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Journal of African earth sciences 37건

  1. [해외논문]   Hydrogeological framework and geometry modeling via joint gravity and borehole parameters, the Nadhour-Sisseb-El Alem basin (central-eastern Tunisia)   SCIE

    Souei, Ali (Laboratoire de Géoressources, CERTE, Pôle Technologique de Borj Cédria, 8020 Soliman, Tunisia ) , Atawa, Mohamed (Laboratoire de Géoressources, CERTE, Pôle Technologique de Borj Cédria, 8020 Soliman, Tunisia ) , Zouaghi, Taher (Geoexploration Department, Faculty of Earth Sciences, King Abdulaziz University, 21589 Jeddah, Saudi Arabia)
    Journal of African earth sciences v.139 ,pp. 133 - 164 , 2018 , 1464-343x ,

    초록

    Abstract The Nadhour-Sisseb-El Alem basin, in the central-eastern part of Tunisia, is characterized by the scarcity of surface and subsurface water resources. Although the aquifer systems of this basin are not well understood, the scarce water resources are subject to a high rate of exploitation leading to a significant drop in the level of the water table. This work presents correlation of gravity data with hydrogeological data in order to improve the knowledge of the deep structures and aquifer systems. Various geophysical filtering techniques (e.g., residual anomaly, upward continuation, horizontal gradient, and Euler deconvolution) applied to the complete Bouguer anomaly, deduce the deep structures and geometry of the basin and highlight gravity lineaments that correspond to the tectonic features. The structural framework of the Nadhour-Sisseb-El Alem hydrogeological basin shows N-S to NNE-SSW and E-W oriented structures that should be related to tectonic deformations. In addition to the faults, previously recognized, new lineaments are highlighted by the present work. They correspond to NE-, NW-, E- and N- trending faults that have controlled structuring and geometry of the basin. 2D gravity forward modeling, based on the interpretation of geophysical, geological and hydrogeological data, led to a better understanding of the basin geometry and spatial distribution of the Campanian-Maastrichtian and Cenozoic potential aquifers. Three hydrogeological sub-basins identified include the Nadhour sub-basin in the north, the El Alem sub-Basin in the South and the Etrabelsia sub-Basin in the East. These sub-basins are marked by a thickening of deposits, are separated by the Sisseb-Fadeloun raised structure of Neogene and Quaternary thinned series. The results allow the determination of limit conditions for the basin hydrodynamic evolution and explain some anomalies on the quantity and quality of the groundwater. They provide a management guide for water resources prospection in Atlassic basins in North Africa. Highlights The work proposed hydrogeological models for the Nadhour-Sisseb-El Alem basin. The work proposes structural framework related the geodynamic evolution and filling. NE-, N-, NW-, and E-striking faults subdivide the study area into differential sub-basins. 2D gravity forward modeling provides the geometry of deep aquifers for each unit. Results guide the management of the water resources to new areas of prospect.

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  2. [해외논문]   Study of Zn-Pb ore tailings and their potential in cement technology   SCIE

    Nouairi, J. (Dept of Geology, Faculty of Sciences of Sfax, 3018, Sfax, Tunisia ) , Hajjaji, W. (LabTEN Natural Water Treatment Laboratory, CERTE, BP 273, 8020 Soliman, Tunisia ) , Costa, C.S. (Geobiotec, Geosciences Dept, University of Aveiro, 3810-193, Aveiro, Portugal ) , Senff, L. (Center of Mobility Engineering, Federal University of Santa Catarina (UFSC), Joinville, SC, Brazil ) , Patinha, C. (Geobiotec, Geosciences Dept, University of Aveiro, 3810-193, Aveiro, Portugal ) , Ferreira da Silva, E. (Geobiotec, Geosciences Dept, University of Aveiro, 3810-193, Aveiro, Portugal ) , Labrincha, J.A. (Department of Materials and Ceramic Engineering / CICECO, Aveiro Institute of Materials, University of Aveiro, Aveiro, 3810-193, Portugal ) , Rocha, F. (Geobiotec, Geosciences Dept, University of Aveiro, 3810-193, Aveiro, Portugal ) , Medhioub, M. (Dept of Geology, Faculty of Sciences of Sfax, 3018, Sfax, Tunisia)
    Journal of African earth sciences v.139 ,pp. 165 - 172 , 2018 , 1464-343x ,

