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51.
Sabah A. Ismail Sarmad A. Ali Allen P. Nutman Vickie C. Bennett Brain G. Jones 《地学前缘(英文版)》2017,8(5):1073-1087
The Pushtashan suprasubduction zone assemblage of volcanic rocks, gabbros, norites and peridotites occurs in the Zagros suture zone, Kurdistan region, northeastern Iraq. Volcanic rocks are dominant in the assemblage and consist mainly of basalt and basaltic andesite flows with interlayered red shale and limestone horizons. Earlier lavas tend to be MORB-like, whereas later lavas display island arc tholeiite to boninitic geochemical characteristics. Tholeiitic gabbros intrude the norites and display fractionation trends typical of crystallisation under low-pressure conditions, whereas the norites display calc-alkaline traits, suggesting their source included mantle metasomatised by fluids released from subducted oceanic crust. Enrichment of Rb, Ba, Sr, Th and the presence of negative Nb anomalies indicate generation in a suprasubduction zone setting. Trondhjemite and granodiorite intrusions are present in the volcanic rocks, gabbros and norites. SHRIMP U-Pb dating of magmatic zircons from a granodiorite yields a mean~(206)Pb/~(238)U age of 96.0 ±2.0 Ma(Cenomanian). The initial ε_(Hf) value for the zircons show a narrow range from +12.8 to+15.6, with a weighted mean of + 13.90±0.96. This initial value is within error of model depleted mantle at 96 Ma or slightly below that, in the field of arc rocks with minimal contamination by older continental crust. The compositional bimodality of the Pushtashan suprasubduction sequence suggests seafloor spreading during the initiation of subduction, with a lava stratigraphy from earlyerupted MORB transitioning into calc-alkaline lavas and finally by 96 Ma intrusion of granodioritic and trondhjemitic bodies with juvenile crustal isotopic signatures. The results confirm another Cretaceous arc remnant preserved as an allochthon within the Iraqi segment of the Cenozoic Zagros suture zone. Implications for the closure of Neo-Tethys are discussed. 相似文献
52.
Md. F. Hossain 《International Journal of Environmental Science and Technology》2017,14(12):2709-2720
In order to make Mars a better planet, in this paper, photo-dissociation technology, mathematical modeling, and a series of chemical reaction methodology have been proposed to create a vibrant ecosystem and balance the atmosphere on Mars. Since CO2 is a stable compound, breaking it down into C and O2 always is challenging, but exciting thought. Interestingly, my recent research revealed that photo-dissociation by utilizing UVV (laser) could be an exciting technology to split CO2 into C + O2 since the theoretical reaction suggested that the production of C + O2 channel from CO2 photo-exciting technology releases the energetic level threshold of C(3P2) + O2(X3∑ g ? ) that can be detected by ultraviolet laser pump-probe spectroscopy. Subsequently, a mathematical model for creating of ocean on Mars by breaking its substantial polar ice has been performed considering algorithms for surface and coordinate between the barotropic momentum and continuity equations, and interestingly the calculation suggested that it is very much possible to flow ocean on Mars surface to meet its water demand. Subsequently, proposed series of chemical reaction technology suggested that implementation of carbonator looping and plasma reaction paths can convert photo-dissociated carbon (C) into N2 and NH3 to enrich Mars’ soil in order to grow vegetation as well as to create a balance ecosystem in Mars eventually. Finally, sustainable green technology has been proposed for the development of Mars to be a complete balanced planet to deliver all basic and modern needs to run daily life smoothly. Thus, implication of chemical reaction technologies along with sustainable development plans can indeed make the Mars a vibrant environment to live there in clean and green. 相似文献
53.
Hany S. Mesbah Ahmed Ismail Ayman I. Taha Usama Massoud Mamdouh M. Soilman 《Arabian Journal of Geosciences》2017,10(10):230
Water seepage to ground surface at a limestone quarry located at Wadi Garawy about 20 km south-east of Helwan city in Egypt posed a real threat to the mining activity at the quarry. The quarry area is known to be very dry for decades and away from water utilities and infrastructures that may cause water leaks to the quarry. Geophysical investigation including 1D Vertical Electrical Sounding (VES), 2D Electrical Resistivity Tomography (ERT) and 1D Transient Electromagnetic (TEM) surveys were conducted to characterize the rock sequence and locate what could be a possible source of water seepage to the quarry. The resistivity profiles generated from the VES and TEM surveys mapped the rock units in the area down to depths exceeded 100 m. The ERT profiles acquired from the quarrying zone close to the water seepage spot have imaged the top of groundwater level at few meters below the ground surface at the quarry open pit. The spot of groundwater seepage seemed to occur at an area of limestone dissolution that were filled by finer sediments. The finer sediments acted as a hydrological conduit that allowed an upward seepage of groundwater to ground surface under the capillary action effect. 相似文献
54.
