早期成岩过程中铁元素地球化学循环研究进展

铁是海洋沉积物中重要的氧化还原敏感性元素之一,是早期成岩过程中地球化学循环变化的重要动力因素。早期成岩过程中,表层沉积物中铁氧化物的赋存形态主要可分无定形(弱晶型)铁氧化物和晶型铁氧化物,且前者的含量主要决定着沉积物中铁氧化物的还原活性;铁氧化物可以通过与硫酸盐还原产生的硫化物反应进行还原,还能在铁还原菌的参与下被表层沉积物中的有机质还原,沉积物中活性铁含量、有机质含量、沉积速率、植物根系导氧作用及底栖生物的扰动均能对铁还原率造成影响。早期成岩过程中可以形成黄铁矿,形成机理主要有:1)沉积物中先前形成的硫复铁矿(Fe_3S_4)等前体物质通过加硫反应形成;2)硫过饱和的球粒胶体通过脱水、成核、结晶以及聚合作用而成单个草莓状黄铁矿或初始自行黄铁矿微晶成核、生长、聚集、固化的小型黄铁矿微球团并入更大的胶体状黄铁矿结核、草莓状黄铁矿分组,从而形成黄铁矿集合体;黄铁矿化度(DOP)可作为区分古海洋氧化还原环境的指标。对铁同位素的研究表明,异化还原作用(DIR)过程中产生的铁同位素值偏低;页岩中黄铁矿的铁同位素在2.3Ga附近发生的突变反映了第一次大气氧气增高事件。磁学参数对铁相变化具有良好的反应,环境磁学在早期成岩过程研究中的应用,有助于快速划分铁还原带、研究环境中重金属循环行为。     

基于DEM 的数字降水径流模型在黄河小花间的应用

DEM是目前用于流域地形分析的主要数据，在流域地形分析及水质构建等方面形成了比较成熟的算法，基于DEM的水文模拟技术的应用给传统的水文模拟方法带来了根本性的变化，基于栅格型DEM，应用最新引进的WMS专业水文处理软件，结合Arc/info、Areview地理信息系统工具，以黄河小花间（小浪底-花园口区间）卢氏以上流域作为研究区，进行了数字降水径流模型的应用研究。     

Simulation of astronomical solar radiation over Yellow River Basin based on DEM

Based on the developed distributed model for calculating astronomical solar radiation (ASR), monthly ASR with a resolution of 1 km×1 km for the rugged terrains of Yellow River Basin was calculated, with DEM data as the general characterization of terrain. This model gives an all-sided consideration on factors that influence the ASR. Results suggest that (1) Annual ASR has a progressive decrease trend from south to north; (2) the magnitude order of seasonal ASR is: summer>spring>autumn>winter; (3) topographical factors have robust effect on the spatial distribution of ASR, particularly in winter when a lower sun elevation angle exists; (4) the ASR of slopes with a sunny exposure is generally 2 or 3 times that of slopes with a shading exposure and the extreme difference of ASR for different terrains is over 10 times in January; (5) the spatial differences of ASR are relatively small in summer when a higher sun elevation angle exists and the extreme difference of ASR for different terrains is only 16% in July; and (6) the sequence of topographical influence strength is: winter>autumn>spring>summer.     

青海省生态环境监测信息编报与数据库管理系统

根据青海省生态环境监测业务工作的实际 ,参照全国天气监测网数据编报、发报、存储、分析、加工服务产品的工作流程 ,充分利用现代数据库管理技术、通信网络技术、多媒体技术和Web技术 ,在全省气象通信网和局域网的环境下 ,对全省生态环境监测信息资料进行有效的组织和管理。实现了生态环境监测信息自动编报、采集、实时传输、综合分析处理、服务支持等功能。     

Risk decision-making model for reservoir floodwater resources utilization

Floodwater resources utilization (FRU) can alleviate the shortage of water resources, but there are risks. To safely and efficiently utilize the floodwater resources, it is necessary to study the risk of reservoir FRU. In this paper, the risk rate of exceeding the design flood water level and the risk rate of exceeding safety discharge are estimated. Based on the principle of the minimum risk and the maximum benefit of FRU, a multi-objective risk decision-making model for FRU is constructed. Probability theory and mathematical statistics method is selected to calculate the risk rate; C–D production function method and emergy analysis method is selected to calculate the risk benefit; the risk loss is related to flood inundation area and unit area loss; the multi-objective decision-making problem of the model is solved by the constraint method. Taking the Shilianghe reservoir in Jiangsu province as an example, the optimal equilibrium solution of FRU of the Shilianghe reservoir is found using the risk decision-making model, and the validity and applicability of the model are verified.     

