Anomalous Sites Research Articles

English

An integrated geoelectrical study combining electrical resistivity tomography (ERT) and induced polarization (IP) have been used to delineate potential zones of Lead-Zinc mineralization in Umuobuna, Uburu, Ohaozara local government area, southeastern Nigeria. The wenner array configuration was used to acquire resistivity and induced polarization data sets along three traverses of approximate length of 1 km each and spacing of 5 to 25 m, using ABEM Terrameter SAS 1000. The profiles were inverted using RES2DINV software for 2D imaging to delineate possible zones of Pb-Zn mineralization and the geological structures at selected locations in the study area. The ERT surveys were carried out along the IP lines for comparison of anomalies across the profiles. The potential zones of Pb-Zn mineralization display contrasting values of resistivity and chargeability along the traverses. Resistivity values ranging from 7.53 to 7525 ?m and corresponding chargeability values of between -15.6 and 354 ms, respectively were encountered at some intervals along the traverses. These zones occur at width range 19.5 to 74.5 m and depths of between 0.9 and 15.5 m. Having a low to moderate resistivity and a corresponding high chargeability values at similar width range may be suggestive of Pb-Zn mineralization and test drilling is needed at the anomalous sites for confirmation. Key words: Pb-Zn, ERT, IP, resistivity, chargeability, mineralization.

Compositional measurement of gas emissions in the Eastern Carpathians (Romania) using the Multi-GAS instrument: Approach for in situ data gathering at non-volcanic areas

The Multi-GAS, a robust and low-cost instrument for real-time in-situ gas measurements, has previously been used mainly for compositional measurements of active volcanic plumes. Here we demonstrate novel use of a specially designed Multi-GAS instrument adapted to low temperature degassing areas. We performed compositional measurements in the Eastern Carpathians on dry and bubbling gas emissions using a sensor kit that allows measurement of CO2, CH4 and H2S (three major components of low-temperature hydrothermal/volcanic manifestations). Our results demonstrate good agreement between Multi-GAS measurements and independently obtained CO2 concentrations from gas chromatography. We also provide some novel H2S information for some anomalous sites, which we relate to possible alteration processes of sulphide minerals. The use of Multi-GAS in such environments could open new possibilities for data collection at non-volcanic areas and exploration of mineral resources. Moreover, it can also be a useful tool in exploration surveys to select the best sampling sites for more detailed laboratory measurements.

Hydrogeochemical Characteristics of Hot Springs and Their Short-Term Seismic Precursor Anomalies along the Xiaojiang Fault Zone, Southeast Tibet Plateau

Significant hydrogeochemical changes may occur prior- and post-earthquakes. The Xiaojiang fault zone (XJF), situated in a highly deformed area of the southeastern margin of the Tibetan Plateau, is one of the active seismic areas. In this study, major and trace elements, and hydrogen and oxygen isotopes of 28 sites in hot springs along the XJF were investigated from June 2015 to April 2019. The meteoric water acts as the primary water source of the hot spring in the XJF and recharged elevations ranged from 1.8 to 4.5 km. Most of the hot spring water in the study area was immature water and the water–rock reaction degree was weak. The temperature range was inferred from an equation based on the SiO2 concentration and chemical geothermal modeling: 24.3~96.0 °C. The circulation depth for the springs was estimated from 0.45 to 4.04 km. We speculated the meteoric water firstly infiltrated underground and became heated by heat sources, and later circulated to the earth’s surface along the fault and fracture and finally constituted hot spring recharge. Additionally, a continuous monitoring was conducted every three days in the Xundian hot spring since April 2019, and in Panxi and Qujiang hot springs since June 2019. There were short-term (4–35 d) seismic precursor anomalies of the hydrochemical compositions prior to the Xundian ML4.2, Dongchuan ML4.2, and Shuangbai ML5.1 earthquakes. The epicentral distance of anomalous sites ranged from 19.1 to 192.8 km. The anomalous amplitudes were all over 2 times the anomaly threshold. The concentrations of Na+, Cl−, and SO42− are sensitive to the increase of stress in the XJF. Modeling on hydrology cycles of hot springs can provide a plausible physicochemical basis to explain geochemical anomalies in water and the hydrogeochemical anomaly may be useful in future earthquake prediction research of the study area.

