strata movement and surface subsidence prediction model of dense solid backfilling mining surface subsidence is the most common disaster in coal mining areas which threatens human lives and assets in this study a prediction model is proposed to predict the surface subsidence caused by dense solid backfilling mining firstly the surface subsidence is monitored by high resolution survey and its static and dynamic characteristics are analyzed then the universal law of strata movement and load distribution on the main roof are analyzed by similar material simulation and numerical simulation respectively the strata movement and deformation of dense solid backfilling mining are totally different from caving mining there is no caving zone but a limited height of fractured zone developed in the strata the load distribution on main roof follows the piecewise function finally the prediction model is created based on the combination of elastic foundation beams and volume invariant transfer principle and the prediction values basically coincide with measured values this prediction model can provide reference data for the evaluation and management of coal mining hazards

mineralogy and geochemistry of alluvium contaminated by metal mining in the rio tinto area southwest spain the rio tinto in sw spain drains cu and pyrite mines which have been in operation since at least the bronze age extensive metal mining especially from 1873 to 1954 has resulted in contamination of the rio tinto alluvium with as cu pb ag and zn x ray diffraction xrd wavelength dispersive x ray mapping scanning electron microscope petrography and x ray energy dispersive edx analysis has revealed that 4 major groups of contaminant metal and as bearing minerals including sulphides fe as oxides fe oxides hydroxides oxyhydroxides and fe oxyhydroxysulphates occur in the alluvium sulphide minerals including pyrite chalcopyrite arsenopyrite and sphalerite occur in alluvium near the mining areas iron hydroxides and oxyhydroxides such as goethite and possibly ferrihydrite occur in cements in both the mining areas and alluvium downstream and carry minor amounts of as cu and zn iron oxyhydroxysulphates including jarosite plumbojarosite and possibly schwertmannite are the most common minerals in alluvium downstream of the mining areas and are major hosts of cu pb zn and of as next to the fe as minerals this work and other field observations suggest that 1 the extreme acidity and elevated metal concentrations of the river water will probably be maintained for some time due to oxidation of pyrite and other sulphides in the alluvium and mine waste tips and from formation of secondary oxide and oxyhydroxysulphates 2 soluble fe oxyhydroxysulphates such as copiapite which form on the alluvium are a temporary store of contaminant metals but are dissolved during periods of high rainfall or flooding releasing contaminants to the aqueous system 3 relatively insoluble fe oxyhydroxysulphates and hydroxides such as jarosite and goethite may be the major long term store of alluvial contaminant metals and 4 raising river ph will probably cause precipitation of fe oxyhydroxides and oxides hydroxides oxyhydroxides and thus have a positive effect on water quality but this action may destabilise some of these contaminant metal bearing minerals releasing metals back to the aqueous system

electromagnetic and geoelectric investigation of the gurinai structure inner mongolia nw china abstract in three field campaigns between the years 2000 and 2004 geophysical measurements were conducted in the ejina basin nw china research work in the year 2004 which is described in this paper was concentrated on the gurinai structure 101 25 e 41 n situated in the southeastern part of the ejina basin in transition to the dune fields of the badain jaran shamo on satellite images the gurinai structure can be identified by two almost 100 km long subparallel n s striking lineaments which may indicate tectonic deformations of late quaternary sediments to get a coherent picture of the structure a geophysical survey employing three electromagnetic methods magnetotellurics mt transient electromagnetics tem and geoelectrics dc has been conducted to map the subsurface resistivity at different depth scales the geophysical data interpretation for shallow and intermediate depth down to a few hundred meters links the subsurface distribution of electric resistivity to geomorphological units known from field work in reference with satellite images the westerly lineament of the gurinai structure coincides with a subvertical change in electric resistivity together with geomorphological indications from fieldwork and the analysis of elevation data srtm a tectonic deformation of unconsolidated sediments along a fault with an extensional component is interpreted in the central and eastern part of the gurinai structure a shallow resistive subsurface layer can be traced into the first dunes of the badain jaran shamo this resistive subsurface layer is linked to the presence of fresh water indicating infiltration from the dune field also in the eastern part of the gurinai structure a resistive approximately ene striking feature can be seen at intermediate depth which is interpreted as a crystalline basement ridge towards the southern margin of the gurinai structure a trough shaped unit with low resistivities and a thickness of about 1 km is identified and can be explained by a sediment package saturated with fluids of high salinity or substantial amounts of clay the strike direction of the structure can be connected to the regional pattern of tectonic faults and seismicity the interpretation of electromagnetic data at various depth scales contributes to the general understanding of the ejina basin s buildup and tectonic setting in the vicinity of the gurinai structure

gravity data as a tool for landfill study this paper shows the potential of gravity data to map a buried landfill bottom topography to this end a gravity inversion method is presented for estimating the landfill s bottom depths at discrete points assuming a decrease of the density contrast with depth according to a hyperbolic law the method s efficiency was tested using synthetic data from simulated waste landfills producing estimated bottom topographies very close to the true ones the method s potentiality has been further evaluated in applying it to the gravity data from the abandoned thomas farm landfill site indiana usa whose bottom topography is known the estimated topography showed close agreement with the known thomas farm landfill s bottom topography

effect of coal mining activities on the environment of tetraena mongolica in wuhai inner mongolia china a geochemical perspective abstract the main objective of this study is to investigate the geochemical impact of gob piles on the environment of tetraena mongolica a chinese nationally protected plant twenty five major and trace elements in samples of soil gangue roof and floor of coal seams collected from wuhai inner mongolia china were analyzed by atomic fluorescence spectrometry afs x ray fluorescence xrf and inductively coupled plasma mass spectrometry icp ms the results show that the elements such as cu pb mo and as were highly enriched in soil coal and coal gangue between 2003 and 2012 heavy metal concentrations had increased in soil due to mining activities leaching and volatilization are the two main pathways that gob piles affect the environment with the leaching range of the gob piles extending about 0 10 m while the range for volatilization is 3 5 km the concentration of cu pb mo and as in t mongolica also shows a positive correlation with the elemental compositions of the roof and floor of the coal seam and adult individuals have a higher correlation than juveniles therefore the distribution of coal resources and the local geology contribute to the restricted range of t mongolica in wuhai

integration of 3d geological modeling and gravity surveys for geothermal prospection in an alpine region abstract thermal sources are common manifestations of geothermal energy resources in alpine regions the up flow of the fluid is well known to be often linked to cross cutting fault zones providing a significant volume of fractures since conventional exploration methods are challenging in such areas of high topography and complicated logistics 3d geological modeling based on structural investigation becomes a useful tool for assessing the overall geology of the investigated sites geological modeling alone is however less effective if not integrated with deep subsurface investigations that could provide a first order information on geological boundaries and an imaging of geological structures with this aim in the present paper the combined use of 3d geological modeling and gravity surveys for geothermal prospection of a hydrothermal area in the western alps was carried out on two sites located in the argentera massif nw italy the geothermal activity of the area is revealed by thermal anomalies with surface evidences such as hot springs at temperatures up to 70 c integration of gravity measurements and 3d modeling investigates the potential of this approach in the context of geothermal exploration in alpine regions where a very complex geological and structural setting is expected the approach used in the present work is based on the comparison between the observed gravity and the gravity effect of the 3d geological models in order to enhance local effects related to the geothermal system it is shown that a correct integration of 3d modeling and detailed geophysical survey could allow a better characterization of geological structures involved in geothermal fluids circulation particularly gravity inversions have successfully delineated the continuity in depth of low density structures such as faults and fractured bands observed at the surface and have been of great help in improving the overall geological model

mineralogical and geochemical characterisation of open air tailing and waste rock dumps from the libiola fe cu sulphide mine eastern liguria italy active acid mine drainage amd processes at the libiola fe cu sulphides mine are mainly triggered by water rock interaction occurring within open air tailing and waste rock dumps these processes are mainly controlled by exposure to weathering agents the grain size of the dumped materials and by the quantity of sulphides the sulphide types and their mode of occurrence due to these factors several paragenetic stages of evolution have been recognised at different depths at different sites and within the same site the dump samples were investigated with mineralogical reflected and transmitted light optical microscopy xrpd and sem eds and geochemical icp aes leco techniques the amd evaluation of the tailing and waste rock samples was performed by calculating the maximum potential acidity the acid neutralising capacity and the net acid producing potential the results allowed us to demonstrate that the open air tailings had already superseded their amd apex and are now practically inert material composed mainly of stable goethite lepidocrocite hematite assemblages on the contrary the sulphide rich waste rocks still have a strong potential to produce long term amd causing the acidification of circulating waters and the release of several hazardous elements

textural control on gold distribution in as free pyrite from the dongping huangtuliang and hougou gold deposits north china craton hebei province china article i nfo pyrite from the dongping huangtuliang and hougou gold deposits hebei province china was investigated using a combination of ore microscopy including back scattered imaging and in situ laser ablation inductively coupled plasma mass spectroscopy la icp ms a range of elements including au te ag pb bi cu co ni and as was analyzed with the aim to constrain the textural controls and influence of superimposed deformation on the distribution of invisible gold in as free pyrite thedatasetshowsexcellentcorrespondence betweenmeasuredhighgoldvaluesandthreekeytexturalcriteria i areasofclusteredtellurideinclusions especiallyindongping ii microshearingandfracturing brecciation dongping and huangtuliang and iii pyrite recrystallization huangtuliang invisible gold is only at trace levels in the hougou and gold bearing telluride minerals are not observed this is considered to result from larger scale remobilization of gold during advanced brecciation and recrystallization of pyrite pyrite grains containing clustered inclusions have by far the highest gold concentrations up to 1 wt with consistent values of thousands of ppm au interpretation of textures and la icp ms data infers that in these areas the distribution of telluride inclusions extends pervasively from micron to nanoscale i e as fields of nanoparticles local employment of coupled dissolution reprecipitation reaction between pyrite and fluids driving the k metasomatic alteration dated at 150 ma is invoked to explain such patterns syn deformational grain scale mobilization of gold and other elements took place leading to a portion of the gold being recrystallized within fractures and microshears the deformational event leads to gold enrichment in the huangtuliang pyrite where brittle fracturing brecciation has been followed by a resorption and recrystallization in the latter case foam textured pyrites again without as can contain up to hundreds of ppm gold theinterpreted sequenceof pyritepost depositional eventsis inaccordancewith the protracted magmaticevolution of the area starting with variscan alkaline intrusions 390 ma and reactivated during the yanshanian orogeny 150 ma thestudyshows i thatas freepyritecanreadilycontainsignificantamountsofinvisiblegold bothasnanoparticles

