Large-scale Migration of Fluids toward Foreland Basins during Collisional Orogeny: Evidence from Triassic Anhydrock Sequences and Regional Alteration in the Middle-Lower Yangtze Area

The middle-lower Yangtze area underwent a series of complex tectonic evolution, such as Hercynian extensional rifting, Indosinian foreland basining, and Yanshanian transpression-transtension, resulting in a large distinctive Cu-Fe-Au metallogenic belt. In the tectonic evolution, large-scale migration and convergence of fluids toward foreland basins induced during the collisional orogeny of the Yangtze and North China continental blocks were of vital importance for the formation of the metallogenic belt. Through geological surveys of the middle-lower Yangtze area, three lines of evidence of large-scale fluid migration are proposed: (1) The extensive dolomitic and silicic alteration penetrating Cambrian-Triassic strata generally occurs in a region sandwiched between the metallogenic belt along the Yangtze River and the Dabie orogenic belt, and in the alteration domain alternately strong and weak alteration zones extend in a NW direction and are controlled by the fault system of the Dabie orogenic belt; it might record the locus of the activities of long-distance migrating fluids. (2) The textures and structures of very thick Middle-Lower Triassic anhydrock sequences in restricted basins along the river reveal the important contribution of the convergence of regional hot brine in restricted basins and the chemical deposition or their formation. (3) Early-Middle Triassic syndepositional iron carbonate sequences and Fe-Cu-Pb-Zn massive sulfide deposits alternate with anhydrock sequences or are separated from the latter, but all of them occur in the same stratigraphic horizon and are intimately associated with each other, being the product of syndeposition of high-salinity hot brine. According to the geological surveys, combined with previous data, the authors propose a conceptual model of fluid migration-convergence and mineralization during the Dabie collisional orogeny.

Analysis of the Comparison of Twice Regional Large Rainstorms in Northwest Yantai City

[Objective] The twice regional rainstorms in northwest Yantai in July in 2009 and July in 2010 were expounded.[Method] The twice regional rainstorm in northwest Yantai in July in 2009 and July in 2010 were selected for comparison analysis by dint of conventional and non-conventional weather data,from the aspects of circulation background,physics quantity,and radar echo,etc.[Result] The twice large rainstorm process were regional convective strong precipitation.The rainstorm fell in the northwest of Yantai and had a strong precipitation center above 200 mm.The twice large rainstorm was affected by subtropical and shear line.The rainstorm area was related to the location of 588 dagpm line,westerly trough,and shear line.It was regional rainstorm of typical subtropical edge warm and wet airstream,combination of low vortex and shear line of westerly.The precipitation occurred around the center of water vapor flux;K index had pretty good indication effects to the generation of rainstorm.Large rainstorm occurred around the place with high K index.The K index of twice large rainstorm was larger than or equal to 34 ℃,and was close to the rainstorm falling area where K index was larger than or equal to 35 ℃.The reflection factor of twice large rainstorms at 0.5° elevation,the largest echo intensity was from 55 to 60 dBz,in strip echo from south to north,through the west peninsula,forming train effect.The data report product also had important reference basis for the report of regional large rainstorm.[Conclusion] The study provided references and basis for the report of large rainstorm in the future.

Quantitative Prediction of Concentrated Regions of Large and Superlarge Deposits in China

Identification and quantitative prediction of large and superlarge mineral deposits of solid mineral resources using the mineral resource prediction theory and method with comprehensive information is carried out nationwide in China at a scale of 1∶5 000 000. Using deposit concentrated regions as the model units and concentrated mineralization anomaly regions as prediction units, the prediction is performed on GIS platform. The technical route and research method of locating large and superlarge mineral deposits and principle of compiling attribute table of independent variables and functional variables are proposed. Upon methodology study, the qualitative locating and quantitative predicting mineral deposits are carried out with quantitative theory Ⅲ and characteristic analysis, respectively, and the advantage and disadvantage of two methods are discussed. This research is significant for mineral resource prediction in ten provinces of western China.