    초록

    Abstract This paper describes the synthesis of sulfobelite clinkers incorporating mining rejects. The targeted Zn-Pb tailing wastes generated in the diapiric zone (NW Tunisia) were tested in clinker/cement compositions to ensure the inertization of existing hazardous heavy metals. Mineralogical composition of the two selected samples revealed calcite, dolomite, quartz, kaolinite, galena, pyrite and gypsum as crystalline phases. Vertical distributions of dominant heavy metals (Pb, Zn and Cu) in soil profiles show enrichment in the surface layers and decrease towards the depth. In sintered clinkers powders, the presence of the targeted crystalline phases (trialuminate sulphate (C4A3Š), belite (C2S), and ferrite (C4AF)) are in the predicted desirable amounts. Heat flow generated during the hydration of different cement pastes showed a slower reaction for clinkers with higher amounts of C 4 A 3 Š or constituted by coarser particles. After 28 days curing, the best mechanical resistance (24.34 MPa under compression) was obtained for the clinker calcined at 1350 °C and showing a suitable particle size distribution. Concerning heavy metals, immobilisation of 75–85% of Pb, Zn and Cu was assessed in the mortars formulated with the produced clinker/cement, posing no hazardous risks to the environment. Highlights The synthesis of sulfobelite clinkers is incorporating mining rejects. Clinkers are composed of C 4 A 3 Š, C 2 S, and C 4 AF as predicted by initial formulations. Mechanical strength reached high values after 28 days curing, superior to 15 MPa. Pb, Zn and Cu heavy metals immobilisation was superior to 75% in produced mortars.

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  3. [해외논문]   Geochemical modeling of orogenic gold deposit using PCANN hybrid method in the Alut, Kurdistan province, Iran   SCIE

    Mohammadzadeh, Mohammadjafar (Faculty of Mining Engineering, Sahand University of Technology, Tabriz, Iran ) , Nasseri, Aynur (Department of Mining Engineering, Ahar Branch, Islamic Azad University, Ahar, Iran)
    Journal of African earth sciences v.139 ,pp. 173 - 183 , 2018 , 1464-343x ,

    초록

    Abstract In this paper stream sediments based geochemical exploration program with the aim of delineating potentially promising areas by a comprehensive stepwise optimization approach from univariate statistics, PCA, ANN, and fusion method PCANN were under taken for an orogenic gold deposit located in the Alut, Kurdistan province, NW of Iran. At first the data were preprocessed and then PCA were applied to determine the maximum variability directions of elements in the area. Subsequently the artificial neural network (ANN) was used for quick estimation of elemental concentration, as well as discriminating anomalous populations and intelligent determination of internal structure among the data. However, both the methods revealed constraints for modeling. To overcome the deficiency and shortcoming of each individual method a new methodology is presented by integration of both “PCA & ANN” referred as PCANN method. For integrating purpose, the detected PCs pertinent to ore mineralization selected and intruded to neural network structure, as a result different MLPs with various algorithms and structures were produced. The resulting PCANN maps suggest that the gold mineralization and its pathfinder elements (Au, Mo, W, Bi, Sb, Cu, Pb, Ag & As) are associated with metamorphic host rocks intruded by granite bodies in the Alut area. In addition, more concealed and distinct Au anomalies with higher intensity were detected, confirming the privileges of the method in evaluating susceptibility of the area in delineating new hidden potential zones. The proposed method demonstrates simpler network architecture, easy computational implementation, faster training speed, as well as no need to consider any primary assumption about the behavior of data and their probability distribution type, with more satisfactory predicting performance for generating gold potential map of the area. Comparing the results of three methods (PCA, ANN and PCANN), representing the higher efficiency and more reliability of PCANN with lesser training time, simple structure, and correlate components while avoiding the duplicate entry of data to network. This study also suggests that in many similar cases integrated methods have capability to fix bugs more effectively and successfully in exploration programs. Highlights Stepwise optimization fused PCANN method proposed for potential mapping of Orogenic gold deposit. Privileges of model includes; simpler structure, easy implementation, lesser training time, higher performance for generating gold potential map. The resulting PCANN maps suggest; higher Au concentration with lower sulphide threshold indicating metamorphic rocks as Au fluid source and granitoid intrusion as heat source. Proper implementation of the method characterized Au distribution pattern for vectoring exploration targets.

