潍北-莱州湾凹陷郯庐断裂带新生代走滑特征

横切潍北-莱州湾凹陷郯庐断裂带的地震反射剖面和断裂带内的凹陷断层、沉积相和油气特征,直接或间接显示了郯庐断裂带的延伸、运动性质和活动时限。郯庐断裂带在海域和陆上的几何形态及其组合基本一致,根据切过断裂带的剖面和平面上断层的组合特征,判断其为兼具垂直位移的走滑运动断层系。走滑断裂带的活动控制着凹陷内同构造沉积以及构造样式,表明郯庐断裂带的活动时限具分段性,相当于渤海湾盆地孔店组(E1?2k)-沙四段(E2?3s4)沉积期(古新世-早始新世)-孔店组-沙二段(E2?3s2)沉积期(古新世-始新世)-孔店组-沙一段(E2?3s1)(古新世-渐新世)沉积时期,走滑拉分活动由南向北迁移; 活动方式也由古新世-早始新世的左旋走滑活动,被早始新世之后的右旋走滑活动所替代。     

基于微服务架构的地震站网全流程一体化监控平台设计与实现

地震站网全流程一体化监控平台是基于微服务框架,应用数据库、通信、并行计算等传统信息技术,结合新兴的云计算、大数据进行建设的信息服务平台。该平台采用Hadoop分布式处理方案,应用Spring Cloud框架搭建,进行Docker容器封装,以标准RESTful API作为服务接口的微服务架构,实现了各应用服务模块之间的高内聚、低耦合及灵活、可扩展的特性,最终实现对地震台站运行的实时监测、高效运维和一体化管理。     

滇西兰坪盆地五茂林剖面下白垩统景星组沉积相

实测了云南西部兰坪盆地东部下白垩统下部景星组的五茂林剖面,建立了曲流河、三角洲和湖泊3种沉积序列,其中三角洲序列在云南下白垩统中属首次建立。分析了粗碎屑岩的组成,将该剖面上出露的砾岩分成4类。早白垩世时兰坪盆地属丹那沙林-高黎贡弧的弧后盆地,景星组自下而上为曲流河沉积、三角洲沉积和湖泊沉积,且随湖侵发生,湖泊向西扩大。     

Solar Radio Spikes in 2.6 – 3.8 GHz during the 13 December 2006 Event

On 13 December 2006, some unusual radio bursts in the range 2.6?–?3.8 GHz were observed during an X3.4 flare/CME event from 02:30 to 04:30 UT in active region NOAA 10930 (S06W27) with the digital spectrometers of the National Astronomical Observatories of China (NAOC). During this event many spikes were detected with the high temporal resolution of 8 ms and high frequency resolution of 10 MHz. Many of them were found to have complex structures associated with other radio burst types. The new observational features may reflect certain emission signatures of the electron acceleration site. In this paper, we present the results of the analysis of the new observational features of the complex spikes. According to the observed properties of the spikes, we identify five classes. Their observational parameters, such as duration, bandwidth, and relative bandwidth, were determined. Most spikes had negative polarization, but spikes with positive polarization were observed during a short time interval and were identified as a separate class. Based on the analysis of observations with Hinode/SOT (Solar Optical Telescope) we suggest that the sources of the spikes with opposite polarizations were different. Combined observations of spikes and fiber bursts are used to estimate the magnetic field strength in the source.     

Characteristics and circulation background of extreme precipitation over East China

Natural Hazards - Using the observed daily precipitation data across East China, this paper analyzes spatiotemporal changes of annual and seasonal extreme precipitation indices during...     

铜官山S状背斜构造综合解析

通过褶皱、断裂、节理、线理等构造形迹的系统观测对铜官山S状背斜的形成过程和机制进行了综合构造解析,发现该背斜经过了3次构造变形,2次构造叠加复合.早期NE向褶皱的S状弯曲是由于前期EW向断裂限制的结果;晚期S状弯曲是由于新华夏构造应力场导致轴近水平的麻花状旋扭的结果;还通过物理模拟和数字模拟验证了限制型及麻花型S状构造形成机制.值得注意的是,通过铜官山S状背斜的综合构造解析可以扩大到整体下扬子台褶带的构造演化力学解析.从而证明根据局部地区的构造综合解析才是认识区域大地构造运动方式、方向及其变化最直接、最可靠的证据.     

