Evaluation of Ground Vibration due to Surface Blasting at a Celestite Open-pit Mine     

Ali Kahriman 《Fragblast: International Journal for Blasting and Fragmentation》2001,5(1):21-34

In bench blast design, not only the technical and economical aspects, such as block size, uniformity and cost, but also the elimination of environmental problems resulting from ground vibration and air blast should be taken into consideration. Prediction of ground vibration components is of great importance when responding to and avoiding environmentally-related complaints. This paper presents the results of ground vibration measurements carried out in a celestite open-pit mine during blast optimisation studies. The particle velocity components (longitudinal, transversal, vertical and peak) and the airblast measurement results were evaluated considering the scaled distance relationship. The statistical analysis of 47 data sets yielded an empirical relationship between peak particle velocity and scaled distance. This approach which is suggested for the present site gives the 50% line and the upper bound 95% prediction limit with reasonable correlation.  相似文献   

Partial molar volume of water in phonolitic glasses and liquids     

Ali M. Bouhifd  Alan Whittington  Pascal Richet 《Contributions to Mineralogy and Petrology》2001,142(2):235-243

The volumes and expansivities of four hydrous phonolite glasses and liquids have been measured by dilatometry from 300 K up to the glass transition and over a 50 K interval just above the glass transition. The partial molar volume of water is independent of the water content for the glass and liquid phases, with values of about 11.0ǂ.5 and 17.1ǂ.9 cm³/mol at 300 and 800 K, respectively. The partial molar thermal expansivity of water in phonolite glasses is about 8᎒^-5 K^-1, a result similar to recently published values for different silicate compositions, and about 36.5᎒^-5 K^-1 in phonolite liquids. The implications for melt density and water dissolution are discussed.  相似文献   

巴基斯坦沿海地区地震危险性分析   总被引：1，自引：0，他引：1       下载免费PDF全文

ShahidA．Khan M．AliShah M．Qaisar 《地震学报》2003,25(4):361-373

通过确定性和概率性方法，对发展迅速的巴基斯坦沿海地区进行了地震危险性评估．根据该地区的地震构造和地质条件，确定了5个地震区域的11个断层作为该地区的潜在震源，计算了每个潜在震源的最大可能震级．根据与之相关震源的最大可信震级，计算了7个沿海城市的峰值加速度（PGA）．瓜达尔（Gwadar）和奥尔马腊（Ormara）的峰值加速度分别为0.21和0.25 g，处于地震危险性水平较高的地区；杜尔伯德（Turbat）和卡拉奇（Karachi）位于地震危险性水平较低的地区，峰值加速度小于0.1 g．同时，分别绘制了50年和100年超越概率为10％的PGA区划图，区划图的分区间隔为0.05 g．   相似文献   

Detrital zircon U–Pb ages along the Yarlung-Tsangpo suture zone, Tibet: Implications for oblique convergence and collision between India and Asia     

Jonathan C. Aitchison  Xiaoping Xia  Alan T. Baxter  Jason R. Ali 《Gondwana Research》2011,20(4):691-709

Age-dating of detrital zircons from 22 samples collected along, and adjacent to, the Yarlung-Tsangpo suture zone, southern Tibet provides distinctive age-spectra that characterize important tectonostratigraphic units. Comparisons with data from Nepal, northern India and the Lhasa and Qiangtang terranes of central Tibet constrain possible sources of sediment, and the history of tectonic interactions.Sedimentary rocks in the Cretaceous–Paleogene Xigaze terrane exhibit strong Mesozoic detrital zircon peaks (120 and 170 Ma) together with considerable older inheritance in conglomeratic units. This forearc basin succession developed in association with a continental volcanic arc hinterland in response to Neotethyan subduction under the southern edge of the Eurasia. Conspicuous sediment/source hinterland mismatches suggest that plate convergence along this continental margin was oblique during the Late Cretaceous. The forearc region may have been translated > 500 km dextrally from an original location nearer to Myanmar.Tethyan Himalayan sediments on the other side of the Yarlung-Tsangpo suture zone reveal similar older inheritance and although Cretaceous sediments formed 1000s of km and across at least one plate boundary from those in the Xigaze terrane they too contain an appreciable mid-Early Cretaceous (123 Ma) component. In this case it is attributed to volcanism associated with Gondwana breakup.Sedimentary overlap assemblages reveal interactions between colliding terranes. Paleocene Liuqu conglomerates contain a cryptic record of Late Jurassic and Cretaceous rock units that appear to have foundered during a Paleocene collision event prior the main India–Asia collision. Detrital zircons as young as 37 Ma from the upper Oligocene post-collisional Gangrinboche conglomerates indicate that subduction-related convergent margin magmatism continued through until at least Middle and probably Late Eocene along the southern margin of Eurasia (Lhasa terrane).Although the ages of detrital zircons in some units appear compatible with more than one potential source with care other geological relationships can be used to further constrain some linkages and eliminate others. The results document various ocean closure and collision events and when combined with other geological information this new dataset permits a more refined understanding of the time–space evolution of the Cenozoic India–Asia collision system.  相似文献   

