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1.
Sulfur is one of the havardous elements in coal The concentrations of sulfur are relatively high in coal.The major forms of sulfur in coal are pyritic,organic and sulfate.Pyritic and organic sulfur generally account for the bulk of sulfur in coal.Elemental sulfur also occurs in coal,but only in trace to minor amounts.When coals are burned,leached and washed,sulfur will be released in the form of sulfide and H2S,which then reach with O2,water and other substances to change into vitriol,and in some places it may form acid rain.And they will impact water environment,acidify the soil and do great harm to plants and human health.In this paper,on the basis of the data from the Yanzhou mining district,the distribution and concentrations of sulfur are analyzed and the existing forms of sulfur are studied.The variation of sulfur and its impact on the environments also are described when coal is used.  相似文献   

2.
Systematic analysis and comparative study of the chemical compositons of rocks and ores from the main types of zeolite deposits in the surroundings of the Songliao Basic have shown that the process of formation of zeolite from volcanic and pyroclastic rocks is generally characterized by the relative purification of SiO2,i.e.,SiO2/Al2O3 ratios tend to increase,alkali eart elements (CaO MgO)and H2O are relatively enriched,and the alkali metals(K2O Na2O)are depleted in their total amount.The alkali metals K and Na follow different rules of migration and enrichment during the formation of mordenite and clinoptilolite.In the process of formation of mordenite more Na^ will be imported and K^ will be lost remarkably.On the contrary,in the process of formation clinoptilolite more K^ will be incorporated and Na^ will become obviously depleted.  相似文献   

3.
The paper deals with the relatively weak permeable layer in a layered structure of a slope rock mass and itseffect on groundwater behaviour in the rock mass. When the whole groundwater table is declined in such typeof slope rock mass, the permeability of the relatively weak permeable layer in the middle will be several timeslower than that of the upper and lower permeable layers and consequently the water level in layers of differentpermeability will fall in different rates which will lead to a discontinuous phenomenon of the water body. Amethod of finite element simulation on a vertical two-dimensional profile is suggested for the study of the phe-nomenon and its application to practical situation is described. The calculation result shows that the existingweak permeable layer in a layered slope rock mass exerts unnegligible influence on the variation of water levelin the rock mass of a slope. The result also proves the applicability of the finite element simulation method.  相似文献   

4.
The process of salinization has increased dramatically over the past several decades in the northwest arid zone of China. Soil salinization has been recognized as a major environmental problem for many years in the Tarim River Basin. It is the key issue of solving the soil salinization problem to study interaction between water and salt in arid zone, which will provide useful principle and methodology to its solution. Taking Tarim River and Bosten Lake for example, by systematically collecting the basic data of hydrogeology, meteorology, and social economy, we analyzed the interaction of water and salt of Tarim River and Bostan Lake in natural and artificial conditions in aspects of basins, oases, lakes and marshes. The results showed that: (1) Temperature and precipitation are both increasing gradually in the whole Tarim River Basin, the climate tends to be come warmer and wetter, but the water quality condition is not optimistic; (2) At the end of the 1950s, mineralization degree was less than 1.0 g/L from the upper reaches to the lower reaches of the Tarim River. At present, it is more than 3.0 g/L in Alaer Lake (the upper reaches of the Tarim River) except in July, August and October, during which it is less than 1.0 g/L. In Qiala (the lower reaches), it is more than 1.0 g/L except in March, moreover, it is about 5.0 g/L in July and December. The eco-water conveyance project implementation has still not improved Tarim River's water quality condition; (3) Bostan Lake was a tiny salt-water lake in the late 1950s, but the water-soil development of the oasis has aggravated the salinization in recent thirty years. Since the West Pumping Station was brought into operation in 1982, the Bostan Lake which accumulated salt has begun to be desalted. We consider that climate may not be the key factor for salinization in this area. Instead, socio-economic factors relevant to human activities should be mainly responsible for such changes, as is confirmed by our further analysis. In order to improve present situation of water-soil salinization, water resources utilization and management should be strengthened, highly efficient and water-saving irrigating technology should be spread,  相似文献   

