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Application of electrical resistivity imaging (ERI) for the assessment of peat properties: a case study of the Całowanie Fen, Central Poland

Kowalczyk S., Żukowska K. A., Mendecki M. J., Łukasiak D.

Acta Geophysica

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2017

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Vol. 65, no. 1

223--235

EN

Complex studies were carried out to recognize the fen structure and peat properties in the Całowanie Fen area, belonging to the Natura 2000 network. The studies were conducted in two study areas that differ significantly in terms of peat thickness. Electrical resistivity imaging (ERI) was used to identify the properties of the peat and its substrate, such as thickness and electrical resistivity. Comparison of the field studies with the laboratory tests has shown that the ash content rises electrical resistivity in peat. In addition, the study has shown that the application of non-invasive geophysical methods in protected areas is justified. The fen, as a medium containing mostly water, was a proper test area for the ERI measurements.

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Comparison of site effect values obtained by HVSR and HVSRN methods for single-station measurements in Tarnówek, South-Western Poland

Mendecki M. J., Bieta B., Mateuszów M., Suszka P.

Contemporary Trends in Geoscience

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2016

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Vol. 5, iss. 1

18--27

EN

This study compares the HVSR technique (Horizontal to Vertical Spectral Ratio), based on seismic event records, and the HVSRN technique (Horizontal to Vertical Spectral Ratio of Noise) using seismic noise registrations. Both methods allow us to study the amplification phenomenon of a horizontal component of seismic waves when the waves reach loose sediments in subsurface layers. The seismic data were measured at a three-component single seismic station located in the village of Tarnówek, in the Legnica-Głogów Copper District. The results of the study demonstrate that average HVSRN and HVSR maxima can be distinguished: for periods approximately 3.78 s (H/V = 6.2) and 3.969 s (H/V = 8.98) respectively. The evaluated share of the Rayleigh wave component in the recorded values was β = 0.58 and it can be suggested that the Love wave share in surface motion was insignificant. The Love wave share remains unknown.

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Application of Multichannel Analysis of Surface Waves to S-Phase Wave Anisotropy Estimation

Stan-Kłeczek I., Mendecki M. J.

Acta Geophysica

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2016

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Vol. 64, no. 5

1593--1604

EN

The Multichannel Analysis of Surface Waves (MASW) is an increasingly used technique for recognition of a shallow geological structure and estimation of geotechnical parameters, e.g., S-wave velocity, layer density, layer thickness, shear modulus, estimated P-wave velocity, and estimated Poisson ratio. MASW surveys were carried out in two limestone quarries in the southern part of Poland. The experimental areas are characterised by a simple geological structure: consolidated Triassic limestone. Measurement profiles were arranged as a shapely six-pointed star. For each survey line, 12 geophones with 2-meter (Deposit 1) and 3-meter (Deposit 2) spacing were applied. The research allowed to compare P- and S-wave velocity changes with the main crack systems in the studied rock masses.

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Application of DOI index to analysis of selected examples of resistivity imaging models in Quaternary sediments

Glazer M, Mendecki M J, Mycka M

Studia Quaternaria

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2014

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Vol. 31, Nr 2

109--114

EN

Interpretation of resistivity cross sections may be in many cases unreliable due to the presence of artifacts left by the inversion process. One way to avoid erroneous conclusions about geological structure is creation of Depth of Investigation (DOI) index maps, which describe durability of prepared model with respect to variable parameters of inversion. To assess the usefulness of this interpretation methodology in resistivity imaging method over quaternary sediments, it has been used to one synthetic data set and three investigation sites. Two of the study areas were placed in the Upper Silesian Industrial District region: Bytom–Karb, Chorzów–Chorzów Stary; and one in the Southern Pomeranian Lake District across Piława River Valley. Basing on the available geological information the results show high utility of DOI index in analysis of received resistivity models, on which areas poorly constrained by data has been designated.

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Determination of the resonance frequency - thickness relation based on the ambient seismic noise records from Upper Silesia Coal Basin

Mendecki M. J., Bieta B., Mycka M.

Contemporary Trends in Geoscience

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2014

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Vol. 3, iss. 1

41--51

EN

In this paper the Horizontal-to-Vertical Spectral Ratio (HVSR) method and seismic data were applied to evaluate the resonance frequency – thickness relation. The HVSR method was used to estimate the parameters of site effects: amplification and resonance frequency from seismic noise records. The seismic noise was generated by artificial source occurring in Upper Silesia Coal Basin (UBSC), Poland, such as: traffic, industry, coal plants etc. The survey points were located near the Faculty of Earth Sciences in Sosnowiec, Bytom and Chorzow. Based on Albarello’s statistical test the observed H/V maxima was confirmed or rejected. Resonance frequencies were compared with available thicknesses of soft layer obtained by seismic survey (Mendecki 2012). Finally, the estimated resonance frequency – thickness relation for UBSC area showed quite similar power function coefficients as those obtained by other authors.

