In this paper we examine ways to predict the distribution of siliceous rock in Europe, using a Bayesian technique known as ‘Weights-of-Evidence’. We use the technique to classify bedrock geological formations in terms of their likelihood of yielding tool-quality lithic raw materials, and we use the results to reexamine possible causes of a west–east cline in maximum lithic raw material transfer...

We examined the Csalóka Spring, which has the highest radon concentration in the Sopron Mountains (West Hungary) (, yearly average of 227 ± 10 Bq L(-1)). The main rock types here are gneiss and micaschist, formed from metamorphism of former granitic and clastic sedimentary rocks respectively. The aim of the study was to find a likely source of the high radon concentration in water. During two p...

The effects of horizontal stress transmission on the transient evolution of non-linear viscous bodies having aspects ratios similar to active alpine rock glaciers is investigated. This is done through a comparison between a shallow-ice model, which predicts material flux to be a local function of thickness and slope, and a finite-element model, which solves the full Stokes problem. For length-t...

This work evaluates the diet and the reproductive cycle of Tropidurus torquatus in relation to seasonality in a rock outcrop formations in a remaining area of Atlantic Rainforest. The data indicate that the lizards feed mainly on arthropods and plant material. The female reproductive activity varies between seasons, while males contain spermatozoids throughout the year. The minimum body size at...

Nowadays there is a large number of tunneling projects in progress, mainly in Europe, both for roads and transport supplies. Performance prediction of tunnel boring machines (TBM) and the determination of some design parameters have become crucial, as they are critical elements in planning a project of mechanical excavation. In this paper we use the Discrete Element Method (DEM) to build models...

Recent work at the Underground Research Laboratory of Atomic Energy of Canada Limited in Pinawa, Manitoba, has shown that high compressive stresses near the tunnel face significantly contribute to the loss of strength, and eventual failure of the rock, through stress-induced brittle fracturing. A program of laboratory testing has been undertaken to investigate the effects of brittle fracture on...

ABSTRACT: This study provides an analysis of the influence of underground CO2 storage on the effective stress field in a representative geological formation. Large scale finite element models are used to describe the injection process. For high injection rates, different material degradation mechanisms may be activated depending on initial conditions. The case of rock fracturing due to tensile ...

Becker et al. (1) presented geochemical evidence that suggests that the largest mass extinction in Earth history, at the PermianTriassic boundary (PTB) 250 million years ago (Ma), coincided with an extraterrestrial impact comparable in size to the one that likely caused the end-Cretaceous extinctions 65 Ma (2). Although Becker et al. analyzed material from sections in Hungary, Japan, and China,...

About 125 130 million years ago South America began to separate from Africa and as the continents drifted apart, an extensive rift valley was formed, containing large lakes with abundant organic material that had washed off the adjacent highlands. In Angola, these sediments are known as the Bucomazi formation, an exceedingly rich oil and gas source rock. The rift valleys are similar to the pres...

Stylolites are rough dissolution pairs of surfaces that are generated by stress induced solution. These irregular structures can be found in various rock types and are mainly filled with fine-grained insoluble material. Stylolites are known to represent self-affine structures that have characteristic statistical properties (Schmittbuhl et al., 2004). We therefore investigate the scaling behavio...