5.
Geoscience and high-level nuclear waste disposal: the Nordic scene   总被引:1,自引:0,他引:1  
In Norden, two countries, Sweden and Finland, are actively engaged in site investigations for the location of deep repositories for spent nuclear fuel from powerproducing nuclear reactors. These investigations are being carried out in crystalline rocks of the Fennoscandian Shield. In Sweden, a long history of site selection has led to the identification and investigation of two sites, Forsmark and Laxemar/Simpevarp, based on a strategy of combining favourable bedrock with consent by the local population. Surface-based geoscientific investigations of the two candidates, with extensive deep drilling, are now drawing to a close. A proposal as to which of the sites would be most suitable for the development of a deep repository will be submitted to the governmental regulatory authorities in 2009. In Finland, the site selection process was shorter and less politically controversial, and led to a "Decision in Principle" by the Finnish parliament, in May 2001, to develop a deep repository at the Olkiluoto site. The access tunnel to an underground rock characterisation facility at 400-500 m depth is at present under construction, accompanied by extensive geoscientific investigations in the subsurface. An application for a construction licence for a deep repository will be submitted in 2012. Although all sites are located in Precambrian crystalline rocks, the Swedish homogeneous granitic rocks, sites both lie in relatively whilst the Finnish site is located in an heterogeneous migmatite complex. The Nordic approach to high-level nuclear waste disposal in crystalline rock will be the theme of a Topical Symposium at the 33rd International Geological Congress at Oslo, in August 2008, and the three sites mentioned above will be the focus of Congress Excursion no. 14.  相似文献   

6.
7.
Scientific research and productive practice for earth history are inseparable from the accurate stratigraphic framework and time framework. Establishing the globally unified, precise and reliable chronostratigraphic series and geological time series is the major goal of the International Commission on Stratigraphy(ICS). Under the leadership of the ICS, the countries around the world have carried out research on the Global Standard Stratotype-section and Points(GSSPs) for the boundaries of chronostratigraphic systems. In the current International Chronostratigraphic Chart(ICC), 65 GSSPs have been erected in the Phanerozoic Eonothem, and one has yet been erected in the Precambrian Eonothem. Based on the progress of research on stratigraphy especially that from its subcommissions, the ICS is constantly revising the ICC, and will publish a new International Stratigraphic Guide in 2020. After continual efforts and broad international cooperation of Chinese stratigraphers, 10 GSSPs within the Phanerozoic Eonothem have been approved and ratified to erect in China by the ICS and IUGS. To establish the standards for stratigraphic division and correlation of China, with the support from the Ministry of Science and Technology, the National Natural Science Foundation of China and the China Geological Survey, Chinese stratigraphers have carried out research on the establishment of Stages in China. A total of 102 stages have been defined in the "Regional Chronostratigraphic Chart of China(geologic time)", in which 59 stages were studied in depth. In 2014, the "Stratigraphic Chart of China" was compiled, with the essential contents as follows: the correlation between international chronostratigraphy and regional chronostratigraphy of China(geologic time), the distributive status of lithostratigraphy, the characteristics of geological ages, the biostratigraphic sequence, the magnetostratigraphy, the geological events and eustatic sea-level change during every geological stage. The "Stratigraphical Guide of China and its Explanation(2014)" was also published. Chinese stratigraphers have paid much attention to stratigraphic research in south China, northeast China, north China and northwest China and they have made great achievements in special research on stratigraphy, based on the 1:1000000, 1:250000, 1:200000 and 1:50000 regional geological survey projects. Manifold new stratigraphic units were discovered and established by the regional geological surveys, which are helpful to improve the regional chronostratigraphic series of China. On the strength of the investigation in coastal and offshore areas, the status of marine strata in China has been expounded. According to the developing situation of international stratigraphy and the characteristics of Chinese stratigraphic work, the contrast relation between regional stratigraphic units of China and GSSPs will be established in the future, which will improve the application value of GSSPs and the standard of regional stratigraphic division and correlation. In addition, the study of stratigraphy of the Precambrian, terrestrial basins and orogenic belts will be strengthened, the Stratigraphic Chart of China will be improved, the typical stratigraphic sections in China will be protected and the applied study of stratigraphy in the fields of oil and gas, solid minerals, etc. will be promoted. On the ground of these actions, stratigraphic research will continue to play a great role in the social and economic development of China.  相似文献   

