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Muon radiography is a technique that uses cosmic ray muons to image the interior of large scale geological structures. The muon absorption in matter is the most important parameter in cosmic ray muon radiography. Cosmic ray muon radiography is similar to X-ray radiography. The main aim in this survey is the simulation of the muon radiography for exploration of mines. So, the production source, tracking, and detection of cosmic ray muons were simulated by MCNPX code. For this purpose, the input data of the source card in MCNPX code were extracted from the muon energy spectrum at sea level. In addition, the other input data such as average density and thickness of layers that were used in this code are the measured data from Pabdana (Kerman, Iran) coal mines. The average thickness and density of these layers in the coal mines are from 2 to 4 m and 1.3 gr/cm3, respectively. To increase the spatial resolution, a detector was placed inside the mountain. The results indicated that using this approach, the layers with minimum thickness about 2.5 m can be identified. [ABSTRACT FROM AUTHOR]

An alternative approach to solving the inverse impedance problem of recovering the electrical properties of a layered medium from the direct-measurement data that is based on the statistical method is considered. The frequency dependences of the surface impedance measured in the very-long-, long-, and medium-wave bands have been interpreted. The results of solving the inverse problem for land- and water- area measurements performed in the high-latitude region in the eastern part of Russia are presented. [ABSTRACT FROM AUTHOR]

Rock glaciers are periglacial alpine landforms that are found in many locations worldwide. Whereas well-developed models of deformation are established for traditional alpine glaciers, rock glacier deformation is poorly understood. Geophysical data from Lone Peak Rock Glacier (LPRG), southwest Montana, USA, are paired with lidar bare-earth 1m digital elevation model (DEM) analysis to explore potential genetic relationships between internal composition, structure and regularly spaced arcuate transverse ridges expressed at the rock glacier surface. The internal composition of LPRG is heterogeneous, with frozen debris and clean ice overlain by an unconsolidated talus mantle. Upslopedipping, clearly distinguished reflectors in the ground-penetrating radar (GPR) longitudinal survey at LPRG correspond to transverse ridges. The spacing and slope of individual features at the surface and in the subsurface were measured and compared and are found to be similar. The structures observed at LPRG and other rock glaciers are similar to structures detected in glaciotectonically altered sediment, ice-cored moraines and other rock glacier settings. This finding suggests that transverse ridges on rock glaciers may be used as geomorphic indicators of internal deformation. This study contributes to the body of research on the application of GPR to rock glaciers, and is the first to directly pair and analyze individual surface topographic features with internal structures. [ABSTRACT FROM AUTHOR]

The article focuses on the efficiency of synchrotron phase-contrast hard X-ray imaging in the visualization of granular flows and landslide dynamics in granular piles. It states that polymethylmethacrylate (PMMA), silica, polystyrene and sands are set in underwater landslide to observe their sliding depth movements and granular displacements. It also presents the advantages of synchrotron phase-contrast hard X-ray imaging system in solving geophysical problems.

The performances of a shore-based high-frequency (HF) radar network deployed along the coast of the Venice lagoon (northern Adriatic Sea) are discussed based on a comparison with a single bottom-mounted ADCP deployed in the shallow-water area offshore of the lagoon for a 40-day period in August–September 2005. The analyses, carried out using currents representative of the first meter for the HF radars and 2.5 m for the ADCP, gave rms differences of radial currents in the range of 8.7–14.7 cm s−1 (correlation 0.37– 0.82) for the ideal pattern and 8.4–20.5 cm s−1 (correlation 0.14–0.84) for the measured pattern. Good correlation was found between surface current vectors and moored data (scalar correlation up to R = 0.83, vector correlation ρ = 0.78, veering angle 6°). Comparison metrics were improved for the low-passed currents. Angular offsets ranged between +6° and +11°. Differences depended primarily on the geophysical variability within the water column. Bearing offsets also contributed because they lead to comparisons with radial velocities at erroneous angular sectors. Radar performances were severely affected by strong northeasterly wind pulses in their early stages. An increased broadband noise, spread over the entire Doppler spectrum across all ranges to the antennas, masked the Bragg peaks and determined the loss in radar coverage, introducing gross underestimations of both radial velocities and total currents. [ABSTRACT FROM AUTHOR]

