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131.
Geochemistry and petrology of selected coal samples from Sumatra, Kalimantan, Sulawesi, and Papua, Indonesia 总被引:4,自引:1,他引:3
Harvey E. Belkin Susan J. Tewalt James C. Hower J.D. Stucker J.M.K. O'Keefe 《International Journal of Coal Geology》2009,77(3-4):260-268
Indonesia has become the world's largest exporter of thermal coal and is a major supplier to the Asian coal market, particularly as the People's Republic of China is now (2007) and perhaps may remain a net importer of coal. Indonesia has had a long history of coal production, mainly in Sumatra and Kalimantan, but only in the last two decades have government and commercial forces resulted in a remarkable coal boom. A recent assessment of Indonesian coal-bed methane (CBM) potential has motivated active CBM exploration. Most of the coal is Paleogene and Neogene, low to moderate rank and has low ash yield and sulfur (generally < 10 and < 1 wt.%, respectively). Active tectonic and igneous activity has resulted in significant rank increase in some coal basins. Eight coal samples are described that represent the major export and/or resource potential of Sumatra, Kalimantan, Sulawesi, and Papua. Detailed geochemistry, including proximate and ultimate analysis, sulfur forms, and major, minor, and trace element determinations are presented. Organic petrology and vitrinite reflectance data reflect various precursor flora assemblages and rank variations, including sample composites from active igneous and tectonic areas. A comparison of Hazardous Air Pollutants (HAPs) elements abundance with world and US averages show that the Indonesian coals have low combustion pollution potential. 相似文献
132.
煤田火区特征的土地覆盖分类方法
——以乌达煤田火区为例 总被引:1,自引:0,他引:1
土地覆盖变化是土地分析与评价和生态环境变化预测的重要科学基础, 通过精确的土地覆盖分类方法
获取高精度的土地覆盖图是研究煤田火区生态环境变化的必要手段。本文以最大似然法、光谱角度法、面向对象
分类法和基于复合分区的分层分类法进行乌达煤田火区土地覆盖分类的方法研究。研究结果表明, 基于复合分区的
分层分类方法分类精度较高, 总体分类精度为92.97%, kappa 系数为0.9155。该方法通过基于地表热辐射特征、热
异常状况、地貌类型, 以及对生态系统扰动状况等的划分, 减少了地物信息的混淆度, 即通过提 相似文献
133.
The Jurassic Walloon Coal Measures of the Surat Basin in eastern Australia host the continent's most significant coal bed methane resources. Previous studies have interpreted the Walloon Coal Measures within a single depositional facies model encompassing a wholly terrestrial setting. Using a multidisciplinary approach (facies analysis, palynology and wireline logs), the evolution of the Walloon Coal Measures is described within a new chronostratigraphic framework defined by accurate and precise U–Pb tuff dates. Analysis of sedimentary facies indicates that the majority of the Walloon Coal Measures was deposited by relatively small (<300 m wide), low gradient rivers on a poorly‐drained floodplain with numerous small lakes and mires. However, this study also identified some marine‐influenced facies with brackish palynomorphs (notably dinoflagellate cysts) and tidal sedimentary structures. These facies appear to have been deposited in estuaries during times of transgression. The evidence for base level shifts suggests that the coals may not have coevally accumulated with at least some of the thicker sandstones. Palaeogeographic maps for eleven time intervals suggest that rivers drained towards to the south/south‐west and south‐east, as indicated by sandstone percentage and gross unit isopach maps, presumably into proximal estuarine complexes. Marine incursions into the continent probably came from the north and east during times of high eustatic sea level and as precursors to those of the more persistent and extensive transgressions of the Early Cretaceous. A similar multidisciplinary approach should help to elucidate the evolution of other fluviolacustrine systems in other basins and aid in resource prediction. 相似文献
134.
肥城煤田作为国家重要能源基地,开发历史悠久,为我国高速发展的国民经济做出了巨大贡献。但长期开采导致塌陷范围广、深度大、积水严重,生态环境遭受严重破坏,给矿区群众的生产生活带来严重影响。该文总结了目前普及化程度较高的采煤塌陷区治理模式,以此为基础,对肥城市采煤塌陷区按照因地制宜的原则,通过分析研究、归纳得出适应于肥城市采煤塌陷区四种不同的治理模式,分别为:土地复垦治理模式、“渔业+农业”治理模式、生态修复治理模式、综合治理模式,并对四种治理模式进行了阐述分析,对今后肥城市采煤塌陷区治理起到借鉴和指导作用。 相似文献
135.