8.
The Altai-Junggar-Tianshan collage in southern Altaids is an important metallogenic domain in Central Asia that contain world-class copper-iron-nickel deposits. As an accretionary-type metallogenic system, the metallogenic processes of the Altai-Junggar-Tianshan collage is essential in understanding the genetic mechanism of ore deposits in general. Here in this paper we present a brief introduction to the project on the western part of the Southern Altaids, entitled “The deep structure and metallegenic processes of the North China accretionary metallogenic systems”.This project mainly focuses on the deep structure and metallogenic background of the Altai-Junggar-Tianshan collage by integrated studies from field geology, structural mapping, geochemistry and geophysical exploration. Multiple new geological and geophysical methods will be applied to make transparency of the Kalatongke and Kalatage ore clusters. This will update our understanding of the geodynamic processes of metallogenesis and lead to the development and foundation of new metallogenic theories in accretionary orogens.  相似文献   

9.
Acidic groundwater and surface water are common problems in coastal Australia causing massive fish kills, attack of concrete and steel structures, and clogging of waterways. The best solution is the construction of a permeable reactive barrier (PRB) to neutralise the acidic groundwater before entering nearby waterways. A PRB consists of a trench filled with reactive material that intersects the flow-path of a contaminant plume and ameliorates the contaminated groundwater. A PRB is being designed in a pilot scale study in ASS in southeastern Australia. The groundwater is acidic (pH 3) with high A1 (40 mg/L) and Fe (530 mg/L) levels. When the acidic groundwater comes into contact with this PRB, the acid will be neutralized by the alkaline reactive materials and the aluminum and iron will be removed from the groundwater. Twenty-five alkaline materials were tested for use in the PRB, with an emphasis on waste materials, including oyster shells and recycled concrete. Batch tests were used to select the best two reactive materials for use in the column tests. The pH achieved by each material was controlled by the reaction kinetics of the dominant alkaline component.  相似文献   

10.
Studying the influence of shale gas exploration and development on groundwater environment is the basis of guiding water environment protection in the process of shale gas exploration and development.Groundwater environmental pollution is concealed,complex and persistent.Once it is difficult to control the pollution,the current commercial shale gas development zones in Sichuan Basin that are mostly located in karst areas and highly sensitive to groundwater will be vulnerable to the impact of shale gas exploration and development.Based on the hydrogeological conditions of shale gas exploration and development area and combined with engineering analysis of exploration and development,various risk pathways that may affect the groundwater environment during process of shale gas exploration,mining well construction,mining operations and other stages were identified in this paper.Some existing risk pathways were proved by verification of typical areas and should not be ignored.Based on the actual situation of typical areas,the countermeasures of groundwater environmental protection in the process of shale gas exploration and development in karst areas were discussed.It is believed that the groundwater environment can be better protected by strengthening administration,research and application of new technologies,precise design,hydrogeological conditions,and research and feedback of groundwater environmental protection.  相似文献   

