基于浮标观测的长江口外海流特征分析

为了揭示长江口外海域海流的特征及其季节和垂向变化规律,于2006年8月1日-2007年7月31日在长江口外海域（平均水深约46.0m）利用大型浮标进行了1年的分层海流流速流向观测。结果表明：（1）该海域海流为顺时针方向的旋转流,在垂向上流向较一致,季节变化不显著。（2）长江口外海域水平流速总体较大,夏季表层最大流速为128.5cm/s,冬季最大表层流速为105.5cm/s;垂线平均流速相近（差异<8.0 cm/s）,夏季流速最大为47.0cm/s,冬季为40.8cm/s。小潮的平均流速为26.5cm/s,大潮平均流速为小潮的2倍。（3）剖面各层流速垂向差异明显,最大流速出现在表层（春季和冬季）或次表层（夏季和秋季）,最小流速均出现在底层;各层的最大平均流速为57.9cm/s,出现在夏季的18m层。（4）垂线平均余流为7.5~11.3 cm/s,春季最强冬季最弱;春季和冬季各层余流均为东向,夏季和秋季基本为东北向或北向。（5）观测海域海流受长江冲淡水、台湾暖流、季风、潮汐等动力作用的共同制约。     

基于多尺度小波边缘检测的对流降水和闪电分析

为准确估测对流降水,提出了多尺度小波边缘检测算法,借鉴小波变换的多尺度分析和边缘检测原理,对雷达反射率数据进行处理,有效地识别出对流云回波区域,进而反演对流降水,精细化分析其和闪电的相关关系。选取了南京2009年7月6—7日的一次强雷暴降水过程中对流活动较剧烈的180 min为例,对采自南京龙王山雷达站的真实数据进行了算法识别分析,反演得到对流降水,统计6 min时间间隔内的闪电频数与同期降水进行相关分析,得到该时段中每次闪电所表征的降水量（RPF）的范围在7.47×106～4.46×107 kg,平     

High-resolution structure-from-motion models covering 160 km-long surface ruptures of the 2021 MW 7.4 Madoi earthquake in northern Qinghai-Tibetan Plateau

The 22 May 2021 M_W 7.4 Madoi, Qinghai, China earthquake presented a rare opportunity to apply the modern unmanned aerial vehicle (UAV) photography method in extreme altitude and weather conditions to image surface ruptures and near-field effects of earthquake-related surface deformations in the remote Tibet. High-resolution aerial photographs were acquired in the days immediately following the mainshock. The complex surface rupture patterns associated with this event were covered comprehensively at 3–6 cm resolution. This effort represents the first time that an earthquake rupture in the interior of the Qinghai-Tibetan Plateau has been fully and systematically captured by such high-resolution imagery, with an unprecedented level of detail, over its entire length. The dataset has proven valuable in documenting subtle and transient rupture features, such as the significant mole-tracks and opening fissures, which were ubiquitous coseismically but degraded during the subsequent summer storm season. Such high-quality imagery also helps to document with high fidelity the fractures of the surface rupture zone (supplements of this paper), the pattern related to how the faults ruptured to the ground surface, and the distribution of off-fault damage. In combination with other ground-based mapping efforts, the data will be analyzed in the following months to better understand the mechanics of earthquake rupture related to the fault zone rheology, rupture dynamics, and frictional properties along with the fault interface.     

Characteristics of daily and extreme temperature over Canada

利用重庆34个自动站1991-2015年逐小时降水资料,分别从降水比率、强降水占比、强降水频次、强降水事件、极大强降水及极端强降水阈值等方面分析了重庆时空分布特征。结果表明：（1）降水比率、强降水占比、强降水频次、强降水事件、极大强降水及极端强降水阈值在空间分布上具有一致性,高值区主要分布在东南部与西部,低值区主要位于东北部与中部。（2）降水比率、强降水占比、强降水频次及极大强降水在年变化上表现出波动起伏特征,且降水比率相对变化幅度较小,后三者表现出同相位的变化特点。在月变化上,降水比率呈双峰特征,后三者一致呈单峰特征。在日变化上,强降水高频次主要出现在03-05时,低频次主要是13-15时。（3）在强降水事件持续性上,强降水事件持续时间及其降水开始至最强降水时间的空间分布一致：高值区主要集中在东北部与东南部,而低值区主要分布在中部与西部。总体上看,持续时间越长,产生最强降水的时间越延后,且持续时间长的强降水事件主要产生在23时至次日04时。（4）第99、99.5、99.9百分位阈值与广义极值（GEV）分布函数5、10、20、50、100 a重现期阈值及极大强降水观测值在空间分布上与强降水具有一致性。

     

