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91.
Ayşen Davraz M. Tahir Nalbantçılar Simge Varol İsmail Önden 《Chemie der Erde / Geochemistry》2022,82(2):125867
A conceptual model with water samples from ten geothermal fields (?smil, Ilg?n (Çavu?cugöl), Tuzlukçu-Ak?ehir, Seydi?ehir and Kavakköy, Hüyük, Ere?li-Akhüyük, Kad?nhan?, Cihanbeyli, Karap?nar and Bey?ehir) in the province of Konya defined the geothermal system. Carbonates, quartzite and marbles of Paleozoic metamorphics are the reservoir rocks and the heating sources are igneous rock intrusions and geothermal gradient. The variable thermal water (CaMgHCO3, CaSO4, NaSO4, CaHCO3, CaNaHCO3, NaCl and CaNaClHCO3) had EC and temperature between 177.8 and 56,100 μS/cm and between 18.3 and 44 °C, respectively. Ca2+ in geothermal fluids are associated with marble and carbonate rocks and the high chloride shows direct connection with deep geothermal system, and prolonged contact with evaporite rocks. Sulphate originates from dissolution of and oxidation of sulphate and sulphur-bearing minerals. The high As, B, F and Mn concentration in some thermal water samples were determined as 85 μg/l, 148.56 mg/l, 3.01 mg/l and 208.13 mg/l, respectively. Reservoir temperatures computed by Na/K geothermometers were between 85.37–158.89 °C for Ak?ehir thermal waters and 58.78–90.45 °C for Ere?li thermal waters. The maximum reservoir temperature of other geothermal waters was 75 °C by the silica geothermometers. 相似文献
92.
Lan Chen Chen Jing an Zeng Yan Guo Jianyang Zhang Runyu Wang Jingfu Yang Haiquan Ji Yongxue 《地球科学进展》2015,30(10):1172-1181
Deep lakes always maintain vertical thermal stratification due to their physical structure. The thermocline prevents the transfer of oxygen from epilimnion to hypolimnion, leading to the formation of anoxic conditions in deeper water, the enhanced release of endogenous pollutants and the deterioration of water quality. Oxygenation is an effective measure to improve the water quality of deep lakes and mitigate the release of endogenous pollutants via the increase of the oxygen level in water. This paper provided an overview of the method and theory of oxygenation in deep lakes. Advantages and limitations of different methods of oxygenation, including artificial destratification, airlift aerators, Speece cone and bubble plume diffusers, were discussed. In addition, challenges and prospects of oxygenation were assessed based on the analyzing of typical examples of oxygenation in deep lakes and the difference in oxygenation system used in deep lakes and shallow lakes. 相似文献
93.
针对现有侵蚀学坡长串行算法在处理大区域海量数据时计算能力的不足,基于消息传递接口(MPI)并行化工具,提出了一种格网DEM的侵蚀学坡长并行计算方法,采用缓冲区更新计算策略,解决了并行计算过程中的数据依赖性问题。选取陕北黄土高原的两组不同分辨率的DEM数据对并行算法进行了测试,结果表明,提出的并行计算方法可以有效降低侵蚀学坡长的计算时间,并取得了较好的并行效率。 相似文献
94.
水汽层析代数重构算法 总被引:1,自引:0,他引:1
讨论了代数重构算法在水汽层析应用中的各种问题,包括约束条件的构造、层析初值的选择、松弛因子的计算、终止条件的确定等,给出了计算最优松弛因子的黄金分割搜索法和确定终止条件的NCP规则,对比分析了Kaczmarz、Randkaczmarz、Symkaczmarz、SART、Landweber、Cimmino、CAV、DROP等8种常见的代数重构算法,并以香港SatRef的观测数据进行了试验。试验结果表明,以上8种代数重构技术都能够满足水汽层析的要求;迭代终止条件比松弛因子更为重要;采用文中计算最优松弛因子的黄金分割搜索法和NCP迭代终止条件,CAV算法结果最优,其次为Cimmino算法。 相似文献
95.
