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1.
An understanding of what influences sinkhole formation and the ability to accurately predict sinkhole hazards is critical
to environmental management efforts in the karst lands of southeastern Minnesota. Based on the distribution of distances to
the nearest sinkhole, sinkhole density, bedrock geology and depth to bedrock in southeastern Minnesota and northwestern Iowa,
a decision tree model has been developed to construct maps of sinkhole probability in Minnesota. The decision tree model was
converted as cartographic models and implemented in ArcGIS to create a preliminary sinkhole probability map in Goodhue, Wabasha,
Olmsted, Fillmore, and Mower Counties. This model quantifies bedrock geology, depth to bedrock, sinkhole density, and neighborhood
effects in southeastern Minnesota but excludes potential controlling factors such as structural control, topographic settings,
human activities and land-use. The sinkhole probability map needs to be verified and updated as more sinkholes are mapped
and more information about sinkhole formation is obtained. 相似文献
2.
广西都安喀斯特石漠化的分布特征及其与岩性的空间相关性 总被引：22，自引：2，他引：20
在以广西都安瑶族自治县为研究对象 ,以RS与GIS一体化为分析手段 ,首先采用TM影像为背景资料 ,辅以地形图、土地利用图、土壤图、地质图以及GPS实测数据库等相关资料综合分析的基础上 ,建立石漠化分级的遥感影像解译指标体系 ,生成都安县石漠化分级分布图和数字化岩性图 ,然后从空间相关性的角度阐明了不同级别石漠化与碳酸盐岩岩性之间的内存联系 相似文献
3.
Du'an Yao Autonomous County is a typical area for the distribution of karst rocky desertification in Guangxi.The indices for the grades of rocky desertification are selected according to the scientific meaning of karst rocky desertification and after the interpretative symbol system of rocky desertification. RS images are established by the landscape characteristics of Du'an karst and its TM image. Relying on RS & GIS means and taking land use map as base map, this paper conducts synthetic analysis on the 1999a TM image (126-043) and the correlation data involving landform, soil, geological map and GPS-database and photo on the spot, and brings forth a map showing the Du'an rocky desertification grades and a digital lithology map. As can be viewed from spatial correlation, the inherent connection is also illuminated between the various levels of rocky desertification and the carbonate lithology. 相似文献
4.
随着人口的增长、经济的发展,一些新高速公路的建设不可避免地经过岩溶发育地区,水任- 南宁高速公路No. 4合同段大约有10km穿过岩溶极为发育的岩溶谷地,下伏著名的地苏地下河系,对路基的稳定性造成巨大威胁。本文以该路段为例,从多源空间数据的管理、数据可视化、动态分段、数据查询、空间分析和专题地图制作等方面介绍GIS在高速公路岩溶路基病害研究中的应用。 相似文献
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6.
荔波地层岩性以碳酸盐岩为主,且降雨量丰富,具有形成地质旅游资源优越的地理、地质及外部条件。荔波喀斯特地貌极其发育,地质景观旅游资源单体特别丰富。通过贵州省荔波县旅游资源大普查,对荔波县下属8乡镇旅游资源单体进行了全方面、全领域调查和研究,共新发现单体1 106个,其中入级单体856个,涵盖除康体养生旅游类的11个主类。优良级(三级及以上)资源单体共132个,占入级单体总量的15. 42%,主要为地文景观、建筑设施、水域风光、乡村旅游及生物景观等大类。其中地文景观及水域风光入级资源单体共计381个,占入级单体总量的44. 51%;优良级资源单体79个,占优良级单体总量的59. 85%。本文以大普查成果为基础,重点对荔波县地质景观资源单体进行综合分析和评价,为后期旅游资源开发提供实事材料和理论基础。 相似文献
7.
