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数字高程模型（DEM）包含的信息常作为重要的水文水动力研究基础数据,但是由于公共源DEM数据精度不能完整表达河床地形,所以无法应用于河流泛洪分析等研究工作。因此,本研究开展了基于DEM数据构建数字河床的工作,首先对提取的纵向河网高程数据引入了强局部加权回归算法进行平滑处理以消除畸点;然后以河面要素文件为掩膜,采用反距离加权方法进行横向的空间插值得到3D数字化河面;最后结合河面高程与河深数据完成河床的整体构建。本研究以SRTM DEM为数据地形基础,以位于我国吉林省永吉县境内的温德河为研究实例,对其下游局部区域内的河段重构了矩形、梯形和V型 3种河床断面数字地形。为评价重构数据的合理性,分别对所得到的数字河面进行等值线分析;对河床构建前后DEM水文分析提取的河网进行河道偏移量计算;对构建的地形数据进行河流水动力模拟应用分析,结果表明：① 应用反距离加权插值可以很好地实现河网高程向河面高程的横向延展;② 基于河床重构DEM数据的水文分析误差得到了很好地消除;③ 本研究的重构数据在河流分析中具有较好地应用性和可靠性。 相似文献
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平衡剖面的制作流程及其地质意义 总被引：9，自引：0，他引：9
平衡剖面技术是地质思维和计算机技术的结晶,使对断层构造的研究提高到定量阶段,其依据是在垂直构造走向的剖面上,地层长度和面积(2D)或体积(3D)是均衡的。在此原理基础上利用数学手段对盆地的构造发育史进行正演和反演模拟,直观地再现地下构造的原始几何形态,迅速提供地震剖面的构造解释方案,并对解释结果进行检验(不平衡的剖面其解释一般有问题),为深刻认识构造发育史、分析油气运移及聚集规律提供依据,提高了工作效率。其结果也为盆地模拟、油藏模拟、定量计算构造伸缩量等地质研究打下了坚实的基础[1]。 相似文献
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被古河流冲刷的煤层范围直接影响着可采储量及采区设计,而煤层中充填的河道砂岩的含水性又影响着采煤安全。所以,现代三维地震勘探任务中经常有探测煤层异常体及古河床冲刷范围的项目。因此,有必要对煤层冲刷的地质特点及地震资料解释方法进行研究。根据煤系及河流沉积规律,通过钻孔资料做煤层顶板岩性分布趋势分析图,结合地震地质模型研究,找出煤层冲刷及河流相沉积在地震反射剖面上的反映特征,利用三维地震剖面资料,煤层反射波顺层振幅切片等综合手段确定河流对煤层的冲刷范围。 相似文献
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锡林郭勒大草原的迅速沙化，已经成为我国严重的环境问题。查清其第四系沙源的沉积相和微相及其空间特征，有 助于寻找标本兼治的途径与方法。以锡林河中游的吉尔嘎郎图平地小草原为例，首 先，对典型剖面进行了分层精准观测和采样测试，把宏观沉积学研究与微观粒度参数分析相结合，在第四系栗钙土中识别出河床、堤岸和洪泛３个亚相及其所属的６个微相，建立了６种微相的粒度分布模型；然后，基于图解法的粒度参数计算和有约束点的动态聚类分析法，实现了面上大量栗钙土样品的沉积微相归类，从而快速有效地查明了沙化沙源为河流侵蚀成因，沙源来自下伏白垩系顶部的古河流－三角洲砂体。 相似文献
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三维地质空间表达可以准确揭示地质现象与过程的空间结构与分布规律。传统三维地质建模方法广泛存在着面向局部小区域、基于投影数据、表面静态建模、难以进行3D空间查询与分析、不利于时空大数据的组织与管理等缺陷。地球剖分网格以其全球全方位视角、循环递归剖分机制和有机灵活的编解码策略为解决上述问题、构建新一代数字地球平台提供了新的技术方案。本文以郑州航空港经济区为例,利用实测地质数据,基于球体测地线八叉树剖分瓦块（SGOG网格）,建立区域真三维地质模型框架,并进行空间分析。在对原始数据进行预处理的基础上,将SGOG特定剖分层次的瓦块节点与地质体外包络体特征点数据进行匹配,构建真三维地质框架;通过漏洞修补和着色渲染,建立多尺度多地层三维地质体模型;在此基础上,进行真三维地质空间分析,包括地质体真三维剖面、数字钻孔以及几何特征参数计算。实验结果表明：本文的建模方法,不但结构简单,操作方便,适用于复杂不规则的地质体,而且可以利用SGOG瓦块的多尺度特性,灵活实现精度与尺度的自适应表达,方便进行多角度真三维空间分析。地球剖分网格是数字地球发展的必然趋势。 相似文献
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东准噶尔顿巴斯套金矿床L8号矿体为区内主矿体之一,对其开展钻孔原生晕测量工作并建立正确的找矿模型,能够为矿区深部及外围找矿预测提供依据。选取0线、8线、7线及11线等对L8号矿体控制程度较高的勘探线剖面为研究对象,对剖面上揭穿该矿体的钻孔进行了系统采样和分析。结果表明,0线、8线及7线、11线原生晕轴向分带系列分别为Mo-Cu-Au-As-SbAg-Zn-Hg-Co-Pb和Hg-Zn-Mo-As-Au-Ag-Pb-Cu-Co-Sb。建立了L8号矿体的原生晕叠加模型,认为矿体在7线和11线、0线和8线都有一定程度的向下延伸趋势,但在0线和8线的延伸程度比7线和11线差,据此建议后期找矿工作应在7线、11线800m以下标高进行。上述认识得到了后期工程的验证。 相似文献