Application of the C-N fractal model, factor analysis and geochemical mineralization probability index (GMPI) for delineating geochemical anomalies related to a Mn-Fe deposit and associated Cu mineralization in west-central Sinai, Egypt

The west-central Sinai area includes one of the most productive manganese deposits in Egypt (Um Bogma Mn-Fe ore). The explored area is covered by a Carboniferous and Cambro-Ordovician sedimentary succession overlying Precambrian basement rocks. The purpose of this study is to delineate geochemical anomalies of ore and related elements and track their dispersion trains, which may lead to the discovery of unknown ore deposits. For this purpose, 143 stream sediment samples were analysed and the data were interpreted using the concentration–number (C-N) fractal model, factor analysis and the geochemical mineralization probability index (GMPI). Geochemical thresholds obtained from the C-N fractal model, factor scores and GMPI were used for constructing geochemical anomaly maps and delineating probable anomalous sites. The spatial distribution of Mn, Cu, Co, Pb and Zn anomalies was correlated to Mn and Cu mineralization sites whereas those of Fe and Cr were consistent with mafic rock distributions. Factor analysis revealed significant element associations for mineralization (Cu, Co, Mn, Zn, Pb), country rock composition (Fe, Cr) and element mobility (Cd, Zn). The spatial distribution of ore elements (Mn, Cu) delineated by the factor score and GMPI distribution maps was confirmed and more accurately interpreted using geochemical anomaly maps constructed based on the fractal-derived thresholds. Based on the current study, recent Cu and Mn mineralization sites may be suggested. Cobalt, Zn, Pb and Cd are suggested as efficient pathfinder elements for marine Mn deposits. A dispersion sequence of Cd>Mn>Co>Pb>Zn>Cu>Cr>Fe was proposed based on the threshold distribution patterns of these elements. Supplementary material: Tables S1–S3 and Figures S1 and S2 are available at https://doi.org/10.6084/m9.figshare.c.5463511

The application of threshold gold values based on geochemical exploration in complex regolith terrains: A case study at Lawra Greenstone Belt of Northwest Ghana

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Integrated geophysical investigation for mapping of manganese-iron deposits at Wadi Al Sahu area, Sinai, Egypt—a case study

This study used data from an investigation into the mapping of manganese-iron (Mn-Fe) mineralization, located within the Um Bogma formation. The ore takes the form of patchy isolated bodies or lenses in the three members of the Um Bogma formation located in East Sinai, Egypt. Magnetic, resistivity, and induced polarization (IP) surveys were applied at the Wadi Al Sahu area to delineate the mineralized ore bodies in terms of depth and extension. The quantitative interpretation of magnetic data was carried out using the 2D analytical signal. The results of the magnetic interpretation indicated that the depths of such ore deposits range from − 2 to − 20 m, and the shape of the magnetized units (assumed to be manganese-iron ore) is lenticular and of small size ranging from 20 to 100 m in width. Three dipole-dipole geo-electrical traverses were carried out along the anomalous sites, the traverse locations selected from the constructed magnetic maps of the study area, and the resistivity and IP measurements along with them. The results of the resistivity and IP inversion indicate that there are conductive and chargeable bodies at a depth that indicate the shape of small Mn-Fe lenses being present and conform to the shape of the Mn-Fe ore mineralization. Integration between the magnetic and geo-electrical data is made to lessen the non-uniqueness problem in geophysical prospecting. In this case, we used electrical resistivity and induced polarization models to delineate the boundaries between different geo-electric units, and these boundaries were used as interfaces between layers with different magnetic susceptibility for magnetic modeling to perform magnetic data inversions.