LARS RONNERT MATS R. NYBORG 《Boreas: An International Journal of Quaternary Research》1994,23(4):311-319
Four geologic units previously mapped in southern Jameson Land. E ast Greenland (Funder 1978, 1990) are identifiable on a false colour composite of Landsat Thematic Mapper (TM) spectral hands TM5. TM4 and TM1. The area covered by the Weichselian glaciations has a fresh glacial morphology and a less developed drainage system than the older landscape. The Weichselian glaciers reached more than 200 m a.s.l. in the west. but only about 100 m a.s.l. in the east. A contextual analysis (local frequency and local orientation) was included in a Maximum Likelihood classification (M-L) to map the extent of the Weichselian glaciations. Deposits correlated with the Saalian Scoreshy Sund glaciation are found on the central plateaux of Jameson Land. Landsat TM geological mapping of the surficial distribution of deposits from the Scoreshy Sund glaciation and of weathered Jurassic sandstone or deposits with a high percentage of such sandstone was done using a supervised Maximum Likelihood procedure. Except for the mapping of thc extent of the Late Weichselian Flakkerhuk glaciation, the Maximum Likelihood boundaries between units are in general agrecnient with earlier mapping or with the visual interpretation of the false colour composite. A strong vegetational influence. and similar spectral reflectance lrom deposits of different age due to similarities in lithological composition reduced the possibility of an independent remote sensing approach. Taking already existing general geological knowledge and chronology into account allowed successful Landsat TM geological mapping. 相似文献
8.
蜀南地区茅口组为一套沉积稳定的巨厚层生物碎屑灰岩,基质致密性脆。中二叠世末的东吴运动使蜀南地区茅口组顶部发育古风化壳岩溶,古岩溶地区水系控制着古岩溶的发育和演化。在研究古地貌恢复方法的基础上,分析研究区地层特征和区域构造背景,采用印模法进行古地貌恢复,进而研究了古岩溶地区的水系发育特征。在此基础上,结合风化壳表面侵蚀溶蚀特征、沉积物性质、地貌组合形态、钻井和地震资料,把研究区划分为岩溶台地、岩溶陡坡、岩溶缓坡及岩溶盆地4种二级地貌单元和溶丘洼地、岩溶槽谷、峰林平原等10种三级地貌单元,进一步分析了各种地貌单元的岩溶特征,为下一步的储集层预测提供了有利的目标。 相似文献
9.
J. M. Rine R. C. Berg J. M. Shafer E. R. Covington J. K. Reed C. B. Bennett J. E. Trudnak 《Environmental Geology》1998,35(4):263-277
A methodology was developed to evaluate and map the contamination potential or aquifer sensitivity of the upper groundwater
flow system of a portion of the General Separations Area (GSA) at the Department of Energy's Savannah River Site (SRS) in
South Carolina. A Geographic Information System (GIS) was used to integrate diverse subsurface geologic data, soils data,
and hydrology utilizing a stack-unit mapping approach to construct mapping layers. This is the first time that such an approach
has been used to delineate the hydrogeology of a coastal plain environment. Unit surface elevation maps were constructed for
the tops of six Tertiary units derived from over 200 boring logs. Thickness or isopach maps were created for five hydrogeologic
units by differencing top and basal surface elevations. The geologic stack-unit map was created by stacking the five isopach
maps and adding codes for each stack-unit polygon. Stacked-units were rated according to their hydrogeologic properties and
ranked using a logarithmic approach (utility theory) to establish a contamination potential index. Colors were assigned to
help display relative importance of stacked-units in preventing or promoting transport of contaminants. The sensitivity assessment
included the effects of surface soils on contaminants which are particularly important for evaluating potential effects from
surface spills. Hydrogeologic/hydrologic factors did not exhibit sufficient spatial variation to warrant incorporation into
contamination potential assessment. Development of this contamination potential mapping system provides a useful tool for
site planners, environmental scientists, and regulatory agencies.
Received: 1 April 1997 · Accepted: 4 November 1997 相似文献
10.