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黄河每年有8×108～10×108t泥沙进入河口地区。由于黄河的受水盆地浅,区域上又位于构造强烈沉降区,进入河口地区的泥沙约有80%淤积在陆上及滨海地区,逐步形成了现代的黄河三角洲。通过RS与GIS综合对比和地质成因分析,可揭示整个三角洲在河流动力和海洋动力综合作用下的快速淤进、蚀退,河床抬高和尾闾改道等一系列演变,其中又以海岸带的演变最为明显。近几年,受黄河来水来沙量减少和人为加固堤坝等因素影响,河口地区造陆速度减缓,其他地区海岸带蚀退变慢,河床进一步抬高,整个三角洲基本处于淤蚀平衡状态。 相似文献
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胜利油田开采底水特征高含水油层的水平井数量多,其中油层向水平井非均衡供液现象普遍。为评价此类水平井产液剖面均衡性,量化其生产动态改善潜力,定义了产液剖面基尼系数GN,并结合现场案例介绍其计算方法,随后统计胜利油田60口样本井,分析GN对见水时间tRL和底水突破前累积产油量QRL的影响,最后据此对GN分级。计算和分析结果表明:GN可以整体表征实际非均衡产液剖面偏离理想均衡产液剖面的程度,通常取值0~1之间,数值越大,均衡性越差;划分GN>0.1为产液剖面不均衡,其样本井数54口,占比90%,以理想均衡产液状态为基准,tRL和QRL分别至少有100%和69.5%的提升潜力。 相似文献
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在蒙古中部106°E附近布设一条南北走向的重力剖面,首次获得该地区精确的实测重力值,经过数据预处理和改正计算,得到剖面重力异常结果。分析表明,剖面自由空气异常和地形有很强的相关性|剖面布格重力异常变化总体较为平缓,只在戈壁-阿尔泰-曼达尔戈壁加里东区带(GAB)和哈拉加里东区带（HRB）附近发生相对较快的变化,推测这两个区域可能存在较明显的深部构造变化|在蒙古-鄂霍兹克造山带附近,并未发现与板块缝合带相对应的重力异常变化|剖面均衡重力异常以负值为主,多数地区地壳未达到重力均衡状态,剖面附近地震活动和均衡重力异常之间的关系与中国南北地震带北段相关研究结果类似。 相似文献
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The erosion mechanisms of abandoned coastal section are understood detailedly by flume experiment, which play an important
role to the offshore engineering facilities. A movable-bed physical model has been used to investigate the coastal erosion
of an abandoned section of the Huanghe (Yellow) River Delta. The theory of physical scale models is discussed and a method
for constructing the representative seabed section is developed. The results indicate that during the period initially after
the abandonment of the delta the entire bed experienced rapid erosion because the seabed was steep and prone to liquefaction
that resulted from storm wave action. After this initial period, a balance of erosion and accretion was established, and the
beach profile equilibrated with a point of balance present on the profile. The experimental results indicate that the volume
of deposition was about half that of the erosion. Wave action may also induce significant stratal changes through its interaction
with the soft seabed. The major morphological features developed in the model delta section were found to be qualitatively
comparable with those observed in the prototype. A distorted modeling law that maintains the similarity of the modeled and
prototype equilibrium beach profiles is proposed. Experimental results show that the distorted modeling is able to reproduce
the beach-face slope in nature, and the model also successfully reproduced three historical evolutionary stages of erosion. 相似文献
12.
