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1.
水力压裂是低渗油气藏提高产量的有效措施之一,然而影响水力压裂选井选层的因素繁多而复杂,并且其本身在一定程度上具有模糊性,很难运用常规方法进行量化研究.这里利用模糊层析分析法确定各影响因素的权系数,并对灰色关联系数加权得到灰色关联度,在此基础上建立模糊层次分析法和灰色关联度相结合的综合评价模型.该模型考虑了两种数学方法的优势,并将其结合起来,达到扬长避短的效果,对压裂选井选层具有指导意义.  相似文献   

2.
为了建立更好的岩体质量分级系统,改进传统岩体质量分级方法以及其它数学评价方法,结合红岩水库通航隧洞现场工程地质条件,建立了可拓学理论岩体质量分级评价的物元模型,并采用灰色关联度方法改进可拓学理论中求取各评价指标权重主客观因素考虑不充分的缺点.研究结果表明,采用灰色关联度法充分考虑了岩体质量评价的主客观因素,计算出的各指...  相似文献   

3.
基于灰色关联度模型的区域滑坡敏感性评价   总被引:2,自引:0,他引:2       下载免费PDF全文
数理统计和机器学习模型如支持向量机(support vector machine,SVM)等,在区域滑坡敏感性评价中得到广泛的应用.但这些模型的建模过程往往较复杂,如在对机器学习进行训练和测试时难以选取合理的非滑坡栅格单元,而且有较多的模型参数需要确定.为提高滑坡敏感性评价建模的效率和精度,提出基于灰色关联度的敏感性评价模型.灰色关联度模型能有效计算各比较样本与参考样本之间的定量的关联度,具有建模过程简洁和评价精度高的优点,该模型目前在区域滑坡敏感性评价中的应用还没有引起研究人员的足够关注且有待进一步拓展.拟将灰色关联度模型用于浙江省飞云江流域南田—雅梅图幅(南田地区)的滑坡敏感性评价,并将得到的评价结果与SVM模型的敏感性评价结果作对比分析.结果显示,灰色关联度模型在高和极高敏感区的滑坡预测精度优于SVM模型,而在中等敏感区的滑坡预测精度略低于SVM模型;整体而言,灰色关联度模型对整个南田地区滑坡敏感性分布的预测精度略高于SVM模型.对两个模型建模过程的对比结果显示,灰色关联度模型建模较简单,具有比SVM模型更高的建模效率,为滑坡敏感性评价提供了一种新思路.  相似文献   

4.
煤层气含量是评价煤储层的一个重要参数。本文将灰色系统用于煤层测井曲线,利用改进的斜率关联度法,分析了对煤层气含量敏感的测井曲线序列;对正关联相关的测井曲线序列利用灰色多变量静态模型GM(0,N)预测煤层气含量。并以沁水煤田为例,将预测结果与多元回归模型分析的结果进行比较并对本文方法模型的实用性进行研究分析。结果表明,应用改进的斜率关联度对测井曲线与煤层气含量进行灰色关联分析能更充分开发测井曲线与煤层气含量的关系;用GM(0,N)模型预测煤层气含量比多元回归模型预测的结果更精确,且本文模型更为强健,可在样本数据相对较少的情况下有效预测煤层气含量曲线,结果可信度高,具有实际应用价值。  相似文献   

5.
煤层含气量是一个受多因素影响的反映煤层含气性的定量指标。以晋城矿区为例,根据煤层气地质基本理论,利用改进的斜率关联度法,分析了煤层气含量的影响因素;进而,由灰色多变量静态模型GM(0,N)预测了煤层气含量,并与多元回归分析的结果进行比较。结果表明,用改进斜率关联度进行灰色关联分析所确定的煤层气含量的主要影响因素是可信的;由GM(0,N)模型预测煤层含气量所需样本数据少,原理简单,计算方便,且预测精度较高。   相似文献   

6.
本文首先介绍了灰色系统理论中灰色关联度分析方法的基本原理,然后以实测电测深找水资料为基础,系统地阐述了在灰色系统理论中,灰色关联度分析方法在电测深找水资料数据处理中的应用  相似文献   

7.
面向高精度地质灾害易发性评价研究中,历史灾害样本数据少而造成的预测准确度低等问题,本文提出基于灰色关联度与层次分析法耦合的地质灾害易发性评价模型。本文以浙江省丽水市云和县崇头镇为工程背景,结合该地区致灾机理,利用现场调查和遥感解释等手段,获取9项地质灾害评价因子。分析了9项评价因子与历史灾害点的关联度,分别以关联度数值、关联度数值指数标度和关联度排名构建了层次分析法的3种判别矩阵,建立了3种类型的灰色关联度与层次分析法耦合评价模型(G-A1、G-A2和G-A3),以及单独灰色关联度评价模型(G),最后对评价结果进行了可靠性分析。结果表明:(1)在易发性综合指数分布方面,耦合模型G-A1和单独模型G较为合理;(2)在预测准确度方面,耦合模型G-A1的ROC曲线AUC指标最大;(3)在易发性分区合理性方面,耦合模型G-A1的高易发区域面积所占比例最小、高易发性强度指数最大,工程适用性强。最终,推荐耦合模型G-A1作为丽水市云和县崇头镇地质灾害易发性评价模型。本文研究成果对浙西南地区地质灾害易发性评价具有重要参考价值,为高精度地质灾害评价和防控工作提供有效的耦合评价模型。  相似文献   

8.
灰色评价熵模型在含油面积评价中的应用   总被引:2,自引:0,他引:2  
针对目前灰色关联分析方法在评价岩性、物性、含油性、含油面积等地质模型中有时存在评价结果分辨率不高的问题,基于信息论中Jaynes最大信息熵原理和灰色关联度的定义,构造目标函数,运用拉格朗日乘数法,建立了一种新的灰色精细评价模型。结合实例说明了模型的具体应用,并与原灰色关联分析方法进行了对比,结果基本一致,而且明显提高了分辨率。该模型数学推导严谨,可靠性高,具有较高的灵敏度。   相似文献   

9.
将改进后的灰色关联法应用于赤峰市宁城县水源地地下水水质评价中,通过对检测数据处理,决策矩阵构建,熵权改进,关联度计算等步骤,综合评价了6个取样点水质类别,并与F值评分法评价结果对比分析。结果表明:采用改进的灰色关联法考虑了水质分级界线的过渡性和不同的评价指标对地下水水质权重的影响,评价结果比F值评分法更具有综合性。  相似文献   

10.
李玉葆 《物探与化探》1992,16(4):316-319
灰色关联度分析法,是灰色系统理论中较为有效的分析方法之一,是邓聚龙教授1982年提出的。目前,在水文地质研究中已得到广泛应用。我们根据水化学分析结果,运用灰色关联度分析方法,成功地求解了峰峰三矿井下突水点的奥灰水和大青  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

13.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

14.
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931.  相似文献   

15.
16.
PALEONTOLOGY     
正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.)  相似文献   

17.
正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.)  相似文献   

18.
正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.)  相似文献   

19.
PETROLOGY     
正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus.,  相似文献   

20.
正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an  相似文献   

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