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Preliminary results of fractal analysis of the poligonal survey from cave: case study of Małołączniak area (Tatra Mts.)

Szczygieł J., Mendecki M. J.

Contemporary Trends in Geoscience

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2013

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Vol. 2, iss. 1

95--100

EN

Traverses (polygons) from two caves have been tested: Wielka Śnieżna Cave System (2858 vectors) and Śnieżna Studnia cave (742). The box counting technique was applied to evaluate the fractal analysis of spatial orientation of traverses. The polygonal survey of Wielka Śnieżna Cave, Śnieżna Studnia and both caves merged together have a fractal geometry. It may be concluded that these caves are close to the full recognition of passages forming by a hydrological system and they could have close relation with geological structures. The usual explanation of fractal dimension D higher than 1 indicates that caves with such dimension fill more space than those with ideal dimension of 1.00 (for example a straight line), and the geological constraints limit the dimension to be lower than 2 (Verbovsek 2007). It may suggest that systems can be developped into more complicated passages in future. The fact that both caves merged together also have showed fractal geometry indicates that they are belonging to the same hydrological system. It was noticed that D-value of merged caves is slightly larger than individual cave. It can be explained by “occupying” more space in rock mass.

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An application of geoelectrical methods for contamination plume recognition in Urbanowice waste disposal

Mycka M., Mendecki M. J.

Contemporary Trends in Geoscience

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2013

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Vol. 2, iss. 1

42--47

EN

The purpose of this work was to detect groundwater pollution and to identify the conditions of soil and groundwater near the Urbanowice landfill site using geoelectrical measurements. Presented measurements are preliminary results from tested site and are beginning of continuous monitoring. Contamination outflows detected by resistivity and IP technique show a good correlation with available hydrological data. Contamination plume were found in Eastern part of survey profil.

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An inversion of Rayleigh waves dispersion curves as a tool to recognize the bedrock depth in Chorzów Stary, Poland

Mendecki M. J., Zuberek W.M., Hrehorowicz P., Jarek Sz.

Contemporary Trends in Geoscience

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2012

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Vol. 1, iss. 1

39--44

EN

Identification of a bedrock beneath soft cover is one of the most important task in engineering geology. The location of boundary-overburden information may be used by investors, builders and municipal authorities to design an infrastructure or land-use plans. In such issues the application of appropriate geophysical methods is useful. However, in urban zones and areas characterized by subsurface soft layer the usage of certain methods (eg.: seismic refraction) is not advisable. The passive method of Refraction Microtremor (ReMi) can fulfill its tasks in the relatively difficult urban environment. The vertical S-wave velocity profiles were carried out as a result of inversion of Rayleigh wave dispersion curves obtained from ReMi method. The change of S-wave velocities allowed to distinguish shallow geological layers in the area of Chorzów Stary. Preliminary measurements allowed to identify the Carboniferous bedrock at a depth of 14-18 m what has been confirmed by resistivity imaging. Furthermore, unconsolidated deposits are also recognized and the seismic results show a good correlation with the available geological information and resistivity imaging data.

PL

Rozpoznanie zalegania sztywnego podłoża pod warstwą luźnych osadów jest jednym z ważniejszych zagadnień w geologii inżynierskiej. Informacja o położeniu granicy podłożenadkład wykorzystana może zostać przez inwestorów, inżynierów budowlanych lub władze gmin do projektowania właściwych konstrukcji lub planowania zagospodarowania przestrzennego. W takich sytuacjach przydatne stają się rozwiązania jakie proponują właściwe metody geofizyczne. Jednakże w strefach zurbanizowanych oraz charakteryzujących się luźnymi warstwami przypowierzchniowymi zastosowanie niektórych metod (np.: sejsmiki refrakcyjnej) nie jest wskazane. Metoda refrakcji mikrodrgań ReMi (pasywna) spełnia swoje zadania w tych względnie trudnych warunkach. W wyniku inwersji krzywych dyspersyjnych fal Rayleigha otrzymano pionowe zmiany prędkości fali S, co pozwoliło na rozróżnienie warstw geologicznych. W rejonie Chorzowa Starego przeprowadzono wstępne pomiary, które pozwoliły na rozpoznanie zalegania podłoża karbońskiego na głębokości ok. 15 m. Wydzielone warstwy w strefie osadów luźnych wykazały także dobrą korelację z dostępną informacją geologiczną oraz pomiarami inwersyjnego obrazowania oporności.