Metallogenic mechanisms of super-large Cu and Au deposits in the Dexing region and simulating experiments

Based on the results of previous studies and under the direction of the theory of "ore deposit genesis",the authors made use of high temperature and high pressure experimental facilities and conditions at the Tectono-geochemistry Research Room under the State Key Laboratory of Ore Deposit Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,and put the focus on the multi-source of tectonically controlling ore-forming materials,the characteristics of multi-stage and multi-episode hydrothermal activities and mineralization and the characteristics of multi-genesis and multi-ore deposition so as to shed light on the metallogenic mechanisms of super-large Cu and Au deposits.In addition simulating experiments were made on multi-stage and multi-episode tectonic activities and rock and ore deformation,multi-stage and multi-episode tectonic activities and mobilization and migration of ore-forming materials,and multi-stage and multi-episode tectonic activities and superimposition and enrichment of ore-forming materials.The experimental results showed that under the action of multi-stage and multi-episode tectonic stress the deformation and fragmentation of not only rocks and ores have been intensified,and but also the ore-forming materials originally disbursed in the rocks and ores have been mobilized and migrated and superimposed and enriched.The experimental results also provided the scientific experimental data and grounds for deep-going research on the rules of metallogenesis and geneses of super-large ore deposits in the Dexing region,Jiangxi Province.

REGION-WISE VARIATIONAL PRINCIPLES AND GENERALIZED VARIATIONAL PRINCIPLES ON LARGE STRAIN FOR CONSOLIDATION THEORY

The difference of constitutive character and large deformation as to soil mass are basic questions to analyze deformational feature. According to the description method of limited deformation, the large deformation consolidation equations of soil mass were created and its variational principles were rigorously testified. The regionwise variational principles of consolidation theory were deduced using sub-structure continuous condition of region-wise. Quoting the method of Lagrangian multiplier operator, generalized variational principles of region-wise of large deformation consolidation in the nonconstrained condition were created and approved.

Formation conditions and exploration direction of large natural gas reservoirs in the oil-prone Bohai Bay Basin, East China

The Bohai Bay Basin is a typical oil-prone basin, in which natural gas geological reserves have a small proportion. In this basin, the gas source rock is largely medium-deep lake mudstone with oil-prone type Ⅱ2-Ⅱ1 kerogens, and natural gas preservation conditions are poor due to active late tectonic movements. The formation conditions of large natural gas fields in the Bohai Bay Basin have been elusive. Based on the exploration results of Bohai Bay Basin and comparison with large gas fields in China and abroad, the formation conditions of conventional large-scale natural gas reservoirs in the Bohai Bay Basin were examined from accumulation dynamics, structure and sedimentation. The results show that the formation conditions of conventional large natural gas reservoirs in Bohai Bay Basin mainly include one core element and two key elements. The core factor is the strong sealing of Paleogene "quilt-like" overpressure mudstone. The two key factors include the rapid maturation and high-intensity gas generation of source rock in the late stage and large scale reservoir. On this basis, large-scale nature gas accumulation models in the Bohai Bay Basin have been worked out, including regional overpressure mudstone enriching model, local overpressure mudstone depleting model, sand-rich sedimentary subsag depleting model and late strongly-developed fault depleting model. It is found that Bozhong sag, northern Liaozhong sag and Banqiao sag have favorable conditions for the formation of large-scale natural gas reservoirs, and are worth exploring. The study results have important guidance for exploration of large scale natural gas reservoirs in the Bohai Bay Basin.

Validating the Runoff from the PRECIS Model Using a Large-Scale Routing Model

The streamflow over the Yellow River basin is simulated using the PRECIS （Providing REgional Climates for Impacts Studies） regional climate model driven by 15-year （1979-1993） ECMWF reanalysis data as the initial and lateral boundary conditions and an off-line large-scale routing model （LRM）. The LRM uses physical catchment and river channel information and allows streamflow to be predicted for large continental rivers with a 1°×1° spatial resolution. The results show that the PRECIS model can reproduce the general southeast to northwest gradient distribution of the precipitation over the Yellow River basin, The PRECIS- LRM model combination has the capability to simulate the seasonal and annual streamflow over the Yellow River basin. The simulated streamflow is generally coincident with the naturalized streamflow both in timing and in magnitude.