Hydrogeochemical Characters of Karst Aquifers in Central Italy and Relationship with Neotectonics

Groundwater from karst circulation systems of Central Italy were sampled and analyzed, in 2018, for delineating a preliminary, general geochemical framework of their relationship with neotectonics, in an area characterized by a frequent and often destructive seismicity. We determined field physical-chemical parameters, concentrations of main dissolved ions and gases and isotopic composition of water (δ18O, δD) and total dissolved inorganic carbon (δ13C TDIC). We discriminated between “normal” hydro-karst systems and multi-component aquifers, composed of meteoric groundwater that have also interacted with rocks of different lithological nature and/or deep fluids. These multicomponent aquifers are of potential interest in the monitoring of neotectonics activity, because changes in the stress field associated with the preparatory phase of an earthquake may affect the permeability of rocks, in turn causing variation of their chemical-isotopic character. The geographical distribution of these aquifers seems to be controlled by tectonics. In fact, the Olevano–Antrodoco–Sibillini thrust separates the more anomalous sites, located westwards of it, from the groundwater bodies at its eastern side, showing a more typical karst character.

Ecological and geochemical assessment of the soil in Perm

Based on the results of environmental and analytical studies, the level of chemical pollution of urban soils with trace elements of 1, 2, and 3 hazard classes and organic toxicants was assessed. Spatial mapping of ecological condition of the residential zone soils in Perm was performed, the allocation of anomalous sites being indicated.

Calibrating a new attenuation curve for the Dead Sea region using surface wave dispersion surveys in sites damaged by the 1927 Jericho earthquake

Abstract. Instrumental strong motion data are not common around the Dead Sea region. Therefore, calibrating a new attenuation equation is a considerable challenge. However, the Holy Land has a remarkable historical archive, attesting to numerous regional and local earthquakes. Combining the historical record with new seismic measurements will improve the regional equation. On 11 July 1927, a rupture, in the crust in proximity to the northern Dead Sea, generated a moderate 6.2 ML earthquake. Up to 500 people were killed, and extensive destruction was recorded, even as far as 150 km from the focus. We consider local near-surface properties, in particular, the shear-wave velocity, as an amplification factor. Where the shear-wave velocity is low, the seismic intensity far from the focus would likely be greater than expected from a standard attenuation curve. In this work, we used the multichannel analysis of surface waves (MASW) method to estimate seismic wave velocity at anomalous sites in Israel in order to calibrate a new attenuation equation for the Dead Sea region. Our new attenuation equation contains a term which quantifies only lithological effects, while factors such as building quality, foundation depth, topography, earthquake directivity, type of fault, etc. remain out of our scope. Nonetheless, about 60 % of the measured anomalous sites fit expectations; therefore, this new ground-motion prediction equation (GMPE) is statistically better than the old ones. From our local point of view, this is the first time that integration of the 1927 historical data and modern shear-wave velocity profile measurements improved the attenuation equation (sometimes referred to as the attenuation relation) for the Dead Sea region. In the wider context, regions of low-to-moderate seismicity should use macroseismic earthquake data, together with modern measurements, in order to better estimate the peak ground acceleration or the seismic intensities to be caused by future earthquakes. This integration will conceivably lead to a better mitigation of damage from future earthquakes and should improve maps of seismic hazard.

Sampling Density in Regional Exploration and Environmental Geochemical Studies: A Review

A variety of factors contribute to the proper and efficient evaluation of geochemical programs including sampling medium, sample size and sample fraction, sampling density, digestion procedure, and analytical techniques. Among the aforementioned factors, sampling density is of great importance, affecting project ability to detect anomalous sites, which are either economically viable or environmentally hazardous. It is quite critical to have a sufficient number of samples to delineate geochemical anomalies or baselines and to reveal the relative variations in elemental concentrations in a study area. The resolution of the subsequent maps obtained by sampling greatly depends on sampling density. While a large number of samples may generate redundant data, a small number of samples smooth out the patterns and may completely miss anomalies. This review provides a platform for applied geochemists who desire to design a sampling scheme for a regional geochemical program and do not have the financial resources to perform an orientation survey, which will give them the necessary information for designing, according to project objectives, a cost-effective regional geochemical survey for their study area. It is advisable to integrate during the desktop study all available information, such as geological, structural, geophysical, remote sensing data and topographical data by using different data fusion algorithms to arrive at a sampling density fit-for-purpose of the target area. This in turn facilitates an effective spatial positioning of sample locations. Quantitative analyses of the efficiency of different sampling densities for delineating geochemical patterns have not been well documented, warranting more attention and research.