1960-2012年内蒙古寒潮时空变化特征(英文)

In this study, we analyzed the spatiotemporal variation of cold surges in Inner Mongolia between 1960 and 2012 and their possible driving factors using daily minimum temperature data from 121 meteorological stations in Inner Mongolia and the surrounding areas. These data were analyzed utilizing a piecewise regression model, a Sen+MannKendall model, and a correlation analysis. Results demonstrated that(1) the frequency of single-station cold surges decreased in Inner Mongolia during the study period, with a linear tendency of –0.5 times/10a(–2.4 to 1.2 times/10a). Prior to 1991, a significant decreasing trend of –1.1 times/10a(–3.3 to 2.5 times/10a) was detected, while an increasing trend of 0.45 times/10a(–4.4 to 4.2 times/10a) was found after 1991. On a seasonal scale, the trend in spring cold surges was consistent with annual values, and the most obvious change in cold surges occurred during spring. Monthly cold surge frequency displayed a bimodal structure, and November witnessed the highest incidence of cold surge.(2) Spatially, the high incidence of cold surge is mainly observed in the northern and central parts of Inner Mongolia, with a higher occurrence observed in the northern than in the central part. Inter-decadal characteristic also revealed that high frequency and low frequency regions presented decreasing and increasing trends, respectively, between 1960 and 1990. High frequency regions expanded after the 1990 s, and regions exhibiting high cold surge frequency were mainly distributed in Tulihe, Xiao’ergou, and Xi Ujimqin Banner.(3) On an annual scale, the cold surge was dominated by AO, NAO, CA, APVII, and CQ. However, seasonal differences in the driving forces of cold surges were detected. Winter cold surges were significantly correlated with AO, NAO, SHI, CA, TPI, APVII, CW, and IZ, indicating they were caused by multiple factors. Autumn cold surges were mainly affected by CA and IM, while spring cold surges were significantly correlated with CA and APVII.     

Discovery of Liquid Cryptoexplosive Breccia in the Pulang Porphyry Copper Deposit of Yunnan Province and its Prospecting Significance

<正>The Pulang porphyry copper deposit,located in the Gezan tectonic-magmatic arc and south of the Yidun island arc,southwest of Sanjiang metallogenic belt in Yunnan province,is a super-large porphyry copper deposit.During recent decades,the Pulang deposit has attracted wide attention among geologists both at home and abroad.Many previous researches have discussed its     

小型文物摄影测量三维建模主体对象识别

通过拍照进行三维建模的摄影测量技术是文物数字化的重要手段,然而,在摄影测量文物三维重建过程中,文物所在的场景背景也同时参与计算和建模,需要设法删除,以获得文物单体模型。针对上述问题,本文提出一种小型文物三维模型主体对象识别方法,能够自动删除文物摄影测量三维模型的背景数据。该方法分别利用深度学习网络Mask R-CNN和改进为自动获得初值的One Cut进行文物图像前景内容识别,再融合两种方法的识别结果进行文物图像主体对象分割,最后以二维图像分割结果为依据,逐三角形识别三维模型主体对象,并运用多视角约束法优化识别精度。实验表明,本文方法能够获得小型文物单体化三维模型,无需人工干预且精度较高。     

基于历史卫星遥感影像对城区空间形态演变的研究——以山东省潍坊市为例

基于潍坊市近50年来历史遥感影像,通过人机结合的方式,对历史影像进行中心城区范围提取,并开展面积变化、扩张速度和扩张强度、紧凑度、分形维数、重心迁移等相关指数的统计分析,发现潍坊市中心城区扩张的历史演变规律。通过提取水系、道路等城市发展相关要素,分析对其历史变化情况进行专题分析,以此为城市发展和规划提供数据和决策支撑。研究发现,潍坊市中心城区的空间形态演变规律初期向东侧发展,与寒亭区、坊子区形成三角状星型结构。后发展形成东西一体相连的单中心城区结构,最终形成潍坊市中心城区东西、南北十字结构。     

Geochronology,sediment provenance,and fossil emplacement at Sumidouro Cave,a classic late Pleistocene/early Holocene Paleoanthropological site in eastern Brazil

Peter Wilhelm Lund's (1845a) heavily debated suggestion of a contemporaneity between Paleo‐Indians and extinct Pleistocene fauna at Sumidouro Cave was re‐examined through detailed sedimentological and geochronological analyses of sediment and both human and faunal remains. Sources of the cave's sediment include both entrances as well as ceiling fissures. Non‐human fossils, on the other hand, were probably carried by floodwater through the once more‐spacious swallet entrance. Seasonal flooding reworked and mixed these two highly asynchronous assemblages. U‐series and radiocarbon ages indicate that there are at least two distinct episodes of sediment input in the cave, at ˜240,000 yr B.P. and ˜8000 yr B.P. Human remains represent a later emplacement event, probably at ˜8400 cal yr B.P. Although the human remains are of considerable age, the cave's complex stratigraphy, flooding dynamics, and extensive removal of the cave's filling during earlier excavations do not allow the determination of an unequivocal co‐existence between Paleo‐Indians and extinct megafauna at the site. © 2005 Wiley Periodicals, Inc.