Application of Frontotemporal Expanded Flap with Bilateral Superficial temporal vessels in Repair of Large Area Scar Contracture in Face and Neck

Objective To summarize the clinical experience of frontotemporal expanded flap with bilateral superficial temporal vessels in repairing large area scar contracture in face and neck.Methods 14 patients with facial and Cervical scar contracture in our hospital were taken as the research object.With bilateral superficial temporal vessels as pedicles,a 400-600 ml skin dilator was inserted into the forehead and 50-100 ml skin dilator was inserted into the two temporal parts respectively.Within 3-4 months,the water injection volume reaches 2 times of the dilator volume.After maintaining for one month,skin flap transplantation was performed.The frontal flap was reserved for hairline reconstruction,and the flap was cut to cover the area after facial and Cervical scar release to reconstruct the jaw-neck angle.The pedicle division and pedicle trimming were performed 3-4 weeks after operation.Results All the 14 patients completed the operation successfully.The flap expansion time is 5-6 months.The expanded skin flap covers an area of 26 cm×9 cm-42 cm×16 cm,and all the skin flaps survived after operation.Among them,2 patients suffered from flap congestion after flap transplantation.Follow-up for 6-12 months showed that the color and texture of the skin flap were similar to those of facial skin,with natural transition and no obvious bloating.The angle between the lower jaw and the neck is about 90.The anterior flexion,posterior extension,lateral flexion and rotation of the neck are obviously improved compared with the anterior,and the posterior extension is close to normal.Conclusion Frontotemporal expanded flap with bilateral superficial temporal vessels is suitable for patients with large-area scar contracture in face and neck that cannot be repaired after expansion of adjacent local normal tissues.

软黏土地区深大基坑工程桩-连续墙体系空间变形效应

土体开挖过程中深大基坑存在明显的空间变形效应,对其主体结构力学行为产生影响。以新建苏州南站枢纽深大基坑为工程背景,考虑地连墙厚度及工程桩的影响,基于ABAQUS建立三维空间有限元模型,采用修正剑桥模型考虑软黏土的应变硬化特征,从地连墙侧向位移、墙后地表沉降、工程桩和坑底土体隆起3个方面,研究软黏土地区深大基坑工程桩-连续墙体系的变形特征及空间效应。研究结果表明:深大基坑地连墙的侧向位移和地表沉降均呈现明显的角部效应,基坑A区(地连墙厚度1 m、桩径1 m)地连墙侧向位移角部效应的影响范围为1.05~1.71倍开挖深度,基坑B区(地连墙厚度0.8 m、桩径1.5 m)地连墙侧向位移角部效应的影响范围为0.91~1.48倍开挖深度;基坑A区、B区地表沉降角部效应的影响范围分别为1.24~2.10和1.77~2.47倍开挖深度;深大基坑空间变形角部效应与工程桩桩径及地连墙厚度有关,并且对基坑长边的影响效果大于短边。工程桩可有效增大基坑开挖面以下土体的刚度,减小地连墙的侧向位移;增大地连墙厚度可有效降低基坑的整体变形。基坑工程桩与坑底土体隆起总体呈现中间大、周边小的特征,工程桩周边土体受其约束,隆起较小;在一定范围内,工程桩对土体隆起抑制作用与其桩径呈正相关,与其桩间距呈负相关。软黏土地区深大基坑设计计算中需关注工程桩-连续墙结构体系的空间变形效应。

一种大尺度区域GNSS坐标时间序列自适应时空滤波方法

提出一种GNSS坐标时间序列自适应时空滤波方法,在规定阈值下将滤波区域自适应分为若干个子区域,进行共模误差的提取和去除。对陆态网184个GNSS站点垂向坐标序列进行时空滤波,3组随机实验中,自适应PCA时空滤波后的站点序列平均RMS值减少约39.7%、38.4%和39.7%,且优于整体PCA滤波。进一步分析滤波前后站点噪声特性变化,结果显示,相比于整体PCA滤波,自适应滤波方法中站点残差序列幂律噪声减少约17.8%。

五措并举提升大型仪器设备共享成效的探索

大型仪器设备是高校提高教学科研水平和人才培养质量的重要条件,是反映学校的综合实力和办学水平的重要指标。随着高等教育的发展,高校大型仪器设备的类型和数量在不断增加,由此也带来了重复购置、利用率低等问题。通过加大大型仪器设备信息化共享、加强大型仪器设备人员队伍建设、建立健全大型仪器设备共享机制、探索大型仪器全成本核算管理、强化大型仪器设备制度集成创新,形成以内循环为主、区域化为辅的共享模式,全面提升大型仪器设备共享实效。

