Authors:Bo-chao Xu, W. Burnett, Derek Lane-Smith, and Zhi-gang Yu
Measurements of 222Rn (“radon”) in the environment are important in the geosciences and radiation-protection fields. We demonstrate here a simple
laboratory-based calibration system to evaluate the efficiency of radon detectors with a reproducibility of about ±2%. The
system uses a closed-loop air circulation design with 226Ra adsorbed onto MnO2-impregnated fiber as a radon source. Two RAD7 radon detectors (Durridge Co., Inc.) that were precisely calibrated at Durridge’s
in-house calibration facility are used as secondary standards. By parallel analysis of the radon-enriched air within the closed
loop, the test RAD7s are assigned a calibration coefficient to be applied to future measurements. We also performed a side-by-side
intercomparison with two RAD7s in a high-radon natural environmental setting (limestone cave in Florida) that produced comparable
A new closed rock sward association (
Erdős et Morschhauser, ass. nova.) has been found and described in the Villány Mts (SW Hungary). This community lives in northern expositions, near the ridge or the plateau. Bedrock is limestone and dolomite. In the association dominated by the grasses
, an unusual mixing of species can be encountered: species of the mesophilous forests, of the karst shrub-forests and of the xerophilous grasslands and rock swards occur together in this community. Description of the new community as a distinct association is supported by the PCoA ordination and the differential species. Ecological properties of the community were characterised by using ecological indicator values. This analysis also shows the dual character of the association. We analysed the new association by computing the spectra of the social behaviour types. The extraordinarily great amount of the disturbance tolerants is probably a consequence of the former grazing pressure or some other disturbance.
The clay mineral
composition of four brown forest soil profiles (Luvisols) developed on
different parent rocks was studied in detail to determine the major clay
mineral alteration processes. In the studied profiles a siltstone bedrock
weathered to chlorite/vermiculite and vermiculite in a less developed, shallow
soil profile, while the major product of soil formation in a clayey,
well-developed deep soil is a typical soil montmorillonite with heterogeneous
charge distribution. The most possible pathway of clay alteration is illite
smectitization via charge reduction, and considerable degradation of smectite
in the soil formed on limestone. On the contrary, weathering of andesite parent
rock involves the formation of low charged smectite altering to high charged vermiculite
this research, thermal characterization and kinetics of Karakus crude oil
in the presence of limestone matrix is investigated. Thermogravimetry (TG/DTG)
is used to characterize the crude oil in the temperature range of 20-900C,
at 10C min -1 heating rate using air
flow rate of 20 mL min -1. In combustion
with air, three distinct reaction regions were identified known as low temperature
oxidation (LTO), fuel deposition (FD) and high temperature oxidation (HTO).
Five different kinetic methods used to analyze the TG/DTG data to identify
reaction parameters as activation energy and Arrhenius constant. On the other
hand different f(α) models from literature
were also applied to make comparison. It was observed that high temperature
oxidation temperature (HTO) activation energy of Karakus crude oil is varied
between 54.1 and 86.1 kJ mol -1, while low
temperature oxidation temperature (LTO) is varied between 6.9 and 8.9 kJ mol -1.
The karstic bauxites of Mt. Grebnik, Kosovo, represent a unique deposit of the diasporic bauxites of Upper Cretaceous age in the former Yugoslavia. They are typically transitional between ferruginous bauxites and karstic Ni-Fe ores. Bauxites originated from surrounding Cretaceous weathering crusts on ultramafic rocks and on shale of the diabase-chert formation. Chemical and trace element analyses of the bauxite samples collected along a vertical profile of a typical deposit are presented and discussed. Trace element patterns, including REE and Ni, are typical for karstic bauxites formed in situ, during bauxitization of argillaceous material accumulated in a karstic depression. In connection with this, a progressive enrichment of the REE and Ni toward the bottom of the deposit is well pronounced, with formation of authigenic REE mineral, synchysite-(Nd), and Ni-bearing chlorite on the contact with the footwall limestone.