喀拉萨依岩体位于东准噶尔卡拉麦里碱性花岗岩带西端,由钾长花岗岩和二长花岗岩组成。LA-ICP-MS锆石U-Pb年龄为307.7±3.2Ma~309.6±2.0Ma,岩石高硅(Si O2平均含量为77.25%)、富碱(K2O+Na2O=7.50%~9.23%)、低铝(A/CNK=0.922~1.084),贫钙、镁;富集Rb、K、Th等大离子亲石元素及Zr、Hf等高场强元素和稀土元素,亏损Ba、Sr、Eu。10000Ga/Al值变化于7.00~10.35之间,总体上具碱性A型花岗岩的特征,是该岩带东侧老鸦泉—黄羊山A型花岗岩岩基经高程度分异演化的产物,并非前人认为的S型花岗岩。岩体具正εNd(t)值(3.5~6.0)和年轻的Nd模式年龄(TDM2=520~630Ma),Pb同位素投点位于造山带演化线附近,同位素数据显示岩浆来源于新生造山带下部的年轻地壳。从本次1∶5万区调成果看,卡拉麦里洋盆在晚泥盆世之前已经闭合,从晚泥盆世开始转入碰撞后的拉张环境,在晚石炭世早期进入板内裂谷发展阶段,因此喀拉萨依岩体应是该区板内裂谷阶段而非前人所说的后碰撞阶段的产物。 相似文献
96.
97.
Integrated Indicators-based Gradation of Cultivated Land Quality in Mountainous Region of Southwestern China 总被引:1,自引:0,他引:1
SHAO Jing'an WEI Chaofu XIE Deti ZHOU Yan 《山地科学学报》2006,3(3):259-270
1 Introduction The gradation of cultivated land is to assess the suitability of cultivated land for agricultural production in terms of natural and economic prop-erties of land (Feng et al. 2004). It can be used to evaluate sustainability of land use and … 相似文献
98.
99.
Erkan Gökaşan Cem Gazioğlu Bedri Alpar Zeki Yücel Şükrü Ersoy Oğuz Gündoğdu Cenk Yaltırak Buser Tok 《Geo-Marine Letters》2001,21(4):183-199
Active faults aligning in NW–SE direction and forming flower structures of strike-slip faults were observed in shallow seismic data from the shelf offshore of Avc?lar in the northern Marmara Sea. By following the parallel drainage pattern and scarps, these faults were traced as NW–SE-directed lineaments in the morphology of the northern onshore sector of the Marmara Sea (eastern Thrace Peninsula). Right-lateral displacements in two watersheds of drainage and on the coast of the Marmara Sea and Black Sea are associated with these lineaments. This right-lateral displacement along the course of these faults suggests a new, active strike-slip fault zone located at the NW extension of the northern boundary fault of the Ç?narc?k Basin in the Marmara Sea. This new fault zone is interpreted as the NW extension of the northern branch of the North Anatolian Fault Zone (NAFZ), extending from the Ç?narc?k Basin of the Marmara Sea to the Black Sea coast of the Thrace Peninsula, and passing through B üy ük çekmece and K ü ç ük çekmece lagoons. These data suggest that the rupture of the 17 August 1999 earthquake in the NAFZ may have extended through Avc?lar. Indeed, Avc?lar and ?zmit, both located on the Marmara Sea coast along the rupture route, were strongly struck by the earthquake whereas the settlements between Avc?lar and ?zmit were much less affected. Therefore, this interpretation can explain the extraordinary damage in Avc?lar, based on the newly discovered rupture of the NAFZ in the Marmara Sea. However, this suggestion needs to be confirmed by further seismological studies. 相似文献
100.
Özgür Kişi 《水文研究》2009,23(14):2081-2092
This paper proposes the application of a conjunction model (neuro‐wavelet) for forecasting monthly lake levels. The neuro‐wavelet (NW) conjunction model is improved combining two methods, discrete wavelet transform and artificial neural networks. The application of the methodology is presented for the Lake Van, which is the biggest lake in Turkey, and Lake Egirdir. The accuracy of the NW model is investigated for 1‐ and 6‐month‐ahead lake level forecasting. The root mean square errors, mean absolute relative errors and determination coefficient statistics are used for evaluating the accuracy of NW models. The results of the proposed models are compared with those of the neural networks. In the 1‐month‐ahead lake level forecasting, the NW conjunction model reduced the root mean square errors and mean absolute relative errors by 87–34% and 86–31% for the Van and Egirdir lakes, respectively. In the 6‐month‐ahead lake level forecasting, the NW conjunction model reduced the root mean square errors and mean absolute relative errors by 34–48% and 30‐46% for the Van and Egirdir lakes, respectively. The comparison results indicate that the suggested model could significantly increase the short‐ and long‐term forecast accuracy. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献