Iranian Journal of Earth Sciences
Volume:2 Issue: 1, Apr 2010

Hard rock aquifers for the purpose of this Paper mean the non-carbonate, fractured rock aquifers in the terrain covered by crystalline basement complex, metamorphic rocks and also by extensive effusive volcanic rocks like the basalts of western India (Deccan traps. Ground water development in hard rock aquifer areas has always played a secondary role compared to that in the areas having high-yielding unconsolidated or semi-consolidated sediments and carbonate rocks. This has been due to the relatively poor ground water resources in hard rocks, low specific capacity of wells, erratic variations and discontinuities in the aquifer properties, and difficulties in exploration and assessment of the resource. It should, however, be remembered that for the millions of farmers in developing countries, having their small farms in the barren landscape of fractured hard rock terrain, whatever small supply available from these poor aquifers is the only hope for upgrading their standard of living by growing irrigated crops or by protecting their rain-fed crops from the vagaries of rainfall. It is also their only source for drinking water for the family and cattle. In many developing countries, hard rock hydrogeologists have therefore, an important role to play. In the developed countries, the interest in hard rock hydrogeology, apart from drinking water supplies to small communities, is recently promoted by the prospects of using these low permeability rocks for the storage of hazardous nuclear and chemical wastes. The study of ground water flow through faults, fissures and fractures is also of interest to scientists studying the migration of contaminants. Hard rock hydrogeologists, the world over, are therefore divided into two main groups: Those interested in obtaining ground water for domestic, irrigational or industrial use by exploring fractured and permeable zones in a relatively less permeable matrix of hard rock and those interested in locating impermeable or the least permeable zones for storage of hazardous nuclear waste. Ironically, for the first group even the most permeable zones are often not good enough to yield adequate water supply, while for the second group even the least permeable zones are often not good enough for safe storage of hazardous nuclear waste over a prolonged period of a few hundred years. This Paper discusses the occurrence of ground water and the precautions for sustainable development of ground water in arid and semi-arid regions, in view of the forthcoming climatic changes. It emphasizes the need for recharge augmentation hand-in-hand with development of new wells, so that the new development does not harm the traditional practices. In India, the neglect of recharge augmentation has caused lowering of water table and drying-up of old dug-wells of 12m to 15 m depth, which used to provide irrigational and drinking water supply for last several centuries. In Iran, many Qanats have dried up because of lowering of water table due to heavy pumping of ground water from newly developed deep tube-wells in their vicinity. The goal in many countries has, therefore, shifted from ground water development to ground water management which includes management of the quantity on Supply side and Demand side and also the management of ground water quality, especially with respect to pollution and salt water intrusion. Pollution of ground water in urban environment is becoming a cause of worry because in many developing countries there is a heavy migration of population from rural areas to urban centers and providing safe quality of drinking water to this population and managing the waste water generated in the cities and towns, is a major problem. The role of UNESCO-IUGS-IGCP Project GROWNET (Ground Water Network for Best Practices in Ground Water Development in Low Income Countries) is also described towards the end of this Paper. The Author is the Project Leader for GROWNET.