施工期铁路隧道软岩大变形快速分级方法研究

研究目的:西南复杂艰险山区等典型构造活跃区的构造地质环境复杂,断裂、褶皱发育,构造应力显著,铁路隧道围岩大变形问题突出,随着构造活跃区铁路隧道工程日益增加,将面临更严峻的大变形问题。在隧道施工开挖过程中,快速判别可能发生的大变形等级,有利于施工工法的调整和支护措施的制定。研究结论:(1)深入分析构造软岩大变形工程案例,以施工期掌子面开挖揭示围岩分级数据为基准,结合区域地应力、岩层厚度、岩性等大变形关键控制因素,快速判定大变形等级,提出了施工期铁路隧道围岩大变形快速分级方法,并结合典型工程案例对分级方法的有效性和准确性进行了验证;(2)本研究成果可应用于施工期间铁路隧道开挖围岩大变形的快速分级,适用于工程地质勘察领域。

考虑机会充电与行程时间可靠性的区域多车型电动公交调度优化

为提高电动公交系统运营效率,降低运营成本,本文提出一种考虑机会充电和行程时间可靠性的电动公交调度优化方法。首先,基于区域调度场景,提出在线路始末站配备快速充电桩,利用车次接续时间进行机会充电的策略;然后,考虑行程时间的随机波动,以表征特定可靠性的预留行程时间作为模型输入生成调度方案,同时,将发车延误成本纳入目标函数中,综合考虑公交企业从规划到运营阶段的整体效益,构建以总成本最小为目标的区域多车型电动公交调度优化模型,针对模型特点,设计自适应大邻域搜索算法进行求解;最后,以北京市大兴区4条公交线路为例,验证模型和算法的有效性。结果表明:基于本文方法得到的最优调度方案相较于传统单线路单车型调度方案,能使企业日均总成本下降37.93%,平均每辆车的发车延误时长减少5.63 min,说明本文所提方法能有效降低企业成本,提升公交系统可靠性。相较于不考虑机会充电和行程时间可靠性的区域多车型运营模式,本文最优方案能使总成本下降28.67%。此外,通过灵敏度分析,建议公交企业以240 kW的充电功率进行快速充电资源的配置,以90%的行程时间可靠性进行电动公交调度方案的编制。

大区域实景三维模型拼接融合方法及应用

随着实景三维中国建设的开展,大区域实景三维重建与更新已成为迫切需求,其建模面积大、模型成果异构、多尺度等特点导致场景拼接与融合成为丞待解决的问题,本文分别从影像及控制点重叠建立空三工程、包含相同控制点的空三工程融合2个角度,探究了从数据处理中实现三维场景拼接的方法,其次从模型成果的角度通过邻域瓦块的几何拓扑优化实现三维场景无缝拼接,文章对3种方法进行了试验对比及适用性分析,该研究解决了大场景三维模型拼接的问题,促进了实景三维高效高质建设。

贵州裸露岩溶地下河系统污染通道识别钻探技术

贵州裸露岩溶区地下河系统发育、岩溶发育强烈、水文地质条件复杂,地下河系统易受地面污染源渗滤液浸入引发严重污染问题。地下河系统污染通道隐蔽性强、空间狭窄、各向发育不均匀,精准识别难度大。为揭露识别污染通道,钻探成孔施工面临软硬互层与软弱不均、强岩溶地层易孔斜、大溶洞钻孔轴线易偏移和套管拆断、自然水力坡度小的地下河系统示踪剂迁移缓慢等难题,污染通道揭露识别难度大、效率低。采用防斜保直、大岩溶套管穿越封隔、孔内激化促示踪剂迁移等技术措施,保证了勘查孔垂直度,并为测井、示踪试验及水样采集等工作提供精准的钻孔通道,实现了污染通道的精准揭露和快速识别。对同类地层精准揭露和高效识别污染通道的钻探施工有参考和借鉴意义。