James M. Rine John M. Shafer Elzbieta Covington Richard C. Berg 《Hydrogeology Journal》2006,14(8):1620-1634
Published information on the correlation and field-testing of the technique of stack-unit/aquifer sensitivity mapping with documented subsurface contaminant plumes is rare. The inherent characteristic of stack-unit mapping, which makes it a superior technique to other analyses that amalgamate data, is the ability to deconstruct the sensitivity analysis on a unit-by-unit basis. An aquifer sensitivity map, delineating the relative sensitivity of the Crouch Branch aquifer of the Administrative/Manufacturing Area (A/M) at the Savannah River Site (SRS) in South Carolina, USA, incorporates six hydrostratigraphic units, surface soil units, and relevant hydrologic data. When this sensitivity map is compared with the distribution of the contaminant tetrachloroethylene (PCE), PCE is present within the Crouch Branch aquifer within an area classified as highly sensitive, even though the PCE was primarily released on the ground surface within areas classified with low aquifer sensitivity. This phenomenon is explained through analysis of the aquifer sensitivity map, the groundwater potentiometric surface maps, and the plume distributions within the area on a unit-by- unit basis. The results of this correlation show how the paths of the PCE plume are influenced by both the geology and the groundwater flow. 相似文献
11.
《Chemie der Erde / Geochemistry》2016,76(2):197-210
Geochemical maps can provide us with much information on geology, earth surface processes and anthropogenic pressure and are valuable tools for ore prospecting and land management. Stream sediments represent an integral of the various possible sources of sediments upstream from the sampling point therefore there can be multiple signal sources but generally the prevailing signal source is the one related to bedrock geology. Stream sediments collected from active second-order channels including singular geological units, were selected in order to determine the geochemical characteristics of each unit. The aim of this study was to analyse their potential for using them to integrate geological interpretation and produce a geologically-oriented geochemical map. From the 770 samples collected for a regional geochemical mapping program, we selected 149 samples whose catchment basin included only one of the members recognized within the Marnoso–Arenacea formation. This Middle-Upper Miocene (Langhian–Tortonian) turbiditic unit forms the backbone of the Romagna Apennines and has been subdivided into 14 members according to age and lithostratigraphic criteria. The results indicate that there are marked differences in the composition of the members of the Marnoso Arenecea formation which indicate the provenance of the sediment and the palaeogeographic evolution of the units. By means of univariate and multivariate statistical analyses (Factor analyses) two main types of sediment compositions are identified: Tortonian members are characterized by sialic coarse grain- sediments while the Langhian–Serravallian members are richer in carbonate fraction, slightly enriched in a mafic contribution. This study elaborated the geochemical data from a geological point of view by integrating the information available in literature to spatially extend the interpretation based on limited site observation as for petrographic studies. In general, the geochemical map based on a geological unit could be a useful tool for carrying out the geological reconstruction of a complex area. 相似文献
12.
《Chemie der Erde / Geochemistry》2016,76(1):49-62
Geochemical maps can provide us with much information on geology, earth surface processes and anthropogenic pressure and are valuable tools for ore prospecting and land management. Stream sediments represent an integral of the various possible sources of sediments upstream from the sampling point therefore there can be multiple signal sources but generally the prevailing signal source is the one related to bedrock geology. Stream sediments collected from active second-order channels including singular geological units, were selected in order to determine the geochemical characteristics of each unit. The aim of this study was to analyze their potential for using them to integrate geological interpretation and produce a geologically-oriented geochemical map. From the 770 samples collected for a regional geochemical mapping program, we selected 149 samples whose catchment basin included only one of the members recognized within the Marnoso-arenacea formation. This middle–upper Miocene (Langhian–Tortonian) turbiditic unit forms the backbone of the Romagna Apennines and has been subdivided into 14 members according to age and lithostratigraphic criteria. The results indicate that there are marked differences in the composition of the members of the Marnoso arenecea formation which indicate the provenance of the sediment and the palaeogeographic evolution of the units. By means of univariate and multivariate statistical analyses (Factor analyzes) two main types of sediment compositions are identified: Tortonian members are characterized by sialic coarse grain-sediments while the Langhian–Serravallian members are richer in carbonate fraction, slightly enriched in a mafic contribution. This study elaborated the geochemical data from a geological point of view by integrating the information available in literature to spatially extend the interpretation based on limited site observation as for petrographic studies. In general, the geochemical map based on a geological unit could be a useful tool for carrying out the geological reconstruction of a complex area. 相似文献
13.
