Multi-stage evolution of xenotime–(Y) from Písek pegmatites,Czech Republic: an electron probe micro-analysis and Raman spectroscopy study     

E. Švecová  R. Čopjaková  Z. Losos  R. Škoda  L. Nasdala  J. Cícha 《Mineralogy and Petrology》2016,110(6):747-765

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Forecasting rock slope failure: how reliable and effective are warning systems?     

Martina?S?tteleEmail author  Michael?Krautblatter  Michael?Bründl  Daniel?Straub 《Landslides》2016,13(4):737-750

Warning systems are increasingly applied to reduce damage caused by different magnitudes of rockslides and rockfalls. In an integrated risk-management approach, the optimal risk mitigation strategy is identified by comparing the achieved effectiveness and cost; estimating the reliability of the warning system is the basis for such considerations. Here, we calculate the reliability and effectiveness of the warning system installed in Preonzo prior to a major rockfall in May 2012. “Reliability” is defined as the ability of the warning system to forecast the hazard event and to prevent damage. To be cost-effective, the warning system should forecast an event with a limited number of false alarms to avoid unnecessary costs for intervention measures. The analysis shows that to be reliable, warning systems should be designed as fail-safe constructions. They should incorporate components with low failure probabilities, high redundancy, have low warning thresholds, and additional control systems. In addition, the experts operating the warning system should have limited risk tolerance. In an additional hypothetical probabilistic analysis, we investigate the effect of the risk attitude of the decision makers and of the number of sensors on the probability of detecting the event and initiating a timely evacuation, as well as on the related intervention cost. The analysis demonstrates that quantitative assessments can support the identification of optimal warning system designs and decision criteria.  相似文献   

Geochemical characteristics of the Gacka River karstic springs (Dinaric karst,Croatia) with macroinvertebrate assemblages overview     

Natalija Matić  Krešimir Maldini  Damir Tomas  Renata Ćuk  Simana Milović  Igor Miklavčić  Siniša Širac 《Environmental Earth Sciences》2016,75(19):1308

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Geological mapping reveals the role of Early Jurassic rift architecture in the dispersal of calciturbidites: New insights from the Central and Northern Apennines     

Angelo Cipriani  Martina Caratelli  Massimo Santantonio 《Basin Research》2020,32(6):1485-1509

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Using Clustered Heat Maps in Mineral Exploration to Visualize Volcanic-Hosted Massive Sulfide Alteration and Mineralization     

Feltrin  Leonardo  Bertelli  Martina 《Natural Resources Research》2020,29(1):311-344

Natural Resources Research - This study proposes an extension of a visualization approach common in biochemistry (the clustered heat maps—CHMs) to geochemical data with the main objective of...  相似文献   

Towards new applications of underwater photogrammetry for investigating coral reef morphology and habitat complexity in the Myeik Archipelago,Myanmar     

Martina Anelli  Tommaso Julitta  Luca Fallati  Paolo Galli  Micol Rossini  Roberto Colombo 《国际地球制图》2019,34(5):459-472

Photogrammetry represents a non-destructive, cost-effective tool for coral reef monitoring, able to integrate traditional remote sensing techniques and support researchers’ work. However, its application to submerged habitats is still in early stage. We present new ways to employ Structure from Motion techniques to infer properties of reef habitats. In particular, we propose the use of Digital Surface Models and Digital Terrain Models for assessing coral colonies extension and height and discriminating between seabed and coral cover. Such information can be coupled with digital rugosity estimates to improve habitat characterization. DTM, DSM and orthophotos were derived and used to compute a series of metrics like coral morphologies, reef topography, coral cover and structural complexity. We show the potentialities offered by underwater photogrammetry and derived products to provide useful basic information for marine habitat mapping, opening the possibility to extend these methods for large-scale assessment and monitoring of coral reefs.  相似文献   

An anthropo-ecological approach to landscape use optimization     

Václav Škopek  Michael Bartoš 《GeoJournal》1988,17(3):365-372

A method of landscape evaluation based on the anthropo-ecological approach is worked out. The procedure consists of three stages, viz., general, special and optimization. Within the general stage, the structural arrangement of the landscape is evaluated by means of the concept of geo-ecological sites (GES), which are distributed into four zones (A, B, C, D) according to the degrees of their anthropic disturbance. The zoning performed makes it possible to select those geo-ecological sites where eco-critical relationships can be expected to appear; in order to eliminate such situations, transition zones are calculated for the geo-ecological sites concerned. The outcome of this approach is a proposal of a new structural arrangement of the geo-ecological sites, solving eco-critical situations and serving as a basis for the special and optimization stages of the anthropo-ecological method.  相似文献   

Stick-slip unstable shear failure as a source of high frequency elastic radiation     

J. Kozák  T. Lokajíček  J. Šílený  Reviewer V. Rudajev 《Studia Geophysica et Geodaetica》1989,33(4):322-337

Summary The results of laboratory measurements on square perspex models with a stress concentrator under uniaxial compression are presented. An attempt was made to interpret these results in order to determine the mutual relations between the mechanical parameters characterizing the treated models, including their focal zones, parameters of model loading, parameters of seismogenic displacement and parameters of radiated elastic pulses. Particular attention was given to the study of slip displacement, slip velocity, rupture velocity, nucleation points of rupture propagation, nucleation points of elastic radiation and to the frequency analysis of radiated pulses. Measurements of the displacement in the focal zone enabled us to determine the source function, to construct theoretical seismograms in a far field and to compare them with the real pulses from ultrasonic transducers located there. This allowed testing theoretical and experimental approaches to the study of how slip displacement, slip velocity and rupture velocity are related to the parameters of radiated pulses.  相似文献   

Measurement of a freezing nucleus content in a water sample — Evaluation of the method     

Martin Dubrovský  Otakar Školoud  Reviewer J. Kalvová 《Studia Geophysica et Geodaetica》1989,33(3):287-304

Summary A drop freezing technique applied in laboratory research to heterogeneous ice nucleation is described. The quality of the obtained experimental data is studied both theoretically and experimentally. Attention is focused on the range of measurable freezing nucleus concentration, the accuracy, the correctness and the reproducibility of the results. Some mechanisms which could influence the correctness of the method are discussed. No mechanism significantly influencing the measurements was found. It is concluded that the present experimental method is an effective method of measuring a freezing nucleus content in a water sample.

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Tidal deformations of viscoelastic body     

Jiří Trešl  Reviewer Z. Šimon 《Studia Geophysica et Geodaetica》1988,32(1):24-31

Summary The tidal deformations of a viscoelastic body are studied using the simple Kelvin-Voigt model. Expressions for the phase lag and amplitude change of the displacement vector are derived. The energy dissipation rate is calculated for the main disturbing bodies and for diurnal and semidiurnal tidal waves.

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