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本文在原古生物化石微机鉴定系统的基础上,通过引入模糊数学、压缩特征数据编码系统和增强数据库功能,对原系统的特征数据代码、化石相似程度的判定以及数据库管理等三方面作了改进,使其不但能够进行化石鉴定,而且还能进行化石组合分析、化石系统分类以及化石定义的研究。 相似文献
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地质图形处理系统设计 总被引:5,自引:0,他引:5
介绍了地质图形计算机处理系统的系统功能、系统结构、图形数据库结构以及图形生成与编辑;讨论了在开发地质图形计算机辅助设计或绘图系统时,应如何体现专业特点,如何在数据中表达地质现象的地层和构造意义,如何在地质模型建立中融入专业人员的地质背景知识,以及怎样设计出实际有效的地质图形处理软件系统等问题。 相似文献
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我国即将完成1: 2 500 000全月球数字地质图编制,为便于成果数据存储管理和集成共享,需要建立完备合理的空间数据库。本文基于本次编图工作实践,对月球地质图空间数据库要素内容进行了全面整理和归类。月球地质图空间数据库要素包括物质要素、构造要素、其他特殊符号、注记共4个大类,在大类基础上细分为13个中类及40个小类,并据此设计了具有可扩展性的要素分类代码。空间要素采用分层的方式进行组织管理,图层名前4位为所属图幅号,第5位为比例尺代码,其后为图层英文名称的缩写。每个要素图层与一张属性表关联,对属性表所有字段的字段名称、别名、类型、能否为空、长度、小数位及单位进行了定义和规范。本文选取月表撞击坑坑物质、月海岩石、撞击断裂及高程点要素详细阐述了其属性表结构。属性表主键为“要素标识号”,用于唯一标识某一个图元,其由图幅号、比例尺代码、要素分类代码、图元顺序码四层14位层次码构成。数据库设计遵循可扩展原则,特定区域或其他比例尺的月球地质图空间数据库建设也可参照执行,本文以月球冯·卡门撞击坑及邻区地质图为例进行了空间数据库设计。科学合理的数据库设计是数据库建设的前提,将为编图成果存储管理、集成共享与国际合作提供重要支撑。 相似文献
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介绍了适用于油气资源评价的基于GIS的菜数据库,对建立该图形数据库的基本思想,如空间数据和非空间数据的对应关系和数据链接问题,图形数据库数据、信息类别以及数据库的结构等进行了讨论。 相似文献
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本文阐述了由我局开发的基于B/S模式的网站动态信息发布系统,描述了系统的基本模块和功能。此系统利用JavaBean组件技术集成程序代码,采用JDBC进行Web数据库访问,并给出了系统实现的一些关键性的代码。 相似文献
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基于GIS的滑坡空间数据库研究--以云南小江流域为例 总被引:8,自引:1,他引:7
滑坡作为一种典型的地质灾害现象,有其特有的属性特征、方法及事件特征。在面向对象的GIS中,滑坡因素空间数据库是描述滑坡对象的主要指标系统。滑坡因素空间数据库包括滑坡因子数据库和滑坡分布数据库。滑坡因子主要分为静力因子和动力因子。静力因子决定了滑坡空间分布特征及规律。动力因子与新滑坡的变形失稳及老滑坡的再次活动密切相关。通过航片解译和现场勘查等工作建立的滑坡因素空间分布数据库是建立滑坡GIS分析模型的重要环节。滑坡因子数据库与空间分布数据库不仅包括属性数据库,而且包括图形数据库。它们的建立需要经过概念模式设计,逻辑设计,物理设计3个重要的步骤。云南小江流域是我国西南地区典型的滑坡等地质灾害多发区,以其为例对滑坡空间数据库的设计与创建过程进行了详细的说明。 相似文献
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基于GIS技术的矿产资源规划管理信息系统 总被引:5,自引:0,他引:5
结合正式颁布实施第一轮辽宁省矿产资源规划,论述了本系统通过对GIS功能和数据库功能的组合和集成,实现了分布式远程数据库管理,图形、文档指标3类数据的互动式管理,并支持空间数据的统计和分析,同时还可进行规划项目实施的远程办理,为矿产资源规划管理部门提供一种全新的宏观管理和决策支持的手段和依据. 相似文献
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Rock cut stability assessment in mountainous regions 总被引:1,自引:0,他引:1
Gorka Uribe-Etxebarria Tomás Morales Jesús A. Uriarte Valentín Ibarra 《Environmental Geology》2005,48(8):1002-1013
Ensuring stability of rock slopes is an essential requirement in the progress of our societies today. Rock determined to be
loose or with potential for failure must be removed or restrained in some way. In our work, after doing an inventory of the
instabilities that occurred in the last 5 years in the Basque Country, we analyse the different factors, in slope stability.