integrated method of rs and gpr for monitoring the changes in the soil moisture and groundwater environment due to underground coal mining mining affects the environment in different ways depending on the physical context in which the mining occurs in mining areas with an arid environment mining affects plants growth by changing the amount of available water this paper discusses the effects of mining on two important determinants of plant growth soil moisture and groundwater table gwt which were investigated using an integrated approach involving a field sampling investigation with remote sensing rs and ground penetrating radar gpr to calculate and map the distribution of soil moisture for a target area we initially analyzed four models for regression analysis between soil moisture and apparent thermal inertia and finally selected a linear model for modeling the soil moisture at a depth 10 cm the relative error of the modeled soil moisture was about 6 3 and correlation coefficient 0 7794 a comparison of mined and unmined areas based on the results of limited field sampling tests or rs monitoring of landsat 5 thermatic mapping tm data indicated that soil moisture did not undergo remarkable changes following mining this result indicates that mining does not have an effect on soil moisture in the shendong coal mining area the coverage of vegetation in 2005 was compared with that in 1995 by means of the normalized difference vegetation index ndvi deduced from tm data and the results showed that the coverage of vegetation in shendong coal mining area has improved greatly since 1995 because of policy input rmb 0 4 per ton coal production by shendong coal mining company the factor most affected by coal mining was gwt which dropped from a depth of 35 41 m before mining to a depth of 43 38 m after mining at the bulianta coal mine based on water well measurements ground penetrating radar at frequencies of 25 and 50 mhz revealed that the deepest gwt was at about 43 4 m there was a weak water linkage between the unsaturated zone and groundwater and the decline of water table primarily resulted from the well pumping for mining safety rather than the movement of cracking strata this result is in agreement with the measurements of the water wells the roots of nine typical plants in the study area were investigated populus was found to have the deepest root system with a depth of about 26 m based on an assessment of plant growth demands and the effect of mining on environmental factors we concluded that mining will have less of an effect on plant growth at those sites where the primary gwt depth before mining was deep enough to be unavailable to plants if the primary gwt was available for plant growth before mining especially to those plants with deeper roots mining will have a significant effect on the growth of plants and the mechanism of this effect will include the loss of water to roots and damage to the root system

anisotropy induction logging the apparent tensor anisotropic conductivity of the formations around a borehole can be calculated from triaxial induction logging data in particular analysis of the late time transient coupling of triaxial coincident loops yields a simple method to determine the principle axes and conductivities

electrical resistivity tomography applied to geologic hydrogeologic and engineering investigations at a former waste disposal site a former dolerite quarry and landfill site was investigated using 2d and 3d electrical resistivity tomography ert with the aims of determining buried quarry geometry mapping bedrock contamination arising from the landfill and characterizing site geology resistivity data were collected from a network of intersecting survey lines using a wenner based array configuration inversion of the data was carried out using 2d and 3d regularized least squares optimization methods with robust l1 norm model constraints for this site where high resistivity contrasts were present robust model constraints produced a more accurate recovery of subsurface structures when compared to the use of smooth l2 norm constraints integrated 3d spatial analysis of the ert and conventional site investigation data proved in this case a highly effective means of characterizing the landfill and its environs the 3d resistivity model was successfully used to confirm the position of the landfill boundaries which appeared as electrically well defined features that corresponded extremely closely to both historic maps and intrusive site investigation data a potential zone of leachate migration from the landfill was identified from the electrical models the location of this zone was consistent with the predicted direction of groundwater flow across the site unquarried areas of a dolerite sill were imaged as a resistive sheet like feature while the fault zone appeared in the 2d resistivity model as a dipping structure defined by contrasting bedrock resistivities

shallow seismic reflection study of a glaciated valley shallow seismic reflection data were recorded along two long 1 6 km intersecting profiles in the glaciated suhre valley of northern switzerland appropriate choice of source and receiver parameters resulted in a high fold 36 48 data set with common midpoints every 1 25 m as for many shallow seismic reflection data sets upper portions of the shot gathers were contaminated with high amplitude source generated noise e g direct refracted guided surface and airwaves spectral balancing was effective in significantly increasing the strength of the reflected signals relative to the source generated noise and application of carefully selected top mutes ensured guided phases were not misprocessed and misinterpreted as reflections resultant processed sections were characterized by distributions of distinct seismic reflection patterns or facies that were bounded by quasi continuous reflection zones the uppermost reflection zone at 20 to 50 ms 15 to 40 m depth originated from a boundary between

geoelectrical measurements at the tag hydrothermal mound direct current electrical experiments with electrode arrays deployed by a submersible alvin were used to determine the resistivity structure of the seafloor below and vertical potential gradients in sea water above the hydrothermally active tag mound apparent resistivities of the sulfides at shallow depths 10 m below seafloor over the mound ranged between 0 18 0 21 ohm m compared to nearby basalt pillow apparent resistivities of 2 1 2 4 ohm m the potential differences between heights of about 18 to 27 m above the mound averaged 3 7 mv voltage increasing with height with variations between about 2 9 and 12 7 mv

results of 2 and 3 d high resolution seismic reflection surveying of surficial sediments to investigate the potential of seismic reflection methods for studying surficial sediments 2 and 3 d high resolution surveys have been conducted across a plot of land adjacent to a landfill in northern switzerland results of the reflection profiling demonstrated that closely spaced common reflection points 2 5 m and high fold 12 data were prerequisites for producing clear images at this site for the 3 d survey an area of 115 160 m was covered with common reflection points every 2 5 2 5 m three dimensional migration of the resultant 18 to 70 fold data proved to be a critical step in correctly locating out of plane reflections and collapsing diffractions that were prominent features in the 2 d profile data within the 3 d data volume a conspicuous reflective zone and a marked decrease in reflection amplitudes at 200 m depth delineates the bedrock surface immediately above this level are continuous reflections from flat lying lacustrine sediments these are in turn overlain by regions of strong reflected energy interpreted as either large erratic blocks anomalous compaction zones or gravel channels lenses

hydrochemical characterization of acute acid mine drainage at iron duke mine mazowe zimbabwe acid mine drainage amd with a minimum ph of 0 52 was recorded at iron duke mine near mazowe zimbabwe during an investigation of the environmental geochemistry of mine waters in the greenstone belts of zimbabwe hydrochemical data for waters emanating from the iron duke waste rock pile indicate their super saturation with respect to fe and so42 extremely high dissolved concentrations of al zn cu co ni v cr cd and as also prevail substantial losses of metals from solution occur within 400 m of the amd source through the precipitation of crystalline sulphates principally melanterite further downstream hydrous oxide precipitation forms the dominant mechanism of metal attenuation in waters characteristically under saturated with respect to fe sulphates speciation and saturation index data generated using the equilibrium model wateq4f suggest that such codes have broad utility for generic prediction of the mineralogical contraints on metal mobility in acute amd systems major discrepancies between modelled and empirical hydrochemistries are however evident for super saturated waters in which the kinetics of fe precipitation are slow and in which total ionic strengths markedly exceed their theoretical maximum

first results of the moses experiment sea sediment conductivity and thickness determination bute inlet british columbia by magnetometric offshore electrical sounding a static electrical method has been developed to determine the electrical resistivity of crustal rock beneath the sea the transmitter is a vertical long wire bipole extending from the sea surface to the sea floor a commutated current generated on the ship is fed to two large electrodes one near the sea surface the other at the end of a long insulated wire the return path for the current is through the sea and the subjacent crust the receiver is a self contained remote microprocessor controlled magnetometer which is deployed from the ship to the sea floor and subsequently recovered the data are measurements of the azimuthal component of the magnetic field as a function of transmitter receiver horizontal separation the acronym moses has been coined for the method the choice of the name moses is appropriate because the system geometry is carefully arranged to remove many of the adverse effects of the relatively conductive sea water in particular accurate estimates of sea floor resistivity ar

on coincident loop transient electromagnetic induction logging abstractcoincident loop transient induction wireline logging is examined as the borehole analog of the well known land and airborne time domain electromagnetic em method the concept of whole space late time apparent resistivity is modified from the half space version commonly used in land and airborne geophysics and applied to the coincident loop voltages produced from various formation borehole and invasion models given typical tool diameters off time measurements with such an instrument must be made on the order of nanoseconds to microseconds much more rapidly than for surface methods departure curves of the apparent resistivity for thin beds calculated using an algorithm developed to model the transient response of a loop in a multilayered earth indicate that the depth of investigation scales with the bed thickness modeled resistivity logs are comparable in accuracy and resolution with standard frequency domain focused induction logs however if measurement times are longer than a few mic

a mineralogical and geochemical study of element mobility in sulfide mine tailings of fe oxide cu au deposits from the punta del cobre belt northern chile two flotation tailings sites ojancos and p cerda from the fe oxide cu au punta del cobre belt south of copiapo atacama desert northern chile are geochemically largely using sequential extractions and mineralogically compared main ore minerals are pyrite magnetite and or hematite and chalcopyrite gangue is dominantly calcite with minor quartz the host silicate assemblage is largely controlled by hydrothermal alteration and consists of variable amounts of the following minerals k feldspar ca amphibole biotite sericite chlorite tourmaline epidote quartz in this study both the ojancos and the p cerda tailings were deposited in valley dam impoundments and when they were filled new tailings were deposited upstream as a result high quantities of seepage migrated downstream into the older tailings impoundment at ojancos the recent upstream tailings have excess of acid potential 7 1 wt calcite and 3 5 wt pyrite whereas the older downstream tailings are characterized by alternations of several meter thick intervals with high neutralizing potential about 40 wt calcite and 2 wt pyrite and intervals with high acid potential about 3 wt calcite and 4 wt pyrite acid mine drainage amd with the precipitation of schwertmannite ph 3 15 and chalcoalumite ph 4 9 flows out at the interface between the uphill and downstream tailings strong downstream element transport is taking place and contributes to the formation of the cementation zone mainly gypsum ferrihydrite and goethite and locally jarosite in the older downstream impoundment the cementation zone ph 4 shows strong enrichment of heavy metals e g up to 6800 ppm cu 680 ppm zn 1100 ppm as mainly adsorbed and as secondary sulfides e g covellite in contrast at the p cerda tailings impoundment carbonates are homogeneously distributed and the overall neutralization potential exceeds the acid potential average of about 10 wt calcite and up to 2 5 wt pyrite the up to 5 m thick oxidation zones paste ph 6 9 8 3 at p cerda are characterized by interlayering of coarser dark gray unoxidized layers with fine grained fe iii hydroxide rich ochre to red brown colored horizons the hyperarid climate dries out first the coarse sulfide rich horizons of the tailings and limits so the oxidation which is restricted to the fine grained due to their higher moisture retention capacity however results indicate that during operation an important element transfer from the younger upstream tailings to the older downstream tailings impoundment took place possibly by sorptive transport at ferric polymers or colloids in the form of neutral mine drainage nmd this would explain the metal enrichments in the cementation zone which are mainly associated to the exchangeable fraction and not as secondary sulfides this results in both cases in ojancos mainly as amd and in p cerda mainly as nmd in fe iii input as ferric cation as ferric polymer or co3 complexes to the downstream impoundment this constitutes a very effective acid potential transfer to the older downstream material because oxidation via input of external fe iii produces 16 mol of protons per mol fes2 i e eight times more than via oxidation with oxygen in addition the created acidity favors dissolution of the abundant fe oxides magnetite and hematite of this ore deposit type providing so additional fe iii for sulfide oxidation

