Women’s use of public space and sense of place in the Raval (Barcelona)

This article deals with women's use of public space and sense of place in El Raval, a neighbourhood located in the historical center of Barcelona. Attention will be paid to discover to what degree the existence of a quality public space fosters the creation of socially meaningful places, thus contributing to the construction of womens sense of place and urban identities. A qualitative approach, based on direct observation and in-depth interviews with women living in the neighbourhood, has allowed us to capture the main aspects of the building of a sense of place and belonging, that is the use of public space and facilities, the attitude towards living in the neighbourhood, etc. This revised version was published online in July 2006 with corrections to the Cover Date.     

Hazard degree identification and coupling analysis of the influencing factors on goafs

In China, there are a large number of mined-out area which bring a great hidden danger to the mine enterprise’s safety production and people’s life and property. Therefore, the stability evaluation and the mechanism analysis of goafs have become a hot issue in the study on sustainable development of mining industry. To solve the complexity, concealment, and uncertainty of goaf influencing factors, 14 factors, i.e., rock mass structure, goaf span, exposed area, and so on, were selected as the evaluation indexes according to an iron ore. Then, the hazard evaluation model of goaf was established by using the information entropy and the unascertained measurement (UM) theory to identify the hazard degree, and the hazard importance degree index was put forward by changing the influencing factors and its index value to quantitatively analyze the coupling degree of influencing factors. This paper takes the BFZ-8 goaf as an example to evaluate and analyze the goaf stability. The results show that the evaluation model about UM and the experimental schemes are feasible and practicability, and the UM evaluation grades are consistent with the fuzzy evaluation grades and the actual risk grades in the case of multi-factor coupling. And the experimental results quantitatively reflect the coupling degree of the influencing factors by comparing the relative change rate of the importance degree, and the coupling results are consistent with the actual situation. So, the method can guide the production safety of mine, protect life and property safety of miners, and provide technical support and a new method for hazard degree identification of the goaf.     

Risk assessment of metals from groundwater in northeast Rajasthan

In Shear strength reduction (SSR) technique, the factor of safety (FOS) is defined as the ratio of the material’s actual shear strength to the minimum shear strength required to prevent failure. Failure surface is found automatically through the zones within the material, where applied shear stresses cross the shear strength of the material. In this paper, a review of the technique is discussed in reference to FLAC. A brief background of the approach together with detailed procedure is presented.An attempt is made to exhibit the shear strength dependency of the strain. As stability of the slope is a function of the shear strength, the development of failure strain reflects the potential failure zone of slope. The shear strain developed in the slope increases with reduction in the shear strength and is reflected in the analysis. The concept of failure ratio (R_f) is incorporated in shear strength reduction technique and is demonstrated. Relationships between the critical shear strength reduction ratio and the safety factor are examined.     

A new approach to modeling perpendicular fabrics in porphyritic plutonic rocks using the finite element method

A growing body of field evidence indicates that hypersolidus fabrics preserved in syntectonic plutons are likely to have formed in highly crystallized ‘rigid sponge’ magma. This paper demonstrates that such magma could be idealized as a rheological solid and that the development of non-coaxial fabrics in plutonic rocks can very conveniently be modeled in the framework of solid mechanics. Using the finite element method (FEM), we modeled two strain regimes of small magnitudes (plane-strain horizontal simple shear with the shear strain γ of up to 0.30 and plane-strain pure shear of up to 15% shortening) superposed onto vertically oriented and variously spaced elastic phenocrysts set in the viscoelastic matrix. In the simple shear regime, the phenocrysts slightly rotate toward the shear plane, while the principal strain directions in the matrix are instantaneously oriented at an angle of about 45° or less to the phenocryst fabric. Simple shear thus can only lead to the formation of oblique phenocryst and matrix fabrics. By contrast, the vertical phenocryst fabric is maintained in the pure shear regime, and a new horizontal fabric can develop almost instantaneously in the matrix even for small amounts of superposed shortening (5% shortening after 10 ky in our model). We conclude that such a mechanism can easily produce perpendicular hypersolidus fabrics in plutonic rocks and that only a very short time span (first thousands of years) is required to develop magmatic fabric in a pluton for ‘normal’ rates (10⁻¹⁵ to 10⁻¹³ s⁻¹) of tectonic deformation.     

Effects of size and strain rate on the mechanical behaviors of rock specimens under uniaxial compression

Size and strain rate are two key factors that dramatically influence the estimation of rock mechanical behaviors. To better understand the effects of size and strain rate on measured rocks, rock specimens with six different sizes were tested at six different strain rates under uniaxial compression using the MTS 815 Rock Mechanics Test System. Having determined that the size and strain rate significantly affect the peak strain, peak stress, elastic modulus, acoustic emission (AE), and failure pattern of the rock specimens, the relation was established between the strength and the size and strain rate of red sandstone. And the variation was revealed among the size and strain rate, the AE, and the failure pattern. It turned out that the peak stress was negatively correlated with the rock size and was positively correlated with the strain rate. When the length to diameter ratio (L/D) of the rock specimen was less than 2.0, the AE appeared mildly. The AE quantities gradually increased before the peak stress, and then sharply decreased after the peak stress. The failure pattern of the rock specimen was relatively complicated, with a fracture plane appearing along the axial direction. Conical failure type was also presented. When the L/D ratio of the specimen was greater than 2.0, the AE characteristics of red sandstone showed the radical model. There were relatively few AE rings before the peak stress. But the AE rings increased suddenly and dramatically during the peak stress. The rock specimens primarily failed with a single shear plane. Moreover, with an increase in the strain rate, the AE activities were enhanced and the AE quantities increased. When the strain rate of the rock specimen was less than 5.0?×?10^?4/s, the rock specimen failed with a shear or tensile-shear pattern. And when the strain rate was greater than 5.0?×?10^?4/s, the rock specimen tended to fail in a conical pattern.     

