An adaptable radio-controlled measuring system for oceanographic research in shallow water

The scientific objective of the system presented in this paper is to conduct in situ measurements of environmental parameters and to support several marine in situ experiments which are carried out in order to investigate the interaction between the sea and the sea bottom in shallow-water ecosystems. Automated in situ measurements are carried out by means of the radio-controlled data acquisition and control system "OBS" which is mounted on an unattended platform in the western Baltic. The shore station, at a distance of about 25 km, is located at the Institute of Applied Physics of Kiel University and is equipped with a central computer for real-time data retrieval and remote programming. Part of the OBS system is a vertical scanning profiling system which provides measurements of temperature, electrical conductivity, turbidity, scalar irradiance, downwelling and upwelling irradiance, pH, and dissolved oxygen in a water column of about 10-m depth. The vertical resolution is 10 cm. Profiling depth range was automatically determined from the shore by means of an adjustable upper depth limit, in order to protect the probes from surface waves. The research conducted here requires simultaneous measurements of various environmental parameters. This is done by about 20-30 fixed probes mounted on the platform in the air and in the water as well on the sea bottom in the neighborhood of the platform. The radio-controlled data acquisition system serves all probes and samples the sensors repeatedly in time.     

Employment generation in earth sciences through broad-basing of geoscience

Geoscience instruction in India is facing a serious crisis-instances are known of well-established university geology departments with more than a score of senior teachers having just a couple of M.Sc. students. This profound lack of demand for geoscience studies is a direct consequence of the paucity of employment opportunities for tradition-ally-trained geoscience graduates which     

Contemporary Tectonic Movements of the Western Caucasus and the Ciscaucasia Based on Satellite-Geodetic Observations

Geotectonics - The paper presents the velocity field of the Western Caucasus and Ciscaucasia based on GNSS observations. In the ITRF2014 reference frame, this field shows the coordinated movement...     

Electrical resistivity tomography study of Taal volcano hydrothermal system, Philippines

Taal volcano (311?m in altitude) is located in The Philippines (14°N, 121°E) and since 1572 has erupted 33 times, causing more than 2,000 casualties during the most violent eruptions. In March 2010, the shallow structures in areas where present-day surface activity takes place were investigated by DC resistivity surveys. Electrical resistivity tomography (ERT) lines were performed above the two identified hydrothermal areas located on the northern flank of the volcano and in the Main Crater, respectively. Due to rough topography, deep valleys, and dense vegetation, most measurements were collected using a remote method based on a laboratory-made equipment. This allowed retrieval of information down to a depth of 250?m. ERTs results detail the outlines of the two geothermal fields defined by previous self-potential, CO₂ soil degassing, ground temperature, and magnetic mapping (Harada et al. Japan Acad Sci 81:261–266, 2005; Zlotnicki et al. Bull Volcanol 71:29–49, 2009a, Phys Chem Earth 34:294–408, 2009b). Hydrothermal fluids originate mainly from inside the northern part of the Main Crater at a depth greater than the bottom of the Crater Lake, and flow upward to the ground surface. Furthermore, water from the Main Crater Lake infiltrates inside the surrounding geological formations. The hydrothermal fluids, outlined by gas releases and high temperatures, cross the crater rim and interact with the northern geothermal field located outside the Main Crater.     

SEDIMENT MANAGEMENT IN HYDROELECTRIC PROJECTS

Withdrawal of water from a river into a canal involves the construction of a barrage or a dam across the river depending on whether the river is perennial or not. The design of the reservoir upstream of the dam and of the canal requires consideration of the sediment load carried by the river in case the river is sediment-laden. The basic equations concerning morphological changes in such rivers are discussed with particular reference to computation of reservoir sedimentation. The hydraulics of lined canals carrying wash load is examined from the point of view of limiting transport capacity and changes in frictional resistance. Lastly, the methods of design of sediment extraction devices like settling basins and vortex chambers are presented.     

A micro-mechanical investigation of the dynamic response and liquefaction of saturated granular soils

A coupled continuum-discrete hydromechanical model was utilized to analyze the meso-scale pore fluid flow and micro-scale solid phase deformation of saturated granular soils. The fluid motion was idealized using averaged Navier–Stokes equations and the discrete element method was employed to model the solid particles. Well established semi-empirical relationships were used to quantify the fluid–particle interactions. Numerical simulations were conducted to investigate the mechanisms of granular deposit liquefaction in the presence of a critical upward pore fluid flow as well as when subjected to a dynamic base excitation. The outcome of these simulations was consistent with experimental observations and revealed valuable information on the micro-mechanical characteristics of soil liquefaction and associated loss of stiffness and strength.