the influences of mining subsidence on the ecological environment and public infrastructure a case study at the haolaigou iron ore mine in baotou china the scope and extent of mine subsidence caused by exploitation of metal ores are usually low however in some cases owing to such factors as special geological conditions in ore body backward mining technology and unsound management systems exploitation of metal ores would also lead to a large area of mine subsidence causing great damages to the mining environment and infrastructure a serious mine subsidence happened in january 2007 at the haolaigou iron ore mine has caused a huge collapse pit on the earth s surfaces this provides a suitable place to study the influence of mine subsidence based on former research results a 3d geological model is constructed using the rock model software developed by authors group based on in situ geological conditions the range of orebody mining and the physical and mechanical parameters of rock and soil mass were determined by inverse analysis creep analysis of the collapse pit was also performed furthermore the elastoplastic and creep of the secondary collapse were computed and the final range of the collapse pit was predicted finally the influences of mining subsidence on the ecological environment and public infrastructure are discussed and control measures were proposed the results indicate that the collapse pit would not affect the road even if creep is considered however the secondary collapse would influence the road so the collapse pit should be dealt with as soon as possible

marine dipole dipole controlled source electromagnetic and coincident loop transient electromagnetic experiments to detect seafloor massive sulphides effects of three dimensional bathymetry seafloor massive sulphides smss are regarded as a potential future resource to satisfy the growing global demand of metals including copper zinc and gold aside from mining and retrieving profitable amounts of massive sulphides from the seafloor the present challenge is to detect and delineate significant sms accumulations which are generally located near mid ocean ridges and along submarine volcanic arc and backarc spreading centres currently several geophysical technologies are being developed to detect and quantify sms occurrences that often exhibit measurable contrasts in their physical parameters compared to the surrounding host rock here we use a short fixed offset controlled source electromagnetic csem system and a coincident loop transient electromagnetic tem system which in theory allow the detection of sms in the shallow seafloor due to a significant electrical conductivity contrast to their surroundings in 2016 csem and tem experiments were carried out at several locations near the trans atlantic geotraverse hydrothermal field to investigate shallow occurrences of massive sulphides below the seafloor measurements were conducted in an area that contains distinct sms sites located several kilometres off axis from the mid atlantic ridge some of which are still connected to hydrothermal activity and others where hydrothermal activity has ceased based on the quality of the acquired data both experiments were operationally successful however the data analysis indicates bias caused by three dimensional 3d effects of the rough bathymetry in the study area and thus data interpretation remains challenging therefore we study the influence of 3d bathymetry for marine csem and tem experiments focusing on shallow 3d conductors located beneath mound like structures we analyse synthetic inversion models for attributes associated with 3d distortions of csem and tem data that are not sufficiently accounted for in conventional 1d tem and 2d csem interpretation schemes before an adequate quantification of sms in the region is feasible these 3d effects need to be studied to avoid over underestimation of sms using the acquired em data the sensitivity of csem and tem to bathymetry is investigated by means of 3d forward modelling followed by 1d tem and 2d csem inversion of the synthetic data using realistic error conditions subsequently inversion models of the synthetic 3d data are analysed and compared to models derived from the measured data to illustrate that 3d distortions are evident in the recorded data sets

mineralogical and geochemical investigations of pyrite rich mine waste from a kyanite mine in central virginia with comments on recycling a pyrite rich waste stream is one of three types generated from a kyanite mine in central virginia near the town of dillwyn buckingham county currently ore consists of approximately 3 pyrite waste and an estimated 382 000 tons of this waste stream has been generated over the past 60 years the mineralogy of the waste stream consists of variable amounts of pyrite 70 99 talc 1 20 quartz 1 10 kyanite 0 5 5 with minor or trace amounts of magnetite hematite galena anorthite and rare earth phosphate energy dispersive spectroscopy analysis indicates that talc has minor amounts of al up to 1 57 wt and fe up to 4 29 wt and pyrite grains have no impurities above detection limit of approximately 0 1 wt bulk chemical analysis of selected elements using inductively coupled plasma mass spectrometry analysis indicate that zn 28 82 367 71 ppm as 8 94 18 26 ppm se 44 62 64 50 ppm cd 0 19 1 03 ppm hg 0 87 35 91 ppm and pb 65 10 189 66 ppm occur at levels of some environmental concern au and ag concentrations are negligible currently the waste stream is well managed and sold but for a low price talc is of sufficient quality to be of interest for recycling but the estimated 540 tons generated per year is not a suitable quantity to be economically viable currently the waste stream is not viable for recycling for higher monetary value however the characteristics of the pyrite may enable such recycling in the future for solar energy technologies this and other associated waste streams show long term promise for integrated recycling and may play important economic roles in an economically disadvantaged region

stream water geochemistry from mine wastes in pena de hierro riotinto area sw spain a case of extreme acid mine drainage in this work we have studied the geochemistry of stream waters arising from waste dumps at the pena de hierro mine iberian pyrite belt sw spain and we have correlated them with the mineralogical and geochemical characteristics of the wastes to asses the source and factors affecting the release of trace elements the mineralogical composition and geochemistry of 58 borehole samples of waste dumps were studied in the 2 mm fraction twenty eight water samples collected in winter and summer from streams emerging from the waste dumps were analysed for ph eh conductivity temperature sulphates and major and trace elements the leachates from pyrite rich volcanic tuffs produced very acidic waters usually with phs below 2 and reaching values as low as 0 7 the partial dissolution of gossan which is mainly composed of fe oxy hydroxides and is rich in trace elements released high concentrations of fetot up to 33 g l as up to 72 mo up to 11 mg l on the other hand cd zn and pb reached up to 0 85 142 and 0 42 mg l respectively in the stream arising from roasted pyrite ashes and other pyritic wastes several elements such as al fe as co cu and mo were strongly correlated with the ph but cd and zn were not correlated under such acidic conditions the precipitation of jarosite seems to be an important factor in the retention of pb the mobility sequence of trace elements shows that co zn and cd were among the most mobile elements cu as and mo had intermediate mobility and pb was the most immobile this work shows that uncontrolled waste dumping increases the pollution potential and a selective management could reduce the release of trace elements into stream waters and mitigate the contamination

estimation of potential pollution of waste mining dumps at pena del hierro pyrite belt sw spain as a base for future mitigation actions abstract pena del hierro is an abandoned mine site located in the catchment area of the tinto river pyrite belt sw spain as leaching from the spoils affect the quality of the stream water the waste dumps have been characterized for mineralogy geochemistry and granulometry to obtain an estimate of the potential pollution waste rock dumps in pena del hierro are very heterogeneous and are mainly composed of acid volcanic tuffs gossan shales roasted pyrite ashes floated pyrite the volcanic tuffs the gossan and the shales coexist in the same piles the roasted pyrite ashes and the floated pyrite form more homogeneous dumps the dissolution of pyrite concentrated in pyrite ashes and floated pyrite units can generate acid mine drainage nevertheless acid volcanic tuffs which are rich in pyrite and have no neutralizing minerals are the main source of these acidic effluents only muscovite might partially neutralize the acidity but the dissolution of this mineral is too slow to compensate for acidity the occurrence of jarosite in the

environmentally sustainable mining a case study on surface subsidence control of grouting into overburden this paper presents an investigation on the effect of grouting into multi bed separation to control mining induced surface subsidence in the overburden without obvious thick and hard strata for generating large scale bed separation overburden grouting is carried out by increasing the number of boreholes and grouting strata the scale model test numerical simulation and field measurements are used to study distribution and process of bed separation and to compare the overburden failure with surface subsidence due to pre and post overburden grouting with a case study of the qi nan coal mine anhui province china the scale model test and numerical simulation results of the overburden grouting process are in close agreement with those obtained from the field measurements filling masses with different diffusion radii are commonly formed in the different bed separation which are overlaid to control the surface subsidence it is proven that overburden grouting can successfully mitigate overburden failure and subsidence without obvious hard strata and bed separations this provides an effective and cost efficient approach for addressing the surface subsidence and overburden deformation problems due to mining

optimized fast hankel transform filters in the linear digital filter theory for calculation of hankel transforms it is possible to find explicit series expansions for the filter coefficients a method is presented for optimizing the hankel filters calculated in this way for a certain desired accuracy of computation the sampling density and filter length are minimized by choosing the parameters determining the filter characteristics according to the analytical properties of the input function a new approach to the calculation of the filter coefficients has been developed for these optimized filters the length of the filters may be further reduced by introducing a shift in the sampling scheme

simultaneous 3d depth to basement and density contrast estimates using gravity data and depth control at few points we have developed a gravity inversion method for simultaneouslyestimatingthe3dbasementreliefofasedimentary basin and the parameters defining a presumed parabolic decay of the density contrast with depth in a sedimentary pack assumingpriorknowledgeaboutthebasementdepthatafew points thesedimentarypackisapproximatedbyagridof3d vertical prisms juxtaposed in both horizontal directions of a right handed coordinate system the prisms thicknesses representthedepthstothebasementandaretheparametersto be estimated from the gravity data to estimate the parameters defining the parabolic decay of the density contrast with depthandtoproducestabledepth to basementestimates we imposed smoothness on the basement depths and proximity between estimated and known depths at boreholes we applied our method to synthetic data from a simulated complex 3d basement relief with two sedimentary sections having distinct parabolic laws describing the density contrast variationwithdepth theresultsprovidegoodestimatesofthetrue parameters of the parabolic law of density contrast decay with depth and of the basement relief inverting the gravity data from the onshore and part of the shallow offshore almadabasinonbrazil snortheasterncoastshowsgoodcorrelationwithknownstructuralfeatures

long term time lapse microgravity and geotechnical monitoring of relict salt mines marston cheshire u k the area around the town of northwich in cheshire u k has a long history of catastrophic ground subsidence caused by a combination of natural dissolution and collapsing abandoned mine workings within the underlying triassic halite bedrock geology in the village of marston the trent and mersey canal crosses several abandoned salt mine workings and previously subsiding areas the canal being breached by a catastrophic subsidence event in 1953 this canal section is the focus of a long term monitoring study by conventional geotechnical topographic and microgravity surveys results of 20 years of topographic time lapse surveys indicate specific areas of local subsidence that could not be predicted by available site and mine abandonment plan and shaft data subsidence has subsequently necessitated four phases of temporary canal bank remediation ten years of microgravity time lapse data have recorded major deepening negative anomalies in specific sections that correlate with topographic data gravity 2d modeling using available site data found upwardly propagating voids and associated collapse material produced a good match with observed microgravity data intrusive investigations have confirmed a void at the major anomaly the advantages of undertaking such long term studies for near surface geophysicists geotechnical engineers and researchers working in other application areas are discussed

