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1.
Using the database of automatic hydrometeorological stations, installed in the Don RIver delta and Taganrog Bay seashore, the sources of the anomalois scale water negative surge and salinization of the Azov Sea under conditions of low river flow in 2015–2016 are studied. The new schemes of stratification and advection of salty sea waters in the Don River mouth under different weather conditions, water discharge and levels are given.  相似文献   

2.
多年冻土融沉性分类研究   总被引:2,自引:2,他引:0  
在冻土工程中,冻土的融沉性评价是工程地质勘察的主要内容之一,融沉性分类是冻土地基基础设计施工的重要依据.根据345个冻土原状样品融沉压缩试验数据,提出了细砾、砂土、粉土、黏性土、泥炭化黏性土和泥炭质土等6类土的融沉系数一含水量或融沉系数一超塑含水量线性回归方程式,得到与各融沉性分级相应的界限含水量或界限超塑含水量.最后...  相似文献   

3.
考虑核电厂地基-基础的动力相互作用,应用显式动力有限差分法分析了地震作用下极软岩、较软岩、坚硬岩上核电厂建筑结构基础的地震响应特征,比较了岩石坚硬程度对基础加速度反应谱的影响。研究表明:随着岩石坚硬程度的提高,核电厂建筑物结构基础的地震响应有增加的趋势;在周期轴上,基础处的加速度反应谱曲线会随着岩石坚硬程度的提高逐渐向短周期(高频段)方向移动。在高频段,建造于较坚硬岩石上基础结构的加速度反应谱值偏大;在中等频段,建造于较软岩石上基础结构的加速度反应谱值偏大;在低频段,岩石坚硬程度对加速度反应谱的影响不显著。  相似文献   

4.
《International Geology Review》2012,54(10):1218-1225
Copper deposits of Cuba belong to the Jurassic lead-zinc-copper, Cretaceous copper and Paleogene copper complexes, which differ substantially in their formation conditions. The island is differentiated into a number of metallogenic zones formed at the initial and early stages of the Cuba folded province. Pinar del Rio, Pinos, Trinidad and Oriente zones, of an intrageanticlinal nature, are prospective with respect to copper vein deposits of the lead-Zinc-copper complex. The Sasa and Cauto zones - intrageosynclinal - are prospective with regard to copper-pyrite and copper vein deposits of the Cretaceous complex. A metallogenic study of the island is indicated in planning the exploration of its copper prospects. -- AGI Staff.  相似文献   

5.
This work presents the results of a study of the biogeographical distribution of Late Albian-Maastrichtian ammonites, found in sequences of the Pacific coast of Russia. The taxa typical of the Pacific Realm were identified, and their distribution traced beyond the borders of this region. In addition, species-migrants, distributed within the studied area were established. As a results of our works, a high level of endemism of ammonite fauna of the East of Russia was noted (75–88% of endemic species, on average). The bipolarity, previously established in the distribution of ammonoids within the Pacific Paleobiogeographical Realm, as well as their high regional provincialism, was confirmed. The following division of the studied area into faunal ammonite provinces in the Late Cretaceous was proposed: Arctic Province; Boreal-Pacific Province, including northeastern Russia (Chukotka Peninsula, the Koryak Upland, Penzhyna Gulf) and the boreal coast of North America (Alaska Peninsula, Arctic Canada and British Columbia); Northwest Pacific Province, including the Primorye Territory, Sakhalin and Shikotan Islands, the Japanese Islands; Northeast Province of the Pacific (the western coast of the United States and Mexico); Southwest Pacific (Australia, New Zealand, Oceania) and Southeast (the western coast of South America and Antarctica, Seymour and James Ross Islands) Provinces. This division is confirmed by data on inoceramid species. In addition, levels of global transgressions and general sea level rise, associated with the appearances of most of widespread marine taxa in the Pacific shelf seas, are established. These include Late Albian, Cenomanian-Turonian boundary, Late Coniacian, Late Campanian, Early-Late Maastrichtian boundary. Moreover, migration of ammonites occurred due to the Tethys Ocean extension and followed the northern sea straits in the Arctic Ocean and within the Pacific Realm, depending on warm currents. Both the counter and one-way migrations were established.  相似文献   