Geochemical Characteristics and Radioactive Elements Estimation along Trenches of Um Ara area, South Eastern Desert, Egypt

Um Ara area is located in the extreme south Eastern Desert of Egypt between 581400mE-584900mE and 2503000mN-2504600mN. The area comprises distinct tectono-stratigraphic units beginning with the oldest as follows: Dokhan volcanic and post-collision granitoids (monzogranite, and alkali feldspar granite), and associated with dykes and quartz veins. The granite affected by deuteric K-metasomatism (microclinization) followed by Na-metasomatism (albitization) causing zonation in this part of the pluton. The high radioactivity in the anomalous sites is structurally controlled (strong shearing, fracturing and jointing). The intensity of mineralization is especially significant along joint sets striking NNW-SSE, NNESSW and NE-SW trending. The spacing among these joints ranges from few mm up to about 5 cm. locally, the joints are filled with kaolinite and other alteration products including hematite and Mnoxides. Geochemically, Um Ara granites trenches and core samples show a relative enrichment in K2O compositions due to plagioclase destruction and formation of muscovite/sericitization. Um Ara granites trenches and core samples have variable total REEs contents 117.41 to 308.28 and 256.51 to 397.22 ppm respectively. ΣLREEs in trenches and core samples range from 108.47 to 298.41ppm and from 236.84 to 384.78 ppm respectively, whereas ΣHREEs range from 5.48 to 14.01 ppm and from 12.44 to 19.67 ppm respectively. The lowest concentration of total REEs in core samples is at 100m depth, while the highest values at 145m depth. Um Ara granites trenches, U contents vary from 154 to 506 ppm with an average of 245.7 ppm, and Th contents vary from 47 to 415 ppm with an average of 165.4 ppm. Core samples granite, U contents vary from 128 to 349 ppm with an average of 237.3 ppm, and Th contents vary from 45 to 146 ppm with an average 107.4 ppm. Visible secondary uranium mineralization is represented mainly by uranophane and β-uranophane. Uranium is also contained within a range of U-bearing accessory minerals, mainly fluorite, monazite, xenotime, allanite and zircon. The secondary processes played a main role in uranium enrichment (uranium added to these granitic sites post-magmatically). Um Ara altered granites trenches and core samples rocks are an abnormal radiation and have an extension. So, these anomalies are suitable to be a place for uranium extraction. The result is the continuous of its mining work besides leachability experiments.

Histological verification of atherosclerosis due to bends and bifurcations in carotid arteries predicted by hemodynamic model.

Background Tortuosity and bifurcations in carotid arteries alter the blood flow, causing atherosclerosis. Objectives The aim of the present study is to analyze the effect of variant vascular anatomy in the cervical region on development of atherosclerosis by microanatomical examination. Methods The effect of blood flow at anomalous bends and bifurcations was observed in right carotid arteries of a seventy year old female cadaver. Fifteen histological slides were prepared from the carotid arteries and interpreted to verify predictions of atherosclerosis. Results The model predicts atherosclerosis at bends, bifurcations and large aperture arteries. Microanatomical examination revealed presence of atherosclerosis of varying thickness at the bends and bifurcation in the right carotid arteries, as predicted. Atherosclerosis was also detected in the straight part of the wider common carotid artery. No atherosclerosis was observed in the contralateral carotid arteries. The variant carotid vascular anatomy consisting of bends, bifurcations and wider arteries revealed that the shear stress and velocity of blood flow are reduced at these anomalous sites. Conclusions Anatomical anomalies such as bends and branching in the carotid arteries alter the irrigation pattern and generate biomechanical forces that cause turbulent flow and reduce shear stress/blood flow velocity. Decreased shear stress and velocity causes development of atherosclerosis. Histological slides established the presence of atherosclerosis at bends and bifurcations and in wider arteries.