distribution isotopic variation and origin of sulfur in coals in the wuda coalfield inner mongolia china abstract this paper describes coal petrographic characteristics sulfur abundance distribution and isotopic signature in coals in the wuda coalfield inner mongolia northern china petrographic studies suggest that depositional environment influences petrographic composition the no 9 and no 10 coal seams which are thought to have formed on a tidal delta plain have high collodetrinite contents up to 66 1 indicating enhanced gelification and bacteria activity during coal accumulation and also have the highest sulfur content 3 46 and 3 42 both organic and pyritic sulfur isotope values 12 3 to 5 8 and 18 7 to 1 1 respectively are variable and generally tend to be more negative in high sulfur coals than those in low sulfur coals in the wuda coalfield the negative sulfur isotope values indicate that a large portion of sulfur in the high sulfur coals has a bacterial origin sulfur isotopic compositions and variations within the section were used to propose a model to explain the origin of sulfur in these coals the presence of pyritized rod like bacteria cyanophyte s gelatinous sheaths and degraded algae organic matter suggests that bacteria and perhaps algae may play an important role in the formation of these high sulfur coals

mineralogy and geochemistry of trace metals and ree in volcanic massive sulfide host rocks stream sediments stream waters and acid mine drainage from the lousal mine area iberian pyrite belt portugal abstract acid mine drainage represents a major source of water pollution in the lousal area the concentrations of trace metals and the rare earth elements ree in the host rocks stream sediment surface waters and acid mine drainage amd associated with abandoned mine adits and tailings impoundments were determined in order to fingerprint their sources and to understand their mobility and water rock interaction the results show that the fe so4 rich acid waters vary substantially in composition both spatially and seasonally these waters include very low ph mostly in the range 1 9 3 0 extreme so4 concentrations 4635 20 070 mg l 1 so 4 2 high metal contents fe al cu zn and mn and very high ree contents the trace metal concentrations decrease downstream from the discharge points either due to precipitation of neoformed phases or to dilution the north american shale composite nasc normalized patterns corresponding to sediment from one stream corona stream show a flat tendency or are slightly enriched in light ree lree the nasc normalized patterns corresponding to acidic mine waters show enrichment in the middle ree mree with respect to the lree and heavy ree hree moreover the ree concentrations in acidic mine waters are 2 or 3 orders of magnitude higher than those of the surface waters changes of ree concentrations and variation of eu anomaly show two spatially distinct patterns a pond and spring waters with higher ree concentrations ranging from 375 to 2870 g l 1 that records conspicuous negative eu anomaly and b seeps from tailings impoundments corresponding to lower ree concentrations than the first pattern ranging from 350 to 1139 g l 1 with typically negative eu anomaly the stream water samples collected from the impacted stream during the spring show a low ph 2 8 3 1 and contain high concentrations of fe and trace elements up to 61 mg l 1 also temporal variations of the ree concentrations were observed in the corona waters the results obtained show that the ree concentrations increase during the winter spring transition stream waters draining the lousal mine area show high ree concentrations reaching a maximum value of about 2846 g l 1 spring the mree concentrations are usually enriched with respect to both the lree and hree a decrease in ree concentrations and a ph increase from 3 to 6 was observed downstream of the confluence of a tributary stream the geochemistry of the waters strongly influenced the mineralogy and geochemistry of efflorescent sulfates precipitated on the banks of the streams polluted by amd the mineralogy is dominated by hexahydrite rozenite szomolnokite alunite gypsum halotrychite coquimbite copiapite and schwertmannite the ree concentrations determined in the efflorescent sulfates suggest a selective partitioning of the hree onto mg al oxyhydroxides

surface analysis of pyrite in the no 9 coal seam wuda coalfield inner mongolia china using high resolution time of flight secondary ion mass spectrometry abstract the chemical composition of pyrite in coal can be used to investigate its geological and mineralogical origin in this paper high resolution time of flight secondary ion mass spectrometry tof sims was used to study the chemical composition of various pyrite forms in the no 9 coal seam st d 3 46 from the wuda coalfield inner mongolia northern china these include bacteriogenic framboidal massive cell filling fracture filling and nodular pyrites in addition to fe 54fe 56fe 57fe other fragment ions were detected in bacteriogenic pyrites such as 27al si 28si 29si 30si 40ca cu 63cu 65cu zn 64zn 66zn 67zn 68zn ni 58ni 60ni 62ni and c3h7 tof sims images show bacteriogenic pyrites are relatively rich in cu zn and ni suggesting that bacteria probably play an important role in the enrichment of cu zn and ni during their formation intense positive secondary ion fragments from framboidal aggregates such as 27al 28si 29si alo ch2 c3h3 c3h5 and c4h7 indicate that formation of the framboidal aggregates may have occurred together with clay mineral and organic matter which probably serve as the binding substance the intense ions of 28si and 27al from massive pyrites also suggest that their pores incorporated clay minerals during crystallization together with the lowest 28si 23na value the intense organic positive secondary ion peaks from cell filling pyrites such as c3h3 c3h5 c3h7 and c4h7 indicate that pyrite formation may have accompanied dissolution or disintegration of the cell the intense p peak was observed only in the fracture filling pyrite and the highest 28si 23na value of fracture filling pyrite reflects its epigenetic origin together with xrd and rees data the stronger 40ca in nodular pyrite than other pyrite forms shows seawater influence during its formation

on mapping seafloor mineral deposits with central loop transient electromagnetics electromagnetic methods are commonly employed in exploration for land based mineral deposits a suite of airborne land and borehole electromagnetic techniques consisting of different coil and dipole configurations have been developed over the last few decades for this purpose in contrast although the commercial value of marine mineral deposits has been recognized for decades the development of suitable marine electromagnetic methods for mineral exploration at sea is still in its infancy one particularly interesting electromagnetic method which could be used to image a mineral deposit on the ocean floor is the central loop configuration central loop systems consist of concentric transmitting and receiving loops of wire while these types of systems are frequently used in land based or airborne surveys to our knowledge neither system has been used for marine mineral exploration the advantages of using central loop systems at sea are twofold 1 simplified navigation because the transmitter and receiver are concentric and 2 simplified operation because only one compact unit must be deployed we produced layered seafloor type curves for two particular types of central loop methods the in loop and coincident loop configurations in particular we consider models inspired by real marine mineral exploration scenarios consisting of overburdens 0 to 5 m thick overlying a conductive ore body 5 to 30 m thick modeling and resolution analyses showed that using a 50 m 2 transmitting loop with 20 a of current these two configurations are useful tools to determine the overburden depth to a conductive ore deposit and its thickness in the most extreme case absolute voltage errors on the order of 10 nv are required to resolve the base of a 30 m thick ore deposit whether such noise floors can be achieved in real marine environments remains to be seen

dc resistivity mapping of internal landfill structures two pre excavation surveys geophysical investigations using 2 d dc resistivity were carried out on old parts of two similar landfills with waste of different ages the data sets which included high data density in both vertical and horizontal directions were interpreted with 2 d smoothness constrained inversion the landfills were excavated after the surveying the objective was to test the capability of the resistivity method as a pre characterization technique the objectives were only partially fulfilled first the moisture content was the parameter that appeared to exert the dominant control over the resistivity distribution of the landfill the most important potential information that can be recovered is therefore an indication of the waste piles hydraulics second it was neither possible to estimate the amount of recoverable soils nor to correlate the type of waste with the resistivity models however discrete anomalies were identified and if specific materials are searched for the resistivity models indicate possible places to search

environmental characterization of burnt coal gangue banks at yangquan shanxi province china the environmental characteristics of coal gangue dumps in yangquan shanxi province china were investigated the amounts of coal gangue are very high in this coal region given the large coal production as a result widespread spontaneous coal gangue combustion gives rise to serious environmental problems coal gangue including bulk gangue and specific lithologies such as coal kaolinite rich material sandstone carbonate minerals and sulfide mineralizations fired coal gangue and condensate products from gas vents were fully characterized with respect to mineralogy chemistry and leaching potential the mineral paragenesis of the fired coal gangue cristobalite mullite hematite trydimite cordierite showed that the combustion temperature could reach 1200 c this was also corroborated by laboratory calcination tests during this combustion some elements such as c cl f s n as cd hg pb sn ge and se are emitted into the atmosphere however condensation processes accounted for the partial trapping of gaseous emissions of as s n hg and se thus condensate mineralizations of elemental sulfur and ammonium salts enriched in se as and other trace elements are frequent in the gas vents the leaching potential of trace elements in the fresh coal gangue was relatively low but the leaching of weathered coal gangue and the gas vents condensates could give rise to environmental problems as these materials produce acidic leachates and yield relatively high leachable levels of a number of elements

control of regional structural styles and faulting on northeast mexico spring distribution groundwater dependent spring fed ecosystems of the cuatrocienegas basin coahuila mexico host 70 endemic species these desert springs occur primarily aligned along the base of an anticline that bisects the cuatrocienegas basin but the hydrogeologic controls of the springs are poorly understood the hypothesis that spring locations are controlled by subsurface geology such as buried anticlines or faulting versus stratigraphic controls is tested by evaluating 1 regional structural styles 2 fracture models of analogous structures 3 hydrogeologic data and 4 geophysical surveys jurassic and cretaceous siliciclastic and carbonate rocks deposited on the coahuila block west of the cuatrocienegas basin have dips 10 and lack faults because of a structurally rigid granodiorite basement to the east of the coahuila block and around the cuatrocienegas basin the coahuila folded belt has anticlines associated with basement involved faults 10 25 backlimb dips and forelimb dips up to vertical or slightly overturned springs in the western sub basin that represent 85 of total basin discharge are located on zones of highest anticipated fracture density predicted by fracture models of analogous anticlines spring waters reveal elevated temperature 32 35 c and low tritium 1 tritium unit gravimetry and time domain electromagnetic surveys correspond with a best fit cuatrocienegas basin hydrogeologic model of fractures associated with reverse faulting controlling spring locations in the western cuatrocienegas basin springs in the eastern sub basin are located where ephemeral streams have eroded through confining beds along the base of alluvial fans and lack faulting regional variations in structural style are an important control on the location of springs in the cuatrocienegas basin

