河北省地质钻孔资料分析   总被引：3，自引：3，他引：0  

吕国军  李红梅  康江  孙丽娜 《地震地磁观测与研究》2017,38(2):125-131

地质钻孔资料是工程地质、矿产勘察等报告中广泛使用的资料,具有重要的二次开发和使用价值,对于工程项目的启动如:规划、设计、施工等具有重要意义。搜集河北省现有地质钻孔资料,给出该省钻孔分布图、场地类别分布图、各市等厚线图;以钻孔资料中剪切波速作为液化判别指标,判断场地液化情况;以邯郸地区钻孔资料为例,进行三维地层划分,与磁县断裂结合分析,发现断裂在地下的分布状态直观可见,从而为断裂分析提供一种直观手段。  相似文献   

2016年运城4.4级地震序列精定位及发震构造分析     

吴昊昱  吕睿 《地震地磁观测与研究》2017,38(5):8-13

根据2016年运城4.4级地震序列资料,进行余震精定位、主震震源机制和发震构造等研究。地震震中分布结果显示,本次地震的发生构造与以往该地区震群型地震发震构造不同,构造单元相对简单,发生在盐湖北岸断裂附近。余震双差精定位结果显示,余震优势分布呈NNE向,NW向也有零星活动。精定位后震源深度集中分布在15-24 km,平均深度20.2 km,断层剖面深度集中分布在18-23 km,倾向NW,与盆地地形构造吻合。采用Snoke与CAP方法得到的震源机制解基本一致,此次序列的主震错断方式为走滑兼逆冲,节面B参数与中条山山前断裂东段走向和倾向接近。综合认为,本次运城地震序列的余震呈NNE向优势分布,精定位结合地震震源机制结果,推断此次地震序列发震断裂为中条山山前断裂的NNE向隐伏断裂。  相似文献   

黄土边坡“三维最危险滑裂面”的高效搜索和稳定性评价   总被引：1，自引：1，他引：0  

黄雅虹  吕悦军  荣棉水  石玉成 《震灾防御技术》2017,12(1):125-132

本文介绍了作者所开发的一套实用型黄土坡体“三维最危险滑裂面”搜索和稳定性评价软件系统的核心思想,即采用Monte Carlo随机搜索法与遗传算法相结合的优化方法,高效生成一系列接近（或包含）“最危险滑裂面”的三维滑裂面,并以Hungr法所确定的稳定性系数最小为筛选依据,搜索确定任意形态黄土坡体的“三维最危险滑裂面”,进而基于已知的“三维最危险滑裂面”,进一步考虑各种可能的参数变化,进行严密的稳定性分析和评价。  相似文献   

三疣梭子蟹低盐适应相关的SNP开发     

冯艳艳  张德宁  吕建建  高保全  李健  刘萍 《海洋学报(英文版)》2019,38(8):41-47

盐度是影响三疣梭子蟹人工繁育非常重要的一个环境因素,抗低盐品系的三疣梭子蟹受到水产养殖界的广泛喜爱。分子标记辅助育种可以大大加快良种选育和性状改良的的过程,目前作为第三代的分子标记技术的SNP,广泛应用到三疣梭子蟹耐低盐品系选育过程中。本实验室已有的研究中,通过不同群体分别在盐度11和33下的基因表达差异,构建的比较转录组学数据中总共包含了615条与低渗调节相关的基因片段。为了发掘三疣梭子蟹与低盐适应相关SNP,本研究基于三疣梭子蟹比较转录组学数据研究结果,筛选出低盐调节相关候选基因片段50条,设计引物进行PCR扩增,共得到总长为18511 bp的DNA片段。通过直接测序法在低盐相关片段上发现了85个SNP位点,分布频率为0.46/100 bp,其中转换突变的比例为81%,颠换突变的比例为19%,转换的比例远远大于颠换,符合“transition bias”原理。C/T或G/A突变所占比例为55%;G/T或C/A比例为26%,A/T突变所占比例为12%,G/C突变比例为7%。通过飞行质谱法,在三疣梭子蟹低盐适应性状分离群体中各成功分型了23个SNP位点。通过卡方检验分析发现,8个SNPs与低盐适应显著相关（P<0.05）。其中有三个关联性SNP位点位于表皮蛋白基因上,有三个SNP位点位于三个新基因上,其他两个SNP位点分别位于水通道蛋白和氯离子通道蛋白基因上。这些标记的开发为三疣梭子蟹耐低盐新品种选育方法的建立奠定了良好的基础。  相似文献   

