共查询到20条相似文献，搜索用时 135 毫秒
1.
沉积型（贡溪式）重晶石矿床模式 总被引：5，自引：0，他引：5
车勤建 《大地构造与成矿学》1995,19(3):288-289
沉积型（贡溪式）重晶石矿床模式车勤建（湖南省地质研究所，长沙４１０００７）ＡＭＥＴＡＬＬＯＧＥＮＩＣＭＯＤＥＬＦＯＲＳＥＤＩＭＥＮＴＡＲＹＧＯＮＧＸＩ－ＴＹＰＥＢＡＲＩＴＥＤＥＰＯＳＩＴＳ￥ＣＨＥＱｉｎｊｉａｎ（ＨｕｎａｎＩｎｓｔｉｔｕｔｅｏｆＧｅｏ... 相似文献
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华南南盘江盆地早三叠世钙质微生物丘与生物层 总被引：1，自引：0，他引：1
在南盘江盆地海相弧立的碳酸盐台地内部发现早三叠世生物骨架灰岩。它们发育于２个层位：１．三叠系最底部哥里斯巴赫阶（Ｇｒｉｅｓｂａｃｈｉａｎ）,为１５ｍ厚的生物层;２．下三叠统上部史密斯阶－－斯帕斯阶（Ｓｍｉｔｈｉａｎ－－Ｓｐａｔｈｉａｎ）,为１．５ｍ厚弧立的穹隆形或倒置的贺锥形钙质微生物丘。这些钙质微生物丘与生物层是由坚硬的钙质策生物骨架组成,这些骨架围限出１￣３ｃｍ大小的内部孔洞网,期间充以团粒和 相似文献
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含油气沉积盆地深部地下水化学场分布特征研究 总被引：2，自引：0，他引：2
李广贺 《长春地质学院学报》1995,25(1):52-58
根据含油气沉积盆地深部地下水水化学特征，利用Ｐｉｔｚｅｒ模型，质量平衡模型及溶度积计算的数学模型，对我国东部沉积盆地深部地下水的化学场进行了定量研究。克服了传统水文地球化学模型在研究中－高盐度地下水中化学组分分布及其存在形式方面的限制，对盆地深部（１１００－２０００ｍ）中，高盐度地下水中的主要指示生物矿苏打（ＮａＨＣＯ３）和石膏（ＣａＳＯ４．２Ｈ２Ｏ）的饱和程度进行了定量评价，以此研究沉积盆地中与 相似文献
4.
《Scientia Geologica Sinica》1997,(3)
ＳＯＭＥＮＥＷＯＰＩＮＩＯＮＳＡＢＯＵＴＴＲＩＡＳＳＩＣＧＡＳＴＲＯＰＯＤＡＳＳＥＭＢＬＡＧＥＳＩＮＣＨＩＮＡＰａｎＹｕｎｔａｎｇ（ＧｒａｄｕａｔｅＳｃｈｏｌ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎｃｅｓ，Ｂｅｉｊｉｎｇ１０００３９）（Ｒｅｃｅ... 相似文献
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根据中生代火山岩和侵入岩的岩石类型与组合及其岩石化学特征等，将中国东南中生代大陆边缘分成陆缘火山（岩浆）弧（Ｃｖａ）、陆缘弧后（间）火山盆地带（Ａｂｖ）和裂陷火山（岩浆）带（Ｒｖ），并深入研究了它们的Ｓｒ、Ｏ、Ｐｂ和Ｓｍ、Ｎｄ同位素组成特征。Ｃｖａ具较低的ＩＳｒ和δ１８Ｏ值及变化较大的Ｐｂ同位素组成与较高的εＮｄ值；Ａｂｖ具较高的ＩＳｒ和δ１８Ｏ值及较稳定的Ｐｂ同位素组成与较低的εＮｄ值；Ｒｖ则具较低（较稳定）的ＩＳｒ值和Ｐｂ同位素组成及变化较大的δ１８Ｏ值与εＮｄ值。由此推断，Ｃｖａ和Ａｂｖ的岩浆均为陆缘亏损地幔与上地壳成分混合形成（前者地幔成分居多，后者以地壳成分为主），Ｒｖ的岩浆则具陆内交代－亏损地幔与较多的下地壳物质混合源的成因特征。 相似文献
7.