X-ray diffractometer analysis and SEM investigation confirmed the occurrence of jarosite and alunogen minerals in the Quaternary siliciclastic sabkha sediments of northern Kuwait within the Bahrah oilfield area, Arabian Gulf. Jarosite is relatively abundant in a near-surface whitish sticky tidal muddy sand layer about 60 cm thick that overlies the ferruginous sandstone of the Oligo-Miocene Ghar Formation. Jarosite occurs as clusters of euhedral pseudo-cubes of about 1 μm in size and as agglomerated nanoglobules of 250 nm in size. A hypogenetic origin related to the reaction of sulfuric acid produced by the oxidation of H2S associated with hydrocarbon gas seepages with K and Fe leachates is suggested. The restricted occurrence of jarosite within near-surface sabkha sediments may be attributed to limited tidal inundation and prevalence of arid climatic conditions. 相似文献
55.
Maroua El Ouaer Amjad Kallel Mariam Kasmi Abdennaceur Hassen Ismail Trabelsi 《Arabian Journal of Geosciences》2017,10(20):457
The potential of the autoclaved Tunisian landfill leachate treatment using microalgae (Chlorella sp.) cultivation was investigated in this study. Landfill leachate was collected from Borj Chakir landfill, Tunisia. A full factorial experimental design 22 was proposed to study the effects of the incubation time and leachate ratio factors on the organic matter removal expressed in chemical oxygen demand (COD) and ammoniacal nitrogen (NH4─N) and on the biological response of Chlorella sp. expressed by the cell density and chlorophyll content. All experiments were batch runs at ambient temperature (25 ± 2 °C). The Chlorella sp. biomass and chlorophyll a concentrations of 1.2 and 5.32 mg L?1, respectively, were obtained with 10% leachate spike ratio. The obtained results showed that up to 90% of the ammoniacal nitrogen in landfill leachate was removed in 10% leachate ratio spiked medium with a residual concentration of 40 mg L?1. The maximum COD removal rate reached 60% within 13 days of incubation time indicating that microalgae consortium was quite effective for treating landfill leachate organic contaminants. Furthermore, with the 10% leachate ratio spiked medium, the maximum lipid productivity was 4.74 mg L?1 d?1. The present study provides valuable information for potential adaptation of microalgae culture and its contribution for the treatment of Tunisian landfill leachate. 相似文献
56.
Mohammed Ismail 《地震工程与结构动力学》2015,44(7):1115-1137
The ability of a recently proposed seismic isolation system, with inherent self‐stopping mechanism, to mitigate or even eliminate seismic pounding of adjacent structures is investigated under severe near‐fault earthquakes. The isolation system is referred to as roll‐in‐cage (RNC) isolator. It is a rolling‐based isolator that provides in one unit the necessary functions of vertical rigid support, horizontal flexibility with enhanced stability, hysteretic energy dissipation, and resistance to minor vibration loads. In addition, the RNC isolator is distinguished by a self‐stopping (buffer) mechanism to limit the bearing displacement under excitations stronger than a design earthquake or at limited seismic gaps, and a linear gravity‐based self‐recentering mechanism to prevent permanent bearing displacement without causing vertical fluctuation of the isolated structure. A previously developed multifeature SAP2000 model of the RNC isolator is improved in this paper to account for the inherent buffer mechanism's damping. Then, the effectiveness of the isolator's buffer mechanism in limiting peak bearing displacements is studied together with its possibly arising negative influence on the isolation efficiency. After that, the study investigates how to alleviate or even eliminate those possibly arising drawbacks, due to the developed RNC isolator's inner pounding as a result of its buffer activation, to achieve efficient seismic isolation with no direct structure‐to‐structure pounding, considering limited seismic gaps with adjacent structures and near‐fault earthquakes. The results show that the RNC isolator could be an efficient solution for aseismic design in near‐fault zones considering limited seismic gaps. Earthquake Engineering and Structural Dynamics. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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59.
Iqbal Zafar Shahid Shamsuddin Ahmed Kamal Wang Xiaojun Ismail Tarmizi Gabriel Hamza Farooq 《Theoretical and Applied Climatology》2022,148(3-4):1429-1446
Theoretical and Applied Climatology - Satellite-based precipitation (SBP) is emerging as a reliable source for high-resolution rainfall estimates over the globe. However, uncertainty in SBP is... 相似文献
60.
Hamid Sarkheil Hossain Hassani Firuz Alinia Aliasghar Enayati Abbasali Nikandish 《Arabian Journal of Geosciences》2012,5(4):579-586
High gas production from the Dashtak formation of Tabnak hydrocarbon field in Fars province, Iran, indicates the presence of natural fractured reservoir whose production potential is dominated by the structural fracture. The connectivity of fractured media depends upon the power?Claw exponent and the fracture density. Fracture pattern traces obtained from the outcrops of producing formations of six different stations in Tabnak hydrocarbon field. 2D fracture network maps of Tabnak hydrocarbon field have been analyzed from their scaling properties. The fractal analysis of fracture intensity showed heterogeneous multi-fractal structure characterized by generalized dimensions. Distribution of fracture lengths exhibits power?Claw behavior with specific exponent. Scaling laws serve to make extrapolations and to study the fracture connectivity related to scale. Fracture distribution model and reservoir productivity can be estimated, which are of great interest in decision making to optimize gas production. 相似文献