基于椭圆约束的隧道点云滤波     

吕亚磊  李永强  董亚涵  杨清科 《测绘工程》2019,28(5):44-50

针对激光LiDAR在隧道监测中隧道壁点云滤波问题,通过移动测量系统获取隧道点云数据,提出采用联合RANSAC和稳健最小二乘的点云滤波方法。首先根据移动测量航迹对点云进行里程赋值和断面切片划分,获得点云断面数据;其次通过RANSAC算法对隧道进行圆模型拟合,初步滤除加大粗差点。最后通过椭圆约束的稳健最小二乘进行精细滤波,滤除和隧道壁距离较近的粗差点,获得隧道壁点云,并拟合出隧道壁断面参数。对滤波结果进行精度评定和拟合结果的稳健分析,说明滤波结果的有效性和鲁棒性。  相似文献   

Sources of the Multi-Lane Type II Solar Radio Burst on 5 November 2014     

M. S. Lv  Y. Chen  C. Y. Li  I. Zimovets  G. H. Du  B. Wang  S. W. Feng  S. L. Ma 《Solar physics》2017,292(12):194

We report the well-observed event of a multi-lane type II solar radio burst with a combined analysis of radio dynamic spectra and radio and extreme-ultraviolet (EUV) imaging data. The burst is associated with an EUV wave driven by a coronal mass ejection (CME) that is accompanied by a GOES X-ray M7.9 flare on 5 November 2014. This type of event is rarely observed with such a complete data set. The type II burst presents three episodes (referred to as A, B, and C), characterized by a sudden change in spectral drift, and contains more than ten branches, including both harmonic-fundamental (H–F) pairs and split bands. The sources of the three episodes present a general outward propagating trend. There exists a significant morphology change from single source (Episode A) to double source (Episode B). Episode C maintains the double-source morphology at 150 MHz (no imaging data are available at a lower frequency). The double-source centroids are separated by \(\sim300 ^{\prime\prime}\) to \(500^{\prime\prime}\). The southeastern (SE) source is likely the continuation of the source of Episode A since both are at the same section of the shock (i.e. the EUV wave) and close to each other. The northwestern (NW) source is coincident with (thus, possibly originates from) the interaction of the shock with a nearby mini-streamer-like structure. Comparing the simultaneously observed sources of the F and H branches of Episode A, we find that their centroids are separated by less than \(200^{\prime \prime}\). The centroids of the split bands of Episode B are cospatial within the observational uncertainties. This study shows the source evolution of a multi-lane type II burst and the source locations of different lanes relative to each other and to the EUV wave generated by a CME. The study indicates the intrinsic complexity underlying a type II dynamic spectrum.  相似文献   

Energy-based dynamic parameter identification for Pasternak foundation model     

Wang-Xi Zhang  Wei-Lei Lv  Jin-Yi Zhang  Xiong Wang  Hyeon-Jong Hwang  Wei-Jian Yi 《地震工程与工程振动(英文版)》2021,20(3):630-642

Parameter identification of Pasternak foundation models(PFM) is never satisfactory, which discourages the application and popularization of PFM. In the present study, an energy-based model to predict the dynamic foundation coefficients was proposed using the vibration kinetic energy and potential energy of a Pasternak foundation-rigid plate system. On the basis of the Pasternak foundation, the relationship among the natural frequency, dynamic foundation coefficients, rigid plate configuration, and vibrating soil equivalent mass per unit area was considered. To obtain the natural frequencies of the Pasternak foundation-rigid plate system, dynamic tests were performed. Using two or more dynamic test results of various rigid plates on a foundation, a set of equations of dynamic foundation coefficients was set up to directly identify the foundation coefficients and equivalent mass per unit area of vibrating soil. The feasibility of the proposed method was verified by comparing it with the outdoor and indoor test results and finite element analysis results. When the proposed method is used to obtain the dynamic parameters, PFM can be generalized and applied more widely in engineering practice.  相似文献   