Recent Progress on Global Change Research in China 总被引：2，自引：0，他引：2
ＲＥＣＥＮＴＰＲＯＧＲＥＳＳＯＮＧＬＯＢＡＬＣＨＡＮＧＥＲＥＳＥＡＲＣＨＩＮＣＨＩＮＡＦｕＣｏｎｇｂｉｎ，ＹｅＤｕｚｈｅｎｇ（ＣｈｉｎａＣｏｍｍｉｔｔｅｅｆｏｒＩＧＢＰ，ＣＡＳＴ，Ｂｅｉｊｉｎｇ１００００８）ＲＥＣＥＮＴＰＲＯＧＲＥＳＳＯＮＧＬＯＢＡ... 相似文献
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１：５万区调中Ｒｎ－Ｈｇ联测及~（２１０）Ｐｏ等综合指标测量方法技术和应用研究ＴＥＣＨＮＩＱＵＥＳＡＮＤＡＰＰＬＩＣＡＴＩＯＮＯＦＣＯＭＢＩＮＥＤＲｎ－ＨｇＭＥＡＳＵＲＥＭＥＮＴＳＡＮＤＣＯＭＰＯＳＩＴＥＩＮＤＥＸＥＳ（~（２１０）ＰｏＡＮＤＯＴＨＥＲ... 相似文献
10.
《全球沉积岩数据库》讲座（三）叶健骝，南君亚，杨卫东（中国科学院地球化学研究所贵阳）第三讲全球沉积岩数据库管理系统──ＦＯＸＳＥＤＢＡ及其使用方法ＦＯＸＳＥＤＢＡ是由ＩＧＣＰ２６９项目中国工作组根据ＳＥＤＢＡ数据结构模型在ＰＣ系列微计算机上开发研制的... 相似文献
11.
Porphyry copper potential mapping using the weights of evidence model in a GIS,northern Shahr e Babak,Iran 总被引：1，自引：0，他引：1
A variety of spatial geological data were compiled, evaluated and integrated to produce a potential map for porphyry copper deposits in the northern Shahr e Babak, Iran, within a total area of approximately 408 km2. Remotely sensed data including LANDSAT Thematic Mapper were used to create the hydrothermal alteration haloes around intrusive bodies. Geological data, such as exposed granitic to intermediate intrusions, and part of the lineaments were extracted from available geological maps. Aeromagnetic data were also used to extract magnetic anomalies and extra lineaments. The Conditional Independence test was carried out on five binary maps representing diagnostic deposit recognition criteria, and four of them were then integrated using a weights of evidence model. The procedure generated a posterior probability map identifying favourable areas for porphyry copper deposits. The final map highlights the most important known copper deposits in high favourability domains. Some new target areas are also located in the favourability map and warrant further investigation. 相似文献
12.
D. N. Obiora J. C. Ibuot U. D. Alhassan F. N. Okeke 《International Journal of Environmental Science and Technology》2018,15(11):2423-2432
Vertical electrical soundings technique was used to evaluate the aquifer characteristics and distribution in the northern part of Paiko in Nigeria. A total of thirty vertical electrical soundings were carried out using ABEM SAS4000 Terrameter, and the data was analyzed both manually and with software (Resist software). The result revealed the aquifer resistivity and thickness to vary from 10.9 to 80,368 Ωm, and 1.06 to 72 m, respectively. Also, hydraulic conductivity ranges from 0.010267 to 41.61928 m/day while transmissivity values range from 0.035215 to 70.09302 m2. The hydrogeological maps (hydraulic conductivity and transmissivity image maps) showed the variations of these parameters in the study area and that the southwestern part of the area has prolific aquifer. 相似文献
13.
In the present study, an attempt has been made to evaluate the seismic hazard considering local site effects by carrying out detailed geotechnical and geophysical site characterization in Bangalore, India to develop microzonation maps. An area of 220 km2, encompassing Bangalore Mahanagara Palike (BMP) has been chosen as the study area. Seismic hazard analysis and microzonation of Bangalore are addressed in three parts: in the first part, estimation of seismic hazard is done using seismotectonic and geological information. Second part deals with site characterization using geotechnical and shallow geophysical techniques. In the last part, local site effects are assessed by carrying out one-dimensional (1-D) ground response analysis (using the program SHAKE2000) using both standard penetration test (SPT) data and shear wave velocity data from multichannel analysis of surface wave (MASW) survey. Further, field experiments using microtremor studies have also been carried out for evaluation of predominant frequency of the soil columns. The same has been assessed using 1-D ground response analysis and compared with microtremor results. Further, the Seed and Idriss simplified approach has been adopted to evaluate the soil liquefaction susceptibility and liquefaction resistance assessment. Microzonation maps have been prepared with a scale of 1:20,000. The detailed methodology, along with experimental details, collated data, results and maps are presented in this paper. 相似文献
14.