MECHANISM AND EFFECT OF CHANNEL EVOLUTION AT ESTUARY OF WEIHE RIVER TO HUANGHE RIVER 总被引：2，自引：0，他引：2
LI Jing-yi SHI Chang-wei XU Xi-bao FU Zhi-jun 《中国地理科学(英文版)》2006,16(2):122-126
1INTRODUCTION Physiognomycharacteristicofawatershedisasymbolof ground erosion and incision, and it has been one of the most important factors influencing soil erosion and sedi- ment in the drainage area. Therefore physiognomy char- acteristic of the watershed and its influences on hydro- logical bed load have been one important focus in the watershed research both domestic and abroad (SCHUMM, 1977; QIAN et al., 1987) since the classical study by Horton in 1942 (HORTON, 1954). In rec… 相似文献
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According to the analysis of grain size, mineral composition and inclusion in quartz grain of the suspended and bed load sampled
from the Changjiang (Yangtze) River and the Huanghe (Yellow) River, the authors reveal the differentiation of loads between
the two rivers. In the Huanghe River the size of suspended load is coarser than that in the Changjiang River, while the bed
load is on the contrary. Through heavy mineral analysis, the biotite content of the Huanghe River loads is much higher than
that of the Changjiang River, and the monomorillonite content of the former is about two times higher than the latter. All
those may be attributed to the effects of different material sources and hydraulic conditions on load. The analysis of inclusion
in quartz grain definitely illustrates the environmental difference of material sources between the two rivers. In the meantime,
it provides a new method in seeking source of river load.
Subsidized by the National Natural Science Foundation. This paper is attributed to careful guidance from Prof. Wang Ying &
Prof. Shi Yunliang. 相似文献
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Ｉ．ＧＲＡＩＮＳＩＺＥＯＦＬＯＡＤ１．ＧｒａｉｎＳｉｚｅｏｆＬｏａｄｆｒｏｍｔｈｅＨｕａｎｇｈｅＲｉｖｅｒＴｈｅｓｕｓｐｅｎｄｅｄｌｏａｄｓａｍｐｌｅｄｆｒｏｍｔｈｅＨｕａｎｇｈｅＲｉｖｅｒｍａｉｎｌｙｃｏｍｐｒｉｓｅｓｓｉｌｔｗｈｏｓｅｃｏｎｔｅｎ... 相似文献
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黄河中游黄土高原区河川基流特点及变化分析 总被引：2，自引：0，他引：2
由于气候变化和人类活动的影响。黄土高原河川基流呈显著下降趋势。对黄河径流量减少产生一定影响。采用日流量过程线切割法计算了河龙区间黄土高原主要支流的基流量。结合地形地貌、水文地质条件，分析了不同地貌类型支流基流的特点，初步分析了影响基流变化的各种因素。认为河龙区间基流变化对黄河水资源影响较大。 相似文献
16.
Based on the data from gauging stations,the changes in water discharge and sediment load of the Huanghe (Yellow)River were analyzed by using the empirical mode decomposition(EMD)method.The results show that the periodic oscillation of water discharge and sediment load of the Huanghe River occurs at the interannual,decadal,and multi-decadal scales,caused by the periodic oscillations of precipitation,and El Nio/Southern Oscillation(ENSO)affects water discharge by influencing precipitation distribution and contributes to periodic varations in precipitation and water discharge at interannual timescale.The water discharge and sediment load of the Huanghe River have decreased since the 1960s under the influence of precipitation and huamn activities,and human activities attribute more than precipitation to the reduction in the water discharge and sediment load,furthermore,water abstraction and water-soil conservation practices are the main causes of the decrease in water discharge and sediment load,respectively.The reduction in sediment load has directly impacted on the lower reaches of the Huanghe River and the river delta, causing considerable erosion of the river channel in the lower reaches since the 1970s along with River Delta changing siltation into erosion around 2000. 相似文献
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INTRODUCTIONTidalchannelsareimportantgeomorphologicunitsalongsiltcoasts.Theyhaveanevidentfunc tionfortidalflatbecausetheyareassociatedwithitsrapidbayheadwarderosionandlateralswing ing.Thetidalchannelsdevelopalongthecoastandplayanimportantroleinseaandlandinterac tion .Manyscientistsresearchedthetidalchannels (Bayliss Smith ,1 978;Shao ,1 988;Zhang ,1 995) .TheScientificandTechnicalCommitteeofShandongProvince (1 991 )investigatedthecoastoftheHuanghe (Yellow)RiverDeltaandresearchedtheti… 相似文献
18.
