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991.
文章通过对平果铝厂厂区工程地质勘察资料的研究 ,系统地分析、总结了该厂厂区岩溶地基特征及其处理方法 ,可供其他岩溶地区类似条件的工程项目提供指导和借鉴。  相似文献   
992.
Turbulence is defined as an eddy-like state of fluid motion where the inertial-vortex forces of the eddies are larger than any of the other forces that tend to damp the eddies out. Energy cascades of irrotational flows from large scales to small are non-turbulent, even if they supply energy to turbulence. Turbulent flows are rotational and cascade from small scales to large, with feedback. Viscous forces limit the smallest turbulent eddy size to the Kolmogorov scale. In stratified fluids, buoyancy forces limit large vertical overturns to the Ozmidov scale and convert the largest turbulent eddies into a unique class of saturated, non-propagating, internal waves, termed fossil-vorticity-turbulence. These waves have the same energy but different properties and spectral forms than the original turbulence patch. The Gibson (1980, 1986) theory of fossil turbulence applies universal similarity theories of turbulence and turbulent mixing to the vertical evolution of an isolated patch of turbulence in a stratified fluid as its growth is constrained and fossilized by buoyancy forces. Quantitative hydrodynamic-phase-diagrams (HPDs) from the theory are used to classify microstructure patches according to their hydrodynamic states. When analyzed in HPD space, previously published oceanic datasets showed their dominant microstructure patches are fossilized at large scales in all layers. Laboratory and field measurements suggested phytoplankton species with different swimming abilities adjust their growth strategies by pattern recognition of tur-bulence-fossil-turbulence dissipation and persistence times that predict survival-relevant surface layer sea changes. New data collected near a Honolulu waste-water outfall showed the small-to-large evolution of oceanic turbulence microstructure from active to fossil states, and revealed the ability of fossil-density-turbulence patches to absorb, and vertically radiate, internal wave energy, information, and enhanced turbulent-mixing-rates toward the sea surface so that the submerged waste-field could be detected from a space satellite (Bondur and Filatov, 2003).  相似文献   
993.
三峡数字地震台网中心记录典型波形初步分析   总被引:10,自引:6,他引:4  
对三峡地区数字地震台网中心记录的典型的天然地震、疑炮、一次爆破及一次滑坡等波形进行初步分析后认为:①数字地震仪器与模拟地震仪器所记录的地震波形特征基本一致;②三峡地区数字地震台网中心2003年5月19日至2004年1月所记录的多数天然地震事件是非构造型(由溶洞塌陷引起的陷落型)地震事件。  相似文献   
994.
三峡库区巴东马鬃山地振动观测与成因讨论   总被引:8,自引:7,他引:1  
在长江三峡巴东库段马鬃山村开展地振动现场仪器监测和宏观调查的基础上,着重对其形成条件及成因机理进行了分析。初步认为,该村近半年来持续发生的地振动、地声及民宅破坏等地质灾害,部分来自近邻构造地震的影响,而大多数是溶洞塌陷引发的非构造地震。  相似文献   
995.
文章从岩溶发育、土层存在和地下水活动 3个方面论述自然因素、抽水因素在岩溶塌陷的形成过程中所起的作用 ,认为自然因素是决定岩溶塌陷的因素 ,抽水因素是加速岩溶塌陷的因素  相似文献   
996.
作为地壳形变监测的一种手段,地应变观测可监测微尺度下的地表应变变化,其分辨率一般为10-9。目前地震地球物理观测台网在网运行的洞体应变观测台站有111个,分量钻孔应变观测站59个,钻孔体应变测站有68个,产出数据包括原始观测数据、台站预处理数据和产品数据,可为地震研究、地球动力学研究提供重要的数据支撑。  相似文献   
997.
