Lenka Thinova

• Czech Technical University in Prague

New research of two craters at Emmerting (No. 4 and No. 5), Germany, is presented. This paper should be the first part of two papers concerning presumed impact craters at Emmerting. The second paper will be about mineralogical/petrological, temperature and stress analyses. The enstatite-dominated meteoritic material, found in the crater No. 4 [Proc...

Depressions containing partially molten rocks were investigated in Quaternary pebbly sedi-ments in Alpine foreland in Bavaria, Germany. Ruins of limekilns from 18-19th centuries are abundant around Seeshaupt. They are usually associated with earthworks for fuel feeding and protection from wind. Depressions contain partially molten stones from furna...

Cesium is the heaviest stable alkali metal (with only one stable isotope – 133Cs) and it occurs mainly as a potassium-substituting cation. It is an important trace element in rocks typical for the Earth crust, and its content in biomass is also relatively high compared to those abiogenic elements which are little soluble. Low-cost analytical method...

Kráterem číslo 4 u Emmertingu v pozdně glaciální terase řeky Alz se podrobněji zabývali Rösler et al. (2006). Přímé důkazy o impaktu nenašli, v podstatě však ukázali, že neexistuje životaschopná alternativa. Nic na tom nemění ani pochopitelné námitky proti teorii považující tento kráter za součást dopadového pole s více než 100 dochovanými impaktní...

Some information about two impact craters at Emmerting (Germany), including the first meteorite fragment found. The text is in Czech.

In the present study, the CFD technique is applied to perform sensitivity analysis for simulation of Rn-222 dispersions in the area surrounding the Pribram shaft No. 15 -applying a sample geometry derived from the waste rock dump site (Brod, Czech Republic). The influence of meteorological conditions, seasonal variations in land cover properties, c...

We report the results of 3-years of Radon-222 monitoring in six show caves across Europe, selected with the feature of having only one, or no natural entrance, defined as dead-end caves. The caves are located in Spain, Slovakia, Slovenia, and Czechia. The consecutive monitoring was performed between January 2017 and January 2020. Continuous measure...

The present work aims to assess the effective doses from long-term continual radon monitoring in six European caves (Slovenia, Slovakia and the Czech Republic), including influencing environmental factors. Caves are important radiation protection subjects because of elevated radon activity concentration (~kBq/m3), mostly due to the low natural vent...

Continuous monitoring of natural gamma radiation in air has been carried out, during December 2014 – January 2018, with 1-min cyclic measurement in Prague, Czech Republic using a NaI(Tl) probe. The 214Bi/214Pb ratio as a tracer in rainwater has been investigated to study its variations related to both the ambient dose equivalent rate per hour and t...

Anomalies in the Radon activity concentration time series recorded in five European caves (Czech Republic, Slovakia, Slovenia) are detected using three hybrid methods: (1) multiple linear regression and autoregressive integrated moving average statistical methods, (2) Empirical Mode Decomposition with Support Vector Regression techniques and (3) th...

The present work concerns a detailed analysis of Radon time series to differentiate endogenous from exogenous phenomena which provide anomalous signals. Two-year data from two sites in Czech Republic and in Italy are analyzed in order to contribute to the prevention of natural hazards. A new hybrid forecasting method is implemented and tuned for th...

Anomalies in the radon (222Rn) releases in underground environments are one of the phenomena that can be observed before earthquake occurrence. Continuous measurements of radon activity concentration, and of meteorological parameters that influence the gas emission, were performed in three Slovak and Czech caves during 1-y period (1 July 2016-30 Ju...

The analysis of the Earth's rotation rate time series, from January 1,2012 till December 31,2017, is performed using two different time series analysis methods, both based on signal decomposition joined with forecasting approach. Anomalies in the time series are detected making the comparison between the raw signal and the forecasting one at the 95...

In the year 2010 a continual radon measurement was established at Mladeč Caves in the Czech Republic using a continual radon monitor RADIM3A. In order to model radon time series in the years 2010-15, the Box-Jenkins Methodology, often used in econometrics, was applied. Because of the behavior of radon concentrations (RCs), a seasonal integrated, au...

This paper provides summary of the 8th Conference on Protection against Radon at Home and at Work and 13th Workshop on the Geological Aspects of Radon Risk Mapping held in September 2016 in Prague, Czech Republic.

There are ~7000 mining waste storage facilities including waste rock dumps in the Czech Republic. One of the radiation protection present subjects is a health impact estimation of the huge mass of material in waste rock dumps left after uranium mining. In this document are presented selected results of waste rock dump long-term monitoring in the ar...

Radioactive aerosol particles represent a serious risk for people facing the consequences of nuclear accident of any kind. The first responders to emergency situation need to be protected by personal protective equipment which includes radiation protection suit supplemented with gas mask. The purpose of this work is to estimate the dose to the orga...