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  4. [해외논문]   Geophysical investigation using gravity data in Kinigi geothermal field, northwest Rwanda   SCIE

    Uwiduhaye, Jean d'Amour (Rwanda Energy Group Limited, 3855 Kigali, Rwanda ) , Mizunaga, Hideki (Department of Earth Resources Engineering, Faculty of Engineering, Kyushu University, Fukuoka, 819-0395, Japan ) , Saibi, Hakim (Department of Earth Resources Engineering, Faculty of Engineering, Kyushu University, Fukuoka, 819-0395, Japan)
    Journal of African earth sciences v.139 ,pp. 184 - 192 , 2018 , 1464-343x ,

    초록

    Abstract A land gravity survey was carried out in the Kinigi geothermal field, Northwest Rwanda using 184 gravity stations during August and September, 2015. The aim of the gravity survey was to understand the subsurface structure and its relation to the observed surface manifestations in the study area. The complete Bouguer Gravity anomaly was produced with a reduction density of 2.4 g/cm 3 . Bouguer anomalies ranging from −52 to −35 mGals were observed in the study area with relatively high anomalies in the east and northwest zones while low anomalies are observed in the southwest side of the studied area. A decrease of 17 mGals is observed in the southwestern part of the study area and caused by the low-density of the Tertiary rocks. Horizontal gradient, tilt angle and analytical signal methods were applied to the observed gravity data and showed that Mubona, Mpenge and Cyabararika surface springs are structurally controlled while Rubindi spring is not. The integrated results of gravity gradient interpretation methods delineated a dominant geological structure trending in the NW-SE, which is in agreement with the regional geological trend. The results of this gravity study will help aid future geothermal exploration and development in the Kinigi geothermal field. Highlights Gravity lineaments are extracted and interpreted to be the density boundaries. The interpreted faults are mainly oriented in NW-SE trend. The estimated fault from 3-D simulation is located near the two fault lines that were estimated by horizontal gradient. Mubona, Mpenge and Cyabararika surface springs are structurally controlled while Rubindi spring is not. The agreement in the results shows the reliability of the interpreted faults.

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  5. [해외논문]   Combining satellite image data and field observations to characterize fresh-water carbonates in Kurkur Oasis, Southern Egypt   SCIE

    Gaber, Ahmed (Port-Said University, Dept. of Geology, Port-Said, Egypt ) , Khalaf, Fikry (Port-Said University, Dept. of Geology, Port-Said, Egypt ) , Bastawisy, Mohamed (National Authority of Remote Sensing and Space Science (NARSS), Cairo, Egypt ) , El-Baz, Farouk (Boston University, Center for Remote Sensing, Boston, MA, USA)
    Journal of African earth sciences v.139 ,pp. 193 - 204 , 2018 , 1464-343x ,

    초록

    Abstract Several fresh-water carbonate deposits (tufa and travertine) were formed at different elevations within the Kurkur paleolake, 50 km west of Aswan, Egypt. Such paleolake was unique and confined in sag between the cuesta and the capping platform of Sin El-Kaddabaa Plateau. This work aims at integrating the remote sensing data together with the chemical and petrographic analyses to map and characterize these tufa and travertine deposits to define their paleo-depositional environment. A DEM with 2.5 m spatial resolution was generated from two ALOS/PRISM images to show geomorphological and hydrological parameters. In addition, full-polarimetric SAR data were used to investigate the scattering response of these tufa and travertine deposits. These deposits show a volume scattering response, with an increase in the pedestal height of the co- and cross-polarized signatures. The tufa and travertine deposits range from Pleistocene (older upper level) to Recent (younger lower level). The young tufa is hard, light brown porous and thinly-laminated, while the old tufa is generally coarse crystalline and consists of columnar pseudo denderitic calcite crystals. The travertine displays a stromatolitic fabric, where thin dark micritic algal laminae alternate with relatively thick calcitic bands (∼1 cm). Conducted XRD and chemical analyses reveal that these tufa and travertine are entirely composed of low magnesium calcite, with traces of quartz ( 13 C and δ 18 O values suggest that the old tufa have been developed during warm pluvial periods, while the younger ones were precipitated in drier periods. Two hypotheses were introduced to explain the changes in the hydrological regime of Kurkur paleolake; the first proposes a hydrological breaching due to water overflow on the lake's low periphery areas that led to their desiccation (where the tufa and travertine were deposited) and the second is the possible integration into the regional drainage networks of the area presently occupied by Lake Nasser. Highlights High resolution DEM with 2.5 m was generated using ALOS/PRISM. The radar's scattering response of tufa and travertine were investigated. Thin section, XRD and isotopic analyses were performed. A suggested model of the development of these deposits was proposed. Two main hypotheses are introduced to explain their hydrological changes.