The Cueva del Silo is part of the lower karst level of the Cueva Mayor-Cueva del Silo karst system (Sierra de Atapuerca, Burgos, Spain), whose evolution has preserved an impressive archeo-paleoanthropological sequence since the Early Pleistocene. Cueva del Silo is remarkable for the presence of fluvial deposits that record the entry of the Arlanzón River water in the cave system, providing a key sequence to investigate the fluvio-karstic relationships that give rise to this endokarst system. In order to provide a chronological framework to these fluvial deposits, six sediment samples were dated by Electron Spin Resonance and 16 samples by paleomagnetism, collected from two outcrops: Galería de las Arenas and Sala del Caos. Our results provide maximum mean age of around 1600 ka and a minimum age of 916 ± 136 ka for the deposits in Sala del Caos. The younger date from Sala del Caos might represent the last fluvial input from Arlanzón River in the lower karst level. In contrast, ESR ages estimates of 1268 ± 133 ka and 1262 ± 108 ka were obtained for Galería de las Arenas sequence, which could indicate re-sedimentation processes from the intermediate karst level where similar ages were published. The annual dose might be wrongly assessed due to the re-sedimentation processes inside the karst, hence, ESR ages for these facies should be treated with extreme caution.  相似文献   
998.
China has been the leading country worldwide in direct geothermal utilization for a rather long time, which has contributed significantly to reducing carbon emissions. But the installed capacity of geothermal power generation in China is very small, and there are only a few geothermal power plants in China, specifically in Tibet, including the well-known Yangbajing geothermal power plant. Therefore, it is anticipated that more high-temperature geothermal resources will be discovered in order to promote China’s power generation. There is potential for high-enthalpy geothermal in the Eastern Linqing Depression in Shandong Province, where geothermal energy is stored in Ordovician and Cambrian carbonate strata. Based on the geothermal gradient in Cenozoic strata and the depth of the target geothermal reservoir, the temperature distribution pattern of the reservoir was analyzed, and two “sweet points” were identified in the Yucheng geothermal field and the Guanxian geothermal field, where the reservoir temperature is predicted to be higher than 200°C at a depth of less than 8000 m. Due to the low karst fissure ratio and the insufficient geothermal fluid in the geothermal reservoir, it is recommended that an enhanced geothermal system be set up, to increase the permeability of the natural fracture system in the carbonate formations and provide sufficient fluid for power generation through reinjection of used geothermal fluid. The power generation capacity of the two geothermal fields was estimated using a volumetric method, revealing a power generation capacity of 1621.02 MWe for the Yucheng geothermal field, and 1287.19 MWe for the Guanxian geothermal field.  相似文献   
999.
曹建华 《地球学报》2021,42(3):309-312
自第三纪以来,康滇地块的地壳运动十分活跃,形成了喀斯特断陷盆地.由于该区"盆-山"地形变化剧烈,山地气候反差大;而西南季风的控制,使得该地区旱季是雨季的2倍,水资源的时空分配不均,土壤流/漏失严重,植被立地条件差,以至于石漠化问题缓解不明显.2016—2020年,在该区实施了国家重点研发计划典型脆弱生态修复与保护专项项目"喀斯特断陷盆地石漠化演变及综合治理技术与示范",为我们了解喀斯特断陷盆地关键带与生态地质特征、总结已实施石漠化综合治理工程成果提供了条件.在《地球学报》编辑部的大力支持下,从4个方面"水资源、水土流失、生态地质、生态服务",15篇文章构成"喀斯特断陷盆地关键带与生态地质"专辑,专辑并没有包括专项项目的全部内容,但对深入了解喀斯特断陷盆地的地质、气候、水文、生态和生态服务功能提供重要的参考价值.  相似文献   
1000.
塔里木盆地塔河油田TH12402井区位于志留系覆盖区,发育典型的古岩溶缝洞型储集层,是塔河油田西北部奥陶系主要的产建阵地之一。基于三维地震数据、测井和钻井资料,并结合地震属性提取技术,对该区下奥陶统岩溶发育条件和储集层发育特征进行了研究,探讨了岩溶洞穴的控制因素和发育模式。结果表明: TH12402井区处于北西向次级鼻状构造的南翼,该区发育加里东中期Ⅲ幕古岩溶作用,岩溶地形以低幅度的溶丘和洼地为主,地表水系呈南北向汇流且分支水系相对欠发育;岩溶储集空间以大型迷宫状岩溶管道和分散的孤立状洞穴为主,主要分布在不整合面以下40~100m,且以未充填为主;近东西向的走向断层、次级鼻状构造以及上奥陶统地层尖灭线联合控制了古岩溶洞穴的发育,形成了平缓岩溶地貌区走向断裂汇流型岩溶洞穴模式。上述成果为相似井区的古岩溶储集层预测和井位部署提供了理论依据。  相似文献   
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