Measurements of temperatures, CO2 concentrations and radon levels were performed within the study of microclimatic changes in the Arnoldka and Čeřinka caves, located at Paní hora Hill in the Bohemian Karst. The first stage of temperature measurements was carried out at 5 locations (3 in Arnoldka and 2 in Čeřinka) using automated temperature counter...

Characteristics of radon transport in porous media were studied through both in situ and lab-scale measurements. In situ measurements of radon activity concentration, together with soil thoron and carbon dioxide efflux, were carried out on Mt. Etna volcano. More detailed information on radon transport mechanisms has been obtained from laboratory me...

This paper focuses on the measurement and assessment of absorbed doses of radiation in caves of the Czech Republic, some of which exhibit high activity concentration of radon in air. Presented is an analysis and recommendations based on measurement results obtained in the underground caves over the past 12 y. The most important results for cave env...

The complex radiological study of the basin of sludge from the uranium ore mining and preprocessing was done. Air kerma rates (including its spectral analysis) at the reference height of 1 m above ground over the whole area were measured and radiation fields mapped during two measuring campaigns (years 2009 and 2014). K, U and Th concentrations in...

Unfolding technique makes it possible to reconstruct the incident photon spectra from the spectra, measured by the scintillation spectrometer and calculate dosimetric quantities of the measured photon fields. MC simulation of the detection system matrices and used unfolding method are presented as well as examples of the experimental spectra analys...

SPECIAL ISSUE ON THE "8TH INTERNATIONAL CONFERENCE ON HIGH LEVELS OF NATURAL RADIATION AND RADON AREAS" INCLUDING PEER REVIEWED PAPERS OF THE CONFERENCE

Tectonic instability may be measured directly using extensometers installed across active faults or it may be indicated by anomalous natural gas concentrations in the vicinity of active faults. This paper presents the results of fault displacement monitoring at two sites in the Bohemian Massif and Western Carpathians. These data have been supplemen...

Although there are many methods for investigating tectonic structures, many faults remain hidden, and they can endanger the life and property of people living along them. The slopes of volcanoes are covered with such hidden faults, near which strong earthquakes and gas releases can appear. Revealing hidden faults can therefore contribute significan...

The radon concentration in underground workplaces may reach tens of thousands of Bq m−3. A simple MCNPXTM Monte Carlo (MC) model of a cave was developed to estimate the influence of radon on the in situ gamma spectrometry results in various geometries and radon concentrations. The detector total count rate was obtained as the sum of the individual...

Deformation of the Earth’s lithosphere involves the response of a brittle crust overlying a ductile substrate. It is widely recognised that the nearly ubiquitous presence of discontinuities in the brittle crust ensures that the mechanical behaviour of a rock mass is different to that of most engineering materials. These discontinuities are major co...

Water-rich glass with radioactive inclusions was fabricated to mimic very slow radiochemical processes in natural minerals and rocks (and potentially in artificial silicate materials, e.g. in radioactive waste disposal). A mixture of sodium silicate (Na2SiO3.5 H2O) and uraninite (~UO2) was added to molten soda-lime silicate glass. The uraninite pow...

The project focused on classifying the level of irradiation from natural ionising radiation sources for workers in publicly accessible caves and in caves used for speleotherapy, with applicability to other underground workplace. A correct and accurate procedure (and calculation) is defined for determining the effective dose that workers are exposed...

It is well known that there are great variations in radon concentrations in the soil gas on building sites. The concentration may sometimes vary by more than two orders of magnitude. The tectonic structure of the bedrock is one of the factors that influence the intensity of the radon outflow. The simple ARES geophysical method [automatic resistivit...

In recent years, many underground spaces such as caves and deep mines have been used to monitor geodynamic activity in the Western Carpathians and Bohemian Massif. In addition, long-term radon gas monitoring has also being undertaken in three of the caves. The observed radon concentrations have shown diurnal, seasonal and yearly variations. A signi...

In-situ gamma spectrometry can be used for monitoring and determining natural and man-made radionuclide concentrations in the environment. The low detection limit of potential contaminants depends on the natural background variations, including variations in the atmospheric concentrations of radon and its decay products. The scintillation spectrome...

Measurement of the radon concentration has been performed in the Bozkov dolomite cave since 2002. Radon concentration was obtained by two means: continuous measurement by a Radim3 monitor at 30 min intervals and a 6 month average by LR115 solid-state nuclear track detector (SSNTD) in a diffusion chamber placed at 8 points along the cave tour path....

Most of radon and other environmental measurements were carried out in connection with research focused on improvement of radon dose assessment in the underground workplaces in the Czech Republic. The following methods are very useful for the detection of radon sources: air flow measurement; continual and short volume activity of radon and its prog...