11.
The dissipative structure is an ordered structure.When a ssyterm is far from reaching equilibrium in the condition of non-equilibrium and exchanges some energy and material with the surroundings,this structure will be formed and preserved.Starting with the analysis of practical data,we attempt to use this theory to discuss the tectono-geochemical problems of some rock and ore-forming systems in faults.1.Ordered structure:Under the geological condition,due to the opening of a system in which energy and material are involved in geochemical action,the entropy tends to reduce gradually and substances evolve from non-ordered to ordered in structure.In the processes of formation of rocks and ores in faults,various layer-bands will be formed in rocks.2.Functional action:The physico-chemical activities which include pressure-creeping and thermal-diffusion as well as liquid diffusion have been shown.3.Fluctuating cycle:In the process of metamorphism,various changes in pressure,temperature and liquid are of fluctuation and periodicity.These may play an important role in the formation of rocks and minerals and the occurrence of ordered structures in fault zones.A few examples of mineral deposits in the middle and lower Yangtze River Valley are presented here,and the dissipative activities of rock-forming minerals and mineral-forming elements have been preliminarily established.  相似文献   

12.
In the future time the exploration of marine oil and gas will be one of the significant domains in China. In this paper the biomarker assemblage characteristics of oilshow in the Nanlinghu Formation of the Majiashan profile, which is located in Chaoxian County, south of Anhui Province, are described in the light of gas chromatography/mass spectrometric (GCMS) analysis on the qualitative and quantitative basis. Based on the investigation of the biomarker assemblage characteristics of possible source rocks developed in the area studied, a conclusion is drawn that the oilshow was generated from the Nanlinghu Formation source rocks (abbreviated as Tin), instead of the Qixia Formation source rocks (abbreviated as P1q). It is pointed out that the Tin is of strong potential for future oil exploration, and therefore much attention should be paid to it.  相似文献   

13.
Haphazard packing of equal and unequal spheres can be performed for the spheres of molecular sieve material with a density of 1.80.The packing of such spheres in air is equivalent to that of nat-ural grains in water.Packing concentrations of equal spheres have been obtained for different pac-king intensities.Unequal spheres can be regarded as equal ones in a wide range of diameter ratios,so far as the packing concentration is concerned.A threshold of diameter ratio exists at 0.70,be-low which the packing concentration is expected to increase.The variation curves of concentration vs.diameter ratio were established in the experiment.The result will help us to understand the process of sedimentation and the concentration of voids in sedimentary rocks.  相似文献   

14.
Three sporopollen assemblages are recognized for the first time from the Cretaceous Yimin Formation in the Hailar Basin of eastern Inner Mongolia. They are (in ascending order): the lmpardecispora-Aequitriradites- Clawttipollenites assemblage; the Triporoletes-Pilosisporites-Asteropollis assemblage; and the Appendicisporites- Asteropollis-Tricolpites assemblage, distributed in Members 1, 2 and 3 of the Yimin Formation respectively. Recognition of this biostratigraphic sequence is very important for the division and correlation of the Yimin Formation in the basin. Meanwhile, the age of the Yimin Formation is considered to be Barremian to Early Albian based on the palynological data.  相似文献   

15.
1 Background of the project and research route 1.1 Background of the project The Niuchangpin ski field at Shennongjia is designed as the biggest natural ski field in the Huazhong (central China) area, which will be a multifunctional ski field base incl…  相似文献   

16.
The Damintun depression is one of the four depressions in the Liaohe basin in northern China, and is a rift basin developed in the Paleogene. This paper discusses in detail the characteristics of pressure and fluid potential of the Damintun depression based on a synthesis of the data from boreholes, well tests and seismic surveys. Data from sonic logs, well tests and seismic velocity measurements are used to study the pressure characteristics of the areas. From the sonic log data, shales can be characterized as normally pressured, slightly overpressured or highly overpressured; from the well test data, the pressure-depth gradient in oil-producing intervals implies hydrostatic pressure in general. Most seismic profiles in the Damintun depression are of sufficiently high quality for seismic velocities to be measured. The fluid pressures, excess pressures and pressure coefficients in 47 representative seismic profiles are predicted using formula calculation methods, and further transformed to fluid potenti  相似文献   

