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281.
The 26 November 2005 Jiujiang-Ruichang, Jiangxi, Ms?5.7 earthquake occurred in a seismotectonic setting of moderate earthquake. The northwest-trending Xiangfan-Guangji fault (XFG) does not enter into the epicenter vicinity, but the northeast-trending Ruichang-Wuning fault (RWF) as a regional fault extends to the epicenter nearby, appearing as the Ruichang basin and its marginal faults. Tilting of the Ruichang Basin (RCB) in the Quaternary was controlled by the RCB southeast-marginal, buried fault (RSMBF). Shallow geophysical survey reveals that the RSMBF caused an offset of the reflection layers. Drill hole columnar section demonstrates that there are about 10–12?m displacement in the lower section of the middle-Pleistocene Series along the RSMBF, but no disruption is found in the upper section of the middle-Pleistocene Series. The RSMBF not only has activity in the Quaternary, but also coincides with the nodal plane I from the focal mechanism of the Jiujiang-Ruichang Ms?5.7 earthquake. This evidence, including aftershock distribution and isoseismic lines, strongly suggests that the RSMBF might be the seismogenic tectonics. The RWF is discontinuous at the surface, and consists of three en echelon Quaternary basins, which are the Ruichang, Fanzhen and Wuning basins. Three moderate earthquakes, the Fanzhen ML?4.9 earthquake, the Yejiapu ML?4.1 earthquake and the Jiujiang-Ruichang Ms?5.7 earthquake, have happened in the basins since 1995. The seismogenic tectonics of the Jiujiang-Ruichang Ms?5.7 earthquake is not isolated, but may be controlled by the RWF at depth, the slip of which causes the accumulation of energy for earthquake occurrence.  相似文献   
282.
The basal dinocephalian clade Stenocybusidae was known from two incomplete specimens representing one generus,Stenocybus,from Dashankou fanua in Yumen,Gansu Province of China.The holotype of Stenocybus acidentatus is laterally compressed,making some characters unclear.Here we describe two new specimens of Stenocybus acidentatus from the same locality,an anterior portion of skull with articulated jaws,and a right dentary with nearly complete dentition.They show some detailed features on the morphology of the premaxilla,maxilla,nasal,external nares and dentary.The phylogenetic relationship between Stenocybus acidentatus and the relatively large Sinophoneus yumenensis is still difficult to determine,and needs more new complete material and further evidences.  相似文献   
283.
正Fluid inclusions in halite can directly record the major composition of seawater,however Ordovician halite is very rare.Ordovician is a key time during the evolution history.However there are no Ordovician seawater data reported except from the data from the halite from the  相似文献   
284.
正Introduction A 405-cm sediment section GM02 from Gomo Co salt lake in the northern Tibetan Plateau was used to reconstruct climate changes during marine isotope stage(MIS)2,including the Last Glacial Maximum(LGM)and last  相似文献   
285.
暴雨是诱发滑坡的重要因素之一,但目前对于暴雨作用下滑坡变形响应机制的研究仍不充分。该文以三峡库区白家包滑坡为例,在滑坡详细监测数据的基础上,分析了暴雨作用下白家包滑坡的变形响应特征;采用滑坡互信息量方法揭示了暴雨作用下降雨及库水位变动对白家包滑坡变形的影响规律。结果表明:白家包滑坡变形主要受库水位变动影响,坡表裂缝扩张主要受降雨影响;暴雨是诱发滑坡加速变形及边界处的坡表裂缝快速扩张的主要因素。该文的研究方法可推广到其它多条件联合作用下滑坡响应规律的分析,为类似暴雨作用下水库滑坡防灾减灾提供一定参考。  相似文献   
286.