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  6. [해외논문]   Sequence stratigraphy of the Raha Formation, Bakr Oil Field, Gulf of Suez, Egypt: Insights from electrical well log and palynological data   SCIE

    Mansour, Ahmed (Geology Department, Faculty of Science, Minia University, P.O. Box 61519, Minia, Egypt ) , Mohamed, Omar (Geology Department, Faculty of Science, Minia University, P.O. Box 61519, Minia, Egypt ) , Tahoun, Sameh S. (Geology Department, Faculty of Science, Cairo University, P.O. Box 12613, Giza, Egypt ) , Elewa, Ashraf M.T. (Geology Department, Faculty of Science, Minia University, P.O. Box 61519, Minia, Egypt)
    Journal of African earth sciences v.139 ,pp. 205 - 221 , 2018 , 1464-343x ,

    초록

    Abstract The current paper provides a high resolution sequence stratigraphic study of the Raha Formation from the productive Bakr Oil Field, central Gulf of Suez, Egypt. Sixty cutting rock samples spanning the Cenomanian from three wells (Bakr-114, B-115 and B-109) in the Bakr Basin, were palynologically investigated. The documented palynomorphs assemblage of either terrestrially-derived sporomorphs or marine inhabited dinocysts, allowed two palynological zones as well as their encompassing depositional palaeoenvironment to be recognized. These zones are Afropollis jardinus–Crybelosporites pannuceus Assemblage Zone (early-middle Cenomanian) and Classopollis brasiliensis-Tricolpites sagax Assemblage Zone (late Cenomanian). Detailed analysis of the particulate organic matter compositions suggested that the depositional palaeoenvironment of the Raha Formation was fluctuating between supratidal and distal-inner neritic conditions, due to successive oscillations of the Neo-Tethyan Ocean during the Cenomanian. The pronounced peaks of particulate organic matter versus gamma ray are markedly used in delineating the depositional sequences of the Raha Formation and their bounding surfaces. The Raha Formation probably corresponds to a second-order depositional sequence, which can be further subdivided into eight third-order depositional sequences, of which six are complete and two are incomplete ones. These depositional sequences are significantly synchronized based on a simple 2-D correlation model between the three wells. According to the hierarchical duration system, the Cenomanian herein was approximately attributed to 6 Myr, each of which has lower order depositional sequences that took approximately 0.9 Myr. Based on the sequence stratigraphic approach together with palynofacies analysis and gamma ray data, a condensed section was defined in the B-115. Highlights Raha sequence framework is erected by combined lithologic, logs and palynologic data. Palynofacies data show long transgressive with short interrupting regressive phases. Raha corresponds to a 2nd order sequence, subdivided to eight sequences of 3rd order. The Raha Formation deposited within the continental shelf setting. Each 3rd order proposed sequence lasted approximately 0.9 Ma.

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  7. [해외논문]   Recent Niger Delta shoreline response to Niger River hydrology: Conflict between forces of Nature and Humans   SCIE

    Dada, Olusegun A. (Department of Marine Science and Technology, Federal University of Technology, Akure 340252, Nigeria ) , Li, Guangxue (College of Marine Geosciences & Key Lab of Submarine and Processing Techniques, Ocean University of China, Qingdao 266100, PR China ) , Qiao, Lulu (College of Marine Geosciences & Key Lab of Submarine and Processing Techniques, Ocean University of China, Qingdao 266100, PR China ) , Asiwaju-Bello, Yinusa Ayodele (Department of Applied Geology, Federal University of Technology, Akure 340252, Nigeria ) , Anifowose, Adeleye Yekini Biodun (Department of Remote Sensing and GIS, Federal University of Technology, Akure 340252, Nigeria)
    Journal of African earth sciences v.139 ,pp. 222 - 231 , 2018 , 1464-343x ,

