Monitoring of heat transmission from buildings into geological environment and evaluation of soil deformation consequences in foundation engineering

In engineering geology a number of factors affecting foundation conditions are taken into consideration during engineering-geological investigations. This article deals with the factor of heat sourced from a structure (brick kiln) as a restrictive factor in foundation engineering in clay soils and introduces a documentation of soil deformation observations as an impact of the heat transmission into the geological environment. It was carried out in Southern Moravia in the Czech Republic, where the dominant foundation soils are Neogeneous clays where differential settlements of a tunnel kiln structure occurred as a result of ignoring the boundary conditions of temperature changes in the soil environment. The brick kilns caused heterogeneous spatial changes in the subsoil temperatures. This consequently resulted in differential settlements due to temperature changes originating from the kilns. The differential settlements reached as much as 150 mm. The major objective of the article is to highlight the importance of the heat transmission from buildings into the geological environment as a factor which should be considered in engineering geology and its application in planning. A new procedure for reducing or elimination of ground movements sourced from underlying clayey soils depending on the heat changes was also suggested in this context.     

Environmental impact of blasting at Drenovac limestone quarry (Serbia)

In present paper, the blast-induced ground motion and its effect on the neighboring structures are analyzed at the limestone quarry "Drenovac" in central part of Serbia. Ground motion is examined by means of existing conventional predictors, with scaled distance as a main influential parameter, which gave satisfying prediction accuracy (R > 0.8), except in the case of Ambraseys–Hendron predictor. In the next step of the analysis, a feed-forward three-layer back-propagation neural network is developed, with three input units (total charge, maximum charge per delay and distance from explosive charge to monitoring point) and only one output unit (peak particle velocity). The network is tested for the cases with different number of hidden nodes. The obtained results indicate that the model with six hidden nodes gives reasonable predictive precision (R ≈ 0.9), but with much lower values of mean-squared error in comparison to conventional predictors. In order to predict the influence level to the neighboring buildings, recorded peak particle velocities and frequency values were evaluated according to United States Bureau of Mines, USSR standard, German DIN4150, Australian standard, Indian DMGS circular 7 and Chinese safety regulations for blasting. Using the best conventional predictor, the relationship between the allowable amount of explosive and distance from explosive charge is determined for every vibration standard. Furthermore, the effect of air-blast overpressure is analyzed according to domestic regulations, with construction of a blasting chart for the permissible amount of explosive as a function of distance, for the allowable value of air-blast overpressure (200 Pa). The performed analysis indicates only small number of recordings above the upper allowable limit according to DIN4150 and DMGS standard, while, for all other vibration codes the registered values of ground velocity are within the permissible limits. As for the air-blast overpressure, no damage is expected to occur.     

Late cretaceous radiolarians and age of flyschoid sediments in the Struganik section (Western Serbia)

The succession of radiolarian assemblages in the Struganik section of western Serbia is described for the first time. The following radiolarian beds are defined in carbonate flyschoid sequences represented by thin-platy limestones with calcarenite and bentonite clay intercalations (from the base upward): Theocampe urna-Dictyomitra koslovae (presumably lower Santonian); Afens perapediensis-Clathropyrgus titthium (presumably uppermost lower Santonian-basal upper Santonian); Alievium gallowayi-Crucella espartoensis (upper Santonian). The examined assemblages are characterized by high taxonomic diversity. The upper Santonian Alievium gallowayi-Crucella espartoensis Assemblage exhibits significant similarity with the coeval radiolarian assemblage of the Crimean Mountains (Ukraine). Archaeocenosphaera (?) karamatai sp. nov. is described.     