coal mining impacts on water environs around the barapukuria coal mining area dinajpur bangladesh the present research makes an effort towards awareness of the impact of underground coal mining on water environment around the barapukuria coal mining area dinajpur by direct field investigation questionnaire survey and laboratory analysis for this research the three foremost errands have been mulled over which are the water level data analysis for 10 years from 2001 to 2011 ground water major parametric analysis and the questionnaire survey on the availability of ground water before and after coal mining operation the results of field and laboratory analysis show that the characteristics and concentrations of all the major physical and chemical parameters such as ph ec temperature hco3 no3 so4 2 cl na k mg2 ca2 and fe total are still tolerable for all purposes and also within the standard limit on the other hand the questionnaire survey and water level data analysis confirm almost similar results regarding the depletion of water level the water level has depleted more than 5 m from 2001 to 2011 therefore currently the availability of ground water is normal in the rainy and winter seasons but is slight problematic in the dry season where ground water was available at all times prior to coal mining in the area from these scenarios it is comprehensible that the ground water level moves downwards than earlier because of the excess pumping of water from the mine area besides the natural recharge condition is not enough and somewhere breaks off while some of the mines out areas are subsided consequently the upper part of the water bearing formations aquifer loses its porous and permeable properties resulting water recharging problem which is directly responsible for depleting the ground water level over the area moreover the water levels will also decline relative to the location depth recharge and discharge conditions of the mine both aerially and vertically while there is a typical relationship between the depth of mining and static water level which is water levels will decline more as the mine goes deeper therefore taking into account the current ground water condition and the depth of barapukuria coal mine this research implied that the water level will deplete more in day coming and the water crisis will be more for future thus this research recommends a sustainable guideline for long term planning and also suggests that regular monitoring with time to time more detail qualitative and quantitative assessments of water bodies in the area

remote sensing of hydrocarbon layers by seabed logging sbl results from a cruise offshore angola detecting and assessing hydrocarbon reservoirs without the need to drill test wells is of major importance to the petroleum industry seismic methods have traditionally been used in this context but the results can be ambiguous another approach is to use electromagnetic sounding methods that exploit the resistivity differences between a reservoir containing highly resistive hydrocarbons and one saturated with conductive saline fluids modeling presented by eidesmo et al 2002 demonstrates that by using seabed logging sbl a special application of frequency domain controlled source electromagnetic csem sounding the existence or otherwise of hydrocarbon bearing layers can be determined and their lateral extent and boundaries can be quantified such information provides valuable complementary constraints on reservoir geometry and characteristics obtained by seismic surveying

insight of the environmental awareness on waste rock disposal at heidong quarry dated 1000 years ago in se china similar to coal or metal ore mining the stone quarrying industry needs to achieve reasonable waste disposal to relieve the possible damage of waste to the environment it is believed that not just the modern quarries but also the ancient ones are required to deal with the waste disposal issue a large underground stone quarry dating back to the sui dynasty is located at zhejiang province southeast china the quarry named heidong quarry by locals consists of 21 individual caverns and occupies an area of 27 500 m2 it was observed that about 170 000 m3 of waste rocks are stacked in piles on the floor of almost all the caverns this paper investigated the geometry of the waste rocks including dimension and volume as well as inquired into the distinctive quarrying technique digging holes for quarrying stone slab employed in the quarry the rock mass characteristics in the quarry are surveyed and the excellent rock mass quality is verified using engineering geological and laboratory testing methods possible motives for stacking the waste rocks inside the quarry were analyzed taking account of the social system and economy in that time it is concluded that the ancient quarrymen chose to stack the waste rocks in quarry for eliminating farmland occupation by waste rocks it is clarified that the waste disposal method adopted by the ancients actually reflects their simple idea of minimizing human introduced destruction on the environment when the concept of environment protection was not even proposed

controlled electromagnetic sources for measuring electrical conductivity beneath the oceans 1 forward problem and model study exact closed form expressions for the electromagnetic induction fields produced by vertical and horizontal current sources in the conducting ocean overlying a one dimensional earth are derived from the maxwell equations numerical methods for the evaluation of the solutions are given including correction for the finite size of real sources simple models of the electrical conductivity structure of the ocean crust and lithosphere are deduced from geologic petrologic and laboratory data and their electromagnetic response is modeled horizontal electric dipole sources produce much larger field amplitudes than their vertical counterparts for a given frequency and range and the horizontal electric field offers superior received signal performance reflections of electromagnetic waves from the sea surface and thermocline must be considered for low enough frequencies or long ranges estimates of the ambient noise level from natural electromagnetic sources in the frequency range 0 01 10 hz are presented the ability of controlled sources to determine features of the conductivity of the ocean crust and upper mantle especially low conductivity zones is demonstrated if the mantle conductivity is low enough horizontal ranges of 50 km and conductivity estimates to over 20 km depth can be achieved

testing the limits of aem bathymetry with a floating tem system a floating transient electromagnetic tem system sea ring simulating a low altitude helicopter airborne electromagnetic aem system was constructed to test the accuracy of the aem method for measuring water depth and estimating sediment thickness in shallow coastal waters a square transmitter loop 10 10 m plus concentric inner and outer receiver loops was strung from masts supported by the circular sea ring base data were stacked over periods from 1 to approximately 60 s and with loop heights ranging between approximately 5 5 and 12 m above sea level the towed sea ring provides a stable platform at a known fixed altitude in calm waters we have undertaken modeling to investigate the effect of vertical and horizontal displacements of the loops and to compare circular and square loopgeometries in proximity to the sea surface with relatively long stacking times as long as approximately 60 s the uncertainty in altitude can be reduced to very low levels the sea ring has been deployed near

an investigation of aspects of mine waste from a kyanite mine central virginia usa kyanite mining corporation located in dillwyn virginia has been in operation for over 50 years and their local operation is the largest kyanite mine in the world as part of the processing at this location a magnetic separate is generated and a minimum estimation of 3 57 million tons of waste has accumulated currently no use for the magnetic separate has been identified we investigated eight representative samples of the magnetic mine waste which varied in color from a dark tan to black to determine if the waste could be recycled as an ore or could be used as an environmental media mineralogical investigations indicate the composition of the magnetic mine waste is dominated by magnetite kyanite lesser amounts of hematite and charcoal magnetite occurs as fine grained crystals and as inclusions in kyanite hematite occurs largely as botryoidal textures as discrete grains and as coatings on kyanite grains fe oxide spheres ranging in diameter from approximately 5 100 m are common and may compose up to 10 in some samples titanium dioxide was rarely observed as coatings on silicate mineral grains energy dispersive spectroscopy analysis on magnetite crystals indicates they have end member compositions bulk property investigations indicate that grain size distributions of samples are primarily unimodal with 20 40 of material being between 0 600 and 0 250 mm hydraulic conductivity values of samples investigated vary between 0 0036 and 0 0077 cm s and are broadly consistent with those expected of sands with similar grain size distributions in addition to the magnetic waste stream a light blue water soluble amorphous cu sulfate occurs as a coating on surfaces of boulders the coating is composed of rounded interlocking particles 5 60 m in diameter this material is of some environmental concern for freshwater invertebrates but can be managed using sorption media hyperspectral data were gathered of the magnetic separate kyanite ore samples and the light blue cu sulfate the signatures of the kyanite ore the blue mineral coating and a mixture of the two provide spectral fingerprints that an imaging spectrometer could exploit for rapid detection and subsequent environmental monitoring

geo environmental implications of military mining in flanders belgium 1914 1918 military mining is an ancient procedure that has often been used in the reduction of fortresses during siege warfare during the first world war 1914 1918 the western front that crossed western europe was effectively a linear fortress military mining was employed by all protagonists and involved the construction of dugouts underground shelters for housing men as well as the construction of subways for movement of men and materiel and mined tunnels for offensive action all these excavations connected with trenches open ditches up to 2 m deep as the armies left the field of battle at the end of the war trenches were most often filled in upon the return to agriculture but tunnels and dugouts often with small entrances were most often simply blocked off leaving open subterranean voids this is a particular problem in flanders where tunnels and dugouts were cut through a range of weak sediments usually supported by timber advancing age and changes in depth to reach water saturated ground are some of the features that have led to incidences of structural damage as a result of subsidence four case studies in flanders demonstrate the need for detailed surveys and hazard mapping in the region rich archives existing in europe and elsewhere demonstrate that the construction of historical engineering maps as an aid to planning is feasible

3d behaviour of contamination in landfill sites using 2d resistivity ip imaging case studies in portugal aiming at defining a valid spatial contamination model resistivity and induced polarization ip measurements were used to investigate contamination plumes in the vicinity of two municipal landfills ovar and ilhavo previous geophysical surveys and underground water samples confirmed the contamination however 2d resistivity ip surveys enabled in obtaining a more accurate spatial model the ovar survey consisted of two profiles with nine wenner soundings each the ilhavo survey was carried out along two individual lines using a wenner standard pseudo section in both situations negative ip values were found associated with positive ip values which can be explained mainly by 2d or 3d geometric effects caused by the presence of the conductive plumes the data were modelled using a 2d inversion program res2dinv and the resulting resistivity and chargeability distributions were displayed as pseudo sections the resistivity and chargeability pseudo sections define the contamination plumes and the sedimentary structure these case studies illustrate the advantages of 2d resistivity ip surveys for the mapping of shape and dimension of contamination associated with landfills

gravity inversion of basement relief and estimation of density contrast variation with depth we present a method to estimate the basement relief as well as the density contrast at the surface and the hyperbolic decaying factor of the density contrast with depth assuming that the gravity anomaly and the depth to the basement at a few points are known in both cases the interpretation model is a set of vertical rectangular 2d prisms whose thicknesses are parameters to be estimated and that represent the depth to the interface separating sediments and basement the solutions to both problems are stable because of the incorporation of additional prior information about the smoothness of the estimated relief and the depth to the basement at a few locations presumably provided by boreholes the method was tested with synthetic gravity anomalies produced by simulated sedimentary basins with smooth relief providing not only well resolved estimated relief but also good estimates for the density contrasts at the surface and for the decaying factors of the density contrast with depth the method was ap

dating of mining induced subsidence based on a combination of dendrogeomorphic methods and in situ monitoring abstract mining induced subsidence is a worldwide environmental problem that leads to damage to infrastructure and property thus knowledge of its past recent development is critically needed during land use planning moreover the temporal occurrence of subsidence is greatly variable with tendencies for gradual to abrupt movements subsidence rates can currently be achieved via radar interferometry but these data usually cover short time periods and are less accurate in forested areas in such cases dendrogeomorphic dating can provide chronologies of past subsidence activity in addition comparisons of tree ring based data with in situ monitoring may answer the sensitivity and reliability of dating methods in these specific conditions of continuous ground movement geomorphic mapping and dendrogeomorphic dating were performed at two forested landslide sites affected by coal mining subsidence in the upper silesian basin czech republic and the resulting chronology from one site was compared with levelling campaigns occurring from 1998 to 2015 based on 284 increment cores from 71 trees we were able to identify 7 subsidence events at the site dominated by a pioneering forest and 19 subsidence events at the site overgrown by a mature forest with the most frequent responses occurring from 1956 to 1971 and 2005 2011 the occurrence of multiple compression wood growth intervals some occurring in different directions of tree stems more than 30 of sampled trees indicated complex deformations presented by the flow like mechanism of waterlogged surfaces ongoing subsidence spreading and fragmentation of larger blocks and grabens a comparison of tree ring based chronology with in situ monitoring revealed good synchronicity with the periods of increased subsidence rates between 1 and 3 m year 1 thus indicating the high relevance of dendrogeomorphic methods for the determination of the most intense periods of ground subsidence our results show the first comparison of dendrogeomorphic methods with in situ monitoring of human induced subsidence areas and provide an alternative option for reconstructing decadal to centennial development of the affected areas

