4-Dimensional Models of Deformation of the Earth's Crust and Earthquake Prediction

Traditionally, when creating 4-D models of elastic offsets in the Earth's crust, the data from geodesic and GPS monitoring of offsets on the ground surface, earthquake catalogs, monitoring of the water level and radon content in wells, sea level fluctuations, as well as gravitational and magnetic fields, etc., can be taken as bases for information. In essence, the reason for creating a 4-D model of slow elastic deformations is to approximate the process by a set of plane deformation solitons (solitary waves). The parameters of a set of deformation solitons are obtained by a two-stage inversion. First, the parameters of the model are determined in a kinematic way by the use of a modified simplification of the method. Then, a calibration of the amplitude characteristics of the model is carried out in terms of elastic dynamic offsets. Taking Ural, Northern Tianshan, Greece, and China as examples, models for these regions are created on the basis of seismological, geodesic, deformation, hydrogeological, and     

Building population mapping with aerial imagery and GIS data

Geospatial distribution of population at a scale of individual buildings is needed for analysis of people's interaction with their local socio-economic and physical environments. High resolution aerial images are capable of capturing urban complexities and considered as a potential source for mapping urban features at this fine scale. This paper studies population mapping for individual buildings by using aerial imagery and other geographic data. Building footprints and heights are first determined from aerial images, digital terrain and surface models. City zoning maps allow the classification of the buildings as residential and non-residential. The use of additional ancillary geographic data further filters residential utility buildings out of the residential area and identifies houses and apartments. In the final step, census block population, which is publicly available from the U.S. Census, is disaggregated and mapped to individual residential buildings. This paper proposes a modified building population mapping model that takes into account the effects of different types of residential buildings. Detailed steps are described that lead to the identification of residential buildings from imagery and other GIS data layers. Estimated building populations are evaluated per census block with reference to the known census records. This paper presents and evaluates the results of building population mapping in areas of West Lafayette, Lafayette, and Wea Township, all in the state of Indiana, USA.     

Hydrothermal and thermal treatment of natural clinoptilolite zeolite from Bigadiç, Turkey: An experimental study

The clinoptilolite rich zeolite from Bigadiç which was formed from alteration of volcanic glass were treated with acidic (HCl, H₃BO₃, H₃PO₄), alkaline (KOH, NaOH) solutions. Hydrothermally treated and untreated samples were heat treated at 400, 550 and 700°C. XRD, ICP-MS and N₂ gas adsorption were used for physicochemical characterization of zeolites. Considering the Si/Al > 4 and Na+K/Ca+Mg < 1 ratios, zeolite sample is included to earth alkali clinoptilolite class (Heu II) which is also revealed by thermal treatments. Since zeolite structure contains low alkalies it was at collapsed 550°C. The removal of oxide elements efficiency of acids and alkalies were in the order of HCl > H₃PO₄ > HBO₃ > KOH > NaOH. XRD analysis indicated that the structure of zeolite was not altered with acids and alkali treatments. The structure of zeolite treated with HCl and other acids started to deform at 400 and 550°C respectively. In treatment with HCl, Si/Al ratio increases with significant a decrease in K content which resulted in a decrease in the heat stability of zeolite. No change was observed in the structure and thermal stability of clinoptilolite after alkali treatments. The fact that although significant amount of Na is removed with H₃BO₃ acid and Na is increased with NaOH but the thermal stability remains the same indicates that Na cation is not an important parameter as much as K. HCl and H₃PO₄ acid treatments increased the surface area depending on the dissolution of amorphous material and H₃PO₄ was found to be more effective. However, the total pore size decreased due to formation of new micropores.     

Estimates of the physical parameters of remote planetary satellites

Since 1998, 97 new remote satellites of Jupiter, Saturn, Uranus, and Neptune have been discovered. Since their brightness is rather weak, it is difficult to perform their photometry and determine their physical parameters. For 27 satellites from this group, different authors carried out special photometric investigations. For the other 70 satellites, the magnitudes accompanying the results of astrometric observations published in Minor Planet Circulars (MPC) are the only photometric data. In the present study, the photometric model parameters for all of the 97 remote satellites have been determined. From the hypothetic values of albedo and material density of the satellites, their sizes and gravitation parameters have been estimated. The whole volume of the obtained results is available in the database of the natural planetary satellites (NSDB) (Arlot and Emelyanov, 2009) published on the Internet ().     