Forcing mechanisms of a heavy precipitation event in the southeastern Adriatic area

The aim of this study was to identify the main mesoscale features and mechanisms responsible for the generation of an extreme precipitation event as a contribution to improving the modelling of processes that produce HPEs. The event occurred during the morning hours on 22 November 2010 over the Dubrovnik coast in Croatia and the hinterland mountain range of the southern Dinaric Alps and caused severe flash floods and landslides and consequent interruption of traffic and electricity supply as well as other infrastructural damage. The analysis is geographically focused on the southern portion of the eastern Adriatic region, which is prone to relatively frequent heavy precipitation events that occur mostly in autumn. This area is one of the rainiest in Europe with expected annual amounts of precipitation greater than 5,000 mm in the mountainous hinterland. The mechanisms responsible for the formation of convection were analysed using synop measurements, satellite data and numerical experiments performed with the WRF model, which was set up at the convection-permitting resolution in the innermost domain. Satellite data were used to identify the precipitation systems and to estimate the intensity of the precipitation during the period of interest. The development of the precipitation system was connected to a strong large-scale ascent over the southern Italy and southern Adriatic due to the advection of warm air and cyclonic vorticity advection, which increases with height. The numerical simulations highlighted the essential role of a southerly low-level jet stream in the transport of warm and moist air towards the affected area. The convergence of two branches of low-level marine air favoured convection triggered over the coast and sea. Furthermore, numerical sensitivity experiments suggested that the orography of the Dinaric Alps plays an essential role in the precipitation maximum over the mountainous hinterland, but also that the orography was not the crucial factor in the heavy precipitation near Dubrovnik. This study highlights the need for a dense network of observations, especially radar measurements, to validate the simulated mechanisms and improve numerical forecasts via data assimilation.     

Preservation of diagenetic products of β-carotene in sedimentary rocks from the Lopare Basin (Bosnia and Herzegovina)

Sedimentary rocks from the saline formation of the Lopare Basin were investigated. Sediments contain a moderate amount of immature to marginally mature algal organic matter deposited under slightly reducing to anoxic and slightly saline to hypersaline conditions. Almost all of the samples contain β-carotane in a relatively high quantity, and in some, it represents the most abundant compound in the total distribution of hydrocarbons. The objective of the study was to determine the conditions that are favourable to precursors of β-carotene and/or the preservation of the carotenoid hydrocarbon skeleton. Moreover, the dominant transformation pathways of β-carotene under different redox and salinity conditions, which lead to the formation of aromatic carotenoids were defined.     

Vulnerability to natural disasters in Serbia: spatial and temporal comparison

The frequency of natural disasters and the extent of their consequences at a global level are constantly increasing. This trend is partially caused by increased population vulnerability, which implies the degree of population vulnerability due to high-magnitude natural processes. This paper presents an analysis of vulnerability to natural disaster in Serbia in the second half of the twentieth and the early twenty-first century. Vulnerability changes were traced on the basis of demographic–economic indicators derived from statistical data for local government units (municipalities) provided by the Statistical Office of the Republic of Serbia. Calculations were performed in the geographical information system environment. The results of the study show that spatial and temporal vulnerability variations are causally correlated with changes in the selected components. Significant rise of vulnerability is related to urban areas, while lower values are characteristic for other areas of Serbia; this is primarily a consequence of different population density.     

Photometric and spectrophotometric observations of Nova Delphini 1967

Photographic, photovisual and photoelectric (V) observations of Nova Delphini 1967 were made from August 8 to October 31 (Table I, Figure 1). Simultaneously spectrophotometric measurements of the continuum were made on objective prism exposures extending to November 26, and spectrophotometric gradients derived (Tables II and III; Figures 3, 4, and 5). The continuum of Nova near its flat maximum is close to that of an early-type star in contrast to late-type absorptionline spectrum.     

