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41.
Dr. Manouchehr Hakim 《International Journal of Earth Sciences》1980,69(2):384-396
Zusammenfassung Die Cu-Lagerstätte Sar Cheshmeh liegt im Süd-Iran in einer Vulkanitzone, die in 150 km Abstand nördlich parallel zur Zagrosüberschiebung verläuft. Die Lagerstätte ist an einen latitandesitischen bis rhyodazitischen Gesteinskomplex gebunden. Die auftretenden zonaren Vererzungen und hydrothermalen Alterationen des Nebengesteins weisen auf eine porphyry copper-ore-Lagerstätte hin. Aus den vorliegenden Untersuchungen und im Sinne der Plattentektonik ergibt sich, daß der Sar Cheshmeh-Gesteinskomplex von Magmen des Kontinentralrandes gebildet wurde. Gleiches gilt für die Andesitformation von Ardestan im zentralen Iran. Die Wurzel der Magmenherde liegt wahrscheinlich in einer Tiefe von ca. 140 bis 160 km, was in etwa der Tiefenlage der Benioff-Zone entspricht.
The copper ore deposit of Sar Cheshmeh in South Iran is situated in a volcanic zone which runs 150 kms north parallel to the Zagros overthrust. The orebody lies within a latitandesite-rhyodazite complex. The mineral zoning and the hydrothermal alteration of the rocks indicate a porphyry copper ore deposit. According to the plate tectonic theory the Sar Cheshmeh rock complex is formed by rocks of the continental margin type. The same applies to the andesite formation of Ardestan in Central Iran. The magmas orginated probably at a depth of 140–160 kms, this being also the depth of the Benioff zone.
Résumé Le gisement métallifère de cuivre de Sar Cheshmeh en Iran du Sud est situé dans une zone volcanique parallèle au charriage du Zagros, à 150 km au nord. Il se trouve dans un complexe de latiteandésite-rhyodacite. La zone minéralisée et l'altération hydrothermale des roches indiquent un gisement de minerai de cuivre porphyrique. Selon la théorie des plaques, le complexe des roches de Sar Cheshmeh est formé de roches du type marge continentale. Cela vaut aussi pour la formation andésitique d'Ardestan en Iran central. Le magma provient probablement d'une profondeur de 140 à 160 km, ce qui corresponde à peu près à la Zone de Bénioff.
— Sar Cheshmeh — , 150 . - . , porphyry copper-ore, . . - . — —, Sar Cheshmeh . , . , , 140 160 , .相似文献
42.
Hassan Mohamed Hakim Saibi Mohand Bersi Sami Abdelnabi Baher Geith Hamdy Ismaeil Thomas Tindell Hideki Mizunaga 《Arabian Journal of Geosciences》2018,11(21):674
The Um Salatit is a gold occurrence situated in the Central Eastern Desert of Egypt. The studied area is characterized by an intensive imbrication zone of serpentinites and metavolcanic rocks. The integrated use of aeromagnetic and spectral reflectance remote sensing data has proved effective for mapping geology related to ore deposits. Spectral reflectance maps have been produced to discriminate various rocks, such as serpentinites, gabbros, and metavolcanic rocks. 3-D inversion of aeromagnetic data acquired over the Um Salatit study area produced a 3-D magnetic susceptibility model showing magnetic bodies surrounded by less magnetic host rock. The magnetic features are elongated ENE-WSW parallel to the major thrust fault and mapped the Um Salatit serpentinized rocks. Remote sensing data allow investigating surficial geological features and mapping the mineralized areas. Remote results, in conjunction with 3-D inversion of aeromagnetic data, demonstrate that gold occurrence in the study area was effectively restricted to the highly magnetic zone interpreted as host rocks. 相似文献
43.
Mehani Youcef Benouar Djilali Bechtoula Hakim Kibboua Abderrahmane 《Natural Hazards》2011,59(1):529-551
Algeria is a country with a high seismic activity. During the last decade, many destructive earthquakes occurred, particularly
in the northern part, causing enormous losses in human lives, buildings, and equipments. In order to reduce this risk in the
capital and avoid serious damages to the strategic existing buildings, the government decided to invest in seismic upgrade,
strengthening, and retrofitting of these buildings. To do so, seismic vulnerability study of this category of buildings has
been considered. Structural analysis is performed based on a site investigation (inspection of the building, collecting data,
materials characteristics, general conditions of the building, etc.) and existing drawings (architectural plans, structural
design, etc.). The aim of these seismic vulnerability studies is to develop guidelines and a methodology for rehabilitation
of existing buildings. This paper presents the methodology followed in our study and summarizes the vulnerability assessment
and strengthening of one of the strategic buildings according to the new Algerian Seismic Design Code RPA 99/version 2003.
As a direct application of this methodology, both static equivalent method and nonlinear dynamic analysis are performed and
presented in this paper. 相似文献
44.