Abstract: In the framework of the management of karstic aquifers, geophysical reconnaissance can be used to locate conduits and caves, and to characterise the surrounding limestone matrix. Suitable characterisation of heterogeneities in the karstic environment is, however, challenging for ground-based geophysical methods. The present article describes the results, and evaluates the response and accuracy of combined geophysical measurements carried out at the Poumeyssen test site in France, involving electrical resistivity imaging (ERI), magnetic resonance sounding (MRS), “mise-à-la-masse” electrical mapping, and seismic tomography. This site provides the opportunity to study a relatively wide, shallow, water-filled conduit whose location and shape are known from topographic work carried out by cave divers. Seismic and MRS provided the exact location and width of the conduit, to within a few meters. The seismic and electrical data suggest that the limestone medium surrounding the conduit is not homogeneous. [Copyright &y& Elsevier]

Abstract: An X-ray multi-purpose dual-energy computer tomograph has been used to investigate a variety of objects of geological interest such as unconsolidated sediments (sand, silt, clay, mud) and/or metamorphic rock samples. By using an appropriate set of standard materials as well as a proper version of filtered back projection reconstruction algorithms, we have obtained for each studied sample two images, depicting with an error of 2 to 3% densities as well as the effective atomic number. In the case of unconsolidated sediment samples, the computer tomograph has been also used to obtain good quality radiographs, prior to obtaining the tomographic images of the cross-sectional area of interest. Both radiographs and computer axial tomography images had a spatial resolution of 0.4 to 0.5 mm. Digital radiographs as well as tomographic images of unconsolidated sediment samples show with clarity internal features such as grain sizes, laminae thickness and orientation, bioturbations, revoked materials or fragments of wood. Computer tomography analysis of rock samples reveals rheological features in the relationship with metamorphism and deformation, image contrast regarding density and atomic effective number of constituents, as well as significant correlations between physical parameters and internal structures or textures. [Copyright &y& Elsevier]

A unified approach to simulate both microwave radiometric and scatterometric observations over a sea surface based on the two-scale electromagnetic scattering model has been implemented. The simulations have been compared with empirically derived geophysical model functions (GMFs) for the purpose of tuning the electromagnetic forward model and the embedded sea surface characterization and wave spectrum. The comparison has concerned a large number of wind speeds, frequencies, and observation angles for both the passive and active cases. Two widely adopted literature spectra have been used as benchmarks. A new expression for the hydrodynamic modulation function has been developed too. The proposed new spectrum has allowed us to reproduce both the passive and active GMFs' behaviors fairly well, generally improving the agreement yielded by literature models, particularly for scatterometric simulations. [ABSTRACT FROM AUTHOR]

Abstract: The integration of structural analyses of outcrops, aerial photographs, satellite images, aeromagnetometric data, and digital terrain models can establish the structural framework and paleostress trends related to the evolution of Ponta Grossa Arch, one of the most important structures of the Paraná Basin in southern Brazil. In the study area, the central-northern region of Paraná State, Brazil, the arch crosses outcropping areas of the Pirambóia, Botucatu, and Serra Geral Formations (São Bento Group, Mesozoic). The Pirambóia and Botucatu Formations are composed of quartz sandstones and subordinated siltstones. The Serra Geral Formation comprises tholeiitic basalt lava flows and associated intrusive rocks. Descriptive and kinematic structural analyses reveal the imprint of two brittle deformation phases: D1, controlled by the activation of an extensional system of regional faults that represent a progressive deformation that generated discontinuous brittle structures and dike swarm emplacement along a NW–SE trend, and D2, which was controlled by a strike-slip (transtensional) deformation system, probably of Late Cretaceous–Tertiary age, responsible for important fault reactivation along dykes and deformation bands in sandstones. [Copyright &y& Elsevier]

An algorithm for solving the inverse problem of subsurface radiolocation using data from ground penetrating radar is presented in this paper. Experimental research was carried out using the geophysical device "Loza B" in field conditions; a part of airfield runway, located on the territory of Almaty region (Kazakhstan), was investigated. The conclusion concerning the reasons of occurrence of defects on the surface of the runway is given. [ABSTRACT FROM AUTHOR]

The article discusses two reports within the issue regarding geophysical research and how the use of a combination of high-resolution laser imaging and improved radiocarbon dating techniques is helping scientists better understand earthquake behavior. Topics include a brief overview of how paleoseismologists collect and use data of the stratigraphic and geormorphic history of deposits and landforms along fault lines and the interpretation of data by two research teams that raises questions about the fault behavior models that have been applied to the San Andreas Fault. Fault behavior models and what they are designed to measure, such as the amount of the relative displacement of points, called slips, on opposite sides of a fault, are also discussed.