基于火灾资料和气象资料,利用数理统计方法和百分位法,分析了河南省林区火灾的气候特征及防火关键期高火险日数的月、季气候特征。结果表明,林区火灾次数年际波动较大,主要出现在每年的冬春季(12月次年4月),3月出现的次数最多,2月的次之。火灾峰值主要出现在13-16时。3月高火险日数存在显著增加的线性趋势,12月和1月高火险日数呈现先减少后增加的趋势。2月和4月高火险日数处在偏少的年代际背景下。林区春季高火险日数存在显著增加的线性趋势,在桐柏-大别山林区尤其明显。选取河南省防火关键期各月、季高火险日数与海温、积雪、环流场等130项环流指数的相关关系最好的因子,利用最优子集回归分别建立基于林区内各个气象站点的预测方程。通过回代检验和趋势异常综合评分(Ps),对回归方程预测效果进行检验,结果显示,回代曲线和历史曲线吻合好,表明预测方程预测结果接近实况。 相似文献
136.
D. Prieto Herráez L. Ferragut Canals J. M. Cascón Barbero A. Morillo Rodríguez 《International journal of geographical information science》2017,31(11):2142-2163
??This article discusses the integration of two models, namely, the Physical Forest Fire Spread (PhFFS) and the High Definition Wind Model (HDWM), into a Geographical Information System-based interface. The resulting tool automates data acquisition, preprocesses spatial data, launches the aforementioned models and displays the corresponding results in a unique environment. Our implementation uses the Python language and Esri’s ArcPy library to extend the functionality of ArcMap 10.4. The PhFFS is a simplified 2D physical wildland fire spread model based on conservation equations, with convection and radiation as heat transfer mechanisms. It also includes some 3D effects. The HDWM arises from an asymptotic approximation of the Navier–Stokes equations, and provides a 3D wind velocity field in an air layer above the terrain surface. Both models can be run in standalone or coupled mode. Finally, the simulation of a real fire in Galicia (Spain) confirms that the tool developed is efficient and fully operational. 相似文献
137.
通过对巢湖湖泊沉积岩芯不同粒级炭屑浓度和磁化率等指标变化的研究,揭示了全新世以来的区域火环境变化及人类活动影响。结果表明:① 全新世早期,气候由寒冷干旱向温暖湿润过渡,但仍较为干旱,炭屑浓度也相对略高,火活动比较频繁,地方性和区域性火时有发生;② 全新世中期是最温暖湿润的适宜期,炭屑浓度出现全新世以来的低值,火活动微弱,但在文化兴盛时期炭屑浓度出现峰值,则归因于人类活动的影响;③ 全新世晚期,在气候趋于凉干的环境背景下,人类活动的增强更加剧了火活动的频率和强度,炭屑浓度大幅增加;④ 近200 a炭屑浓度的降低可能与湖区附近已没有足够生物量引起火灾有关。 相似文献
138.
Distribution and environmental impact of coal-mining wastes in Upper Silesia, Poland 总被引:8,自引:0,他引:8
About 50 million tonnes/year of waste rock from coal-mining is generated in the limited area of the thickly populated Upper
Silesian Coal Basin (USCB) in Poland. There are 380 coal-mining waste dumps, including 76 active dump sites covering over
2,000 ha. About 15-16 million tonnes/year of waste rock is being reused for civil engineering purposes in the same area. This
brings about a problem of ground water deterioration by constituents leached from waste rock exposed to atmospheric conditions.
The major factors determining the ground water contamination potential from waste rock are chloride salinity, sulfur content
and acid generation potential. The concept behind the presented studies was to provide data for correct evaluation and prediction
of contaminant release from the waste rock, based on the characterization of coal-mining waste properties, as well as on long-term
laboratory, lysimetric and field studies. The results show that coal-mining waste dumps can be a long-term source of ground
water contamination, lasting for decades and increasing with time. Ground water down-gradient from the disused 15–30-years-old
part of the studied dump displays high and increasing acidification, high TDS, SO4, and the highest, still increasing concentrations of Mn, Fe and Zn. Cost-effective and efficient pollution control measures,
similar to the presented design and construction elements of the dump site, can mitigate the negative environmental impacts.
Received: 3 July 1997 · Accepted: 9 September 1998 相似文献
139.
140.
采取多种手段相结合的研究方法,对山东兖州煤田16号煤层的成煤植物进行了详细的研究。研究了16号煤层中的煤核植物群,还通过孢粉分析及分散角质层的研究,对成煤植物群及其在垂向上的演化进行了细致的研究。结合煤岩光片中煤植体的研究,并对照煤系地层大化石所反映的成煤期前后的植物群面貌恢复了16号煤层的成煤植物群。分析并讨论了上述研究方法在反映成煤植物及其演化方面的作用,认为只有通过这种综合研究才可以较准确地反映成煤植物群面貌及其在成煤过程中的变化。 相似文献