Lattice expansion and ionic substitution in common pyroxenoids

A study of the behavior of the lattice constants of common pyroxenoids and pyroxenes, especially bustamites and rhodonites, reveals that calcium causes the lattices of pyroxenes and rhodonites to expand more anisotropically than those of bustamites or wollastonites. Thus, the chain silicates are characterized by two different types of expansion. In the second part of the paper an attempt is made to correlate the chemical compositions and unit cell parameters of bustamites and rhodonites using the data of 14 bustamites and 33 rhodonites, most of which were investigated in this work. In the case of bustamites, the chemical composition can be determined using the lattice parameters,b and d₁₀₀. In the case of rhodonites, the amount of calcium can be determined very accurately, and that of magnesium can be estimated to an accuracy of 3–4 mole-%.     

Comparing geophysical methods for talus slope investigations in the Turtmann valley (Swiss Alps)

Three geophysical methods, ground penetrating radar, 2D-resistivity and seismic refraction were applied to two landform complexes in a high-alpine valley in Switzerland to investigate their internal structure. Results of the different methods were analysed separately, before conclusions about sediment thickness and geomorphologic implications were drawn. The results from the three methods were compared to focus on the quality of the methods and their field utility, with respect to portability of equipment, required man-power and measurement time. In this study, ground penetrating radar and seismic refraction proved to be the most suitable with respect to the quality and resolution of the subsurface information and the level of field utility. Sediment thicknesses of 15 m on a rectilinear slope and more than 30 m on a talus cone have been measured; a backweathering rate of approximately 700 mm ka^− 1 was established. Furthermore, the radar delivered detailed internal sediment structure as well as interfaces between talus and rock glacier. The combined geophysical investigation produced a detailed image of the subsurface composition of the two landform complexes that enhance the understanding of the paraglacial landform evolution in this hanging valley.     

Bücher- und Zeitschriftenschau

Ohne Zusammenfassung     

Synthetic scenario generation of monthly streamflows conditioned to the El Niño–Southern Oscillation: application to operation planning of hydrothermal systems

Stochastic Environmental Research and Risk Assessment - The Brazilian Interconnected Power System is hydro dominated and characterized by large reservoirs presenting multi-year regulation...     

Using the SDIlight Approach in Teaching a Geoinformatics Master

ITC, the Faculty of Geo–Information Science and Earth Observation of the University of Twente, is an institute that aims at capacity building and institutional development, specifically in developing countries. In our Geoinformatics curriculum, we emphasise two principles. The first addresses the systematics of purposeful spatial data production and uptake into computerised systems; the second addresses the methodical construction of these computerised systems, applying principles of model – driven architecture, formal specification and transformational design of SDI nodes. The term Spatial Data Infrastructure (SDI) usually denotes large, complex systems, but its principles can also be applied in simple and cost–effective ways. This approach we have called SDI^light and it is of particular interest to our students that come from developing countries. We work with and build a software stack consisting of free and open source components. To achieve interoperability, we emphasise the use of open standards from the Open Geospatial Consortium and others. In this paper, we explain how our students apply the SDI^light approach in the GeoinformaticsMaster degree course. An important part of that course is a Case Study Application Building & Programming, in which students apply their knowledge in a ‘real–world’ project, with a focus on geo–information engineering skills. We conclude with a section that evaluates the effectiveness of using the SDI^light concept in teaching our Geoinformatics Master, and on the more general applicability of the methodology.     

Stability Dependence of the Eddy-Accumulation Coefficients for Momentum and Scalars

From a set of turbulence data collected with a three-axis sonic anemometer/thermometer and described in a companion paper, we simulate the eddy-accumulation process for sensible heat and momentum fluxes. The resulting eddy-accumulation coefficient for momentum clearly depends on surface-layer stability; at neutral stability, its value is 0.63. On supplementing the scalar eddy-accumulation coefficients that we derive from our sensible heat flux data with values of sensible and latent heat flux coefficients reported by Businger and Oncley, we also find that scalar eddy-accumulation coefficients depend on stability, though more weakly than does the momentum coefficient. The coefficients for sensible and latent heat show no significant difference; we, thus, fit them with one function of stability whose value is 0.52 for neutral stratification.     

Einfache Erzeugung der Höhendifferenzgleiche

Summary A simple modus of generating the locus of equal differences of altitude upon the sphere is shown. By means of it, an orthographio projection of this locus is constructed.