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21.
青岛台体应变短周期(小于128 min)气压系数2018-01出现阶变,通过对观测系统、台站周边施工情况、监测环境等逐项现场核实,排除观测系统、周边施工的影响。利用离散小波变换和回归分析发现,钻孔水位的气压系数与体应变气压系数同步阶变,结合台站钻孔施工当天体应变钻孔水位变化、体应变趋势变化、其他相邻台站水位气压系数变化等数据认为,台站钻孔施工是导致体应变气压系数变化的原因,并定性分析其变化机理。 相似文献
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《China Geology》2020,3(3):385-401
Recently, continuous breakthroughs have been made about deep gold prospecting in the Jiaodong gold province area of China. Approximately 5000 t of cumulative gold resources have been explored in Jiaodong, which has thus become an internationally noteworthy gold ore cluster. The gold exploration depth has been increased to about 2000 m from the previous <1000 m. To further explore the mineralization potential of the Jiaodong area at a depth of about 3000 m, the Shandong Institute of Geological Sciences has drilled an exploratory drillhole named “Deep drillhole ZK01” to a depth of 3266 m. Hence, as reported herein, the mineralization characteristics of the Jiaojia metallogenic belt have been successfully documented. ZK01 is, to date, the deepest borehole with an gold intersect in China, and constitutes a significant advance in deep gold prospecting in China. The findings of this study further indicate that the depth interval of 2000 m to 4000 m below the ground surface in the Wuyi Village area incorporates 912 t of inferred gold resources, while the depth interval of 2000 m to 4000 m below the surface across the Jiaodong area possesses about 4000 t of inferred gold resources. The Jiaojia Fault Belt tends to gently dip downward, having dip angles of about 25° and about 20° at vertical depths of 2000 m and 2850 m, respectively. The deep part of the Jiaojia metallogenic belt differs from the shallow and moderately deep parts about fracturing, alteration, mineralization, and tectonic type. The deep zones can generally be categorized from inside outward as cataclastic granite, granitic cataclasite, weakly beresitized granitic cataclasite, beresitized cataclasite, and gouge. These zones exhibit a gradual transitional relation or occur alternately and repeatedly. The mineralization degree of the pyritized cataclastic granite-type ore in the deep part of the Jiaojia metallogenic belt is closely related to the degree of pyrite vein development; that is, the higher the pyrite content, the wider the veins and the higher the gold grade. Compared to the shallow gold ores, the deep-seated gold ores have higher fineness and contain joseite, tetradymite, and native bismuth, suggesting that the deep gold mineralization temperature is higher and that mantle-sourced material may have contributed to this mineralization. ZK01 has also revealed that the deep-seated ore bodies in the Jiaojia metallogenic belt are principally situated above the main fracture plane (gouge) and hosted within the Linglong Granite, contradicting previous findings indicating that the moderately shallow gold ore bodies are usually hosted in the contact zone between the Linglong Granite and Jiaodong Group or meta-gabbro. These new discoveries are particularly significant because they can help correct mineralization prospecting models, determine favorable positions for deep prospecting, and improve metallogenic prediction and resource potential evaluation. 相似文献
