D-1 sections (430 m - IRF and 4,300 m - BRF) and outcrop samples (BRF). The mean random huminite reflectance values indicate immature conditions with respect to hydrocarbon generation in samples from the D-1 shallow section ($VR_{o}$ $\approx$ 0.40%) and in the outcrop samples ($VR_{o}$ = 0.36%). The degree of thermal maturity of the organic matter from a depth of about 4,300 m – BRF based on random vitrinite ($VR_{o}$ $\approx$ 0.80%) and solid bitumen ($BR_{o}$ $\approx$ 0.65%) reflectance measurements is associated with the »oil window« for petroleum generation. The organic components dispersed in the examined Menilite Formation samples are typical for hydrocarbon-prone organic matter, suggesting the dominant kerogen type II. The potential precursor maceral for solid bitumen occurring in the examined samples from the deeper D-1 sections is largely the alginite maceral.
Opoka - a mysterious carbonate-siliceous rock: an overview of general concepts
(Wydawnictwa AGH, 2022) Jurkowska, Agata; Świerczewska-Gładysz, Ewa
The opoka is a carbonate-siliceous marine sedimentary rock, forming a thick succession of Upper Cretaceous age in Poland and in another regions of Europe. This rock has been studied for over 150 years, but only the use of modern analytical techniques enables for the formulation of its mineralogical definition, which identifies the distinct features of opoka and allows it to be distinguished from other rocks (e.g. chalk, gaize). Parallel to the petrographic research on opoka, its palaeobathymetric interpretations, which were based on the palaeotectonic models of Danish-Polish Trough inversion has been revised. Depending on the model of palaeotectonic history, opoka has been interpreted as a deep-water or shallow facies, without detailed petrographic studies of its mineralogical composition. The paper presents various aspects of opoka, including: history of the term, nomenclature, mineralogical composition, microtexture and palaeoecological significance of Cretaceous opoka. New data which permit precise definition of this rock term, and its mineralogical composition are discussed in the light of palaeoecological reconstructions, bathymetry and existing models of opoka distribution.
Land use/land cover changes in the period of 2015-2020 in AngYai Village, Sikhottabong District, Vientiane Capital, Lao PDR
(Wydawnictwa AGH, 2022) Thien, Bui Bao; Sosamphanh, Bounthavy; Yachongtou, Bounheuang; Phuong, Vu Thi
In this study, land use/land cover (LULC) changes were identified in AngYai Village, Sikhottabong District, Vientiane Capital, Laos, from 2015 to 2020 using the Geographic Information System (GIS) and remote sensing (RS). Topographic maps and Google Earth Pro satellite imagery data were used with ArcGIS 10.8 software to map land use fluctuations. The study area was classified into the six main types of LULC (agricultural, builtup, forest, main roads, waste land, and water bodies) based on field research, geographical conditions, and RS data. The results indicated sizeable increases in the built-up, main roads, and especially waste land areas over the study period. The forest and agricultural land areas decreased during the study period, possibly due to increased urbanization rates, nomadic cultivation, and indiscriminate deforestation in the study area. The river area was affected by the construction of hydroelectric dams and by the climate, leading to the drying up of water sources and causing water body areas to decrease to some extent.
An examination of the glaciomarginal fan of the Odranian glaciation at the Mokrzeszów site, Sudetic Foreland, SW Poland
(Wydawnictwa AGH, 2022) Krzyszkowski, Dariusz; Wachecka-Kotkowska, Lucyna; Skurzyński, Jacek
The article presents the results of research from the Mokrzeszów site in the Sudetic Foreland. Lithopetrographic and sedimentological analyses of sediments from the Middle Polish Glaciations (Early Saalian, Odranian, MIS6) in this area indicate the overrepresentation (90–95%) of large Scandinavian erratics. The deposits, representing a repetitive sequence of Gp-Gms-Sp-Sh/Sr(Dmm) lithofacies, accumulated during at least two episodes of glacial outburst floods and six sedimentary cycles. High-energy flows are estimated for the Gms and Gp facies at about 5 m $\cdot$ s$^{-1}$ and low-energy flows indicate 0.8 m $\cdot$ s$^{-1}$ for the Sp/Sh/Sr facies, to the lack of flow (Fm). The sedimentary sequences confirm the existence of a fan, which may have originated as a subaqueous steep coarse-grained fan in glacial-flow-lake-outburst floods that formed between the ice sheet front and the morphotectonic edge of the Sudetic Marginal Fault line and within the Roztoka-Mokrzeszów Graben, or as an aerial, piedmont fan on the Sudetic Marginal Fault edge. The sediments show discontinuous deformations – gently sloping faults and fractures from glacioisostatic stresses. The fault activity is probably related to the reactivation of the faults due to ice loading during or after the older Saalian glaciation.