Seismic event of January 22, 2010 near Bełchatów,Poland

The paper summarizes the findings about a seismic event on January 22, 2010, near Bełchatów, Poland, in terms of data, event location, magnitude and source parameters.     

A study of the interaction among mining-induced seismic events in the Legnica-Głogów Copper District,Poland

We applied the Coulomb stress transfer technique to investigate interactions among seismic events induced by mining works in the Rudna mine in the Legnica-Glogów Copper District in Poland. We considered events with energy greater than 10⁵ J from the period 1993–1999. We examined the influence of the cumulative static stress changes (ΔCFF) due to previous events on the generation of subsequent ones. The results indicate that in many cases strong mining tremors produce changes in the state of stress of a sufficient magnitude to influence subsequent events. The location of over 60% of events is consistent with stress-enhanced areas where the values of ΔCFF were above 0.01 MPa. For most of the events located inside areas of a calculated negative ΔCFF, their modelled rupture zone was partially located inside stress enhanced area, providing thus additional evidence for possible triggering at the nucleation point.     

Free core nutation period inferred from the gravity measurements at Józefosław

The Free Core Nutation (FCN) is an important eigenmode which affects both Earth rotation and body tide. The FCN parameters, the resonance period and the quality factor are important for understanding the dynamics of the Earth at nearly diurnal periods. Those parameters are usually estimated either from the Very Long Baseline Interferometry (VLBI) observations of nutation, or from the tidal gravity measurements. In this paper we investigate the determination of the FCN parameters from gravity records covering a period of more than three years, collected with the use of a LaCoste&Romberg Earth Tide no. 26 gravimeter, located at Józefos?aw observatory near Warsaw. From the resonant enhancements of gravimetric factors and phases of diurnal tidal gravity waves, we could infer the FCN period to be equal to 430 sidereal days. This result is in very good agreement with previous gravimetric and VLBI nutation results, confirming the discrepancy in the dynamic flattening of the outer liquid core from its theoretical value based on the hydrostatic equilibrium assumption. The estimated FCN quality factor (Q ≈ 1300) is considerably smaller than the VLBI nutation result, which confirms that the local gravity measurements are more sensitive than VLBI global analyses to site-dependent phenomena (such as atmospheric and indirect ocean tidal effects). We also investigated the importance of gravimetric corrections in the FCN analysis, including numerical tests and simulations. This allowed us to estimate the uncertainty of FCN parameters due to improper or incomplete set of environmental corrections. We took also into account the impact of gravimetric factor errors and tidal wave selection on estimated FCN parameters. We demonstrated that despite relatively noisy measurements due to unfavorable gravimeter location, we were able to obtain very good results in case when proper correction and tidal wave selection were applied.     

Groundwater Renewal in the Middle Odra River Catchment Based on Flow Model and Isotopic Data – the Lubin Głogów Copper Region,Poland

In the area of intense mining within the Lubin Głogów Copper Region the investigation of groundwater renewal was made according to two methods: a numerical flow model and isotopic analysis. The results of model simulations show that within the shallow aquifer the groundwater renewal is quick and mostly depends on infiltration within the recharge zones. An average time of groundwater flow between recharge and discharge areas in the representative part of the entire system has been obtained as 130 years. The content of isotopes was determined in samples collected as well from the mine excavations as from water intakes. The measurements were done on 17 samples. Results of isotopic studies indicate that the relationship of δD – δ18O in groundwater gathers along the established local meteoric water line (MWL) δD = 7.58 δ18O + 4.45. Deep groundwaters that create an inflow to the mines were formed by infiltration in Holocene with reference to two of total four mines and probably in Eopleistocene in another two.     

Application of electrical resistivity imaging (ERI) for the assessment of peat properties: a case study of the Całowanie Fen,Central Poland

Complex studies were carried out to recognize the fen structure and peat properties in the Ca?owanie Fen area, belonging to the Natura 2000 network. The studies were conducted in two study areas that differ significantly in terms of peat thickness. Electrical resistivity imaging (ERI) was used to identify the properties of the peat and its substrate, such as thickness and electrical resistivity. Comparison of the field studies with the laboratory tests has shown that the ash content rises electrical resistivity in peat. In addition, the study has shown that the application of non-invasive geophysical methods in protected areas is justified. The fen, as a medium containing mostly water, was a proper test area for the ERI measurements.     