Hakim Gabtni Badia Chulli Zenatti Chokri Jallouli Kevin L. Mickus Mourad Bedir 《Arabian Journal of Geosciences》2011,4(3-4):507-516
An analysis of Bouguer gravity anomaly data and geothermal gradient data obtained from bottom hole and drill stem tests temperature is used to determine the crustal structure of the Sahel Basin in eastern Tunisia and its role in the maturation and location of the large number of oil and gas fields in the region. The regional Bouguer gravity anomaly field is dominated by gradual increase in values from the northwest to southeast and is may be caused by crustal thinning as revealed by regional seismic studies. In addition, higher geothermal gradients in the same region as the Bouguer gravity anomaly maximum add an additional constraint for the existence of crustal thinning in the region. A detailed analysis of the Bouguer gravity anomaly data was performed by both upward continuation and horizontal gradients. These two techniques were combined to show that the study area consists of two structural regions: (1) the North–South Axis (NOSA)–Zeramedine region which is characterized by northwest-dipping, northeast-striking faults, thicker crust (30–31 km) and low geothermal gradients, and (2) the Mahres–Kerkennah region which is characterized by vertical, northwest-striking faults, thinner crust (28–29 km) and higher geothermal gradients. The correlation of a variety of features includes mapped and geophysically defined faults, volcanic rocks, a thinned crust and high geothermal gradients within the same location as known oil and gas fields indicate that the faults are a major factor in the location of these petroleum accumulations. 相似文献
45.
Hakim Saibi 《Computational Geosciences》2011,15(4):709-719
The Obama geothermal field is one of the most interesting geothermal areas in Kyushu Island, Southwestern Japan, because of
its large number of high-temperature springs. A 3D numerical simulation study using the simulator TOUGH2 (module EOS3) was
carried out to obtain a comprehensive hydrothermal model of the field. From previous geochemical studies, two main fluid sources
were suggested for the Obama geothermal system: cold (sea, surface, and ground) water and deep geothermal fluids. We propose
two heat sources, a lateral one at the eastern boundary of the system, near the West Unzen High Temperature Body located west
of the Unzen fumarolic field, and a second one beneath the Obama geothermal field. The first source contributes the system
by 150°C fluids. The second source contributes by 100°C fluids. Our model indicates that the first source has a temperature
of 150°C, which agrees with the results from previous geochemical studies. The low enthalpy of the second source could be
explained by the mixing of geothermal fluids with seawater, as the area is near the seashore and is highly faulted. The model
that was developed can explain many of the subsurface processes active in the Obama geothermal field. 相似文献
46.
Ayadi Rahma Trabelsi Rim Zouari Kamel Saibi Hakim Itoi Ryuichi Khanfir Hafedh 《Hydrogeology Journal》2018,26(4):983-1007
Major element concentrations and stable (δ18O and δ2H) and radiogenic (3H and 14C) isotopes in groundwater have proved useful tracers for understanding the geochemical processes that control groundwater mineralization and for identifying recharge sources in the semi-arid region of Sfax (southeastern Tunisia). Major-ion chemical data indicate that the origins of the salinity in the groundwater are the water–rock interactions, mainly the dissolution of evaporitic minerals, as well as the cation exchange with clay minerals. The δ18O and δ2H relationships suggest variations in groundwater recharge mechanisms. Strong evaporation during recharge with limited rapid water infiltration is evident in the groundwater of the intermediate aquifer. The mixing with old groundwater in some areas explains the low stable isotope values of some groundwater samples. Groundwaters from the intermediate aquifer are classified into two main water types: Ca-Na-SO4 and Ca-Na-Cl-SO4. The high nitrate concentrations suggest an anthropogenic source of nitrogen contamination caused by intensive agricultural activities in the area. The stable isotopic signatures reveal three water groups: non-evaporated waters that indicate recharge by recent infiltrated water; evaporated waters that are characterized by relatively enriched δ18O and δ2H contents; and mixed groundwater (old/recent) or ancient groundwater, characterized by their depleted isotopic composition. Tritium data support the existence of recent limited recharge; however, other low tritium values are indicative of pre-nuclear recharge and/or mixing between pre-nuclear and contemporaneous recharge. The carbon-14 activities indicate that the groundwaters were mostly recharged under different climatic conditions during the cooler periods of the late Pleistocene and Holocene.
相似文献47.
48.
Climate Dynamics - Coupled atmosphere–ocean data assimilation (DA) experiments are performed for estimating the Atlantic meridional overturning circulation (AMOC). Recovery of the AMOC with... 相似文献
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50.
Christophe Grenier Damien Régnier Emmanuel Mouche Hakim Benabderrahmane François Costard Philippe Davy 《Hydrogeology Journal》2013,21(1):257-270
The impact of glaciation cycles on groundwater flow was studied within the framework of nuclear waste storage in underground geological formations. The eastern section of the Paris Basin (a layered aquifer with impervious/pervious alternations) in France was considered for the last 120 ka. Cold periods corresponded with arid climates. The issue of talik development below water bodies was addressed. These unfrozen zones can maintain open pathways for aquifer recharge. Transient thermal evolution was simulated on a small-scale generic unit of the landscape including a “river” and “plain”. Coupled thermo-hydraulic modeling and simplified conductive heat transfer were considered for a broad range of scenarios. The results showed that when considering the current limited river dimensions and purely conductive heat transfer, taliks are expected to close within a few centuries. However, including coupled advection for flows from the river to the plain (probably pertinent for the eastern Paris Basin aquifer recharge zones) strongly delays talik closure (millennium scale). The impact on regional underground flows is expected to vary from a complete stop of recharge to a reduced recharge, corresponding to the talik zones. Consequences for future modeling approaches of the Paris Basin are discussed. 相似文献