Geological and geochemical characteristics of the Baogudi Carlin-type gold district (Southwest Guizhou,China) and their geological implications

The newly discovered Baogudi gold district is located in the southwestern Guizhou Province, China, where there are numerous Carlin-type gold deposits. To better understand the geological and geochemical characteristics of the Baogudi gold district, we carried out petrographic observations, elemental analyses, and fluid inclusion and isotopic composition studies. We also compared the results with those of typical Carlin-type gold deposits in southwestern Guizhou. Three mineralization stages, namely, the sedimentation diagenesis, hydrothermal (main-ore and late-ore substages), and supergene stages, were identified based on field and petrographic observations. The main-ore and late-ore stages correspond to Au and Sb mineralization, respectively, which are similar to typical Carlin-type mineralization. The mass transfer associated with alteration and mineralization shows that a significant amount of Au, As, Sb, Hg, Tl, Mo, and S were added to mineralized rocks during the main-ore stage. Remarkably, arsenic, Sb, and S were added to the mineralized rocks during the late-ore stage. Element migration indicates that the sulfidation process was responsible for ore formation. Four types of fluid inclusions were identified in ore-related quartz and fluorite. The main-ore stage fluids are characterized by an H₂O–NaCl–CO₂–CH₄ ± N₂ system, with medium to low temperatures (180–260 °C) and low salinity (0–9.08% NaCl equivalent). The late-ore stage fluids featured H₂O–NaCl ± CO₂ ± CH₄, with low temperature (120–200 °C) and low salinity (0–7.48% NaCl equivalent). The temperature, salinity, and CO₂ and CH₄ concentrations of ore-forming fluids decreased from the main-ore stage to the late-ore stage. The calculated δ¹³C, δD, and δ¹⁸O values of the ore-forming fluids range from − 14.3 to − 7.0‰, −76 to −55.7‰, and 4.5–15.0‰, respectively. Late-ore-stage stibnite had δ³⁴S values ranging from − 0.6 to 1.9‰. These stable isotopic compositions indicate that the ore-forming fluids originated mainly from deep magmatic hydrothermal fluids, with minor contributions from strata. Collectively, the Baogudi metallogenic district has geological and geochemical characteristics that are typical of Carlin-type gold deposits in southwest Guizhou. It is likely that the Baogudi gold district, together with other Carlin-type gold deposits in southwestern Guizhou, was formed in response to a single widespread metallogenic event.

     

Modelling the transverse behaviour of circular tunnels in structured clayey soils during earthquakes

Acta Geotechnica - The paper presents novel results from advanced numerical simulations of the transverse behaviour of shallow circular tunnels in natural clays accounting for soil structure...     

细菌反硝化法测试硝酸盐氮、氧同位素的研究与应用

为了验证细菌反硝化法对水体中硝酸盐氮、氧同位素组成测定的适用性、重现性及准确性, 在不同时间(2019年7月28日、8月19日、8月26日)利用反硝化细菌分别将海水、湖水和自来水样品中的硝酸盐转化为氧化亚氮（N₂O）, 并进行氮、氧同位素测定。结果表明, 不同时间段3个批次实验的硝酸盐氮同位素校准曲线斜率都接近理论值1, 相关性系数均高于0.999, 说明反硝化细菌在将样品中的硝酸盐全部还原为N₂O的过程中氮同位素分馏效应很小; 同一样品3个批次测定的硝酸盐的氮同位素值基本相同, 表明细菌反硝化法对硝酸盐氮同位素的测定在长时间周期内具有很好的重现性和准确性。3个批次氧同位素校准曲线斜率稳定在0.61～0.63之间, 相关性系数均高于0.99, 单批次内海水、湖水和自来水3类样品中硝酸盐氧同位素比值的标准偏差范围在0.18‰～0.69‰之间, 表明经过氧同位素校准曲线的校正, 可以准确反映样品中硝酸盐氧同位素组成; 同一样品3个批次测定的氧同位素值差异较大, 其变化范围为1.33‰～16.38‰, 可能是由于样品储存过程中硝酸盐与水之间发生的氧同位素交换作用所致。