Flood monitoring, mapping and assessing capabilities using RADARSAT remote sensing, GIS and ground data for Bangladesh 总被引：3，自引：1，他引：2
Remote sensing is the most practical method available to managers of flood-prone areas for quantifying and mapping flood impacts. This study explored large inundation areas in the Maghna River Basin, around the northeastern Bangladesh, as determined from passive sensor LANDSAT data and the cloud-penetrating capabilities of the active sensors of the remote imaging microwave RADARSAT. This study also used passive sensor LANDSAT wet and dry images for the year 2000. Spatial resolution was 30 m by 30 m for comparisons of the inundation area with RADARSAT images. RADARSAT images with spatial resolution of 50 m by 50 m were used for frequency analysis of floods from 2000 to 2004. Time series images for 2004 were also used. RADARSAT remote sensing data, GIS data, and ground data were used for the purpose of flood monitoring, mapping and assessing. A supervised classification technique was used for this processing. They were processed for creating a maximum water extent map and for estimating inundation areas. The results of this study indicated that the maximum extent of the inundation area as estimated using RADARSAT satellite imaging was about 29, 900.72 km2 in 2004, which corresponded well with the heavy rainfall around northeast region, as seen at the Bhairab Bazar station and with the highest water level of the Ganges–Brahmaputra–Meghna (GBM) Rivers. A composite of 5 years of RADARSAT inundation maps from 2000 to 2004, GIS data, and damage data, was used to create unique flood hazard maps. Using the damage data for 2004 and the GIS data, a set of damage maps was also created. These maps are expected to be useful for future planning and flood disaster management. Thus, it has been demonstrated that RADARSAT imaging data acquired over the Bangladesh have the ability to precisely assess and clarify inundation areas allowing for successful flood monitoring, mapping and disaster management. 相似文献
15.
Hannah R. Griscom Scott N. Miller Thomas Gyedu-Ababio Ramesh Sivanpillai 《GeoJournal》2010,75(2):163-173
Considerable land cover changes have occurred in the Luvuvhu catchment in northeastern South Africa in the past two decades.
These changes are associated with human population growth and may be contributing to observed reductions in winter river baseflows
and increased episodes of river drying within Kruger National Park. Six-class land cover maps of the catchment were created
from 1978 (MSS) and 2005 (TM) Landsat imagery using an iterative technique. Results indicate a 1,000 km2 (12%) increase in Bare Ground between 1978 and 2005, with a concomitant decrease in shrubland and indigenous forest cover.
Overall classification accuracy in the 2005 image was 80%. Classification was most accurate for Water and Pine classes (100
and 92%) and least accurate for Indigenous Forest (46%), primarily due to misclassification as Shrubland. These maps are suitable
for land cover change and landscape modeling analyses, and can serve as baseline data for further research. 相似文献
16.
Hakan Mete Dogan 《Journal of Earth System Science》2009,118(6):701-710
Utilizing remote sensing (RS) and geographic information systems (GIS) tools, mineral composite characteristics (ferrous minerals
(FM), iron oxide (IO), and clay minerals (CM)) of the Kelkit River Basin (15913.07 km2) in Turkey were investigated and mapped. Mineral composite (MC) index maps were produced from three LANDSAT-ETM+ satellite
images taken in 2000. Resulting MC index maps were summarized in nine classes by using ‘natural breaks’ classification method
in GIS. Employing bi-variety correlation analysis, relationships among index maps were investigated. According to the results,
FM and IO index maps showed positive correlation, while CM index map is negatively correlated with FM and IO index maps. Negative
correlations between iron and clay variables suggested that the dominant clay minerals of the study area might be smectite,
illite, kaolinite, and chlorite, which have little or no iron content. Using field data for which their geographic coordinates
had been determined by global positioning system (GPS), developed MC maps were verified, and found dependable for environmental
and ecological modeling studies. 相似文献
17.
T. V. Swetha Girish Gopinath K. P. Thrivikramji N. P. Jesiya 《Environmental Earth Sciences》2017,76(12):428
The efficiency of GIS, RS and multi-criteria tools in isolating potential groundwater (GW) zones in the Kuttiyadi River basin (KRB), Kerala, has been robustly demonstrated by analysis of relevant data. To infer geohydrological makeup and consequent behavior of the KRB in respect of GW potential, firstly, various thematic layers viz. geomorphology, geology, slope, soil, lineament density and drainage density, were created. Secondly, thematic layers and their features were assigned suitable weights on the Saaty’s scale according to their relative significance for the presence and potential of GW. The assigned weights of the layers and their features were normalized using analytic network process method, and then the selected thematic maps were integrated in GIS using weighted overlay method to create the final groundwater prospect zone map. From the outcomes, the groundwater prospect zones of the KRB basin was found to be very good (166.21 km2), good (92.01 km2), moderate (180.33 km2), poor (237.25 km2), which constitute 24, 15, 26 and 35% of the study area, respectively. The GW prospect zone map was finally validated using geohydrology of area and GW level data from 43 phreatic wells in the study area. This study showed that groundwater prospect zone demarcation along with multi-criteria decision making is a powerful tool for proper utilization, planning and management of the precious groundwater resource. 相似文献
18.