In order to meet the significantly increased metal demand of the world market, it has been decided to expand the capacity of the existing alumina refineries and to set up new plants (more than 2 Mt/a each). The selection among the bauxite sources is based on previous exploration data, such as: tonnage, grade, mineralogy, etc., the geographical position of the deposit, existing natural and constructed infrastructure and the distance from deep water ports. Environmental and political risks are also investigated. Decision making is a complex task in which the close co-operation of professionals of the bauxite-alumina industry is needed. The authors specify the most determinant factors which are investigated for decision making and call attention to the fact that, in many cases, inconsistent data are compared as if they were equal in value or identical such as: the reliability of explorations made for deposits in various countries, and at different times is also different, the methods applied in reserve calculation and resource estimate are different, the qualitative criteria used for commercial grade ores are different, no numeric data are available showing the possible error in reserve calculation the terminology used for bauxite categories is also different.Adequate attention is never given for the further development of possible prospects; their investigation may be neglected in the selection. As a consequence, when different resources are compared, the geological risks (stability in bauxite production) cannot adequately be taken into account. For minimizing the transport costs (either the bauxite supply to the alumina plant or the alumina shipping to the smelter or both) the geographical position of the raw material is one of the most significant economic factors in the value of the deposit. There are several regions in the world which are so rich in bauxite potential (West Africa, edge of the Guyana Shield in Venezuela and Brazil, the Amazon Basin in Brazil, Weipa Gove in Australia, Eastern Ghats in India, etc.) where new deposits should be explored as a function of their geographical position. The landsat interpretation has proved to be an excellent tool for establishing priorities among the options. The authors give a short review and comparison of the most significant regions and deposits focusing their interests on the: tonnage, grade and mineralogy, further prospects (undiscovered) deposits, infrastructure, distance from mine/deposits to the deep water ports, available alumina content (for a low or a high temperature procedure) for estimating the bauxite consumption per ton of alumina, soluble silica content for estimating the caustic soda consumption per ton of alumina, beneficiation cost in some cases, risk factors (geological, environmental, political and national) The authors conclude, that in spite of the fact that about 30 - 35 billion tons of bauxite have been registered so far as proved + probable reserves and a further 55 – 60 billion tons can be estimated as possible resources in the world, finding new resources in better geographical locations and their exploration may be advantageous. The new exploration data must be more reliable, as well. The costs of reconnaissance and exploration may be far below the haulage costs.

The research used the satellite image (Landsat 7 ETM) within the thermal infrared sixth band (TIR6) and geographic information system (GIS) to determine the air pollution and its relationship with the land cover (LC) and land use (LU) of Baghdad city. Concentration of total suspended particles (TSP), lead (Pb), carbon oxides (CO, CO2), and sulphur dioxide (SO2) were obtained from 22 ground measuring stations, where the stations are classified into industrial, commercial and residential and are distributed within the city of Baghdad. The digital number (DN) corresponding to the sites of groundtruth stations for measuring air pollutants was converted to the values of the spectral radiation (Lr), brightness temperature sensor (T) and land surface temperature (LST) of the satellite image (Landsat 7 ETM +) within TIR6. The results indicated a significant correlation between air pollutants and satellite image data have also shown results of the spatial analyst air pollutants and the satellite image data by using GIS and supervised classification results. They show a relationship between the concentration of air pollutants and land surface temperature with the land cover and land use classification (LC, LU) for Baghdad city. The results of the research gives evidence of a link between air pollutants derived from the measurement stations of ground and satellite data within the range of Thermal IR.

In 2007, research was carried out to determine the type and amount of asbestos fibers in a Croatian factory with a long history of making asbestos-containing products.Since the 1970s, asbestos fibres have been considered carcinogenic in humans i.e as a known cancer-causing agent. In the environment, asbestos fibres are inactive and naturally resist biodegradation. In time, fibres can only be ground into smaller particles by mechanical force. These small particles in the air present a health hazard. Because of their small size, shape and durability, asbestos fibres can easily be inhaled and stick to the lung tissue, causing serious respiratory problems. Among these are diseases with long latency periods of 10 to 40 years such as: asbestosis, mesothelioma and lung cancer. Asbestos is the generic, industrial name for a group of six minerals determined by common size and inherent physical properties. Crocidolite, amosite, anthophyllite, tremolite and actinolite are all asbestos minerals from the amphibole mineral group. The sixth mineral, chrysotile, is a mineral from the serpentine mineral group. Asbestos fibres are particles longer than, or equal to, five μm with a length to width ratio greater than or equal to 3:1; however, the ratio can be higher than 20 or even 1000. They are inflammable, thermally stable, resistant to biodegradation, chemically inert to most chemicals and have low electrical conductivity. Because of these attributes, asbestos was heartily embraced in industrial production.Different methods are used to determine the type and quantity of asbestos fibres in the air. Some of the most common methods and instruments are: polarizing light microscopy (PLM), phase contrast optical microscopy (PCM), scanning electron microscopy (SEM), analysis with electron diffraction spectra (SAED) with energy dispersive X-ray analysis (EDS), powder X-ray diffraction technique (XRD), and transmission electron microscopy (TEM). Some of above-mentioned methods (PCM, PLM, XRD) are currently popular due to their low cost, but using these methods exclusively could lead to false estimates of asbestos levels. It is hard to distinguish asbestos fibres from certain other fibres like artifacts, organic or inorganic. Therefore, it is important to observe not only the habit of minerals, but also the chemical composition of them. A combination of SEM and EDS gives information about both the habit and the chemical composition of the observed fibers, and so is suitable for asbestos analysis. Different methods of analysis are displayed and compared in this paper. Analyses were made using SEM with EDS and XRD. All samples were collected in working areas of a factory which used asbestos in production. Presence of different types of asbestos was confirmed.