geochemistry of trace elements in chinese coals a review of abundances genetic types impacts on human health and industrial utilization abstract china will continue to be one of the largest coal producers and users in the world the high volume of coal use in china has focused attention on the amounts of toxic trace elements released from coal combustions and also the valuable trace elements extracted or potentially utilized from coal ash compared to world coals chinese coals have normal background values for most trace elements with the exception of higher li 31 8 g g zr 89 5 g g nb 9 44 g g ta 0 62 g g hf 3 71 g g th 5 84 g g and rare earth elements la lu y 136 g g this is not only due to the higher ash yields of chinese coals but also to alkali volcanic ashes found in some southwestern coals the background values of toxic elements of hg 0 163 g g as 3 79 g g and f 130 g g in chinese coals are comparable to coals from most other countries the genetic types for trace element enrichment of chinese coals include source rock controlled marine environment controlled hydrothermal fluid controlled including magmatic low temperature hydrothermal fluid and submarine exhalation controlled subtypes groundwater controlled and volcanic ash controlled the background values of trace elements were dominated by sediment source regions low temperature hydrothermal fluid was one of the major factors for the local enrichment of trace elements in southwestern china serious human health problems caused by indoor combustion of coal in china include endemic fluorosis arsenosis selenosis and lung cancer endemic fluorosis mainly occurring in western guizhou was mostly attributed to the high fluorine in clay that was used as a briquette binder for fine coals in addition to a small quantity of fluorine from coal fluorine in the coal from endemic fluorosis areas of western guizhou is within the usual range found in china and the world endemic arsenosis in southwestern guizhou is attributed to indoor combustion of high as coal endemic selenosis in enshi of hubei was due to high se in carbonaceous siliceous rocks and carbonaceous shales fine particles of quartz released into air during coal combustion are hypothesized as a possible cause for the lung cancer epidemic in xuanwei yunnan china valuable elements including ge ga u ree rare earth element nb zr and re are concentrated to levels comparable to conventional economic deposits in several coals or coal bearing strata in china the ge deposits at lincang yunnan province and wulantuga inner mongolia have been exploited and industrially utilized the enrichment of ge in the two deposits was caused by hydrothermal fluids associated with adjacent granitoids the ga al ore deposit in the jungar coalfield inner mongolia was derived from the neighboring weathered and oxidized bauxite of the benxi formation pennsylvanian the nb ta zr hf ree ga deposits in the late permian coal bearing strata of eastern yunnan and chongqing of southwestern china were attributed to ashes of the alkali volcanic eruptions

mining induced ground deformation in tectonic stress metal mines a case study abstract in situ monitoring data of ground deformation in the western area of chenchao iron mine were collected over eight years results were analysed to conduct a preliminary investigation into the ground movement induced by underground mining 1 in the northeastern area the ratios of horizontal to vertical displacement increase gradually and the horizontal displacement may be as much as an order of magnitude larger than the vertical displacement at a large distance which induces regional horizontal movement curves of the ratio of horizontal to vertical displacement with respect to time can be categorised as fluctuation fallback convergence and increase types 2 in the mine road stack site and southern area around the high voltage tower ground deformation can be divided into two stages stable deformation and rapid deformation while in the southeastern area of the transport tunnel service shaft and road tunnel it can be divided into three stages stable deformation rapid deformation and subsequent stable deformation three categories are found in the time displacement curves folding s and linear types 3 the ground deformation of the footwall underwent a significant change in january 2010 because the large horizontal tectonic stress in the mine was released at that time surrounding rock masses were subjected to toppling deformation along the major structural plane in the northeastern area while tensile deformation occurred perpendicular to the major structural plane in the northern area

monitoring study of the mine pond reclamation of mina concepcion iberian pyrite belt spain mining of massive cu pb and zn sulphide bodies in the iberian pyrite belt sw spain has generated a great number of abandoned waste deposits such as mine ponds these represent large accumulations of reactive minerals and subsequently emission sources of trace elements and formation of acid drainage even if they have been restored monitoring studies are required to evaluate the corrective effects and how they may change over time this work presents the results of a monitoring study carried out at mine concepcion mine pond based on mineralogical xrd geochemical inaa x ray fluorescence icp ms and geophysical electrical resistivity tomography techniques in it a series of relevant parameters have been well delimited such as the infilling thickness and its variation and the position geometry and absence of water leakages through the base of the mine pond additionally the existence of an internal remnant flow of acid waters that tends to come out through the pond dyke has been identified chemistry of these waters indicates that oxidation processes affecting the mina concepcion mine tailings are generating acid drainage waters which could potentially release substantial amounts of trace elements to the river odiel thus giving that not complete sealing is accomplished by the restoration capping and rainfall water infiltrates into the pond materials at least the sealing of the dyke through which leakages occur should be revised

evidence of hierarchy in the complex fractured system of geropotamos crete greece as extracted from transient electromagnetic responses the essential goals of this paper are to test the transient electromagnetic tem response in a fractured geological complex medium and to better understand the physics introduced by associating a roughness parameter to the geological formation an anomalous fractional diffusion approach is incorporated to describe the electromagnetic induction in rough multi scaled geological structures the multi scaling characteristics of geropotamos basin in crete are revealed through the analysis of transient step off response of an em loop antenna the semi empirical parameters derived from late time tem measurements are correlated with the multi scale heterogeneities of the medium certain interesting properties of the late time slope and the power law of near surface resistivity distribution as extracted from tem inversion for different depth are presented the analysis of the parameter which scales the induced voltage in the loop in the late stage of the electromagnetic response leads to a different view of the em geophysical data interpretation we show that it is strongly correlated with areas of high fracture density within the geological formations of the geropotamos area for that reason it is proposed as a local multi scaling empirical index the results of this paper suggest that anomalous diffusion could be a viable physical mechanism for the fractal transport of charge carriers explaining observed late time tem responses across a variety of natural geological settings

concept of effective density key to gravity depth determinations for sedimentary basins the gravity anomaly observed over a layered sedimentary basin is close to that calculated over a basin with the same configuration and depth but filled by homogeneous sediments with density equal to the effective weighted average density of the real layered basin therefore it is possible to calculate the effective density contrast of a basin from the residual gravity anomaly over it if the depth of the basin is known at least at one point assuming a mathematical function for density depth dependence an expression for the gravity depth dependence using the infinite slab bouguer formula can be developed this expression makes it possible to calculate the depth of a basin or an isopach map from gravity data an exponential function and a new hyperbolic density depth function and their gravity depth functions are analyzed and implemented for determining the depths of basins from gravity data for the san jacinto graben california and the tucson basin southern arizona the hyperbolic functions are m

trace element characteristics of different pyrite types in mesoarchaean to palaeoproterozoic placer deposits a comparative in situ la icp ms trace element study on pyrite from three different variably auriferous archaean to palaeoproterozoic palaeoplacer deposits in the ouro fino syncline quadrilatero ferrifero brazil the elliot lake area north of lake huron se canada and several deposits within the witwatersrand basin south africa revealed systematic differences between morphologically different pyrite types and between the various palaeoplacer deposits especially the ni and au concentrations as well as co ni and mo ni ratios were found to be systematically different in detrital compact detrital porous and post sedimentary hydrothermal pyrite grains from different source areas high co ni ratios and low au concentrations are typical of post sedimentary pyrite which is hydrothermal in origin in contrast relatively low co ni ratios and high au contents characterise detrital porous banded and concentric pyrite grains au 1 ppm which are syn sedimentary in origin in the elliot lake area and the witwatersrand basin detrital compact rounded pyrite is characterised by high co ni ratios which is in agreement with derivation from a hydrothermal source low au concentrations in this pyrite type support the contention of the gold and the pyrite in these deposits coming from different source rocks in contrast derivation from an originally diagenetic pyrite is suggested for the detrital compact pyrite in the ouro fino syncline because of low to intermediate co ni ratios high au contents may indicate a genetic relationship between pyrite and gold there systematic differences exist between the three areas with respect to au ni co mo and cu distributions in detrital pyrite which reflects differences in the provenance a predominantly mafic ultramafic source is indicated for the ouro fino a felsic source for the elliot lake and a mixed felsic mafic provenance for the witwatersrand pyrite populations independently of pyrite type the higher au endowment of the studied witwatersrand and ouro fino conglomerates are also reflected by an overall higher au concentration in the respective pyrite grains compared to the relatively au poor samples from elliot lake in general a strong positive correlation between au and pb levels in the various pyrite grains is noted analogous to pb which is well known for not being easily accommodated in the pyrite crystal lattice but occurring as discrete pbs phases au is considered to be present mainly in the form of discrete au phases in minute pores and interstices of the pyrite grains rather than within the pyrite lattice

human topographic signatures and derived geomorphic processes across landscapes abstract the earth s surface morphology in an abiotic context is a consequence of major forcings such as tectonic uplift erosion sediment transport and climate recently however it has become essential for the geomorphological community to also take into account biota as a geomorphological agent that has a role in shaping the landscape even if at a different scale and magnitude from that of geology although the modern literature is flourishing on the impacts of vegetation on geomorphic processes the study of anthropogenic pressures on geomorphology is still in its early stages topography emerges as a result of natural driving forces but some human activities such as mining agricultural practices and the construction of road networks directly or indirectly move large quantities of soil which leave clear topographic signatures embedded on the earth s morphology these signatures can cause drastic changes to the geomorphological organization of the landscape with direct consequences on earth surface processes this review provides an overview of the recent literature on the role of humans as a geological agent in shaping the morphology of the landscape we explore different contexts that are significantly characterized by anthropogenic topographic signatures landscapes affected by mining activities road networks and agricultural practices we underline the main characteristics of those landscapes and the implications of human impacts on earth surface processes the final section considers future challenges wherein we explore recent novelties and trials in the concept of anthropogenic geomorphology herein we focus on the role of high resolution topographic and remote sensing technologies the reconstruction or identification of artificial or anthropogenic topographies provides a mechanism for quantifying anthropogenic changes to landscape systems this study may allow an improved understanding and targeted mitigation of the processes driving geomorphic changes during anthropogenic development and help guide future research directions for development based watershed studies human society is deeply affecting the environment with consequences on the landscape therefore establishing improved management measures that consider the earth s rapidly changing systems is fundamental