    초록

    Abstract The Niger River Delta is a prolific hydrocarbon province and a mega-delta of economic and environmental relevance. To understand patterns of its recent shoreline evolution (1923–2013) in response to the Niger River hydrology, and establish the role played by forces of Nature and Human, available topographic and satellite remote sensing data, combined with hydro-climatic (rainfall and runoff) data were analyzed. Results indicate that the entire delta coastline dramatically receded: 82% of the >400 km-long coast retreated, during the period 1950–1987; and 69% between 2007 and 2012. Prior to 1950, there was a continuation of seaward advancement along 53–74% of the delta coast. The 1950–1987 shoreline recession coincided with occurrences of two major events in the Niger River basin; these are downward trends in hydro-climatic conditions (the great droughts of the 1970s-1980s), and dam construction on the Lower Niger River at Kainji (1964–1968). The 2007–2012 event corresponded with the extensive channel dredging during 2009–2012 in the Lower Niger River from the coastal town of Warri in the south to Baro in the north. Remarkably, the largest net shoreline advancement recorded in 74% of the entire delta area occurred within a year (2012–2013), which we link to increased sediment supply to the coast caused by the ‘2012’ floods, adjudged the worst floods in the entire Niger River Basin in the last few decades. With both anthropogenic and environmental factors inducing delta evolution, only innovative river and coastal management can determine the fortune of the future coastal development of the Niger Delta. Highlights We investigate Niger Delta shoreline evolution in response to river hydrology. We establish the role played by forces of Nature and Human activities. The 1950-87 shoreline recession coincides with droughts and dam construction. Shoreline erosion between 2007 and 2012 is attributed to Lower Niger River dredging. The largest net shoreline advancement is linked to the ‘2012’ floods.

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  8. [해외논문]   Recent Niger Δ shoreline response to Niger River hydrology: Conflict between forces of Nature and Humans  

    Dada, Olusegun A. , Li, Guangxue , Qiao, Lulu , Asiwaju-Bello, Yinusa Ayodele , Anifowose, Adeleye Yekini Biodun
    Journal of African earth sciences v.139 ,pp. 222 - 231 , 2018 , 1464-343x ,

    초록

    Abstract The Niger River Delta is a prolific hydrocarbon province and a mega-delta of economic and environmental relevance. To understand patterns of its recent shoreline evolution (1923–2013) in response to the Niger River hydrology, and establish the role played by forces of Nature and Human, available topographic and satellite remote sensing data, combined with hydro-climatic (rainfall and runoff) data were analyzed. Results indicate that the entire delta coastline dramatically receded: 82% of the >400 km-long coast retreated, during the period 1950–1987; and 69% between 2007 and 2012. Prior to 1950, there was a continuation of seaward advancement along 53–74% of the delta coast. The 1950–1987 shoreline recession coincided with occurrences of two major events in the Niger River basin; these are downward trends in hydro-climatic conditions (the great droughts of the 1970s-1980s), and dam construction on the Lower Niger River at Kainji (1964–1968). The 2007–2012 event corresponded with the extensive channel dredging during 2009–2012 in the Lower Niger River from the coastal town of Warri in the south to Baro in the north. Remarkably, the largest net shoreline advancement recorded in 74% of the entire delta area occurred within a year (2012–2013), which we link to increased sediment supply to the coast caused by the ‘2012’ floods, adjudged the worst floods in the entire Niger River Basin in the last few decades. With both anthropogenic and environmental factors inducing delta evolution, only innovative river and coastal management can determine the fortune of the future coastal development of the Niger Delta. Highlights We investigate Niger Delta shoreline evolution in response to river hydrology. We establish the role played by forces of Nature and Human activities. The 1950-87 shoreline recession coincides with droughts and dam construction. Shoreline erosion between 2007 and 2012 is attributed to Lower Niger River dredging. The largest net shoreline advancement is linked to the ‘2012’ floods.