The potential for failure is evaluated for different classes of rock mass, characterized previously by their geomechanical
properties. The characterization of potential risk of each one is undertaken by considering 10 parameters that define the
nature of mass rock, relative orientation and morphological features of the slope (interaction rock massif-slope) and infrastructure
features (interaction rock massif-slope-infrastructure). Each of these parameters is evaluated separately and a Risk Factor
(RF) is determined. The RF reaches a maximum value of 10,000 and allows to differentiate four categories of slopes; each category
has its own priority. Rock mass characteristics also determine the potential damage from instability and the associated correction
measures. The systematic evaluation of instabilities must allow establishing a priority in the correction measures and thus
optimise the available economic resources. 相似文献
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This paper presents experimental data for the trapped noble gas contents in a variety of shales and related samples. These data, along with those previously available, indicate that the normal sedimentary rock pattern is one of progressive enrichment of the heavier gases in comparison with the proportions in air, from which sedimentary rock gases were presumably acquired. Within this normal pattern, however, variations considerably beyond an order of magnitude characterize both abundance and composition, so that multiple processes appear to be necessary to account for trapping of noble gases in sedimentary rocks. Relative to the normal pattern a number of cases of anomalous Ne enhancement occur. This unexplained phenomenon, previously thought to be exotic, must now be considered unexceptional.Noble gases in air occur in approximately the ‘planetary’ proportions characteristic of meteorites, except for more than an order of magnitude deficiency of Xe. It is commonly held that atmospheric noble gases are indeed planetary, the Xe deficiency in air being made up by the inventory in sedimentary rocks. We consider that while this hypothesis cannot be proved false the available data do not support it. At least equal weight should be given to the alternatives: either that (preferentially) Xe has failed ever to become part of the atmosphere or that the total terrestrial noble gas inventory is simply not planetary. 相似文献
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Failure mechanisms and triggering factors in calcareous cliffs of the Subalpine Ranges (French Alps) 总被引:3,自引:0,他引:3
In order to enhance the detection of prospective rock falls in calcareous cliffs, 25 rock falls have been described in a more detailed way than for an inventory. They are representative of middle size rock falls (10 to 100,000 m3) occurring in the French Subalpine Ranges, at an elevation between 200 m and 2000 m. Structural conditions of the rock masses, morphology of the initial cliff surface and the scar, possible failure mechanisms and processes have been studied. Typical failure configurations have been identified, based on the attitude of the failure surface, in relation to the bedding planes and the cliff surface. Irregular cliff morphology appears to be another important susceptibility factor. In most cases, the classical comparison of the average planes of the main joint sets with the average plane of the slope could not define the potentially unstable masses. Rather, those ones are due to joint planes that deviate from their mean set plane or to irregularities of the cliff surface. The proposed investigation method to detect prospective rock falls mainly consists in observing stereoscopic aerial photographs in order to look for critical configurations. Once a critical mass has been detected, its failure probability for a period of the order of one century must be evaluated (or its life expectancy). The main factor to consider for this purpose appears to be the proportion of rock bridges in the potential failure surface.