黑龙江北部孙吴——嘉荫盆地沉积相类型及其演化

通过对孙吴-嘉荫盆地淘淇河组、永安村组、太平林场组、鱼亮子组、乌云组和孙吴组露头剖面详细的沉积学研究,查明该盆地从淘淇河组到孙吴组发育的沉积相类型有冲积扇、辫状河、曲流河、扇三角洲、辫状河三角洲、曲流河三角洲、湖底扇和湖泊。冲积扇及扇三角洲主要发育于淘淇河组和孙吴组;辫状河及辫状河三角洲主要发育于鱼亮子组和乌云组;曲流河及曲流河三角洲主要发育于永安村组和太平林场组,各组均有湖泊相沉积发育。孙吴-嘉荫盆地从淘淇河组到乌云组,具有冲积扇-扇三角洲-湖泊→曲流河-曲流河三角洲-湖泊→辫状河-辫状河三角洲-湖泊→冲积扇-扇三角洲-湖泊的沉积演化规律,反映晚白垩-古新世构造活动性减弱,中-上新世孙吴组沉积时重又趋于活动。     

0-1整数规划在水源地开采井最优布局中的应用研究

新建水源地如何最优布井,对水源地开采运行具有重大影响。本文介绍了0-1整数规划及其求解方法,并结合一个实际问题进行说明。作者应用0-1整数规划方法建立了北京密怀顺平原区拟建水源地最优布井的地下水管理模型,采用响应矩阵法将地下水模拟模型和管理模型相耦合,运用分支-定界法求出最优井位,并将优化井位与原拟定井位的计算结果进行了对比。结果表明,0-1整数规划能很好地解决最优布井问题,对水源地规划、基坑降水、地下水人工回灌等方面都具有一定的指导意义。     

吉林省东部地区贵金属、有色金属矿床控矿因素及成矿物质来源

吉林省东部跨槽、台两大构造单元,形成了与这相应的构造样式、沉积建造和岩浆活动。产出的各种矿床受多种因素控制,成矿物质也具多源性。因此形成了不同矿种、不同成因类型、不同物质来源、受不同地质因素控制各具特点的多个成矿带。     

重庆地区下古生界页岩气聚集条件及有利区预测*

重庆地区是中国页岩气勘探开发取得突破的地区,页岩气赋存层位主要为下古生界上奥陶统五峰组—下志留统龙马溪组有机质泥页岩。依据露头、钻井岩心及测井资料,利用沉积学、有机地球化学等方法,分析研究区泥页岩沉积学特征与岩石学特征、页岩气聚集条件,并预测区内页岩气有利区。结果表明,区内暗色泥页岩厚度大,分布广,总有机碳含量大于2%,有机质类型以Ⅰ型为主,热演化程度处于高成熟—过成熟阶段,说明该区泥页岩具有很好的生烃潜力;区内页岩气层上覆厚层泥页岩与下伏岩层灰岩对页岩气具有较好的保存效果;泥页岩含气量较高,平均为1.39,cm³/t。采用综合信息叠合法,可预测研究区页岩气发育有利区位于城口—巫溪一带与石柱—涪陵—武隆—彭水—南川—綦江一带。     

三峡库区山区农业生态系统转型

The Three Gorges Reservoir Area(TGRA)is typical of an ecologically vulnerable area,comprised of rural and mountainous areas,and with high immigration.Because of its economic and ecologic importance,studying the traditional agroecosystem changes in the TGRA is key to rural development and revitalization.In this study,we apply a framework of theoretical analysis,empirical study,and trend prediction to the Caotangxi River watershed within the TGRA.Using QuickBird high-resolution remote sensing images from 2012 to 2017 to evaluate natural resources and farmers’behavior,we analyze the transition and trends in the traditional agroecosystem in mountainous areas of the TGRA at spatial scale of the man-land relationship.We find that the agroecosystem in the TGRA can be divided into four modes using 100 m interval buffer rings:high-low-low,high-low-high,low-high-low and low-low-high mode where the different modes represent the agricultural development stages in the TGRA.Furthermore,the traditional agroecosystem in TGRA,represented by system elements such as farmers and sloping farmland,is transforming to accommodate the diversification of farmer livelihoods.For example,sloping farmland,which was dominated by a production function,now has equal emphasis on ecological and economic functions.Spatially,the range of the agroecosystem transition has migrated beyond high mountain areas to flat valley areas.Generally,this study provides an overview of land use in rural areas,controls on soil and water loss in mountainous areas,and better rural living environments in the TGRA.     

南海北部中—深层环流格局下海山-阶地-峡谷沉积效应

作为研究水-岩界面物质能量交换的天然实验室,南海北缘陆坡区具有复杂的地形地貌（如凸起海山、平坦阶地、下凹峡谷等）,并发育不同类型的深水沉积体系（包括重力流滑移滑塌、浊流和底流沉积等）。基于高分辨率海底地形、地震反射资料,海水温盐深（CTD）观测资料,以及已发表的海洋沉积学及物理海洋数值模拟结果,本文针对南海北缘代表型陆坡区开展中—深层环流格局下海山-阶地-峡谷沉积效应分析。发现了尖峰陆坡区侵蚀型-海山型（环槽-丘状漂积体）和席状/无沉积型底流阶地的沉积组合,以及一统陆坡区海山相关底流沉积（环槽-丘状漂积体）-席状/无沉积型底流阶地-黏附型漂积体-陡坡滑塌/峡谷体系的沉积组合;揭示了这些典型深水沉积组合与南海中—深层环流动力格局的耦合关系。该成果对于深入了解深水沉积过程对中-深层动力格局的响应及其对于大陆边缘形态的塑造具有较好的启示意义。