detecting the footprint of a longwall mine panel claimed to infringe on a permit boundary at the soma darkale coalfield manisa turkey using surface fractures and microgravity measurements a coal mine panel claimed to infringe on a permit boundary or to create an hazard after subsidence has been the subject of lawsuits we study at the soma darkale coalfield manisa turkey the footprint of a lignite coal mine panel at a depth of about 150 200 m by mapping all of the surface fractures we could observe and by developing a post subsidence density model that we verified through gravity measurements with positive bouguer anomaly with the analysis of the fracture map and the gravity data we were able to identify the footprint of a mine panel from the effect of the anomalous mass due to denser overburden material filling up the space after the extraction of less dense lignite whereas using empirical methods like the so called limit line approach to evaluate the extent of the area where mining can have subsidence induced surface fracturing one could not recognize for certain infringement of permit boundaries the orientations of the fractures we mapped at the ground surface the bouguer gravity map and a test borehole indicated the presence and dimensions of a coal panel in dispute the presented approach based on gravity method and fracture observations may be an example to help settle conflicts related to the position of the longwall mine panel

mapping the magnetic susceptibility and electric conductivity of marine surficial sediments by benthic em profiling distribution accumulation and diagenesis of surficial sediments in coastal and continental shelf systems follow complex chains of localized processes and form deposits of great spatial variability given the environmental and economic relevance of ocean margins there is growing need for innovative geophysical exploration methods to characterize seafloor sediments by more than acoustic properties a newly conceptualized benthic profiling and data processing approach based on controlled source electromagnetic csem imaging permits to coevally quantify the magnetic susceptibility and the electric conductivity of shallow marine deposits the two physical properties differ fundamentally insofar as magnetic susceptibility mostly assesses solid particle characteristics such as terrigenous or iron mineral content redox state and contamination level while electric conductivity primarily relates to the fluid filled pore space and detects salinity porosity and grain size variations we develop and validate a layered half space inversion algorithm for submarine multifrequency csem with concentric sensor configuration guided by results of modeling we modified a commercial land csem sensor for submarine application which was mounted into a nonconductive and nonmagnetic bottom towed sled this benthic em profiler neridis ii achieves 25 soundings second at 3 4 knots over continuous profiles of up to a hundred kilometers magnetic susceptibility is determined from the 75 hz in phase response 90 signal originates from the top 50 cm while electric conductivity is derived from the 5 khz out of phase quadrature component 90 signal from the top 92 cm exemplary survey data from the north west iberian margin underline the excellent sensitivity functionality and robustness of the system in littoral 0 50 m and neritic 50 300 m environments susceptibility versus porosity crossplots successfully identify known lithofacies units and their transitions all presently available data indicate an eminent potential of csem profiling for assessing the complex distribution of shallow marine surficial sediments and for revealing climatic hydrodynamic diagenetic and anthropogenic factors governing their formation

the impact of disposal and treatment of coal mining wastes on environment and farmland in china coal mining wastes have traditionally been dumped in cone shaped heaps that have the potential to pollute air soil and water environments and landscapes through dust generation leachate production self ignition and as a consequence of an absence of vegetation cover since 1980s the disposal technique for coal mining wastes has been changing and in many instances the wastes are now transported directly to subsided land as a fill to enable the reuse of that land thus today both coal mining waste dumps from the past and filled subsided lands are in existence however the comparative impacts of these different disposal techniques on the environment and farmland productivity have not been studied in detail using dongtan dt nantun nt and xinglongzhuang xlz coal mines as examples the components of coal mining wastes and their potential pollution contribution to soil surface water and ground water are tested in situ the results show that contaminants are released after self ignition and weathering of coal mining wastes but they are not above the allowable environmental standards however despite these findings more and closer attention needs to be paid to the mobility transportation and accumulation of these contaminants in the environment over time

mercury binding forms in coals and their geological provenances in coals of different types mercury hg is an element of environmental and geological significance quantification of different hg binding forms is crucial to understand geological hg provenances and associated geochemical processes during coal formation in this study seven coal samples were selected according to coal rank i e middle volatile bituminous c 3 low volatile bituminous c 2 anthracite c 1 chemical anomalies high s coal ibc 105 high cl coal c22650 and sampling environment fresh coal lh weathered coal lhw to determine their hg binding forms using well established sequential extraction procedures coupled with sink float experiment in the thermally metamorphosed samples c 1 and c 2 a comparative enrichment of total hg relative to c 3 is observed silicate and organic bound hg are the dominant hg binding forms in c 1 suggesting possible hg sources from magma silicate and secondary hg enrichment by adsorption sulfide and organic bound hg are the most abundant hg binding forms in ibc 105 whereas only organic bound hg dominates in cc22650 weathering processes are suggested to transform the abundant sulfide bound hg in lh to silicate and organic bound hg in its weathering product lhw

investigating the characteristics of mine water in a subsea mine using groundwater geochemistry and stable isotopes investigation were conducted in the xinli subsea mine from 2006 to 2011 which is the largest subsea mine in china and threatened by the overlying quaternary aquifer and seawater hydrochemical and stable isotopic 2h and 18o analyses were used to study the relationships between various waters hydrochemical results indicated that the seepage water in the mine tunnels had higher ec tds and concentrations of most elements than the seawater and saline groundwater water analyses indicated the mine discharge was a mixture of the seawater brine and atmospheric precipitation the proportions of the three different sources were calculated based on hydrochemical and isotopic analyses the seepage water were more isotopically enriched than the seawater but less than the brine in addition the isotope mixing calculation indicated that the average proportions of mine water from seawater brine and atmospheric precipitation were about 38 5 46 and 15 5 respectively for the entire mine in 2006 however the concentrations of these analyses decreased and the proportion of the seawater increased 21 1 after 5 years of exploitation in 2011 these changes demonstrated that the surrounding rock mass underwent a certain extent of deformation and failure because of the mining disturbance which enhanced the permeability of the surrounding rock mass

a time domain electromagnetic survey of the tag hydrothermal mound a conductivity survey of the tag mound was made using innovative transient electric dipole dipole instrumentation the receiver was deployed on the sulfide mound 30 m south of the central black smoker while the submersible alvin carried the transmitter on a survey path around the receiver at a radius of approximately 70 m conductivity measurements of the seafloor between the transmitter and receiver were made at 5 minute intervals the survey lasted 4 hours measurements made at 12 sites are initially interpreted in terms of an apparent conductivity of a uniform seafloor a more complex model in which the seafloor has two layers is then used apparent conductivities range from 1 4 to 15 9 s m generally higher than that of seawater the results suggest possible focusing of hydrothermal convection in the northern quadrant of the mound adjacent zones of anhydrite accumulation and fluid convection in the north eastern quadrant heterogeneity and layering in the kremlin zone and unexpected spatial variability in the western quadrant the data from several sites show evidence of distortion attributed to 3 d anomalies

gravity data as a tool for detecting faults in depth enhancement of subtle almada s basement faults brazil we demonstrate the potential of gravity data to detect and to locate in depth subtle normal faults in the basement relief of a sedimentary basin this demonstration is accomplished by inverting the gravity data with the constraint that the estimated basement relief presents local abrupt faults and is smooth elsewhere we inverted the gravity data from the onshore almada basin in northeastern brazil and we mapped several normal faults whose locations and plane geometries were already known from seismic imaging the inversion methoddelineatedwellboththediscontinuitieswithsmallor largeslipsandasequenceofstepfaults usingsyntheticdata weperformedasystematicsearchofnormalfaultslipsversus fault displacement depths to map the fault detectable region inthisspace thismappinghelpstoassesstheabilityofgravityinversiontodetectnormalfaults mappingshowsthatnormalfaultswithsmall0 5 km mediumabout1 km and large about 2 km vertical slips can be detected if the maximummidpointdepthsofthefaultplanesaresmallerthan1 8 3 8 and6 8 km respectively

marine downhole to seafloor dipole dipole electromagnetic methods and the resolution of resistive targets most active marine electromagnetic surveys use an array of transmitting and receiving electric dipoles located on the sea floor there are many reports of successful detections of buried resistors with these arrays nevertheless the concept has a significant drawback large offsets between the transmitter and receiver with respect to the target depth are needed a logical alternative is the use of a vertical electric dipole transmitter in a borehole deeper than the target combined with receivers located at the seafloor because current must pass through the target even data recorded at short offsets with respect to target depth should be sensitive to the target we derived the equations for the electric and magnetic field components produced by the vertical electric dipole in a 1d layered medium the equations are used to model the fields for resistive layers an eigenparameter analysisis applied to the different field components and the resolution is compared with the standard seafloor inline array

mining subsidence and its effect on the environment some differing examples the impact of mining subsidence on the environment can occasionally be very catastrophic destroying property and even leading to the loss of life usually however such subsidence gives rise to varying degrees of structural damage that can range from slight to very severe different types of mineral deposits have been mined in different ways and this determines the nature of the associated subsidence some mining methods result in contemporaneous subsidence whereas with others subsidence may occur long after the mine workings have been abandoned in the latter instance it is more or less impossible to predict the effects or timing of subsidence a number of different mineral deposits have been chosen to illustrate the different types of associated subsidence that result and the problems that arise the examples provided are gold mining in the johannesburg area bord and pillar mining of coal in the witbank coalfield south africa longwall mining of coal in the ruhr district mining of chalk and limestone in suffolk and the west midlands respectively and solution mining of salt in cheshire these mineral deposits have often been worked for more than 100 years and therefore a major problem results from abandoned mines especially those at shallow depth the presence of which is unrecorded abandoned mines at shallow depth can represent a serious problem in areas that are being developed or redeveloped abstraction of natural brine has given rise to subsidence with its own particular problems and cannot be predicted although such abstraction is now inconsequential in cheshire dereliction associated with past subsidence still remains

engineering geology ground surface movement and fissures induced by underground mining in the jinchuan nickel mine the jinchuan nickel mine is the largest underground mine with cut and fill mining in china in 1999 there appeared evident ground surface movement and many ground fissures in jinchuan no 2 mine following an introduction to the engineering geology and mechanical properties of the rock mass in the jinchuan mine areas this paper reveals the features of the measured in situ stresses and puts emphasis on an analysis of the mechanism of surface movement and ground fissures induced by the underground mining with backfill it is indicated that both the fault structures and the alteration contact zones are well developed as the dominant engineering geological characteristics in the jinchuan mine areas the stress redistribution in surrounding rocks resulting from the mining the low stiffness of the filling body the existence of the void space and the influence of on going mining activities is the main reason for the occurrence of surface movement and ground fissures