The Egyptian geomagnetic reference field to the Epoch, 2010.0

The present work is a compilation of two tasks within the frame of the project “Geomagnetic Survey & Detailed Geomagnetic Measurements within the Egyptian Territory” funded by the “Science and Technology Development Fund agency (STDF)”. The National Research Institute of Astronomy and Geophysics (NRIAG), has conducted a new extensive land geomagnetic survey that covers the whole Egyptian territory. The field measurements have been done at 3212 points along all the asphalted roads, defined tracks, and ill-defined tracks in Egypt; with total length of 11,586km. In the present work, the measurements cover for the first time new areas as: the southern eastern borders of Egypt including Halayeb and Shlatin, the Quattara depresion in the western desert, and the new roads between Farafra and Baharia oasis. Also marine geomagnetic survey have been applied for the first time in Naser lake.Misallat and Abu-Simble geomagnetic observatories have been used to reduce the field data to the Epoch 2010. During the field measurements, whenever possible, the old stations occupied by the previous observers have been re-occupied to determine the secular variations at these points.The geomagnetic anomaly maps, the normal geomagnetic field maps with their corresponding secular variation maps, the normal geomagnetic field equations of the geomagnetic elements (EGRF) and their corresponding secular variations equations, are outlined. The anomalous sites, as discovered from the anomaly maps are, only, mentioned. In addition, a correlation between the International Geomagnetic Reference Field (IGRF) 2010.0 and the Egyptian Geomagnetic Reference Field (EGRF) 2010 is indicated.

PAHs behavior in surface water and groundwater of the Yellow River estuary: Evidence from isotopes and hydrochemistry

Large-scale irrigation projects have impacted the regional surface-groundwater interactions in the North China Plain (NCP). Given this concern, the aim of this study is to evaluate levels of PAH pollution, identify the sources of the PAHs, analyze the influence of surface–groundwater interactions on PAH distribution, and propose urgent management strategies for PAHs in China’s agricultural areas. PAH concentrations, hydrochemical indicators and stable isotopic compositions (δ18O and δ2H) were determined for surface water (SW) and groundwater (GW) samples. PAHs concentrations in surface water and groundwater varied from 11.84 to 393.12 ng/L and 8.51–402.84 ng/L, respectively, indicating mild pollution. The seasonal variations showed the following trend: PAHs in surface water at the low-water phase > PAHs in groundwater at the low-water phase > PAHs in surface water at the high-water phase > PAHs in groundwater at the high-water phase. Hydrochemical and δ18O value of most groundwater samples distributed between the Yellow River and seawater. The mean value of mixture ratio of the Yellow River water recharge to the groundwater was 65%, few anomalous sites can reach to 90%. Surface–groundwater interactions influence the spatial distribution of PAHs in the study area. In light of the ongoing serious pollution, management practices for source control, improved control technologies, and the construction of a monitoring network to warn of increased risk are urgently needed.

Mineralogy and radioactivity of anomalous sites of Wadi Murrah post-collision granites, south Eastern Desert, Egypt

Wadi Murrah area is located in the extreme south Eastern Desert of Egypt. The area comprises four distinct tectono-stratigraphic units beginning with the oldest as follows: ophiolitic assemblage (dismembered ophiolitic rocks and ophiolitic melange), arc assemblage (metavolcanics, metagabbros, and older granites), post-collision granitoids (monzogranite, syenogranite, and alkali feldspar granite), and associated with dykes and quartz veins. The identified minerals in the samples taken from the anomalous sites of syenogranite and alkali feldspar granite in the northern part of the study area are represented by uranophane, autonite, meta-autonite, uranothorit, columbite, zircon, fluorite, monazite, xenotime, sphene, allanite, and apatite. The anomalous samples have U and Th average contents for syenogranites and alkali feldspar granites 82 and 104.4 ppm and 209 and 115.2 ppm, respectively. The high radioactivity in the anomalous sites is controlled lithologically and structurally. The secondary processes played a main role in uranium enrichment (uranium added to these granitic sites post-magmatically).