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强化配筋连梁是指采用HRB400及以上钢筋、加密加粗腰筋、加粗箍筋的连梁。期望通过腰筋和箍筋形成的2层或更多层的高强钢筋网片来承受剪力,提高其抗震性能,施工较为方便,适用于小跨高比连梁。利用非线性有限元方法,在已完成普通配筋小跨高比连梁抗震性能试验的基础上,研究了跨高比为1.25的不同配筋形式连梁的抗震性能。研究表明:强化配筋连梁的骨架曲线出现2个峰值,峰值荷载为普通配筋连梁的1.37倍,其荷载下降速率约为普通配筋连梁的39.42%,具有较高的承载力。强化配筋连梁的峰值位移是集中对角斜筋、交叉斜筋和对角暗撑配筋连梁的三倍多,具有较强的变形能力。最后,建议采用深梁的方法计算强化配筋连梁的受剪承载力。 相似文献
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The strength and architecture of roots and other below-ground organs of riparian and aquatic plants affect plant resistance to uprooting and contribute to reinforcing river bank, bar and bed materials. Therefore, root properties are an important element in models for estimating river bank stability and such models may focus on the role of plants by using root strength–diameter relationships for the particular plant species that are present. Here we explore the degree to which there appear to be significant differences in strength–diameter relationships between and within species-specific data sets obtained for two riparian tree/shrub (Populus nigra, Salix alba) and two emergent aquatic macrophyte (Sparganium erectum, Phalaris arundinacea) species in different European river environments. While the analysed data sets were not specifically collected to answer these research questions, the results are sufficiently compelling to make the case for the collection of a more comprehensive data set and its rigorous analysis. This would allow recommendations to be made on the degree to which (i) species-specific or more general relationships between root/rhizome strength and diameter are appropriate, (ii) such relationships are applicable within and between rivers in different geographical regions and subject to different local environmental conditions, and (iii) further (minimalist) field observations are needed to calibrate such relationships for investigations of new locales or species. © 2018 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd. 相似文献
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颗粒物粒径分布(Particle Size Distribution, PSD)代表了颗粒物浓度与颗粒物粒径之间的关系, 影响着海洋生态环境和水体光学特性等。文章基于2016年夏季航次调查的生物光学剖面数据, 研究了南海海盆海域PSD的分布特征。研究发现, 幂律函数可以较好地拟合南海海盆区域的PSD, 对数空间中的实测的PSD与模拟的PSD平均决定系数高达0.95。PSD斜率(ξ)的分布范围为[1.27, 7.65], 均值为3.93±0.56。南海海盆区域表层水体的ξ均值与全球大洋表层水体的ξ均值相近, 但高于海湾等表层水体的ξ均值。ξ能较好地表征颗粒物平均粒径DA的大小, 两者存在明显负相关关系, 即ξ值越高, DA越小; 反之, DA越大。通过分析T1断面的生物光学剖面数据及总体平均的PSD剖面数据, 发现PSD剖面分布特征如下: 1)表层水体的ξ值相对较高, 且DA值相对较低, 推测可能是由于微微型藻类为主导颗粒物所致; 2) ξ值极小值层出现在次表层叶绿素浓度极大值层(Subsurface Chlorophyll Maximum Layer, SCML)中, 并伴随DA极大值层的出现, 其原因可能是SCML中的大粒径浮游植物占比显著增加; 3)弱光层中的ξ值较SCML中的高, 但略低于表层的ξ值, 而DA则位于表层与SCML的DA之间, 这可能与浮游植物及其碎屑的絮凝、分解、沉降等过程相关。PSD特征影响着海水的固有光学特性, 分析发现: 由于SCML中的叶绿素浓度增加, 颗粒物散射系数(bp(532))和颗粒物后向散射系数(bbp(532))也相应呈现显著增加的趋势。弱光层中的平均bp(532)与平均bbp(532)最小。ξ与颗粒物衰减光谱斜率之间呈高分散性, Boss 等(2001b) 的模型适合用于粗略估算区域性的ξ分布范围及均值。 相似文献
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钻探参数实时采集系统研制的目的是向钻探技术及管理人员提供直观的钻探实时参数,通过该系统可全天候的掌握钻探工况。钻探参数采集的方法是通过传感器采集压力、转速、位移、流量、液位等物理参数,使用配套的软硬件设备进行数据转换和处理,在人机交互界面显示直观的工程参数。该系统根据野外现场不同工作环境可以使用互联网、GPRS终端或者北斗卫星终端把现场实时工程数据无线传输至远程服务器上,用户通过手机或电脑即可查看到现场的实时或历史工程数据。采用本系统可以预防和减少钻探事故,为事故处理提供数据支撑,为实现钻探自动化、智能化提供基础数据。 相似文献
30.
位于中国和尼泊尔边境的西藏樟木口岸是国家一类陆路通商口岸,也是西藏最大的边贸中心口岸。2015年尼泊尔大地震之后,西藏樟木口岸因多次发生滑坡灾害,而导致口岸关闭。为了调查樟木口岸区域滑坡灾害的分布和变形情况及更好的服务于区域减灾防灾,利用InSAR技术对覆盖该区域的Sentinel-1A和ALOS-2两种卫星影像数据进行了处理,并通过分析视线向年均形变速率图,圈定了17处疑似滑坡,并对其中的5处典型滑坡进行时间序列形变特征分析,监测识别出的滑坡基本沿318国道所在一侧的波曲河左岸分布。InSAR调查结果表明受地震影响樟木地区的滑坡多分布在沿波曲河左岸的陡峭山体上,中尼公路迪斯岗至友谊桥段的古滑坡出现了局部复活的现象,同时樟木镇居民所在的城区也发育有扎美拉山危岩体崩塌滑坡灾害。 相似文献