Bernadetta Pasierb

Bio: Bernadetta Pasierb is an academic researcher. The author has contributed to research in topics: Electrical resistivity tomography. The author has an hindex of 1, co-authored 1 publications receiving 4 citations.

Numerical evaluation of 2D electrical resistivity tomography for subsoil investigations

Abstract: The use of numerical methods for the design and analysis of hydraulic engineering structures requires an accurate determination of the model of subsoil structure. The article presents one of the geophysical methods – electrical resistivity tomography (ERT), which allows for precise, spatially instant recognition of the substrate and the phenomena occurring within it. The methodology, the applied algorithm for numerical calculation, and data processing procedure are discussed. This article also introduces a method of inversion which relies on finding the actual model and presents examples of its application.

Geophysical and geotechnical approach to a landslide stability assessment: a case study

Abstract: Landslides are complex phenomena, and the main factors that have a significant impact on their behavior are changes in slope inclination geometry and changes in water conditions. The main purpose of this work was to evaluate current conditions of the landslide in Brzozowka, near Cracow (Poland), and analyzing how different saturations of soil influence the stability of the landslide. The combination of geophysical and geotechnical research, such as electrical resistivity tomography (ERT), cone penetration testing, drilling and laboratory tests as well as a comprehensive analysis of their results, provided reliable information on the geological structure and geotechnical parameters of the landslide. The results were used in numerical simulations of the landslide stability, in which a two-phase model (soil and water) was assumed that included the effective soil strength parameters and the transient flow conditions as well as a partial saturation zone. The sliding surface obtained from the numerical modeling was almost flat, which was confirmed by the ERT method. It was proved that the landslide occurred when the saturation of the upper part of the slope exceeded 0.8. Obtained results are useful for engineering practice.

Reconstruction of landslide movements using Digital Elevation Model and Electrical Resistivity Tomography analysis in the Polish Outer Carpathians

Abstract: Landslides are a major threat to the environment, infrastructure and human activities, especially in mountainous and hilly areas It is therefore important to accurately identify the mass movements triggering these mechanisms This paper presents the impacts of lithotectonic conditions on the formation of mass movements on the example of the landslide that is located in the northern part of the Polish Outer Carpathians In the area of the research, the ratio of the total area of landslides to the surface of the area reaches even 20% The interpretation of a high resolution Digital Elevation Model (DEM), Electrical Resistivity Tomography (ERT) and fieldwork results allowed for the reconstruction of the landslide movements and dividing them into two areas; the western one, dominated by rotational movement, and the eastern one, featuring rotational and translational movement It was found that the eastern part is more active now as it probably was also in the past, which might have resulted from the lithotectonic conditioned or from the impact of the flowing waters of the Dunajec River Moreover, in the eastern part of the landslides, a small-sized ridge (55 m × 25 m) was identified, which shows greater stability in comparison with the colluvium that surrounds it In order to explain the lower rate of movement of this landform, a morphometric analysis and research using ERT were performed The geophysical measurements showed that the ridge comprised rock formations of greater resistivity than its surroundings It is most likely that the only preserved sandstone packet, constituting the original secondary escarpment, became separated from the bedrock due to rotational movement The presented studies indicate that the landslide was created due to geological and atmospheric conditions A clear revival of landslide movements took place after significant precipitation events that last occurred in the years 2010 and 2015 The bedrock substrate due to its lithology and tectonics, facilitates these movements It was found that the landslide studied is a complex entity, characteristic of the Polish Outer Carpathians, that has undergone multiple stages of development The landslide is active or periodically active and, therefore, must be excluded from the planned development as well as from other forms of human activity

Geophysical and Geochemical Studies on Historical Layers in the Area of Old Krakow, Poland

Abstract: In the present study, application of complementary to each other non-invasive geophysical methods and geochemical slim hole drilling allowed to locate a small fragment of the historical water system, and to determine the type and stratigraphy of the sediments filling it. The most universal, and frequently used geophysical methods are electrical resistivity tomography (ERT) and ground penetrating radar (GPR). These methods are characterized by high precision mapping of the investigated medium, and the possibility of implementation even in small areas. They play an important role in defining the location of archaeological excavations sites. The applied geophysical methods enabled precise and comprehensive analyses of near-surface zones in the area of Planty Park in Krakow (Poland), such as engineering/geological recognition, and detection of anthropogenic structures. As an important metropolis of Central Europe in the medieval period, Krakow due to rapid development of craft and trade had a high demand for water both for the general population and craftsmen. As a result, the city continuously developed and used a complex watercourse and sewage collection system. The layout of the system has not yet been accurately mapped. The authors decided that the ERT method was suitable for this case study. The study was conducted in the eastern part of Planty Park, near Dominikanska Street, measurements were taken using a two-dimensional (2D) parallel layout of ERT profiles. The authors also carried out a three-dimensional (3D) image interpretation process. Even though the ERT method is limited by the requirement of a minimal implementation area, it makes the detection of former watercourses possible. In order to verify the ERT results, three small-diameter mechanical holes drillings were carried for purpose of macroscopic analysis of the ground type with determination of its lithology and layer layout. On gathered samples laboratory measurements of pH, oxidation–reduction potential Eh, and conductivity EC were done. Copyright © 2016 John Wiley & Sons, Ltd.

The application of the 2D/3D electrical resistivity tomography (ERT) method in investigating the carbonate karst of the Zakrzówek Horst

Abstract: A characteristic features of the geological structure of the Krakow area are tectonic horsts and grabens. The Zakrzówek Horst is one of the seven horst structures within the Krakow area, located in the south-western part of the area. It is built of Upper Jurassic limestones, where numerous karst caves have been developed. The caves of the Zakrzówek Horst probably form a system of interconnected caves. This hypothesis has been tested in the western region of the Zakrzówek Horst using the electrical resistivity tomography (ERT) method. The investigations were conducted in the parallel profile configuration as well as with the data processing procedure based on the 2D and 3D inversion. The results of these studies are an attempt to locate additional voids as well as fractured zones in the carbonate rock mass. The studies confirmed the hypothesis that the Jasna Cave is probably only a fragment of a vast cave system developed within the Zakrzówek Horst. As a result of the research carried out with the ERT method, the most prospective directions for future speleological research have been determined.