Multivariate analysis of regolith sediment geochemical data from the Jinwozi gold field, north-western China

The study of deep-penetrating geochemistry of arid desert terrains in the Jinwozi gold field, north-western China has generated a data set of multi-element geochemistry, characterised by high complexity and variability leading to difficulties in integration and interpretation. Three multivariate statistical methods, i.e., factor analysis (FA), hierarchical cluster analysis (HCA) and discriminant analysis (DA) were applied to a subgroup of the data set in order to define the element associations, to identify the anomalies and to classify the regolith samples. The geochemical patterns of arid desert terrains were thus interpreted with the aid of statistical techniques. The subgroup consists of Au, Ag, As, Hg, Cu, Mo, Sb and Zn concentrations of regolith samples collected from two traverse lines and five overburden boreholes. Two factors with eigenvalues greater than 1 extracted by FA account for approximately 81% of the total variance. Specifically, factor 1 explains 52% of the total variance and is highly loaded by a combination of Au–As–Hg–Ag. This combination could represent the major mineralisation and three anomalous sites have been determined. Two of which are located over the known deposit. Factor 2 explains 29% of the total variance and has positive loadings on Cu and Zn denoting the minor mineralisation and diagenesis. High positive scores of both factors could be considered as an indication of the mineralisation. Silver, As, Cu and Zn are the most effective indirect indicator elements in the Jinwozi. The HCA was then applied to the classification of samples taken from the five boreholes at the three anomalous sites. Three geochemically distinct clusters, named A1, A2 and A3, resulted from the HCA. Samples from cluster A1 with high concentrations of Au, Ag, As, Hg, Cu and Zn are highly-mineralised. In addition, samples from cluster A2 and A3 can be generally treated as non-mineralised. The DA confirmed the results obtained from the HCA. The spatial distribution of the clusters shows vertical symmetric distribution of highly-mineralised samples over the deposit. This confirms the effectiveness of the FA in delineation of the anomalies in the Jinwozi. The integration of the FA, HCA and DA proved to be an effective tool in the field of deep-penetrating geochemistry.

Crystal Structure of the Ectodomain Complex of the CGRP Receptor, a Class-B GPCR, Reveals the Site of Drug Antagonism

Dysregulation of the calcitonin gene-related peptide (CGRP), a potent vasodilator, is directly implicated in the pathogenesis of migraine. CGRP binds to and signals through the CGRP receptor (CGRP-R), a heterodimer containing the calcitonin receptor-like receptor (CLR), a class B GPCR, and RAMP1, a receptor activity-modifying protein. We have solved the crystal structure of the CLR/RAMP1 N-terminal ectodomain heterodimer, revealing how RAMPs bind to and potentially modulate the activities of the CLR GPCR subfamily. We also report the structures of CLR/RAMP1 in complex with the clinical receptor antagonists olcegepant (BIBN4096BS) and telcagepant (MK0974). Both drugs act by blocking access to the peptide-binding cleft at the interface of CLR and RAMP1. These structures illustrate, for the first time, how small molecules bind to and modulate the activity of a class B GPCR, and highlight the challenges of designing potent receptor antagonists for the treatment of migraine and other class B GPCR-related diseases.

Hot/Cold Spots in Italian Macroseismic Data

The site effect is usually associated with local geological conditions, which increase or decrease the level of shaking compared with standard attenuation relations. We made an attempt to see in the macroseismic data of Italy some other effects, namely, hot/cold spots in the terminology of Olsen (2000), which are related to local fault geometry rather than to soil conditions. We give a list of towns and villages liable to amplify (+) or to reduce (-) the level of shaking in comparison with the nearby settlements. Relief and soil conditions cannot always account for the anomalous sites. Further, there are sites where both (+) and (-) effects are observed depending on the earthquake. The opposite effects can be generated by events from the same seismotectonic zone and along the same direction to the site. Anomalous sites may group themselves into clusters of different scales. All isolated anomalous patterns presented in this paper can be used in hazard analysis, in particular, for the modeling and testing of seismic effects.