Impact of the water-sediment regulation and a rainstorm on nutrient transport in the Huanghe River 总被引：4，自引：0，他引：4
Dissolved nutrient concentration in the Huanghe(Yellow) River at Lijin was monitored during a water-sediment regulation period and a subsequent rainstorm from 14 June to 19 July, 2005. This study provides detailed information on nutrient concentrations in the Huanghe River during the water-sediment regulation and rainstorm periods, and is of signifi cance for the downstream area of the Huanghe River and the Bohai Sea. The average concentrations of nitrate, nitrite and ammonia were 304.7 μmol/L, 0.19 μmol/L, and 1.10 μmol/L, respectively, while the average concentrations of dissolved inorganic phosphorus(DIP) and dissolved silicate(DSi) were 0.23 μmol/L and 122.9 μmol/L, respectively. Nutrient concentrations during the water-sediment regulation period were mainly infl uenced by the dilution effect, fl oodplain effect and sediment resuspension while dilution and erosion effects were the main factors during the rainstorm. The fl uxes of dissolved inorganic nitrogen(DIN), DIP and DSi during the water-sediment regulation and rainstorm periods accounted for 20.4%, 19.5%, 16.7% and 4.97%, 6.45%, 5.47% of the annual nutrient fl uxes, respectively. Discharge was the main factor infl uencing the fl uxes of nutrients during both the watersediment regulation and the rainstorm periods. 相似文献
19.
Jinqing Liu Ping Yin Yong Zhang Hongying Song Shipu Bi Zhimin Cao Shanshan Liu 《中国海洋大学学报(英文版)》2017,16(5):747-756
Detrital minerals of 137 offshore and 22 river sediment samples collected from Qingdao coastal areas have been analyzed. Four mineral assemblage provinces can be classified by Q-mode cluster analysis. Factor analysis identifies two major factors that account for the total variability in most common minerals: 1) based on the relationship of quartz, hornblende, actinolite, micas, and authigenic pyrite, 41.55% of the variability is related to sediment sources; 2) based on the relationship of epidote, garnet, sphere, and ilmenite, 23.21% can be related to strong hydrodynamic conditions that control transport and sedimentation. By comparing mineral compositions of river waters in the study area, the following four mineral provenances can be identified. The Qingdao-Laoshan nearshore area has a quartz-feldspar-epidote-hornblende-limenite-limonite-sphene assemblage, which is largely attributed to relict sediment and coastal erosion. The Jimo-Haiyang nearshore area has a quartz-feldspar-hornblende-epidote-limonite-mica-actinolite assemblage, derived largely from the Wulong River and Rushan River, and is also affected by the Huanghe River, while the Qianliyan Island area in the deeper offshore area separated by a mud belt has a similar assemblage. The Haiyang-Rushan nearshore area has a quartz-feldspar-hornblende-epidote-micas-limonite assemblage, indicating multiple sources from the Rushan River, the Wulong River, the Huanghe River, and coastal erosion. The central area, located in an eddy center, has a mica-authigenic pyrite-hornblende-quartzfeldspar assemblage, indicating multiple sources dominated by Huanghe River distal sediments. 相似文献
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渤海湾盆地碎屑物质的物源示踪研究,对于渤海湾盆地的自身演化,周缘造山带隆升和剥蚀过程,以及中国东部陆架海的物质扩散研究均具有重要意义,受到国内外学者的广泛关注,同时也存在诸多争议。钾长石是地壳中最主要的造岩矿物之一,在河流沉积物中广泛出现,在进行物源示踪研究时具有代表性。基于此,利用激光剥蚀电感耦合等离子质谱仪（LA-ICP-MS）对渤海湾盆地主要注入河流的碎屑钾长石进行了原位地球化学特征分析,结果表明,黄河干流碎屑钾长石的常量元素Na2O、Al2O3、SiO2、K2O的标准偏差与滹沱河、滦河、辽河和漳河4条河流存在差异。在钾长石常量元素Al2O3质量分数与Na2O和K2O质量分数二维散点图中,部分黄河样品的Al2O3值较之整体部分（其他4条河流和黄河样品）偏低;微量元素中Ba、Pb、Sr、Rb和Ca的质量分数占主体部分,尤其Ba、Pb、Sr、Rb的含量较高。在Ba和Sr以及Ba和Pb质量分数二维散点图中,黄河与其他4条河流明显不同。该研究结果表明,钾长石的Ba和Sr含量变化可以成为环渤海湾盆地沉积物中黄河物源示踪的特征指标。 相似文献