The gross calorific value (GCV) or heating value of a sample of fuel is one of the important properties which defines the energy of the fuel. Many researchers have proposed empirical formulas for estimating GCV value of coal. There are some known methods like Bomb Calorimeter for determining the GCV in the laboratory. But these methods are cumbersome, costly and time consuming. In this paper, multivariate regression analysis and Co-active neuro-fuzzy inference system (CANFIS) backed by genetic algorithm technique is used for the prediction of GCV, taking all the major constituents of the proximate and ultimate analyses properties as input parameters and the suitability of one technique over the other has been proposed based on the results. Correlations have been developed using multivariate regression analysis that are simple to use based on the proximate and ultimate analysis of data sets from 25 different states of USA because a very through study has been done and the data available is less variable. Also, CANFIS backed by genetic algorithm model is designed to predict the GCV of 4540 US coal samples from the abovementioned datasets. Optimization of the network architecture is done using a systematic approach (genetic algorithm). The network was trained with 4371, cross validation with 100, predicted with rest 69 datasets and the predicted results were compared with the observed values. The mean average percentage error in prediction is found to be negligible (0.2913%) and the generalization capability of the model was established to be excellent. A useful concept of sensitivity analysis is adopted to set the hierarchy of influence of input factors. The results of the present investigation provide functional and vital information for prediction of GCV of any type of coal in USA.

The offered approach is based on the establishment of the functional dependence between river water discharge (Q) and suspended ms, in a number of observations, which noticeably differs from the mean value (R) of subsequent allocated period(s). The earliest period anthropogenic component during the subsequent period(s) is the difference between an actual suspended sediment yield and its hypothetical value, which is connected only with changes of natural (mainly, hydro-climatical) factors without any anthropogenic changes of geographical (erosive) conditions in a river basin. This hydro-climatical component is calculated by extrapolation of an me for subsequent period(s). Approbation of the offered approach is made on the examples of some rivers (Zapadny Bug (Ukraine), Magdalena (Colombia), Bei-Nan (Taiwan, China), Sanchuanhe (China) and Indus (India, Pakistan, China).

As the information carried in a high spatial resolution image is not represented by single pixels but by meaningful image objects, which include the association of multiple pixels and their mutual relations, the object based method has become one of the most commonly used strategies for the processing of high resolution imagery. This processing comprises two fundamental and critical steps towards content analysis and image understanding i.e. image segmentation and classification. This paper proposes a robust object based segmentation algorithm using multi-resolution analysis technique and object based supervised image classification using modified cloud basis functions (CBFs) neural network algorithm to identify road features from high resolution satellite remotely sensed images.