一种模拟舰艇全磁场的二轴磁体设计          下载免费PDF全文

陈浩  林春生  吕红伟 《数字海洋与水下攻防》2018,1(1):20-24

为了解决单轴磁体模拟舰船磁场的不足,提出了一种二轴磁体的模拟方法。 采用了一种同铁芯、两绕组、同轴线和不同绕制方法的二轴磁体的设计方案。 经过严格的设计计算,确定了各设计参数,同时按 10：1 的比例制作了磁体模型,并进行了模型磁场的测量实验。 最后对二轴磁体进行了总体优化设计和性能评估分析,对其他新型磁体的设计具有一定的参考价值。  相似文献   

Seismogenic structures of the 2006 M<Subscript>L</Subscript>4.0 Dangan Island earthquake offshore Hong Kong     

Shaohong Xia  Jinghe Cao  Jinlong Sun  Jinshui Lv  Huilong Xu  Xiang Zhang  Kuiyuan Wan  Chaoyan Fan  Pengxiang Zhou 《中国海洋大学学报(英文版)》2018,17(1):169-176

The northern margin of the South China Sea, as a typical extensional continental margin, has relatively strong intraplate seismicity. Compared with the active zones of Nanao Island, Yangjiang, and Heyuan, seismicity in the Pearl River Estuary is relatively low. However, a M_L4.0 earthquake in 2006 occurred near Dangan Island (DI) offshore Hong Kong, and this site was adjacent to the source of the historical M5.8 earthquake in 1874. To reveal the seismogenic mechanism of intraplate earthquakes in DI, we systematically analyzed the structural characteristics in the source area of the 2006 DI earthquake using integrated 24-channel seismic profiles, onshore–offshore wide-angle seismic tomography, and natural earthquake parameters. We ascertained the locations of NW- and NE-trending faults in the DI sea and found that the NE-trending DI fault mainly dipped southeast at a high angle and cut through the crust with an obvious low-velocity anomaly. The NW-trending fault dipped southwest with a similar high angle. The 2006 DI earthquake was adjacent to the intersection of the NE- and NW-trending faults, which suggested that the intersection of the two faults with different strikes could provide a favorable condition for the generation and triggering of intraplate earthquakes. Crustal velocity model showed that the high-velocity anomaly was imaged in the west of DI, but a distinct entity with low-velocity anomaly in the upper crust and high-velocity anomaly in the lower crust was found in the south of DI. Both the 1874 and 2006 DI earthquakes occurred along the edge of the distinct entity. Two vertical cross-sections nearly perpendicular to the strikes of the intersecting faults revealed good spatial correlations between the 2006 DI earthquake and the low to high speed transition in the distinct entity. This result indicated that the transitional zone might be a weakly structural body that can store strain energy and release it as a brittle failure, resulting in an earthquake-prone area.  相似文献   

Crustal structure revealed by a deep seismic sounding profile of Baijing-Gaoming-Jinwan in the Pearl River Delta     

Xiang Zhang  Xiuwei Ye  Jinshui Lv  Jinlong Sun  Xiaona Wang 《中国海洋大学学报(英文版)》2018,17(1):186-194

The Pearl River Estuary area, located in the middle part of the southern China coastal seismic belt, has long been considered a potential source of strong earthquakes above magnitude 7.0. To scientifically assess the potential strong earthquake risk in this area, a three-dimensional artificial seismic sounding experiment, consisting of a receiving array and seabed seismograph, was performed to reveal the deep crustal structure in this region. We used artificial ship-borne air-gun excitation shots as sources, and fixed and mobile stations as receivers to record seismic data from May to August 2015. This paper presents results along a line from the western side of the Pearl River Estuary to the western side of the Baijing-Gaoming-Jinwan profile. A two-dimensional velocity structure was constructed using seismic travel-time tomography. The inversion results show that the Moho depth is 27 km in the coastal area and 30 km in the northwest of the Pearl River Estuary area, indicating that the crust thins from land to sea. Two structural discontinuities and multiple low-velocity anomalies appear in the crustal section. Inside both discontinuity zones, a low-velocity layer, with a minimum velocity of 6.05 km s~(-1), exists at a depth of about 15 km, and another, with a minimum velocity of 6.37 km s~(-1), exists at a depth of about 21.5 km between the middle and lower crust. These low velocities suggest that the discontinuities may consist of partly molten material. Earthquakes with magnitudes higher than 5.0 occurred in the low-velocity layer along the profile. The deep Kaiping-Enping fault, rooted in the crust, may be one of the most important channels for deep material upwelling and is related to tectonic movement since the Cretaceous in the Pearl River Delta tectonic rift basin.  相似文献