Geophysical exploration for gold and associated minerals, case study: Wadi El Beida area, South Eastern Desert, Egypt

The occurrences of gold and disseminated sulfides lie as a part of the shearing fault zone that extends from the north to the south of the study area for a length of about 25 km. The gold and disseminated sulfides are located on the alteration shear zone which is composed of quartz–feldspathic highly ferruginated rock (gossans) occupying the eastern and central parts of the area. Mineralogical analyses that were done on bedrock samples of the oxidized and alteration zones indicated that there are two anomalous spots of gold contents; the first one has values ranging from 5 to 49 g ton−1 and the second anomaly has values ranging from 150 to 502.5 g ton−1. Magnetic, self-potential, resistivity and induced polarization surveys were applied at Wadi El Beida area to delineate the mineral ore deposits in terms of depths and extensions through the structural shearing zone. The quantitative interpretation of magnetic data was carried out by using two techniques; the first is 3D magnetic inversion using Euler deconvolution and the second is magnetic models using the MAGMOD program. The results of the magnetic interpretation indicated that the depths of such ore deposits range from 35.9 to 52.7 m and the half width ranged from 27.2 to 87.8 m. The SP contour maps show negative anomalies with ranges from −70 to 20 mV. Most of these anomalies occupy the shear, silicified zones, alterations and rock contacts. The SP anomalies are correlated with other geophysical ones and also with the geological sources. Quantitative interpretation was done on the selected anomalies along the coded lines on the normal SP contour map. The quantitative interpretation of self-potential anomalies (SP) was carried out using two techniques; the first is a new algorithm constructed by Monteiro Santos (2009) using particle swarm optimization (PSO) and the second is the code constructed by Caglar (2000). The depths range from 20 to 60 m. The gradient resistivity survey was carried out simultaneously with IP measurements. The low-resistivity zones coincide with the altered and sheared acidic meta-volcanics. The quantitative interpretation technique determined the conductive bodies' parameters using the Schulz method (1985) where the depth to the top of the ore body ranged from 21 to 62 m while the maximum width ranged from 52 to 165 m. The induced polarization-chargeability data were measured in the time domain. The positive anomalies on the IP-chargeability map coincide with the sites of alterations, shears and contact zones. Four dipole–dipole sections were carried out along the anomalous sites selected from the constructed maps in the study area and were inverted using the RES2DINV program. The results of resistivity and IP inversions indicated that there are conductive and chargeable bodies at depths ranging from 15 to 65 m. According to the integrated geophysical results, two suggested borehole sites were selected before carrying out any future mining projects.

Angioedema: 6 years experience with fourteen cases

Objective To study the difference in the findings between the causes of angioedema and the characteristics of angioedema induced by angiotensin receptor II blockers (ARBs), and to investigate whether laboratory examinations for acute phase inflammatory markers can aid in diagnosis and predict airway risk. Methods We retrospectively reviewed fourteen cases of patients with angioedema that were treated from 2000 to 2006. Data were collected regarding age, sex, location of the edema, cause, time course of resolution and laboratory examinations (leukocyte counts, serum C-reactive protein (CRP) level, complement function and the activity of C1 esterase inhibitor). Results The causes of angioedema were ACEIs in six patients (42.9%), candesartan (ARB) in three (21.4%), HAE (types 1 and 2) in two, and unknown in three. Of these patients, 71.4% exhibited edema in the floor of the mouth, irrespective of the cause. Two patients with edema induced by candesartan exhibited both lingual and laryngeal edemas. The remaining one with candesartan-induced edema exhibited edema in the neck and mediastinum and pleural effusion. The average time to resolution was 4.1 days, ranging from one to twelve days. The edema in eleven patients resolved with conservative therapy, while three patients underwent tracheotomy. In two patients with candesartan-induced edema, although the edemas resolved completely after cessation of candesartan administration, the edemas reappeared in the same locations, two and thirty days after the cessation of candesartan for each patient. None of the patients with angioedema induced by ACEIs exhibited elevation of serum CRP levels. No significant differences were found for leukocyte counts and serum CRP levels between patients with angioedemas induced by ACEIs, ARB and those of unknown cause. No significant differences were observed in the above findings between the patients who underwent tracheotomy and those who did not. Two patients exhibited low C4 levels, and one of the two exhibited no activity of C1 esterase inhibitor. Conclusion Consistent with previous reports, angioedema in the floor of the mouth extending to the tongue should be considered as a possible risk factor for airway compromise. Laboratory examinations for acute phase inflammatory markers are not useful for diagnosis and are not predictive for airway intubation and tracheotomy. Angioedema induced by candesartan can present in anomalous sites and reappear following drug cessation even if the edema has resolved completely.