Controls on surface water chemistry in two lake‐watersheds in the Adirondack region of New York: differences in nitrogen solute sources and sinks

The southwestern Adirondack region of New York receives among the highest rates of atmospheric nitrogen (N) deposition in the USA. Atmospheric N deposition to sensitive ecosystems, like the Adirondacks, may increase the acidification of soils through losses of exchangeable nutrient cations, and the acidification of surface waters associated with enhanced mobility of nitrate (NO₃^?). However, watershed attributes, including surficial terrestrial characteristics, in‐lake processing, and geological settings, have been found to complicate the relationships between atmospheric N deposition and N drainage losses. We studied two lake‐watersheds in the southwestern Adirondacks, Grass Pond and Constable Pond, which are located in close proximity (～26 km) and receive similarly high N deposition, but have contrasting watershed attributes (e.g. wetland area, geological settings). Since the difference in the influence of N deposition was minimal, we were able to examine both within‐ and between‐watershed influences of land cover, the contribution of glacial till groundwater inputs, and in‐lake processes on surface water chemistry with particular emphasis on N solutes and dissolved organic carbon (DOC). Monthly samples at seven inlets and one outlet of each lake were collected from May to October in 1999 and 2000. The concentrations of NO₃^? were high at the Grass Pond inlets, especially at two inlets, and NO₃^? was the major N solute at the Grass Pond inlets. The concentrations of likely weathering products (i.e. dissolved Si, Ca²⁺, Mg²⁺, Na⁺) as well as acid neutralizing capacity and pH values, were also particularly high at those two Grass Pond inlets, suggesting a large contribution of groundwater inputs. Dissolved organic N (DON) was the major N solute at the Constable Pond inlets. The higher concentrations of DON and DOC at the Constable Pond inlets were attributed to a large wetland area in the watershed. The DOC/DON ratios were also higher at the Constable Pond inlets, possibly due to a larger proportion of coniferous forest area. Although DON and DOC were strongly related, the stronger relationship of the proportion of wetland area with DOC suggests that additional factors regulate DON. The aggregated representation of watershed physical features (i.e. elevation, watershed area, mean topographic index, hypsometric‐analysis index) was not clearly related to the lake N and DOC chemistry. Despite distinctive differences in inlet N chemistry, NO₃^? and DON concentrations at the outlets of the two lakes were similar. The lower DOC/DON ratios at the lake outlets and at the inlets having upstream ponds suggest the importance of N processing and organic N sources within the lakes. Although an inverse relationship between NO₃^? and DOC/DON has been suggested to be indicative of a N deposition gradient, the existence of this relationship for sites that receive similar atmospheric N deposition suggest that the relationship between NO₃^? and the DOC/DON ratio is derived from environmental and physical factors. Our results suggest that, despite similar wet N deposition at the two watershed sites, N solutes entering lakes were strongly affected by hydrology associated with groundwater contribution and the presence of wetlands, whereas N solutes leaving lakes were strongly influenced by in‐lake processing. Copyright © 2006 John Wiley & Sons, Ltd.     

A note on the thermal component of the equation of state in solids

A simple method for determining the thermal component of the EOS of solids under high pressure is proposed. Application to the interior of the Earth gives results in agreement with recent geophysical data.     

Observations of the Ushant tidal front in September 2007

The Ushant tidal front is the dominant feature of the summer season hydrological structure of the Iroise Sea. It separates tidally mixed coastal waters from thermally stratified open Celtic Sea waters. This article reports on observations made in September 2007 during two short cruises that took place aboard R/V “Côtes de la Manche”, and gives a general account of the physical structure of the front along one cross-frontal transect. The data set comprises data from a 4 month ADCP mooring, short CTD/fluorescence/nutrients transects, Lagrangian drifter trajectories, and HF radar surface current measurements. One finding is that the surface and bottom fronts, being affected by different dynamical influences, are not necessarily coincident in the vertical. This entails that the opposite density gradients located above and below the thermocline depth do not necessarily compensate, and can each be associated with a significant surface geostrophic expression. A second finding is that mixing effects bear a very strong influence on the thermal structure of the warm-water intrusions associated with frontal cyclonic eddies of the kind described by Pingree [1978. Cyclonic eddies and cross-frontal mixing. Journal of the Marine Biological Association of the United Kingdom 58 (4), 955–963].