A Metamorphic Core Complex Model for the Host of Uranium Mineralization in the Khoshoumi Mountain,Central Iran     

Ali YASSAGHI  Mehdi MASOODI 《Resource Geology》2011,61(3):259-269

A metamorphic core complex model is proposed for Khoshoumi Mountain uranium mineralization located in the Bafq–Saghand metallogenic zone of central Iran. Uranium mineralization occurred in the Chapedoni metamorphic complex. Detailed structural analysis of the complex leads to the interpretation that the mineralization is spatially concentrated in a low angle shear zone of mylonitized migmatite, the lower ductile part of the Chapedoni metamorphic complex. The shear zone that has top to the NE sense of shear in the northeastern and southeastern parts of the mountain and top to the WNW sense of shear in the southwestern part is a detachment zone to the Chapedoni Metamorphic Core Complex (CMCC). The Eocene granite is the plutonic core to the CMCC. The shear zone is cut by several NE‐trending left‐lateral strike‐slip faults. This later faulting is interpreted to account for the significant enrichment of uranium in the southern part of the mountain. The bimodal distribution of radiometric data gathered from exploratory drill holes in this part of the mountain constrains this interpretation. That is, the lower value is from the shear zone across the area but the higher value is from the places that the shear zone is cut by the transverse faults.  相似文献   

Helium measurements of pore fluids obtained from the San Andreas Fault Observatory at Depth (SAFOD, USA) drill cores     

S. Ali  M. Stute  T. Torgersen  G. Winckler  B. M. Kennedy 《Hydrogeology Journal》2011,19(1):237-247

⁴He accumulated in fluids is a well established geochemical tracer used to study crustal fluid dynamics. Direct fluid samples are not always collectable; therefore, a method to extract rare gases from matrix fluids of whole rocks by diffusion has been adapted. Helium was measured on matrix fluids extracted from sandstones and mudstones recovered during the San Andreas Fault Observatory at Depth (SAFOD) drilling in California, USA. Samples were typically collected as subcores or from drillcore fragments. Helium concentration and isotope ratios were measured 4?C6 times on each sample, and indicate a bulk ⁴He diffusion coefficient of 3.5?±?1.3?×?10^?C8 cm²?s^?C1 at 21°C, compared to previously published diffusion coefficients of 1.2?×?10^?C18 cm²?s^?C1 (21°C) to 3.0?×?10^?C15 cm²?s^?C1 (150°C) in the sands and clays. Correcting the diffusion coefficient of ⁴He_water for matrix porosity (??3%) and tortuosity (??6?C13) produces effective diffusion coefficients of 1?×?10^?C8 cm^2?s^?C1 (21°C) and 1?×?10^?C7 (120°C), effectively isolating pore fluid ⁴He from the ⁴He contained in the rock matrix. Model calculations indicate that <6% of helium initially dissolved in pore fluids was lost during the sampling process. Complete and quantitative extraction of the pore fluids provide minimum in situ porosity values for sandstones 2.8?±?0.4% (SD, n?=?4) and mudstones 3.1?±?0.8% (SD, n?=?4).  相似文献   

Numerical investigation of undrained cavity expansion in fine-grained soils     

Abid Ali  Thomas Meier  Ivo Herle 《Acta Geotechnica》2011,6(1):31-40

Based on the spherical cavity expansion (SCE) problem, Cudmani and Osinov (Can Geotech J 38:622–638, 2001), Osinov and Cudmani (Int J Numer Anal Method Geomech 25:473–495, 2001) developed a semi-empirical method of interpretation of CPT for coarse-grained soils (sand, gravel) using a hypoplastic constitutive model. Using a material-independent shape factor, the cone penetration resistance was related to the limit pressure required to expand a spherical cavity. The shape factor was observed to be a function of the soil state only, in particular the pressure-dependent relative density. This paper presents an analogous interpretation technique for CPT in fine-grained soils using the shape factor concept, Cavity Expansion approach, and a hypoplastic constitutive model. Relations for the shape factor and the limit pressure have been proposed based on the parameters affecting these quantities. A validation of the proposed interpretation technique with experimental results has also been performed.  相似文献   