《Environmental Earth Sciences》2012,65(3):805-812
Karst topography is a landscape shaped by the dissolution of a layer or layers of soluble bedrock, usually limestone and evaporites.
Karstification in the Sivas basin (Turkey) has sculpted a beautiful landscape with a distinctive beauty and appeal for both
local inhabitants and visitors. Dolines are very special geological landscape features found in karst regions, and the Sivas
basin has several giant dolines amongst its thousands of smaller dolines. The basin constitutes a distinctive karst architecture
with a system of collapse and/or dolines and caves. Anyone who walks along the shores of a lake resulting from the collapse,
in this gypsum terrain, will be amazed with the lake and rocks that surround them. In this paper, dolines in the gypsum terrain
are evaluated and discussed according to their value as a “Geological Heritage”. Three main characteristics of dolines, namely
their scientific, aesthetic and ecosystem importance are considered and discussed. Dolines and karstified areas as representative
examples of landform types possess the three attributes for them to be considered as a Geological Heritage in that they demonstrate
the effect of erosion on the landform, geomorphic processes that are still active and a range of features characteristic of
the rock unit involved. 相似文献
14.
A 480-square-mile region within Will County, in northeastern Illinois, was used as a test region for the development of a methodology to map the sensitivity of aquifers to contamination. An aquifer sensitivity model was developed using a geographic information system (GIS) to overlay and combine several data layers. The components used for our model are: (1) depth to sand and gravel or bedrock, (2) thickness of the uppermost sand and gravel aquifer, (3) glacial drift thickness, and (4) bedrock geology. The model is an improvement over many previous aquifer sensitivity models because it combines specific information on depth to the uppermost aquifer with information on the thickness of the uppermost sand and gravel aquifer. This county-wide model results in an aquifer sensitivity map that can be a useful tool for making land-use planning decisions regarding aquifer protection and management of groundwater resources. 相似文献
15.
在甘肃和青海交界地区的1：257Y民和县幅、临夏市幅和定西市幅数字区域地质调查中,以“数字填图系统（RGMAP）”为平台,使用遥感ETM^＋数据和地形数据对岩石地层进行了信息挖掘。数据准备主要是遥感和数字地形多源信息的提取和预处理．从数字地形图的等高线数据中提取高程,进而提取汇水网络等水文信息和地形参数。遥感数据经过地形校正、线性增强、色彩拉伸,进行空间分辨率增强,经彩色合成并结合数字高程,实现了对调查区构造-地层区划和部分岩石地层单元的识别。实践证明该项工作是地质填图的重要辅助手段。 相似文献
16.
A new hydro-tectonic model, includes eight layers that affect karst hydrogeology was proposed for mapping of groundwater potential in karst areas of Gurpi Anticline, southwest Iran. To produce the groundwater potential map, remote sensing (RS) and GIS techniques were combined with fuzzy logic modeling. Criterion maps include the distances from discharge sites (D), the elevation difference from discharge sites (E), the distance from fractures (F), the fracture length density (L), the slope (O), the lithology (G), the distance from fractures intersections (I), and the fractures intersection density (C) were produced using GIS and RS techniques (DEFLOGIC layers). The approach of fuzzy sets was used to commensurate criterion maps, then fuzzy algebraic sum and gamma operators were applied to aggregate them. The weights of parameters of DEFLOGIC proposed in the range of 1 to 5, which standardized between 0 to 1, based on their importance in karst hydrogeology, professional judgments, and available exploration data. The final groundwater potential maps were verified by geoelectric and well-drilling data. The potential map prepared using fuzzy gamma operator with γ?=?0.92, which it is a flexible distinctive parameters of sum and product of fuzzy operator, depicts the best coincidence with exploration data. The final DEFLOGIC map shows the high groundwater potential in karst formations between Hati and Pebde valleys. The results support the efficiency of DEFLOGIC model to evaluating of groundwater potential in karst terrains, especially in Zagros ranges. 相似文献
17.