17.
张忠  张宝贵等 《中国地球化学学报》2000,19(1):45-51,T002,T003
Thallium(Tl)is dispersed element and it seldom occurs in the form of independent minerals.So the element is hard to form any independent deposit.The world annual production of Tl is about 13 ton.most of which is recovered as by-product from non-ferrous metal metallurgical products.Reported in this paper is the only large-sized independent tl deposit in the world,of which the tl ores can be mined,ore-dressed and smelted independently.Bio-enrichment and hydrothermal reworking are the two important metallogenic mechanisms of this Tl deposit.This paper will give a discussion to the Lanmuchang Tl deposit in the following respects including its geolgical characteristics,element association of Tl,Hg,As and Au and W,sulfur isotopic composition.involvement of hallogens in metallogenesis and the metallogenic models.  相似文献   

18.
Based on studies of sequence stratigraphy, event stratigraphy, biostratigraphy and lithostratigraphy, it is concluded that the Sailinhudong Group is a part of the Bayan Obo Group. Some trilobite fragments are first found in thin sections of the rock from the lower part of the Sailinhudong Group and some Ordovician acritarchs and chitinozoans are also found in this group. A formationa unit of carbonate seismites is first recognized in the upper part and a huge micrite mound is first identified at the top. Dolomite, the host rock of the super giant Bayan Obo Fe-Nb-REE deposits, is neither an igneous carbonatite nor a common bedded sedimentary carbonate, but a huge micrite mound. It has the same macroscopic characters as the micrite mounds at the top of the Sailinhudong Group, which suggests that they should be of the same horizon. According to the fossils, the Sailinhudong and Bayan Obo Groups should be of the Early Palaeozoic rather than the Middle Proterozoic. The new discovery and new idea will throw l  相似文献   

19.
Development of Geological Data Warehouse   总被引:2,自引:0,他引:2  
Data warehouse (DW), a new technology invented in 1990s, is more useful for integrating and analyzing massive data than traditional database. Its application in geology field can be divided into 3 phrases: 1992-1996, commercial data warehouse (CDW) appeared; 1996-1999, geological data warehouse (GDW) appeared and the geologists or geographers realized the importance of DW and began the studies on it, but the practical DW still followed the framework of DB; 2000 to present, geological data warehouse grows, and the theory of geo-spatial data warehouse (GSDW) has been developed but the research in geological area is still deficient except that in geography. Although some developments of GDW have been made, its core still follows the CDW-organizing data by time and brings about 3 problems: difficult to integrate the geological data, for the data feature more space than time; hard to store the massive data in fifferent levels due to the same reason; hardly support the spatial analysis if the data are organized by time as CDW does. So the GDW should be redesigned by organizing data by scale in order to store mass data in different levels and synthesize the data in different granularities, and choosing space control points to replace the former time control points so as to integrate different types of data by the method of storing one type data as one layer and then to superpose the layers. In addition, data cube, a wide used technology in CDW, will be no use in GDW, for the causality among the geological data is not so obvious as commercial data, as the data are the mixed result of many complex rules, and their analysis needs the special geological methods and software; on the other hand, data cube for mass and complex geo-data will devour too much store space to be practical. On this point, the main purpose of GDW may be fit for data integration unlike CDW for data analysis.  相似文献   

20.
It is evident that active Zn, Cu, Mo and substituted Mn will be gradually inereasing with time after loess is reclaimed into Dazhai farmland. The effective content of Zn has shown a remarkeble inerease even after a planting season within a year‘s time.The effective contents of Zn, Cu, Mn Mo, B deerease from top to bottom in the soil sections in Dazhai farms. The reverse tendeney is only true for active Zn in Some newly built farm bloeks. This may be due to the deficient supply of Zn in the newly built Dashai fields, and, therefore, good results may be expected if Zn fertilizer is used in a proper way.  相似文献   

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