Intrinsic and attenuative dispersion characteristics of direct P-waves in and near the source area of the 1999 MW7.6 Chi-Chi,Taiwan,earth-quake before and after the mainshock     

Xiqiang Liu  Chauhuei Chen Yanwen Zhou  Junhao Qu Earthquake Administration of Sh  ong Province  Ji'nan  China Institute of Seismology  National Chung Cheng University  Chiayi  Taiwan 《地震学报(英文版)》2009,(1):33-44

Based on the measurement of the arrival time of maxima magnitude from band-pass filtering signals which were determined using a new Morlet wavelet multiple-filter method,we develop a method for measuring intrinsic and attenuative dispersion of the first cycle direct P-wave.We determine relative group delays of spectral components of direct P-waves for 984 ray paths from SML and ALS stations of the Taiwan Central Weather Bureau Seismic Network(CWBSN).Using continuous relaxation model,we deduce a new transfer...  相似文献   

Early diagenetic deformation structures of the Furongian ribbon rocks in Shandong Province of China——A new perspective of the genesis of limestone conglomerates     

CHEN JiTao    HAN ZuoZhen  ZHANG XiaoLei  FAN AiPing & YANG RenChao College of Geological Science  Engineering  Sh  ong University of Science  Technology  Qingdao  China  School of Earth  Environmental Sciences  Seoul National University  Seoul -  South Korea 《中国科学:地球科学(英文版)》2010,(2)

Ribbon rocks are characterized by an alternation of millimeter-to centimeter-thick limestone and argillaceous deposits (marlstone or shale).The sedimentary processes and diagenetic characteristics of ribbon rocks might be critical to the formation of limestone conglomerates.According to detailed field measurement and laboratory analyses (thin section observation and XRD analysis),four types of ribbon rocks are classified,i.e.,limestone and marlstone couplet (L-M),limestone and shale couplet (L-S),thin-bedde...  相似文献   

山东雨季季内降水分型及旱涝并存与急转——气候特征     

于群  黄菲  王启  龚佃利  郑明玺 《热带气象学报》2011,(5):690-696

采用1965—2007年山东省地面测站的逐日降水量和同期NCEP日平均再分析资料,运用统计学方法,探讨了季内降水分型、季节内振荡及旱涝突变的气候特征。结果表明,主要分为全省一致Ⅰ、东西反相Ⅱ、南北反相Ⅲ三种类型。他们的季内旱涝急转显示了典型的气候意义,Ⅰ型在6月下旬旱涝急转、8月中旬后期和9月初涝旱急转,与山东“夏季”雨季开始、结束时间的关键期是一致的。分型不仅限于山东,而是有着更广的旱涝区域。当Ⅰ型正相位时500 hPa高度场对应亚欧-北太平洋中高纬度为正距平,Ⅱ型表现出西北太平洋西岸的PJ波列,Ⅲ型对应着从西太沿岸-美洲西岸的类PNA型遥相关。   相似文献   

太阳能电池在深海抗风浪养殖网箱中的应用研究     

宋协法  万荣  梁振林 《中国海洋大学学报(自然科学版)》2003,33(5):707-711

根据目前我国深海抗风浪网箱电力设备的配置情况 ,通过对 LA361 K51 S型太阳能电池性能的测试 ,确定了太阳电池的电流、电压、太阳强度及气温等随时间变化的规律以及天气变化情况对太阳电池的功率、转化效率的影响。在计算深海抗风浪网箱日用电量的基础上 ,对所需太阳电池的功率、蓄电池的容量进行了计算 ,并依此确定了深海抗风浪网箱配置太阳电池和蓄电池的规格及型号  相似文献   

大直径潜孔锤气力反循环流体速度与压力模型     

黄勇  殷琨  朱丽红  博坤 《吉林大学学报(地球科学版)》2011,(Z1):232-236

为解决大直径潜孔锤反循环钻进技术中气体携带岩屑不彻底和地面供气压力难以控制问题,必须开展循环气体流动参数即速度压力分布研究。根据反循环钻进中流体通道特点对流场分区,采用"倒算法"按循环系统流动的反方向推导各分区流场的气体速度和压力公式,建立流体参数数学模型,并对所得模型进行实例验算。以直径1.2 m、孔深40 m硬岩钻孔为例,钻孔出口流速为40 m/s时,钻头喷嘴气体流速为456 m/s,喷嘴截面积为0.002 4 m2,孔口气体注入压力为1.2 MPa,循环系统压力降约为0.9 MPa。计算结果表明,该模型可为地面气源参数调节和优化喷嘴结构提供依据。  相似文献   