heavy metal partitioning in river sediments severely polluted by acid mine drainage in the iberian pyrite belt this study provides a geochemical partitioning pattern of fe mn and potentially toxic trace elements as cd cr cu ni pb zn in sediments historically contaminated with acid mine drainage as determined by using a 4 step sequential extraction scheme at the upperstream the sediments occur as ochreous precipitates consisting of amorphous or poorly crystalline oxy hydroxides of fe and locally jarosite whereas the estuarine sediments are composed mainly of detrital quartz illite kaolinite feldspars carbonates and heavy minerals with minor authigenic phases gypsum vivianite halite pyrite the sediments are severely contaminated with as cd cu pb and zn especially in the vicinity of the mining pollution sources and some sites of the estuary where the metal concentrations are several orders of magnitude above background levels although a significant proportion of zn cd and cu is present in a readily soluble form the majority of heavy metals are bonded to reducible phases suggesting that fe oxy hydroxides have a dominant role in the metal accumulation in the estuary the sediments are potentially less reactive than in the riverine environment because relevant concentrations of heavy metals are immobilised in the crystalline structure of minerals

gravity inversion of basement relief using approximate equality constraints on depths we present a gravity interpretation method for estimating the relief of an arbitrary interface separating two homogeneous media the upper medium is discretized into rectangular juxtaposed prisms whose thicknesses represent the depths to the interface and are the parameters to be estimated from the gravity anomaly the density contrast of each prism is assumed to be constant and known to stabilize the inversion we introduce two kinds of constraints on the depths the first one requires proximity between the observed and computed depths at isolated points such as those obtained from boreholes absolute equality constraint the second one requires that groups of depths approximately follow an established linear relationship among the depths relative equality constraint both kinds of constraints are imposed in the least squares sense we illustrate the method performance by applying it to a synthetic anomaly produced by a simulated basement relief consisting of four narrow and adjacent structural lows

mineralogical and geochemical investigation of clay rich mine tailings from a closed phosphate mine bartow florida usa clay rich mine tailings from phosphate mine operations in florida are a major environmental and economic problem options for reclamation and restoration for these tailings are very limited and are fundamentally restricted by poor physical properties such as low mechanical strength low hydraulic conductivity and heavy metal content the major control on these bulk physical properties is the mineralogy of the materials eight continuous push borings were obtained to investigate stratigraphy mineralogy aspects of geochemistry and bulk properties of a deposit of clay rich mine tailings from a phosphate mine near bartow florida that ceased operations in the early 1970s stratigraphy is dominated by laminated clay rich sediment with minor units of silt and sand an intact kaolinite liner occurs near the impoundment walls and the impoundment floor has approximately 4 m of relief moisture content varies from 4 35 to 57 40 wt and organic content varies from 0 41 to 9 53 wt bulk xrf investigation indicates that the p2o5 concentrations vary from approximately 4 to 21 wt a very strong correlation r2 0 92 between cao and p2o5 indicates that apatite is a major control on the phosphate the strong correlation r2 0 77 of al2o3 and tio2 suggests that the source materials for this deposit are comparatively uniform a number of heavy metal elements and trace elements occur cr v ni cu are interpreted to be in phosphate minerals largely apatite sr and pb are interpreted to be in both phyllosilicates and phosphate minerals two populations of apatite were observed in the clay sized fraction one that was fe and si bearing and another that was only si bearing fe bearing apatite had fe2o3 contents that varied from 0 38 to 5 32 wt and sio2 contents that varied from 0 90 to 3 32 wt the other apatite population had a wider range of sio2 contents that varied from 0 77 to 8 80 wt tem imaging shows that apatite grains are dominantly single crystals with lesser amounts of aggregates wavellite commonly occurs as individual or clusters of lath like crystals and the chemical composition differs from the pure aluminium phosphate end member with average concentrations of components being that of cao 1 57 wt fe2o3 1 98 wt sio2 5 94 wt in the clay sized phosphate minerals investigated no fluorine was found above detection limit approximately 0 15 wt nor was any uranium radium heavy metal or ree element detected the phyllosilicate mineralogy of the deposit is dominated by smectite montmorillonite with lesser amounts of nontronite palygorskite illite and kaolinite no systematic variation in the relative proportions of phyllosilicates was observed in the clay deposit energy dispersive spectroscopy eds analysis indicates that chemical compositions of phyllosilicates are somewhat typical but overall are enriched with respect to fe compared to theoretical end members the relative enrichment of fe is interpreted to be a primary sedimentary feature ca content in smectite minerals is high and may inhibit stabilization using lime or similar methods the high percentages of montmorillonite and palygorskite explain the high bulk water contents observed this investigation provides fundamentally new details regarding clay tailing deposits from closed phosphate mines in central florida which can be used in restoration and reclamation efforts

mineralogical and geochemical investigations of silicate rich mine waste from a kyanite mine in central virginia implications for mine waste recycling a kyanite mine in central virginia produces a silicate rich waste stream which accumulates at a rate of 450 000 600 000 tons per year an estimated 27 million tons of this waste stream has accumulated over the past 60 years grain size distribution varies between 1 000 and 0 053 mm and is commonly bimodal with modes typically being 0 425 and 0 250 mm and uniformity coefficients vary from 2 000 to 2 333 hydraulic conductivity values vary from 0 017 to 0 047 cm s mineralogy of the waste stream consists of quartz muscovite kyanite and hematite muscovite grains have distinct chemical compositions with significant na2o content 1 12 2 66 wt tio2 content 0 63 1 68 wt tio2 and fe content expressed as fe2o3 up to 1 37 wt major element compositions of samples were dominated by sio2 87 894 90 997 wt al2o3 6 759 7 741 wt fe2o3 1 136 1 283 wt and k2o 0 369 0 606 wt with other components being 1 000 wt elements of environmental concern v cr ni cu zn as ag sn sb ba hg tl and pb were detected however the concentrations of all elements except ni were below that of the kyanite quartzites in the region from which the waste is derived both major and trace element compositions indicate minimal variation in composition the waste stream has potential for recycling muscovite is suitable for recycling as a paint pigment or other industrial applications muscovite and hematite are commonly intergrown and are interpreted to be material where much of the elements of environmental concern are concentrated reprocessing of the waste stream to separate muscovite from other components may enable the waste stream to be used as constructed wetland media for virginia and nearby states recycling of this mine waste may have a positive impact on the local economy of buckingham county and aid in mitigation of wetland loss

refraction tomography over a buried waste disposal site determining the depth and geometry of a landfill s lower boundary is a difficult task potential field methods generally lack the necessary depth resolution and seismic reflection data are usually contaminated by source generated noise in the time range of interest 50 ms to address this problem we have developed a surface 2 d tomographic refraction scheme that is based on a fast finite difference eikonal solver and an inversion method that incorporates appropriate damping and smoothing constraints this new scheme has been applied to a first arrival traveltime data set collected across adjacent landfills in northern switzerland high quality seismic data were collected along five profiles that crossed the landfills and two that sampled undisturbed natural sediments seismic waves generated from multiple shots were recorded on large numbers of closely spaced receivers during quiet evening periods reliability of the resultant velocity tomograms was estimated on the basis of 1 ray diagrams 2 plot

a study on soil basic characteristics main microbial flora and typical metal fraction surrounding coal gangue dump in xiangtan hunan province south of china during the coal ore mining and utilization process coal and its associated minerals have been discharged as coal gangue upon interacting with the water air and microbial oxidation the harmful metals and sulfides in coal gangue will cause serious pollution in present work the basic chemical characteristics main microbial flora and typical metal speciation of the soil around coal gangue dump in liejiaqiao coal mine xiangtan mining area hunan province south of china were analyzed with several methods including xrf xrd microbial plate culture count and tessier s sequential extraction scheme correlation cluster and principal component analysis pca were used to estimate the possible main factors of coal gangue dump s effect on surrounding soil and their correlation with microbial flora research results showed that the soil surrounding the coal gangue dump had low ph and microbial abundance including bacteria fungi and actinomycete the soil samples contained high levels of metals especially for mn fe and cr tessier s sequential extraction results showed that fe mn and cr were mainly associated residual fraction risk assessment revealed that fe and cr had lower risk than mn to the surrounding environment based on pca and cluster analysis results the obtained ten samples can be divided into three groups among of them mobile fraction of metals microbial abundance could be the main factor reflecting the soil pollution around the coal gangue dump furthermore correlation analysis showed that the abundance of bacteria and actinomycete had significant relationship at 0 05 levels with mobility factor of fe and ph condition of the soil samples respectively

study of the hydrogeological characteristics and permeability of the xinli seabed gold mine in laizhou bay jiaodong peninsula china this paper presents a case study investigation into the hydrogeological characteristics and permeability of rock mass in a seabed mine following an introduction to the geology and hydrogeological conditions in the xinli mine area we reveal the features of the preferred structural planes dynamic characteristics of mine water seepage and the permeability of the fractured rock mass in the pit the permeability of the pit rock mass shows varied characteristics at different geotectonic locations because of the different degrees to which the structural planes developed the fractured rock mass generally shows low permeability and the main composition of water seepage is high salinity brine future large scale undersea mining may induce rock mass movement destroy water resistant layers and enhance water transmissibility and the probability of water gushing into the pit thus strengthening the quality of the filling mass protecting the stope roof and the water resistant layers as well as regular monitoring of water seepage discharge and identification of water sources are critical to work safety and the prevention of seawater gushing in the mine

trace element emissions from spontaneous combustion of gob piles in coal mines shanxi china the emissions of potentially hazardous trace elements from spontaneous combustion of gob piles from coal mining in shanxi province china have been studied more than ninety samples of solid waste from gob piles in shanxi were collected and the contents of twenty potentially hazardous trace elements be f v cr mn co ni cu zn as se mo cd sn sb hg tl pb th and u in these samples were determined trace element contents in solid waste samples showed wide ranges as compared with the upper continental crust the solid waste samples are significantly enriched in se 20x and tl 12x and are moderately enriched in f as mo sn sb hg th and u 2 5x the solid waste samples are depleted in v cr mn co ni cu and zn the solid waste samples are enriched in f v mn cr co ni cu zn sb th and u as compared with the shanxi coals most trace elements are higher in the clinker than in the unburnt solid waste except f sn and hg trace element abundances are related to the ash content and composition of the samples the content of f is negatively correlated with the ash content while pb is positively correlated with the ash the concentrations of as mn zn and cd are highly positively correlated with fe2o3 in the solid waste the as content increases with increasing sulfur content in the solid waste the trace element emissions are calculated for mass balance the emission factors of trace elements during the spontaneous combustion of the gobs are determined and the trace element concentrations in the flue gas from the spontaneous combustion of solid waste are calculated more than a half of f se hg and pb are released to the atmosphere during spontaneous combustion some trace element concentrations in flue gas are higher than the national emission standards thus gob piles from coal mining pose a serious environmental problem