The curve number (CN) is a hydrologic parameter used to describe the stormwater runoff potential for drainage areas, and it is a function of land use, soil type, and soil moisture. This study was conducted to estimate the potential runoff coefficient (PRC) using geographic information system (GIS) based on the area’s hydrologic soil group, land use, and slope and to determine the runoff volume. The soil map for the study area was developed using GPS data carried on to identify the soil texture to be used in building a soil hydrological groups map. Unsupervised and supervised classifications were done to Landsat 5/7 TM/ETM image to generate land-use and land-cover map. This map was reclassified into four main classes (forest, grass and shrub, cropland, and bare soil). Slope map for Al-Baha was generated from a 30-m digital elevation model. The GIS technique was used to combine the previous three maps into one map to generate PRC map. Annual runoff depth is derived based on the annual rainfall surplus and runoff coefficient per pixel using raster calculator tool in ArcGIS. An indication that in the absence of reliable ground measurements of rainfall product, it can satisfactorily be applied to estimate the spatial rainfall distribution based on values of R and R 2 (0.9998) obtained. Annual runoff generation from the study area ranged from 0 to 82 % of the total rainfall. Rainfall distribution in the study area shows the wise use of identifying suitable sites for rainwater harvesting, where most of the constructed dams are located in the higher rainfall areas. 相似文献
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传统地质填图方法一般按成因划分第四系填图单位,但在半覆盖区,往往存在第四系不同成因物质混杂堆积的现象,若按成因划分填图单位,则会造成混乱。笔者在填图实践中,尝试按岩性划分第四系填图单位,这一做法能避免这种混乱,且有利于第四系中基岩信息的发掘,并能为勘查地球化学工作提供景观依据,这种新式填图方法可称为"第四系岩性填图法"。用岩性划分第四系填图单位需要使用统一的分类命名方案,本文使用了按碎屑特征进行分类的方案,主要考虑第四系松散堆积中碎屑的粒径、形态和含量变化。第四系岩性填图法中填图单位的划分需要参照这一分类命名方案,并可选用颜色、构造、次要碎屑类型等修饰性要素做为辅助划分依据。填图单位划分一般在踏勘和剖面实测中完成,第四系岩性填图法剖面测制较为复杂,除采用传统垂向测制方法外,还需运用横向测法和横向-垂向联合测法,通过剖面工作,可细化填图单位划分方案,并可评价不同填图单元基岩恢复的可靠性。第四系岩性填图法除需要编制传统地质图外,还需要编制基岩推断地质图或是在报告中制作插图以阐述此成果。 相似文献
20.
The Karst Feature Database (KFD) of Minnesota is a relational GIS-based Database Management System (DBMS). Previous karst feature datasets used inconsistent attributes to describe karst features in different areas of Minnesota. Existing metadata were modified and standardized to represent a comprehensive metadata for all the karst features in Minnesota. Microsoft Access 2000 and ArcView 3.2 were used to develop this working database. Existing county and sub-county karst feature datasets have been assembled into the KFD, which is capable of visualizing and analyzing the entire data set. By November 17 2002, 11,682 karst features were stored in the KFD of Minnesota. Data tables are stored in a Microsoft Access 2000 DBMS and linked to corresponding ArcView applications. The current KFD of Minnesota has been moved from a Windows NT server to a Windows 2000 Citrix server accessible to researchers and planners through networked interfaces. 相似文献