高阶有限差分法管波传播数值模拟     

孟庆生  樊玉清  张珂  张盟 《吉林大学学报(地球科学版)》2011,41(1):292-298

为正确认识流体充填钻孔中管波的传播规律,首先给出均匀各向同性介质中包含流体充填钻孔条件下的弹性波动力学方程和二阶速度-应力公式及差分格式的稳定性条件和边界条件;然后利用高阶交错网格有限差分法,结合典型模型,模拟了不同时刻管波的传播快照和复杂层状介质中管波的合成地震记录,并与实际管波地震记录进行了对比。结果表明:在地层分界面、溶洞的边界等波阻抗差异界面处,管波都会产生反射;反射管波的振幅、频率特征受界面两侧的岩石物理性质差异的影响;在理论合成记录中,反射管波与直达管波同相轴的交点与理论模型中地层分界面或异常体的边界一致。  相似文献   

Crustal structure beneath Beijing and its surrounding regions derived from gravity data     

Wenliang Jiang Jingfa Zhang Xiaocui Lu  Jing Lu Institute of Crustal Dynamics  China Earthquake Administration  Beijing  China Science  Technology University of Sh  ong  Qingdao  China 《地震学报(英文版)》2011,(3):299-310

In this paper we use gravity data to study fine crustal structure and seismogenic environment beneath Beijing and its surrounding regions.Multi-scale wavelet analysis method is applied to separating gravity fields.Logarithmic power spectrum method is also used to calculate depth of gravity field source.The results show that the crustal structure is very complicated beneath Beijing and its surrounding areas.The crustal density exhibits laterally inhomogeneous.There are three large scale tectonic zones in ...  相似文献   

城市商业服务设施吸引力的空间相关性分析   总被引：1，自引：0，他引：1  

王汉东  乐阳  李宇光  黄玲 《武汉大学学报(信息科学版)》2011,36(9):1102-1106

利用武汉市出租车轨迹数据,根据服务设施的空间可达性,采用加权两步移动搜寻法计算服务设施的吸引力大小,并通过计算全局自相关指标分析服务设施吸引力在整体上的空间聚集特征,在此基础上分析服务设施吸引力的局部空间相关性。实验结果表明,武汉市服务设施吸引力整体上呈现显著的空间聚集特征,在商业繁华中心地带服务设施吸引力具有局部自相关性。  相似文献   

A multi-subwaveform parametric retracker of the radar satellite altimetric waveform and recovery of gravity anomalies over coastal oceans   总被引：3，自引：0，他引：3  

HWANG CheinWay 《中国科学:地球科学(英文版)》2010,(4)

The quality of satellite radar altimetric data is very important in studies of geodesy,geophysics,and oceanography.Over coastal oceans,altimeter waveforms are contaminated by the terrain and physical environments so that the accuracy of altimeter data is lower than that over open oceans.Here we develop a new multi-subwaveform parametric retracker(MSPR) to improve the quality of altimeter data for the recovery of gravity anomaly in coastal oceans.The least squares collocation method is used to recover the residual gravity anomaly over the coastal water from altimetric data.The waveform data records from Geosat/GM around Taiwan Island are practically retracked with MSPR.When compared with the Taiwan geoid height,the results retracked by MSPR are more accurate than those retracked by the well-known β-5-parmeter method and from the geophysical data records(GDRs).The gravity anomalies over Taiwan coastal waters are calculated from the retracked altimeter data with the least squares collocation.When we compared gravity anomalies computed using altimeter GDRs with the ship-borne gravity data over Taiwan coastal ocean,we found that the results from retracked data are more accurate than those from GDRs.  相似文献   

西北地区气候变化新动态及对干旱环境的影响——总体暖干化,局部出现暖湿迹象   总被引：12，自引：1，他引：11  

张强  张存杰  白虎志  李林  孙兰东  刘德祥  王劲松  赵红岩 《干旱气象》2010,28(1):1-7

近50 a来,西北地区气温呈显著的上升趋势,降水变化空间差异突出,西北地区整体暖干化趋势明显,局部出现暖湿现象。气候变暖使冰川退缩,雪线上升,冻土消融,湿地退化,湖泊萎缩,河流流量减少,水资源越来越短缺,出现生态环境恶化问题。根据IPCC预测结果分析,未来西北地区气候变暖趋势会更加明显。从保护西北地区生态环境、完善气候变化综合监测系统以及开展重点区域气候变化过程专项研究等方面提出了对策建议。  相似文献