Anna Wojas

Dr. Anna Wojas


Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 May 2020 in International Journal of Earth Sciences
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Journal Article
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HSHenryk Sechman
Henryk Sechman
PGPiotr Guzy
Piotr Guzy
PKPaulina Kaszuba
Paulina Kaszuba
AWAnna Wojas
Anna Wojas
GMGrzegorz Machowski
Grzegorz Machowski
AMAdrianna Maślanka
Adrianna Maślanka
The objective of this paper is to evaluate the relationship between the distributions of direct and indirect, surface geochemical indices in the selected part of the Outer Carpathians. The research included analysis of molecular composition of soil gas samples and calcite contents as well as the measurements of magnetic susceptibility and pH of soil samples. The survey contained 96 soil gas samples collected from 1.2 m depth and 96 soil samples taken from interval 0.7–0.8 m depth. The maximum concentrations of methane, total alkanes C2–C5 and total alkenes C2–C4 were: 2100, 10.43 and 0.772 ppm. The magnetic susceptibility values changed from 3.6 to 21.5 x 10–8 m3/kg. The calcium carbonate contents varied from 0.02 to 29.92 wt% and the pH values measured in soil solutions obtained changed from 4.5 to 8.3. Although the results demonstrate no correlation between the direct soil gas anomalies and the indirect geochemical indicators, the integrated profiles in Fig. 7 suggest possible haloes in the calcite/magnetic data that could be related to hydrocarbons migrating from depth. There are, however, various independent mechanisms that might control the appearance of these mineral anomalies. Secondary changes of mineral composition of soils disclosed by the indirect methods, even if controlled by hydrocarbon migration throughout geological time, might cause some closure of migration pathways, influencing the location of active hydrocarbon migration pathways. Comprehensive interpretation of the results obtained by direct and indirect methods in this paper provides another positive example helping to better understand the complicated mechanism of hydrocarbon migration and the potential usefulness of indirect methods suitable for hydrocarbon exploration.

1 April 2018 in CATENA
Verified
Journal Article
Closed access
MŁMikołaj Łyskowski
Mikołaj Łyskowski
BPBernadetta Pasierb
Bernadetta Pasierb
MWMarta Wardas-Lasoń
Marta Wardas-Lasoń
AWAnna Wojas
Anna Wojas

15 April 2020 in Acta Geophysica
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Journal Article
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Akinniyi AkinsunmadeAkinniyi Akinsunmade
Akinniyi Akinsunmade
CDChau Nguyen Dinh
Chau Nguyen Dinh
AWAnna Wojas
Anna Wojas
STSylwia Tomecka-Suchoń
Sylwia Tomecka-Suchoń
Gridded aeromagnetic and aeroradiometric datasets of Isanlu sheet 225 were processed and interpreted in order to map the geological structures and characteristic lithology, as well as potential mineral ore zones in the area. Recorded aeromagnetic data were reduced to the magnetic equator before filtering operations which enhanced the magnetic anomalies. Analytic signal map was created, and subsequently a model was generated along a selected profile for better interpretation of the subsurface materials. On the aeroradiometric data were performed both enhancement and statistical operations. The lithological zones were identified. They are metasedimentary rocks, migmatites and igneous rocks occupying varying proportions within the entire area. Some potential radioactive or precious metal ore zones were also localized. A major structure interpreted in the study area trends in the SE–NW direction. Other surface structures were also delineated and general orientation was evaluated. This information may serve as a valuable database for further prospective research and mineral exploration in the region.

3 May 2017 in Acta Geophysica
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Journal Article
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AWAnna Wojas
Anna Wojas

25 July 2022 in Preprints.org
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Preprint
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AWAnna Wojas
Anna Wojas
The paper concerns the distribution of apparent magnetic susceptibility in soil profiles located in the areas of topsoil magnetic susceptibility anomalies in Krakow. The type of land use, possible sources of magnetic carriers, and the type of soil were taken into account. Additionally, at each soil profile, a comparison between soil magnetic susceptibility and the results of geochemical analyzes of soil samples was made. The study shows very characteristic changes in magnetic susceptibility with depth, reflecting the interdependencies between natural and anthropogenic factors. A visible magnetic susceptibility maximum at the depth of 10-30 cm is observed at each soil profile. The maximum is associated mainly with the deposition of atmospheric dust and its vertical range depends on the level of anthropopression and natural conditions of soils. At the depth above 40 cm in the eastern part of Krakow, a correlation between the magnetic susceptibility and the soil type (chernozems de-veloped on loess) was found. All indicates that the thicknesses of contaminated upper horizons are not accidental and they depend on human interactions with the environment and the type of soil. An attempt at template establishment with the sources of magnetic particle carriers for different places in the city was made. As the result, in high urbanized sites, the extreme values of magnet-ic susceptibility rapidly change in short vertical distances can identify the richness of anthropo-genic layers with various types of anthropogenic ferrous material and/or additionally Fe-carrying objects buried in soils. In industrialized sites, anthropogenic input plays the most important role in the creation of soil magnetic characteristics. What is more, industrial pollution hides the natural magnetic properties of chernozems. In opposite, the studies at the sites under low anthropopression (mainly located in forests) allow for better insight into magnetic proper-ties arising during pedogenic processes, indirectly giving information about soil conditions. In the forest areas, the lowest values of soil magnetic susceptibility were measured. Additionally, the influence of pedogenic and lithogenic factors on forest soils is manifested in the results. Among the sites concerned, particular attention should be paid to the vicinity of the steel plant because of the agricultural land in the surroundings.

23 March 2018
Verified
Conference Paper
Open access
AWAnna Wojas
Anna Wojas
TGTeresa Grabowska
Teresa Grabowska
MMMateusz Mikołajczak
Mateusz Mikołajczak
The paper presents results of the study on relative secular variations of total magnetic intensity (TMI) of the geomagnetic field along the 700 km long profile crossing the area of Poland. Surveys were carried out at annual intervals between 1966 and 2016 (50 measurement series), in 31 survey sites (secular points) separated by about 22 km. The studied profile of the SW-NE direction, called Zgorzelec-Wiżajny (Z-W), crosses large parts of the main tectonic units of Europe, namely the Palaeozoic Platform of Central and Western Europe (PLZ) and the East European Craton (EEC), connected by the Teisseyre-Tornquist Zone (TTZ). Using the original methodology of analysis of measured data, reduced to the values of geomagnetic field recorded at the Central Geophysical Observatory in Belsk, the relative secular variations of TMI with the magnetic anomalies (ΔT) and the terrestrial heat flow density (Q) were graphically presented.