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  9. [해외논문]   The assumed Aalenian stage-long eustatic lowstand did not exist: A review of the fresh evidence from Africa and other continents   SCIE

    Ruban, Dmitry A. (Southern Federal University, 23-ja linija Street 43, Rostov-na-Donu, 344019, Russia ) , Sallam, Emad S. (Department of Geology, Faculty of Science, Benha University, Farid Nada Street 15, Benha 13518, Egypt)
    Journal of African earth sciences v.139 ,pp. 232 - 240 , 2018 , 1464-343x ,

    초록

    Abstract The views of the Jurassic eustatic fluctuations differ significantly: specialists either suggest multiple rises and falls ("Haq's view") or question the idea of global falls ("Hallam's view"). For instance, it is unclear whether there was a stage-long eustatic lowstand in the Aalenian. The presence of the noted alternatives is a serious problem complicating interpretation of events in the geological history. This paper summarizes the evidence of the Aalenian long-term shoreline shifts obtained in different regions of the world since 2000, i.e., after the noted views appeared. This evidence deals with the stratigraphical architecture of regions (interpreted in the present article), the established shoreline shifts (transgressions and regressions), and the knowledge of the regional tectonic activity. The compiled information characterizes "stable" regions located in the different parts of the world (Europe, Asia, Africa, North America, South America, and Australia). It is established that there were no regressions in some of these regions in the Aalenian, whereas regressions in the other regions can be explained by the influence of the tectonic activity. There was no coherence of the basin-scale eustatically-driven regressions (in contrast, the long-term Bajocian eustatic rise is proven by a coherence of regional transgressions). This finding contradicts the idea of the stage-long eustatic lowstand in the Aalenian and, thus, favours the "Hallam's view". This interpretation is in agreement with the present knowledge of the Earth's palaeoclimate and the past plate tectonics. This study demonstrates efficacy of interregional correlation of sea-level changes for resolution of the problem of the alternative views of the Jurassic eustasy. Highlights Alternative views of Jurassic eustasy are discussed: rises and falls or only rises. The assumed Aalenian global stage-long sea-level lowstand is questioned. A compilation of "fresh" evidence from "stable" continental regions. No support is found for the idea of the Aalenian stage-long sea-level lowstand. Climate and tectonics were unfavourable for the Aalenian stage-long sea-level lowstand.

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  10. [해외논문]   The hydrogeochemical and isotopic investigations of the two-layered Shiraz aquifer in the northwest of Maharlou saline lake, south of Iran   SCIE

    Tajabadi, Mehdi (Department of Earth Sciences, College of Sciences, Shiraz University, Shiraz, 71454, Iran ) , Zare, Mohammad (Department of Earth Sciences, College of Sciences, Shiraz University, Shiraz, 71454, Iran ) , Chitsazan, Manouchehr (Department of Earth Sciences, Shahid Chamran University, Ahvaz, Iran)
    Journal of African earth sciences v.139 ,pp. 241 - 253 , 2018 , 1464-343x ,

    초록

    Abstract Maharlou saline lake is the outlet of Shiraz closed basin in southern Iran, surrounded by several disconnected alluvial fresh water aquifers. These aquifers in the west and northwest of the lake are recharged by karstic anticlines such as Kaftarak in the north and Barmshour in the south. Here groundwater salinity varies along the depth so that better quality water is located below brackish or saline waters. The aim of this study is to investigate the reason for the salinity anomaly and the origin of the fresher groundwater in lower depth. Hence, the change in groundwater salinity along depth has been investigated by means of a set of geoelectrical, hydrogeological, hydrogeochemical, and environmental isotopes data. The interpretation of geoelectrical profiles and hydrogeological data indicates that the aquifer in the southeast of Shiraz plain is a two-layer aquifer separated by a fine-grained (silt and clay) layer with an approximate thickness of 40 m at the depth of about 100–120 m. Hydrgeochemistry showed that the shallow aquifer is recharged by Kaftarak karstic anticline and is affected by the saline lake water. The lake water fraction varies in different parts from zero for shallow aquifer close to the karstic anticlines to ∼70 percent in the margin of the lake. The deep aquifer is protected from the intrusion of saline lake water due to the presence of the above-mentioned confining layer with lake water fraction of zero. The stable isotopes signatures also indicate that the ‘fresh’ groundwater belonging to the deep aquifer is not subject to severe evaporation or mixing which is typical of the karstic water of the area. It is concluded that the characteristics of the deep aquifer are similar to those of the karstic carbonate aquifer. This karstic aquifer is most probably the Barmshour carbonated anticline buried under the shallow aquifer in the southern part. It may also be the extension of the Kaftarak anticline in the northern part. Highlights Investigate the reason for the salinity anomaly along the depth. The shallow aquifer is affected by the saline lake water. The deep aquifer is protected from the intrusion of saline lake water due to the presence of confining layer.

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