A widely discussed question is how much a nuclear power plant really contributes to irradiation of the people living in its vicinity. A number of laboratory and in situ measurements were performed in the area surrounding NPP Temelin, on the basis of which we can specify the irradiation of this area from various sources. The evaluation includes the...

The method for depth-related radionuclide distribution was evolved for approximate determination of the spatial lay-out of radionuclides in materials. The method is based on different attenuation coefficients for various energies of gamma radiation. For each material, the attenuation coefficient decreases with rising energy of radiation. It is ther...

Changes in the ecosystem occur naturally, however, can also be due to man's activity. The unique ecosystem monitoring based on studying contamination of the bioindicators by man-made radionuclides has been providing data from the area of nuclear power plant (NPP) Temelin (CR) using laboratory gamma spectrometry for past 8 years. The increase in rad...

According to recommended approach there are six (from total of twelve) open-to-public caves in Czech Republic, reaching near to an effective lung-dose of 6mSv/year. A conservative approach for estimating the potential effective lung-dose in caves (or underground) is based on two season's measurements, using solid state alpha track detector (Kodak i...

In monitoring the impact of nuclear facilities operation on ecosystem, it is necessary to consider, what part of biota irradiation can be caused by an artificial source. For the estimation of an effective dose from natural sources were used measurements of dosimetric and gamma spectrometric characteristics of photon fields, (performed in the area o...

The new RAMARN system for radon volume activity measurement was developed in 2003 and has been in use since then. RAMARN system consists of a plastic chamber that is conically cylindrical in shape and about 0.5 l in volume; a bare Kodak LR 115 is located on the bottom of this diffusion chamber. The size was chosen to avoid the influence of deposite...

The sources of gamma radiation inside buildings affected by earlier silver and uranium mining activities are discussed. Possibilities how to reduce gamma dose rates from building materials were studied on several houses located in the old mining town Jáchymov. Results of the efficiency analysis are presented. Experience obtained up to now indicates...

The dose from radon and its progeny remains a frequently discussed problem. ICRP 65 provides a commonly used methodology to calculate the dose from radon. Our work focuses on a cave environment and on assessing the doses in public open caves. The differences in conditions (aerosol size distribution, humidity, radon and its progeny ratio, etc.) are...

It is generally not possible to correctly determine the long and short term impact of human activity upon the environment, without thorough processing of data, obtained through monitoring. It was confirmed that such impact on the environment must be monitored over a long time period. The data obtained must be of high quality, an attribute assured b...

The characteristic of the thin plate (Ø38x0.25mm) of scintillation detectors YAP:Ce (YAlO3 doped Ce) and YAG (Y3Al5O12 doped Ce) were tested by using the etalons of alpha, beta and gamma radiation with low energies (241Am, 90Sr, 55Fe...) and a standard 222Rn. Those detectors have been developed in Crytur Ltd. For the measurement was used a speciall...

The (bio)monitoring in the neighborhood of Nuclear Power Plant (NPP) Temelin started in the year 2000—1 year before the initial power plant operation. In the years 2000, 2002, and 2004, the spectrometry characteristics of photon-spectra measurement were included in biomonitoring. The area of interest contained 29 sampled locations along eight radia...

Conservative methodology for estimation of a potential dose in caves employs solid state alpha track detectors. Obtained data are converted into annual effective dose in agreement with the ICRP recommendations (using the “caves factor”). The more precisely determined dose value would have a significant impact on the radon remedies or on restricting...

With a focus on the detection of the Rn concentration in water in extreme conditions, the detection unit YAPMARE was developed by the company CRYTUR. The main part of the detection unit is a detection probe based on the Ø25×100 mm YAP:Ce detector. The measured water covers approximately 95% of the crystal surface (the detection volume is 12 ml). Me...

Personal dosimetry for underground workers mainly concerns measurement of the concentration of radon (and its daughters) and the correct application of the data in dose calculation, using a biokinetic model for lung dosimetry. A conservative approach for estimating the potential dose in caves (or underground) is based on solid state alpha track det...

X-ray fluorescence, using backscattering, was employed in the determination of sulfur content and ash content measurement in coal. The results of the methods are given to illustrate the differences between the chemical analysis and X-ray fluorescence method.

The mathematical processing (unfolding) of pulse height spectra from a scintillation detector helps to calculate the photon fluence rate energy distribution in a measured photon field. The data processing is based on the knowledge of detection system response function and directional dependence respectively. The experimental results of the photon f...

Measurement of the radon concentration has been performed in the Bozkov dolomite cave since 2002. Radon concentration was obtained by two means: continuous measurement by Radim3 monitor in 30-minute interval and 6-month average by LR115 SSNTD in the diffusion chamber placed at 8 points along the cave tour route. The radon concentration shows diurna...

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