Ezzadin N. Baban Aram N. Tawfiq Kakarash I. M. Gardi 《Arabian Journal of Geosciences》2014,7(9):3575-3588
The present study seeks to interpret seismic reflection data for an area measuring approximately about 1,450 km2 within the Erbil plain in the Kurdistan Region of Iraq to produce subsurface geological pictures. Thirteen seismic lines were identified by the Iraqi Oil Exploration Company using dynamite sources and then processed; then, a seismic line, BH-15, of around 432.5 km total length was used in this study. Three horizons (reflectors) were selected and identified by tying them directly to Demir Dagh well no. 1, these are H1, a reflector that represents the near top of the Lower Fars Formation; H2, a reflector that represents the top of the Pila Spi Formation; and H3, a reflector that represents the top of the Shiranish Formation. The qualities of the reflectors range between fair and good. All the isochrone and depth maps and 3D view pictures of the reflectors show the same main subsurface structural features trending in a NW–SE direction, namely, Erbil trough, Sherawa trough, and the southeastern plunge of the Demir Dagh anticline. Ninety-five normal and reverse-type faults trending in a NW–SE direction were detected. Also, the maps show that the reflectors tend to increase in dipping and deepening towards the southeastern and eastern parts. 相似文献
19.
Hassan Yeganeh Seyed jamale Khajedein Fazel Amiri Abdul Rashid B. Mohamed Shariff 《Arabian Journal of Geosciences》2014,7(1):287-298
The aim of the present research is to monitor changes in herbage production during the grazing season in the Semirom and Brojen regions, Iran, using multitemporal Moderate Resolution Imaging Spectroradiometer (MODIS) data. At first, various preprocessing steps were applied to a topography map. The atmospheric and topographic corrections were applied using subtraction of the dark object method and the Lambert method. Image processing, including false-color composite, principal component analysis, and vegetation indices were employed to produce land use and pasture production maps. Vegetation sampling was carried out over a period of 4 months during June–September 2008, using a stratified random sampling method. Twenty random sampling points were selected, and herbage production was estimated and verified with the double-checking method. Four MODIS data sets were used in this study. The models for image processing and integrating ground data with satellite images were processed, and the resulting images were categorized into seven classes. Finally, the land covers were verified for accuracy. A postclassification analysis was carried out to verify the seven class change detections. The results confirmed that Normalized Difference Vegetation Index (NDVI) and Soil-Adjusted Vegetation Index (SAVI) maps had a close relationship with the field data. The indices produced with shortwave infrared bands had a close relationship with field data where the ground cover and yields were high. The R 2 value observed was 0.85. The changes in the pasture vegetation were high during the growing season in more than 90 % of the pastures. During the growing season, most changes in the pastures belonged to class 5 and 2 in the NDVI and SAVI index maps, respectively. 相似文献
20.
Shabnam Hasani Omid Asghari Faramarz Doulati Ardejani Saeed Yousefi 《Environmental Earth Sciences》2017,76(15):532
Mining activities and resulting wastes can be considered as one of the most important sources of hazardous elements in the environment. Knowledge of the spatial distribution of toxic elements in waste dump systems is necessary to assess environmental hazard and strategy. To achieve this goal, this paper investigates spatial distribution of toxic elements using statistical and geostatistical analysis. A total of 58 soil samples were collected, and the amount of As, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb and Zn was then determined at “Sarcheshmeh” copper mine waste dumps. In order to evaluate the presence of multivariate outliers, Mahalanobis distance technique (D 2) was applied and the multivariate outlier samples were removed. This resulted in an increase in correlation coefficient. To reduce dimension of data set, principal component analysis was applied and four principal components were determined which indicate 83.463% of the total variance of data set. Estimated PCs together with the toxic elements maps based on the ordinary kriging display aggregation of toxic elements in some parts, and validity of predictions was evaluated using the leave-one-out cross-validation method. The regression coefficients of estimated and observed values presented the reliability of the kriging estimates. Sequential Gaussian simulation method was applied for principal components due to similar results of estimated principal components and toxic elements. The results of simulation maps are almost identical to estimated outcomes. 相似文献