Quantitative basin characterisation to refine debris-flow triggering criteria and processes: an example from the Italian Western Alps

This paper investigates rapid channelized debris flow related to rainfalls in small alpine basins. Its goal is to evaluate and correlate different geological and technical aspects with predisposing and triggering factors that can control these phenomena. The study area is the upper part of the Susa Valley where 12 small basins were selected. For each of them, lithological, geomorphological, climatic and technical information were mapped and analysed. Debris-flow triggering conditions, flow and depositional processes were related to physical characteristics of the basin that can be easily measured and quantified. At least three different groups of basins were found: G1) basins with one event each 4–6 years, characterised by massive or blocky calcareous rocks, G2) basins with more than one event per year that show an abundance of layered or sheared fine-grained rocks and G3) basins with recurrence levels exceeding 10 years, activated only by heavy and prolonged rainfalls, marked by massive or blocky coarse-grained igneous rocks. Furthermore, important morphometric differences were found. These considerations are useful in terms of hazard zonation and risk mitigation.     

Scale of pluton/wall rock interaction near May Lake,Yosemite National Park,CA, USA

Interaction of magma with wall rock is an important process in igneous petrology, but the mechanisms by which interactions occur are poorly known. The western outer granodiorite of the Cretaceous Tuolumne Intrusive Suite of Yosemite National Park, California, intruded a variety of metasedimentary and igneous wall rocks at 93.1 Ma. The May Lake metamorphic screen is a metasedimentary remnant whose contact zone exhibits a variety of interaction phenomena including xenolith incorporation, disaggregation, and partial melting. The chemical contrast of these metasedimentary rocks with the invading pluton provides an excellent measure of pluton/wall rock interactions. Wall rock xenoliths (mostly pelitic quartzite) are predominantly located in an elongate horizon surrounded by a hybridized fine-grained granodiorite. Initial Sr and Nd isotopic ratios of the hybridized granodiorite indicate significant local incorporation of crustal material. Major- and trace-element geochemical data indicate that contamination of the granodiorite occurred via selective assimilation of both high-K and low-K, high-silica partial melts derived from pelitic quartzite. Although the hybridized granodiorite shows significant amounts of contamination, adjacent to xenoliths the proportion of contamination is undetectable more than a meter away. These results indicate that the chemical and isotopic variability of the Tuolumne Intrusive Suite is not caused by magma contamination via in situ wall rock assimilation.     

Determining magma flow in sills,dykes and laccoliths and their implications for sill emplacement mechanisms

Three-dimensional seismic data from the Faeroe-Shetland Basin provides detailed information on the relationships between sills, dykes, laccoliths and contemporaneous volcanic activity. The data shows that sills are predominantly concave upwards, being complete or partial versions of radially or bilaterally symmetrical forms that possess flat inner saucers connected to a flat outer rim by a steeply inclined sheet. Such morphologies are only partially modified by pre-existing faults. Sills can be sourced from dykes or the steep climbing portions of deeper sills. Both sills and dykes can provide magma to overlying volcanic fissures and sills can be shown to feed shallow laccoliths. Magma flow patterns, as revealed by opacity rendering, suggest that sills propagate upwards and outwards away from the magma feeder. As an individual sill can consist of several leaves emplaced at different stratigraphic levels, and as a sill or dyke can provide magma to volcanic fissures, other sills and laccoliths, the data suggests that neutral buoyancy concepts may not provide a complete explanation for the mechanism and level of sill emplacement. Instead, the data suggests that the presence of lithological contrasts, particularly ductile horizons such as overpressured shales may permit sill formation at any level below the neutrally buoyant level. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. Ken Thomson–deceased, April 2007     

Ecological Effects of Shoreline Armoring on Intertidal Habitats of a Puget Sound Urban Estuary

Shoreline armoring is extensive in urban areas worldwide, but the ecological consequences are poorly documented. We mapped shoreline armoring along the Duwamish River estuary (Washington State, USA) and evaluated differences in temperature, invertebrates, and juvenile salmon (Oncorhynchus spp.) diet between armored and unarmored intertidal habitats. Mean substrate temperatures were significantly warmer at armored sites, but water temperature similar to unarmored habitats. Epibenthic invertebrate densities were over tenfold greater on unarmored shorelines and taxa richness double that of armored locations. Taxa richness of neuston invertebrates was also higher at unarmored sites, but abundance similar. We did not detect differences in Chinook (O. tshawytscha) diet, but observed a higher proportion of benthic prey for chum (O. keta) from unarmored sites. Given that over 66% of the Duwamish shoreline is armored—similar to much of south and central Puget Sound—our results underscore the need for further ecological study to address the impacts of estuary armoring.