Integrated coastal management plan in free trade zones, a case study   总被引：1，自引：0，他引：1  

Ali Pak  Farhad Majd 《Ocean & Coastal Management》2011,54(2):129-136

Free Trade Zones (FTZs) around the world offer special advantages to investors and facilitate import/export of goods in order to boost the regional economy. Integrated coastal management in these areas faces special challenges in addition to what ordinary ICZMs usually encounter. For a successful ICZM plan, the very strong business orientation in FTZs has to be taken into account, while other important aspects such as environmental, social, and cultural issues should not be overlooked. The problem becomes more difficult where the free zone is situated in sensitive and valuable environmental circumstances.Kish Island, a free trade zone in the Persian Gulf region, has recently been the focus of a major ICZM study. In order to address the different needs of various stakeholders in the island, four strategic management plans are prepared. The investigations carried out in the course of this study indicated that the required management plans for this free trade zone should be provided with a spatial-plan-oriented approach, otherwise the integration can hardly be achieved and implemented.This article describes Kish FTZ characteristics and problems that required ICZM initiatives, the methodology for ICZM study, the preparation and implementation of strategic management plans considering the free zone obligations, and the need for a spatial umbrella plan to facilitate the integration among different plans in the implementation process.  相似文献   

Costs related to drowning and near drowning in northern Iran (Guilan province)     

Ali Davoudi-Kiakalayeh  Koustuv DalalShahrokh Yousefzade-Chabok  Bjarne JanssonReza Mohammadi 《Ocean & Coastal Management》2011,54(3):250-255

In Iran and many other low- and middle-income countries, few studies have been carried out in order to assess which cost analysis methods should be undertaken at the household and community level in relation to incidences of drowning. In this study, we have attempted to develop a model for estimating the impact of the economic burden that drowning and near drowning events incur for victims’ families in the Guilan province in the north of Iran by using an incidence approach. During the financial year of March 2007 to 2008, the following cost-related aspects of drowning episodes were evaluated: (note: main cost elements were income adjusted by family and years) medical costs, productivity loss costs and death costs. A total of 137 drowning fatalities and 104 near drowning incidents were recorded. Males in the age span of 10-29 years constitute a majority of the epidemiology and economy data. When the number of variables included in cost analysis was expanded, the estimated burden of economic duress increased dramatically; however, drowning cost for one drowned victim was equivalent to 17 times the country’s gross domestic product(GDP) per capital. Identification of injured person-based costs in this study will enable development of more effective prevention programs and provide indicators of other costs related to drowning episodes such as property damage and the impact of these accidents on community services and the public health care system.  相似文献   

Bed composition generation for morphodynamic modeling: case study of San Pablo Bay in California, USA   总被引：2，自引：1，他引：1  

Mick van der Wegen  Ali Dastgheib  Bruce E. Jaffe  Dano Roelvink 《Ocean Dynamics》2011,61(2-3):173-186

Applications of process-based morphodynamic models are often constrained by limited availability of data on bed composition, which may have a considerable impact on the modeled morphodynamic development. One may even distinguish a period of “morphodynamic spin-up??in which the model generates the bed level according to some ill-defined initial bed composition rather than describing the realistic behavior of the system. The present paper proposes a methodology to generate bed composition of multiple sand and/or mud fractions that can act as the initial condition for the process-based numerical model Delft3D. The bed composition generation (BCG) run does not include bed level changes, but does permit the redistribution of multiple sediment fractions over the modeled domain. The model applies the concept of an active layer that may differ in sediment composition above an underlayer with fixed composition. In the case of a BCG run, the bed level is kept constant, whereas the bed composition can change. The approach is applied to San Pablo Bay in California, USA. Model results show that the BCG run reallocates sand and mud fractions over the model domain. Initially, a major sediment reallocation takes place, but development rates decrease in the longer term. Runs that take the outcome of a BCG run as a starting point lead to more gradual morphodynamic development. Sensitivity analysis shows the impact of variations in the morphological factor, the active layer thickness, and wind waves. An important but difficult to characterize criterion for a successful application of a BCG run is that it should not lead to a bed composition that fixes the bed so that it dominates the “natural??morphodynamic development of the system. Future research will focus on a decadal morphodynamic hindcast and comparison with measured bathymetries in San Pablo Bay so that the proposed methodology can be tested and optimized.  相似文献