Geology, Geophysics & Environment
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ISSN 2299-8004
e-ISSN: 2353-0790
Issue Date
2019
Volume
Vol. 45
Number
No 3
Description
Journal Volume
Geology, Geophysics & Environment
Vol. 45 (2019)
Projects
Pages
Articles
Results of the comprehensive interpretation of well logs in carbonate and siliciclastic rocks – similarities and differences in the case studies of selected formations
(Wydawnictwa AGH, 2019) Waszkiewicz, Sebastian; Alvarez, Ronal Barcala; Jarzyna, Jadwiga A.
This paper was made using geological and well logging data from the Cuban oilfield area and the Polish Carpathian Foredeep gas deposit to compare the interpretation process and underline similarities and differences between data analysis from two reservoir rocks of different lithology. Data from conventional hydrocarbon deposits, i.e. the Mesozoic Cuban carbonate formation and Miocene shaly-sandy sediments were processed and interpreted using Techlog (Schlumberger Co.) software. Selected approaches were used to determine the step by step volume of shale, total and effective porosity, water/hydrocarbon saturation (Quanti) and for the comprehensive interpretation of well logs (Quanti Elan). Brief characteristics of the carbonate and siliciclastic formations were presented to indicate that the interpretation methodology oriented to the determination of petrophysical properties depends strongly on the type of reservoir. Cross-plots were presented for primary mineral composition recognition, determination of m exponent and resistivity of formation water in the Archie equation. Effective intervals for the carbonate reservoir were calculated according to the Cumulative Hydrocarbon Column methodology. Finally, the results of the interpretation of well logs were presented as continuous curves of mineral composition, including shaliness, porosity and hydrocarbon saturation. The conclusions included recommendations for the effective comprehensive interpretation of well logs in the carbonate and siliciclastic reservoirs.
Relative secular variations of the Earth’s magnetic field in the years 1966–2016 along the profile across the main tectonic units of Poland (Zgorzelec-Wiżajny profile)
(Wydawnictwa AGH, 2019) Wojas, Anna; Grabowska, Teresa
The paper summarizes 50 years of research on relative local secular variations of the total magnetic intensity (TMI) along Zgorzelec-Wiżajny profile (Z-W profile) through the years 1966–2016. The Z-W profile (approximately 650 km length) cuts through Europe’s major tectonic units, including a zone of Variscan folds in the Paleozoic platform (PP), the Trans-European Suture Zone (TESZ) and the Polish part of the East European Craton (EEC). Measurements of TMI were made at 31 sites of the profile and reduced to the base recordings at the Central Geophysical Observatory in Belsk. Based on linear approximations of relative geomagnetic field values changes in time, relative annual changes in time (relative secular variations) expressed in nanoteslas [nT] per year were calculated. The study on relative geomagnetic field values revealed slower secular variations of the geomagnetic field in EEC as compared to those in PP and TESZ. However, they show lower amplitudes of these variations. An interesting phenomenon are rapid changes in the time of the relative values (trends) of TMI starting from the year 2000, also expressed as the relative secular variations per year, particularly visible in PP area. In the qualitative sense, relative secular variations show a correlation with the main geological units in the Polish territory and also important elements in the seismic and geothermal model of the lithosphere.
The effect of de-icing roads with salt on the environment in Krakow (Poland)
(Wydawnictwa AGH, 2019) Kostka, Anna; Strzebońska, Magdalena; Sobczyk, Maciej; Zakrzewska, Marta; Bochenek, Anna
The de-icing of roads and streets in the winter season is a necessity in many European countries, where the mean day temperature drops below 0°C for long periods. Among the many chemicals used for winter road maintenance, the most popular in Poland is sodium chloride in various forms and mixtures, due to its relatively low price and availability. This agent, however, contributes to the increase of salinity in the soil environment and may lead to disturbances in soil properties and premature plant necrosis. The impact of the usage of chloride salts on the soil environment was researched in Krakow’s city centre by means of the examination of soil samples collected prior to the de-icing season (November) and afterwards (February) as well as snow samples taken in February. A general deterioration of the examined parameters (pH, conductivity, chloride concentrations, carbonate concentrations) was observed after the winter season, but still the results for most samples did not pose a serious threat to the soil environment or plants. This was mainly the result of the fact that the winter seasons in European countries have become increasingly mild and warm, which contributes to decreased usage of chloride salts. However, the state of soils in the Main Square was disturbing, as demonstrated by the clearly elevated chemical parameters of samples, despite a ban on the use of salt in this area. These results indicate the most probable reason for the withering of trees growing there, leading to them being frequently replaced.
Modelling of the reactor cycle cost for thorium-fuelled PWR and environmental aspects of a nuclear fuel cycle
(Wydawnictwa AGH, 2019) Oettingen, Mikołaj
The paper presents the methodology applied to the cost modelling of the uranium-thorium nuclear reactor cycle for PWR reactors as well as brief introduction to the environmental impact of the nuclear fuel cycle. The reactor core contains seed uranium fuel and blanket thorium fuel. In such a cycle, energy is produced in the fission of $^{235}$U included in the fresh fuel and in the fission of $^{233}$U bread from the fertile $^{232}$Th. A modified methodology developed by the OECD Nuclear Energy Agency was used for the reactor cycle cost modelling. The method is based on the levelized lifetime cost methodology for a reactor cycle, which is directly related to the heavy metal mass balance. Contrary to the case of uranium-fuelled nuclear reactors, the cost modelling includes the additional cash flow for thorium fuel. The abundance of thorium in the Earth’s crust is about 3–5 times larger than that of uranium, which suggests its promising potential as a nuclear fuel. However, this needs to be proved economically.
Palynofacies analysis of Ida-4 well, Niger Delta Basin, Nigeria
(Wydawnictwa AGH, 2019) Chukwuma-Orji, Jacinta Nkiru; Okosun, Edward Agboneni; Gana, Funmilayo Daramola
Palynofacies analyses of the strata penetrated by Ida-4 wells were carried out with the aim of studying the stratigraphic sequence penetrated by the well in order to establish palynostratigraphic zones, relative age and the paleoenvironment of deposition. Fifty ditch cutting samples within the interval of 2179–3523 m were analyzed. The acid methods of sample preparation for palynofacies analyses were followed. The result of the analyses yielded low to abundant occurrences of pollen and spores with an abundance of small, medium and large sizes of palynomacerals 1 and 2, few occurrences of palynomacerals 3 and 4. The lithology consists of the alternation of shale and sandstone units with few intercalations of argillaceous sandstone units, indicating that the studied interval belongs to the Agbada Formation. The studied intervals were dated to the middle Miocene to late Miocene, based on the recovered age diagnostic marker species such as <i>Zonocostatites ramonae</i>, <i>Multiareolites formosus</i>, <i>Verrutricolporites rotundiporus</i>, <i>Crassoretitriletes vanraadshoveni</i> and <i>Racemonocolpites hians</i>. Two interval range palynostratigraphic zones: <i>Multiareolites formosus – Zonocostatites ramonae</i>, <i>Verrutricolporites rotundiporus - Crassoretitriletes vanraadshoveni</i> and a taxon range zone: <i>Ainipollinite verus</i> zone were proposed. Paleoenvironmental interpretation was based on the palynofacies association and the lithology which revealed that the stratigraphic interval studied was deposited in the Coastal-deltaic (marginal marine) environments.