At the northeastern part of Transdanubia, connected to the karst-water system of the Gerecse Mts, travertine pools were formed in several localities, at different times and at various altitudes. Quarrying of the travertine is documented since the Bronze Age. The hand-operated quarries are known to have also functioned during the Middle Ages. Several relics of architecture and sculpture from the Roman province of Pannonia and Medieval Hungary were made of this material, specifically from the quarries of the study area. Exploitation of the limestone opened the large, vertically-walled pools preserving the settlements of Paleolithic people in the loose sediments and the travertine cover: at Vértesszõlõs, remains of Homo erectus, and at Tata, habitations of Homo sapiens neanderthalensis were found in the travertine. Collaboration between geoscientists and archeologists could, apart from identifying the sources of worked travertine, also result in the discovery of new archeological sites.
Authors:M. Carmo Freitas, L. Moens, P. De Paepe, and J. Seabra E Barros
A 7 kg stone of a Carrara marble was reduced to grains smaller than 100 m, mixed and homogeneized in order to prepare a marble reference material. The homogeneity was tested for 16 elements by instrumental neutron activation analysis (INAA). Through a one-way analysis of variance based on several analyses of each of 15 bottles and within the same bottle, it was concluded that the inter-bottle heterogeneity is not greater than the intra-bottle heterogeneity. Results on the concentration of major and trace elements in the marble reference material, obtained by different laboratories and different techniques, are given. The limestone certified reference material KALKSTEIN KH was used to evaluate measurement accuracy, to intercalibrate laboratories, and to provide compatibility of measurement data.
Authors:A. Navas, D. Walling, T. Quine, J. Machín, J. Soto, S. Domenech, and M. López-Vicente
The extent of soil erosion in some Spanish semiarid regions has caused great concern regarding the sustainability of soil
resources. Accelerated soil erosion, particularly in some Mediterranean areas, is likely to be one of the main environmental
problems associated with climate change. Fallout 137Cs has been shown to provide a reliable basis for assessing soil erosion rates in different environments around the world.
However, existing information concerning the spatial variation of 137Cs inventories at reference sites has identified a need for further investigation of the factors affecting their spatial variability
in semiarid environments, where stony and skeletal soils are predominant. Reference sites at three locations in the central
Ebro valley were selected to investigate the 137Cs content of several grain size fractions. Each site included both natural vegetated conditions and cultivated land and the
three sites were characterized by different values of mean annual rainfall. The results obtained demonstrate the influence
of lithology, land use and climate on the spatial variability of 137Cs inventories that increase from 1190, to 1500 and 1710 Bq·m−2 with increasing annual rainfall values from 300 to 500 mm at the study sites. The soils on marls at the Valareña site had
the highest proportion of 137Cs in the coarse fractions of cultivated soils (12%) in comparison with soils developed on limestones at Loma Negra (5%),
whereas no 137Cs content was found in the coarse fractions of soils on glacis-terrace materials at Peñaflor. The 137Cs reference inventories are higher in soils on marls and sands at cultivated locations at Valareña and Peñaflor, but have
similar values in soils at cultivated and uncultivated locations on limestones at Loma Negra. Therefore, in absence of level
undisturbed soils with natural vegetation cover, cultivated flat soils on hard rocks could provide reliable reference inventories.
Authors:Márton Bauer, Tivadar M. Tóth, Béla Raucsik, and István Garaguly
On page 32, in Fig. 2, the name “Cave Sediment” should read “Cave Limestone.”
On page 56, in lines 40 and 51, and on page 58, in line 50 in References section, the name “Geological and Institute of Hungary” should read “Geological Institute of
. Heinrich , R. Holzer , M. Laho , J. Rabeder , C. Uhlir , M. Unterwurzacher
2014 : Engineering geological properties of Leitha Limestone from historical quarries in Burgenland and Styria, Austria . – Engineering Geology , 176 , pp. 66