The Mesozoic Mashhad granitoid plutons have intruded into ophiolite complexes, meta-sediments and pyroclastics in the Binalood region, located SW of Mashad city in the NE part of Iran. Based on petrography and geochemistry, the Mashhad granitoids have been classified into 1) grey granite, 2) pink granite, 3) muscovite granite, 4) granodiorite and 5) pegmatite and quartz veins. Granitoids show typical igneous micro-textures with the mineral assemblage of quartz, plagioclase, K-feldspar, biotite, muscovie, amphiboles, clinopyroxene and garnet. Based on two-feldspar thermometry and hornblende-plagioclase thermometry / barometry, igneous temperatures of 750 to 770oC and pressures of 4.6 to 5.5 kbars for the emplacement of granitoids have been estimated. The granitoids of Mashhad area have been classified as moderately peraluminous, S to I type granitoids of sub-alkaline to calcic type. Fluid inclusion study on Mashhad granitoids shows the presence of Isolated Fluid Inclusions (IFI) as well as Trail Bound Inclusions (TBI). Four types of fluid inclusions viz., Type I CO2-H2O inclusions, Type II Low salinity aqueous inclusions, Type III, high salinity inclusions and Type IV Carbonic inclusions have been recorded in Mashhad granitoids. Fluid inclusions occur as rounded, oval and negative crystal shape varying in size from 5 to 16 μm. CO2-H2O fluids are the most common fluids in Mashhad granitoids. CO2 in CO2-H2O inclusions varies from 20 to 80 percent. Minor bi-phase, low salinity aqueous inclusions occur. Presence of Type III, Halite bearing fluids are found mainly in quartz veins in granodiorite. Type IV, carbonic fluids occur along late fractures which cross-cut the early Type I, CO2-H2O fluids. CO2 in CO2-H2O inclusions shows Tm around -56.8 oC, indicating almost pure carbonic inclusions. TmClath vary from 4 to 8oC. Th of CO2 in liquid phase ranges from - 9 to 22o C with densities of 0.92 to 0.68 g/cc and the total homogenization of CO2-H2O ranges from 205 to 320oC, indicating XCO2 valuesof 0.75 to 0.20 mole fraction. The bi-phase fluid inclusions show low salinity values of 4 to 8 wt. % NaCl equivalent to 1.03 to 0.96 g/cc. Type-IV, late carbonic inclusions show Th ranging from 20 to 25°C with densities from 0.82 to 0.78 g/cc. Tye III, halite bearing fluids show temperatures of melting from 315 to 335oC with salinity values of 38 to 40 wt. % NaCl equivalent. The density data of fluids in Mashhad granitoids indicates entrapment temperatures of 590 to 650oC at pressures of 4.1 to 5.2 Kbar. This data nearly coincides with the mineral P-T estimates. There are strong evidences of “fluid-present” partial melting process during the formation of S-type and I-type granitoids in Mashhad area. The low density carbonic fluids are chronologicaly late fluids trapped in granitoids, formed due to the peferential leakage of water from the early CO2-H2O inclusions. Fluid leakage is related to ductile shear deformation along thrust zones in Mashhad granitoids.

Our civilization is based on metals, among other life supports. The existing ore deposits are becoming rapidly depleted by almost exponentially increasing demand and production and major new ore discoveries are needed. Mineral exploration is supported by modern tools and scientific ideas, but geological characteristics of orebodies and their rock associations have still to be visualized.The time-tested exploration search for (near)-analogs of important model deposits is still the basic approach and it will be around for a long time, even as the future ores will be found under increasingly thick cover. The skills of visual recognition of geological features indicative of ore presence can best be gained in the field, but the second best experience comes from examination and study of the real geological materials assembled in systematically organized geological sample sets. The Lithotheque knowledge system of recording and interpreting mineral deposits is based on sets of miniaturized rock/ore samples permanently attached to rigid plates and stored like books for instant access. It has been designed to bridge the gap between written text or a lecture and a field visit with minimum demand on space and servicing. The sample images and supplementary materials are transmitted via internet. The existing Data Metallogenica and Lithotheque systems, now based in Australia, could be adopted internationally and established in a number of regional centers contributing local knowledge to global metallogeny and exchanging material. This would enhance the practical component of mineral resources education and ore finding.