Based on Chen et al. (2006), the scheme of the combination of the pentad-mean zonal height departure nonlinear prediction with the T42L9 model prediction was designed, in which the pentad zonal heights at all the 12-initial-value-input isobar levels from 50 hPa to 1000 hPa except 200, 300, 500, and 700 hPa were derived from nonlinear forecasts of the four levels by means of a good correlation between neighboring levels.Then the above pentad zonal heights at 12 isobar-levels were transformed to the spectrum coefficients of the temperature at each integration step of T42L9 model. At last,the nudging was made. On account of a variety of error accumulation, the pentad zonal components of the monthly height at isobar levels output by T42L9 model were replaced by the corresponding nonlinear results once more when integration was over. Multiple case experiments showed that such combination of two kinds of prediction made an improvement in the wave component as a result of wave-flow nonlinear interaction while reducing the systematical forecast errors. Namely the monthly-mean height anomaly correlation coe cients over the high- and mid-latitudes of the Northern Hemisphere, over the Southern Hemisphere and over the globe increased respectively from 0.249 to 0.347, from 0.286 to 0.387, and from 0.343 to 0.414 (relative changes of 31.5%, 41.0%, and 18.3%).The monthly-mean root-mean-square error (RMSE) of T42L9 model over the three areas was considerably decreased, the relative change over the globe reached 44.2%. The monthly-mean anomaly correlation coefficients of wave 4-9 over the areas were up to 0.392, 0.200, and 0.295, with the relative change of 53.8%, 94.1%,and 61.2%, and correspondingly their RMSEs were decreased respectively with the rate of 8.5%, 6.3%, and 8.1%. At the same time the monthly-mean pattern of parts of cases were presented better.  相似文献   
287.
To examine the correlation between the sizes of sea breeze fronts and pollutants under the influence of synoptic fields, a numerical simulation was conducted in the southeast coastal area of the Korean Peninsula, where relatively high concentrations of pollutants occur because of the presence of various kinds of industrial developments. Sea breeze and sea breeze front days during the period 2005-09 were identified using wind profiler data and, according to the results, the number of days were 72 and 53, respectively. When synoptic forcing was weak, sea breeze fronts moved fast both in horizontal fields and in terms of wind velocity, while in the case of strong synoptic forcing, sea breeze fronts remained at the coast or moved slowly due to strong opposing flows. In this case, the sea breeze front development function and horizontal potential temperature difference were larger than with weak synoptic forcing. The ozone concentration that moves together with sea breeze fronts was also formed along the frontal surfaces. Ozone advection and diffusion in the case of strong synoptic forcing was suppressed at the frontal surface and the concentration gradient was large. The vertical distribution of ozone was very low due to the Thermal Internal Boundary Layer (TIBL) being low.  相似文献   
288.
祁连山冻土区天然气水合物气体组分的 气相色谱法测定   总被引:2,自引:0,他引:2  
建立了气相色谱法测定祁连山冻土区天然气水合物C1~C5气体组分的分析方法,对比研究了单点法与多点法校正、外标法与外标归一化法定量,以及顶空法与排水法2种气体收集方式的区别。结果表明:顶空法制备、单点法校正、外标归一化法定量计算为气相色谱法测定天然气水合物气体组分的最佳方法, 方法相对标准偏差(RSD)为0~1.06%,检出限为0.0003%~0.0127%。通过对祁连山冻土区DK-2孔10个天然气水合物样品的测定,发现C1含量为60.64%~78.76%,C2含量为8.99%~13.60%,C3含量为6.58%~21.24%,C4和C5含量较少,可见C2+气体组分含量丰富,具有较低的C1/C2+比值(1.5~3.7),显示出明显的热解气特征。  相似文献   
289.
设计加工了一套研究水合物稳定务件的实验装置,采用多步加热分解法对不同浓度的盐溶液中的甲烷水合物稳定条件进行了初步研究.实验测定了4种不同浓度的NaBr和KBr溶液中甲烷水合物的P-T稳定条件,结果表明,相同浓度下Na+对稳定性的影响大于K+;当NaBr和KBr浓度均为0.2 mol/L时,其稳定点相对与纯水分别降低了(...  相似文献   
290.
城市地价水平随着城市社会经济的发展、基础设施建设的完善会不断变化,而基准地价成果奠定了城市地价的基础,对强化政府进行城市土地管理、地价水平宏观控制,防止国有  相似文献   
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