1981~2020年华南地区区域性极端降水事件研究

基于华南地区176个国家级自动气象站资料以及1981~2020年ECMWF ERA5再分析资料,采用区域性极端事件的客观识别方法(OITREE)、合成分析等方法,本文研究了华南地区区域性极端降水事件的时空分布特征,并分析了事件偏多年及偏少年的大尺度环流特征。主要结论如下:区域性极端降水事件的频次在年际尺度上的周期变化较为明显,并具有较明显的月变化特征,高发时段为5~6月;在极端强度及影响范围上,华南地区大部分区域性极端降水事件强度约130 mm d^(-1),较少事件强度超出320 mm d^(-1),且区域性极端降水事件的影响范围呈显著上升趋势(约310 km^(2)a^(-1));在事件的综合强度上,综合指数Z呈现显著的上升趋势[0.05(10 a)^(-1)],表明事件强度呈现显著增加的趋势;在大湾区及广东北部,区域性极端降水事件的累计降水及其对总降水的贡献呈显著上升趋势,而在广西南部地区,两者呈下降趋势;在事件偏多年,华南地区存在显著的西南风水汽输送及整层水汽通量强辐合的特征,而在事件偏少年,华南地区具有整层水汽通量辐合偏弱的特征;一般降水日,850 hPa上华南地区位于弱偏东南风区,区域性极端降水事件降水日,华南地区位于气旋性环流的东南部,受到明显的西南风风速大值带影响。

面向大规模农田的农机跨区作业紧急调配研究

针对大规模农田的粮食抢收工作,由于抢收约束时间的限制,导致可能无法在规定时间内完成所有粮食的收割任务,此时则会出现粮食损失值。构建以粮食损失值最小化为目标的农机跨区紧急调配模型,提出基于两阶段的农机紧急调配算法(Agricultural Machinery Emergency Algorithm based on Two Stages,TSEA)。首先按照基于距离的分区策略对大规模农田进行分区,接着采用改进的遗传算法分别对各农田分区进行农机紧急作业调配。为验证算法的有效性,主要从紧急任务的粮食损失值、算法运行时间等方面将TSEA算法与GA、SA算法进行比较,试验结果表明,TSEA算法得到的紧急调度方案优于其他两种算法。为验证本文分区策略的有效性,分别采用TSEA算法和不分区的紧急调配算法从粮食损失值、算法运行时间等方面进行比较,验证分区策略的有效性。多组试验结果表明该文提出的策略和算法对于解决大规模农田的农机跨区紧急调配问题更有效,可为农机管理部门提供解决方案。

超大规模MIMO阵列可视区域空间分布数据集

可视区域(VR)信息可用于降低超大规模多输入多输出(XL-MIMO)系统传输设计复杂度,但现有理论分析与传输设计多基于简化的VR统计分布模型。为评估分析XL-MIMO在实际物理传播场景中的性能,该文公开了XL-MIMO阵列VR空间分布数据集,其由环境参数设置、射线追踪仿真、天线场强数据预处理和VR判定准则等步骤构建。该数据集针对典型城区无线传播场景,建立了用户位置采样与场强数据、VR数据之间的关联,总数据条目数量达上亿级。进一步对其中VR形态、VR分布进行了可视化展示与分析,并以基于VR的XL-MIMO用户接入协议为例,利用该数据集对其在真实传播场景中的性能进行了仿真,为该数据集的应用提供了典型样例。

长三角一体化背景下沪蚌公立医院跨区域合作探索与实践

在长三角卫生健康一体化建设的背景下,同济大学附属第十人民医院与蚌埠市卫生健康委员会开展院地跨区域合作,整体帮扶蚌埠市3家市属公立综合性医院发展。详细阐述了在选派管理团队、确定合作目标任务、输出管理理念、推动合作医院高质量发展等方面的主要做法及所取得的初步成效。研究发现,大型公立医院优质医疗资源下沉,有组织、有计划地“组团式”帮扶地市级城市公立医院,有助于实现医疗资源均衡化。

Flow resistance in the channel-bar landscape of large alluvial rivers

Accurate approaches for estimating flow resistance in large alluvial rivers are fundamental for simulating discharge,sediment transport,and flood routing.However,methods for estimating riverbed resistance and additional resistance in the channel-bar landscapes remain poorly investigated.In this study,we used in situ river bathymetry,sediment,and hydraulic data from the Shashi Reach in the Yangtze River to develop a semi-empirical approach for calculating flow resistance.Our method quantitatively separates flow resistance into riverbed resistance and additional resistance and shows high accuracy in terms of deviation ratio(~20%),root-mean-square error(~0.008),and geometric standard deviation(~3).Additional resistance plays a dominant role under low-flow conditions but a secondary role under high flows,primarily due to the reduction in momentum exchange in channel-bar regions as discharge increases.Riverbed resistance first decreases and then increases,which might be attributed to bedform changes in the lower and transitional flow regimes as flow velocity increases.Overall,our findings further the understanding of dynamic changes in flow resistance in the channel-bar landscapes of large river systems and have important implications for riverine ecology and flood management.