The triggering factors of rock falls in our study area have been investigated, by analysing an inventory of 46 rock falls. Statistical tests have been carried out to study the relation between rock falls and daily rainfall, freeze–thaw cycles or earthquakes. A good correlation has been obtained with freeze–thaw cycles, a slight correlation with rainfall and no correlation with earthquakes. This suggests that ice jacking could the main physical process leading to failure by causing microcrack propagation. 相似文献
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The Sea to Sky Corridor has experienced hundreds of historic and prehistoric landslides. The most common types of historical
landslides are rock falls and debris flows, which are relatively small in volume but can be damaging. These types of failures
are more common in the southern part of the corridor, between Horseshoe Bay and Porteau, where infrastructure has been built
in close proximity to steep slopes. Farther north, fewer landslides have been reported historically, but those that have been
recorded are usually large and date to prehistoric time (e.g., Cheekye fan and Mystery Creek rock avalanche). As part of a
Geological Survey of Canada surficial geology and landslide inventory mapping study, Mystery Creek rock avalanche, near Whistler,
British Columbia, was sampled for 36Cl dating. Samples were collected from three large flat boulders of quartz diorite in the rock avalanche deposit to test a
correlation with the previously reported radiocarbon age of 800 ± 100 years BP on charcoal. One sample revealed a mean age
of 2,400 years and the other two, 4,300 and 4,800 years, respectively. These new results point to four possible interpretations:
(1) Mystery Creek landslide is about 800 years old; (2) Based on the overlapping 2σ uncertainties, the rock avalanche took
place between 2,200 and 3,600 years ago; (3) The rock avalanche deposit is 2,400 years old and the other two blocks are too
old; and (4) The rock avalanche is between 4,300 and 4,800 years old. Although there is strength in numbers and it is likely
that the age varies between 4,300 and 4,800 years, we favor the second interpretation where the age range is broader and statistically
significant for all three samples. Moreover, at this time, we favor discounting the radiocarbon age based on a greater number
of samples analyzed for 36Cl analysis and lack of detailed information on the charcoal sampling. The causes and triggers of the Mystery Creek rock avalanche
remain unknown, but direct glacial debuttressing can be ruled out. Some of the causes are likely a combination of the regional
tectonic setting which produced preferential planes of weakness reflected in the trend of major faults, headscarp, and reverse
scarps. Yearly cycles of freezing and thawing are considered a plausible cause based on present-day climate records. Finally,
a large earthquake still remains a possible trigger because of the active tectonic setting and the presence of potentially
contemporaneous landslides in the same area. Mystery Creek rock avalanche and other historic and pre-historic landslides contributed
to validation of a heuristic rock fall/rock slide/rock avalanche susceptibility mapping study, in which their headscarps correlated
well with medium-high to high susceptibility zones. In terms of hazard assessment, Mystery Creek rock avalanche, although
pre-historic in age, occurred in present-day climatic and geological conditions. This poses a threat to infrastructure such
as the Sea to Sky Highway, railway, and power line. 相似文献
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Results of intensive archaeological surveys conducted within two environmentally contrastive settings in the Nashville Basin of Tennessee demonstrate that prehistoric human activity was much more extensive in the inner Basin where the Duck River floodplain was flanked by patchy upland vegetation relative to the outer Basin where upland vegetation was more homogeneous. Vertebrate remains from caves and rockshelters show that the inner Basin supported such patchy upland vegetation throughout the known period of hunter-gatherer occupation of the area. There is close correspondance between periods when forest openings were most prevalent (i.e., Late Pleistocene/Early Holocene and Mid-Holocene) and times when prehistoric human occupation of the inner Basin was most intensive (Paleoindian and Middle Archaic). Comparisons of major artifact categories from systematic collections of various landform surfaces show that the T2 terrace was the most extensively utilized by prehistoric hunter-gatherers. the T3/valley slope, the uplands, and the T1 produced progressively lower artifact densities. Results of systematic backhoe trenching indicate that substantial Holocene aggradation accounts for the seemingly minor use of the T1. 相似文献
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通过对塔里木盆地柯平隆起西克尔地区中下奥陶统露头21号点塌体几何尺度的观测、岩性和岩相的观察描述、断裂(裂隙)系统的分析、塌体与围岩地层及围岩地层之间的关系分析,结果表明该塌体不具岩溶垮塌的特征,而具有山体滑坡的性质,具体表现为塌体水平向运动的剪切帚状节理及与围岩间的边界断裂、山体整体运动滑塌的地层完整性、山体崩塌-倒塌、滑塌的似角砾岩及不同围岩间的地层产状的变化。对山体成因的分析表明,山体在滑坡过程中经历了崩塌-倒塌、滑塌作用。其滑坡可能原因是塌体位于古岩溶洼地的一端,这为滑坡提供了地质条件;而加里东期走滑断裂的后期活动成为山体滑坡的触发因素。 相似文献
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岩石地层数字化与可视化是数字地层研究的基础, 是地层学从传统离散式描述中解脱出来探索简明的、科学的描述模式的开始.以基本岩石地层单元为“地层细胞”, 探索了一个简单的沉积单元是如何经历侵蚀、改造、埋藏、成岩, 最终形成多种复杂成层岩系的地质过程, 并以自主研发的一维岩石地层数字描述系统为平台实现了对亮甲山组岩石地层的一维数字描述.经调查证实, 虚拟运算的结论符合野外地质调查所观察到的现象.亮甲山组岩石地层的数字描述揭示, 尽管不同地区亮甲山组地层记录表象差异显著, 但它们都源自于相同的基本岩石地层单元, 为定义亮甲山组岩石地层单位提供了一种新的理论、程序与技术方法, 同时为定量描述古盆地系统的运动幅度、速率等细节提供了理论基础与技术方法, 既节省了野外及室内研究的重复工作量, 还可实现对岩石地层蕴藏信息的深度挖掘. 相似文献