Determination of Ventilation Channels In Urban Area: A Case Study of Wrocław (Poland)

Urban areas are among the roughest landscapes in the Earth and its aerodynamical properties are responsible for a lot of processes and phenomena of urban climate, such as surface drag and pollutant dispersion. These properties can be quantitatively expressed by various parameters, with zero plane displacement height (z _d) and roughness length (z ₀) as the most frequently applied. Based on remotely gathered (LIDAR scan) height data and morphometric methods of roughness calculations, the comprehensive procedure to determine ventilation channels in urban area is proposed and implemented on the example from Wroc?aw, Poland. Morphometric analysis of urban structure allowed establishing a proper database of aerodynamic parameters of the city. Then a series of maps of the city showing the distribution of two roughness parameters were prepared. GIS tools were used to carry out the analysis of roughness data, assuming various directions of wind flow. It enabled to determine the locations of potential ventilation paths in the city which, if combined, form large ventilation channels. They may have a significant role in improving air quality and be a valuable source of information for local government responsible for the appropriate development of the city.     

Quantitative and Qualitative Assessment of Soil Erosion Risk in Małopolska (Poland), Supported by an Object-Based Analysis of High-Resolution Satellite Images

In 2011 the Marshal Office of Ma?opolska Voivodeship decided to evaluate the vulnerability of soils to water erosion for the entire region. The quantitative and qualitative assessment of the erosion risk for the soils of the Ma?opolska region was done based on the USLE approach. The special work-flow of geoinformation technologies was used to fulfil this goal. A high-resolution soil map, together with rainfall data, a detailed digital elevation model and statistical information about areas sown with particular crops created the input information for erosion modelling in GIS environment. The satellite remote sensing technology and the object-based image analysis (OBIA) approach gave valuable support to this study. RapidEye satellite images were used to obtain the essential up-to-date data about land use and vegetation cover for the entire region (15,000 km²). The application of OBIA also led to defining the direction of field cultivation and the mapping of contour tillage areas. As a result, the spatially differentiated values of erosion control practice factor were used. Both, the potential and the actual soil erosion risk were assessed quantificatively and qualitatively. The results of the erosion assessment in the Ma?opolska Voivodeship reveal the fact that a majority of its agricultural lands is characterized by moderate or low erosion risk levels. However, high-resolution erosion risk maps show its substantial spatial diversity. According to our study, average or higher actual erosion intensity levels occur for 10.6 % of agricultural land, i.e. 3.6 % of the entire voivodeship area. In 20 % of the municipalities there is a very urgent demand for erosion control. In the next 23 % an urgent erosion control is needed. Our study showed that even a slight improvement of P-factor estimation may have an influence on modeling results. In our case, despite a marginal change of erosion assessment figures on a regional scale, the influence on the final prioritization of areas (municipalities) according to erosion control needs is visible. The study shows that, high-resolution satellite imagery and OBIA may be efficiently used for P-factor mapping and thus contribute to a refined soil erosion risk assessment.     

认清形势,明确任务,抓住机制,依法行政,努力提高江苏防震减灾工作水平

总结回顾了江苏二十多年来的防震减灾工作,分析了当前搞好防震减灾工作的形势,从７个方面阐述了要抓住机遇,依法行政提高全省防震减灾工作水平的有关问题。     

Site specific prediction equations for peak acceleration of ground motion due to earthquakes induced by underground mining in Legnica-Głogów Copper District in Poland

Ground motion database from the region of ?elazny Most tailings pond, the largest in Europe ore-flotation waste repository, is used to identify ground motion prediction equations (GMPE-s) for peak horizontal and peak vertical acceleration. A GMPE model including both geometrical spreading and anelastic damping terms cannot be correctly identified and the model with only spreading term is accepted. The analysis of variance of this model’s residuals with station location as grouping variable indicates that station locations contribute significantly to the observed ground motion variability. Therefore, a site specific GMPE model with relative site amplifications is assessed. Despite short distances among stations, the amplification considerably vary from point to point, up to 1.8 times for the horizontal and 3.5 times for the vertical peak amplitude. The model including site effects enhances GMPE-s fit to observations, explains more than 60% dependent variables variability and correctly accounts for site effects.     

The fault plane of the 1991,Datong-Yang-gao,Shanxi,China,Ms=5.8 earthquake

Ｔｈｅｆａｕｌｔｐｌａｎｅｏｆｔｈｅ１９９１，Ｄａｔｏｎｇ－Ｙａｎｇ－ｇａｏ，Ｓｈａｎｘｉ，Ｃｈｉｎａ，Ｍｓ＝５．８ｅａｒｔｈｑｕａｋｅＭｉｎｇＷＡＮＧ（王鸣），Ｌｉａｎ－ＱｉａｎｇＺＨＡＮＧ（张廉强）ａｎｄＰｅｉ－ＤｅＷＡＮＧ（王培德）（Ｉｎｓｔｉ...     

梅岭,梅关,古道与梅花

梅岭,又名大庾岭,为南岭山系五岭之首。梅关是粤赣交界的险关要塞,素有“岭南第一关”之誉,秦汉以前已存在。梅岭以梅花著称。古道与关同时出现,到唐初张九龄扩展岭路成坦途。