6.
含水层渗透性空间分布的指示克立格估值   总被引:3,自引:0,他引:3  
宋刚  万力  胡伏生  高茂生  张琦伟 《地学前缘》2005,12(Z1):146-151
详细介绍了指示克立格估值计算的理论和方法。以指示变异函数为基本工具分析了华北某地区第四系含水层渗透性空间分布的结构特征,结果表明该地区含水层渗透性存在明显的各向异性特征。水平方向上,X轴方向的相关性较Y轴方向的好,Z轴的相关性最差。用指示克立格法对未采样点处进行估值,估值结果显示含水层渗透性由山前向滨海逐渐变低,在垂直方向上,渗透性变化不明显,浅部比深部略好;同时给出了估计精度,并认为对估计精度不高的区域可通过增加适当的工程加以控制。最后用交叉验证法对估值结果进行了检验,证明建立的指示变异函数模型合理且估值效果较好。这一实际应用表明指示克立格法可以很好地描述第四系含水层渗透性的空间分布规律。  相似文献   

7.
A review of theories of mechanisms of induced seismicity   总被引:1,自引:0,他引:1  
Theories of the physical processes leading to the stimulation of seismic activity by underground explosions, fluid injection, and reservoir impoundment are summarized. In all cases, the materials must be pre-stressed to a substantial fraction of their breaking strength in order for seismicity to be induced. Stress concentrations due to the presence of old faults or to inhomogeneities in the material properties play an important role in localizing induced seismicity.

For the few cases for which data are available, the stimulation of earthquakes by fluid injection in bore holes is adequately explained by a Coulomb-Mohr failure criterion and the concept of effective pressure in a water-filled porous mechanism. Reservoir-related earthquakes are most likely due to the same mechanism, but, in view of the low injection pressures, additional physical or chemical effects of the water on the materials may play an important role. There may be a weakening of the materials in old fault zones by the introduction of water or static fatigue in silicate rocks due to stress corrosion.  相似文献   


8.
张玉成  杨光华  姜燕  姚捷  史永胜 《岩土力学》2010,31(Z1):349-356
结合爆破数值模拟中爆破荷载的特点,分析了各种荷载施加方法的特点及爆破震动场模拟的要求,基于圣维南荷载等效原理,提出了爆破荷载的等效施加方法,即将作用在炮孔壁上的爆破荷载等效后,施加在同排炮孔中心线或者面上来模拟爆破荷载的作用。结果表明,等效施加方法在近区存在一定差异,但在中远区吻合得较好。利用该等效荷载施加方法,采用三维实体模型计算分析了某沉管隧道基槽爆破施工对既有堤岸稳定性影响,计算了周围不同位置、不同深度位置处的振动响应,并在此基础上,分析研究了减小爆破振动对既有结构物影响的减振措施,可为类似工程提供借鉴。  相似文献   

9.
过去,人们对岩(矿)石磁参数测定工作不够重视,多数磁测工作是按照相应的工作规范只是测一测岩(矿)石磁参数.甚至有不少磁测工作不对工区内的岩(矿)石标本做磁参数测定工作,或只做少量的测定工作.而这些为数不多的磁参数测定工作也只是作磁化率和剩余磁化强度的平均数(众数)统计,没有对标本磁参数离散程度进行深入的统计研究.尽管利用变异系数表征磁参数的相对离散程度是很早就被人们认识到的.但是,目前就是在极少数关注磁参数离散程度的研究者中,也多引用标准离差,而不是变异系数.笔者对岩(矿)石标本磁参数的变异系数作了浅显的研究,并认为研究岩石磁性强度的自身不均匀性和相互之间的不均匀性对比,变异系数应当是一个不错的参数.  相似文献   

10.
《International Geology Review》2012,54(12):1428-1439
The author suggests a hypothesis of multistage evolution of the mobile crust zones of the Earth, taking into consideration the type of crustal columnar section (oceanic, intermediate, continental, and orogenic), the history of tectonic and magmatic epochs (Caledonian, Hercynian, Kimmeridgian, and Alpine), and the factor of lineament type mobile zones existing during long periods of geological history and contributing to the activation of magmaticprocesses. --E.A. Alexandrov.  相似文献   

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