Sources and Databases for the Study of the Dynamics of Moons of Asteroids

A new database of all astrometric observations of moons of asteroids is offered. It has a simple structure and is accessible through the Internet. Regular database updating is provided when new observational results occur in publications. The database is located at the sites of the Natural Satellites Data Center created as a result of collaboration between the Sternberg Astronomical Institute of Moscow State University and the Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE). The database addresses in the Internet are https://doi.org/www.sai.msu.ru/neb/nss/indexr.htm and https://doi.org/nsdb.imcce.fr/obsposrespectively. On entering these sites, we need to select one of three languages, the Observation item, and the Astrometric positions of asteroids with moons item. The observational data are provided here with explanations and hyperlinks to the publications in the bibliographic database SAO/NASA Astrophysics Data System (ADS) Abstract Service.     

Geotechnical characterization of lignite-bearing horizons in the Afsin-Elbistan lignite basin, SE Turkey

The Afsin-Elbistan lignite deposit, with its 3.4 billion metric tons of reserves, is the biggest lignite basin and one of the most important resources for electrical energy production in Turkey. Kislakoy mining field was selected as the first opencast mine to feed four power station blocks of 300 MW each. Slope instability has been a continuing problem in the Kislakoy opencast mine. Particularly complex failures along a noncircular failure surface appearing at the final slope stage and covering large areas in the mine increase the importance of slope stability. This study outlines the geotechnical characteristics of the lignite-bearing horizons and describes the causes and mechanisms of slope instabilities, which threaten the safety of the mine. Quantitative X-ray diffraction (XRD) analyses were carried out using an interactive data processing system (SIROQUANT™) based on Rietveld interpretation methods. Parametric slope stability analysis and backanalysis were carried out for the failure that occurred at the northwestern final slope stage of the mine. The Spencer-Wright limiting state equilibrium method was used in order to determine with confidence the most representative values of regional shear strength parameters, to explain the failure mechanism, and to assess the conditions at the time of failure. In the analysis, phreatic and piezometric surfaces were considered.Site observations and numerous backanalyses of the slope failure reveal that a compound slide occurred where gyttja (contact zone) layers rest directly on the lignite. Gyttja (contact zone) contains the weakest material within the system. The analysis showed that the main cause of the northwestern slope instability was the presence of the groundwater flow within a Quaternary aquifer (through buried valleys), reducing the effective shear strength of the slope materials. It is also noted from backanalysis that the gyttja (contact zone) layer presents a shear strength at, or approaching, the residual value at the time of failure.     

Neural network model for liquefaction potential in soil deposits using Turkey and Taiwan earthquake data

Simplified methods have been practiced by researchers to assess nonlinear liquefaction potential of soil. Derived from several field and laboratory tests, various simplified procedures such as stress-based, strain-based, Chinese criteria, etc. have been developed by utilizing case studies and undisturbed soil specimens. In order to address the collective knowledge built up in conventional liquefaction engineering, an alternative general regression neural network model is proposed in this paper.To meet this objective, a total of 620 sets of data including 12 soil and seismic parameters are introduced into the model. The data includes the results of field tests from the two major earthquakes that took place in Turkey and Taiwan in 1999 and some of the desired input parameters are obtained from correlations existing in the literature.The proposed GRNN model was developed in four phases, mainly: identification phase, collection phase, implementation phase, and verification phase. An iterative procedure was followed to maximize the accuracy of the proposed model. The case records were divided randomly into testing, training, and validation datasets.Generating a model that takes into account of 12 soil and seismic parameters is not feasible by using simplified techniques; however, the proposed GRNN model effectively explored the complex relationship between the introduced soil and seismic input parameters and validated the liquefaction decision obtained by simplified methods. The proposed GRNN model predicted well the occurrence/nonoccurrence of soil liquefaction in these sites. The model provides a viable tool to geotechnical engineers in assessing seismic condition in sites susceptible to liquefaction.