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41.
依托“西部煤炭资源高精度三维地震勘探技术”工程,对晋城矿区进行了旨在提高小断层,小陷落柱探测能力的高密度三维地震勘探。根据面元选择因素及该区地质任务,采用5m×5m网格进行野外数据采集;考虑炮检距、方位角、覆盖次数、排列片横纵比及煤层埋深(350~500m)等因素,采用中点放炮、60道接收,24次覆盖(横向4次,纵向6次)的8线16炮束状观测系统,基岩中激发。原始资料经同一处理流程后,获得5m×5m×1ms、5m×10m×1ms、10m×10m×1ms及2.5m×2.5m×1ms不同单元的三维数据体多个,通过对比可以发现小断层,小陷落柱在其小面元叠加时间剖面、顺层切片及相干切片都有清晰的反映。实例说明,小面元采集技术可以提高对小构造的纵、横向分辨能力,满足山区对三维地震精确勘探的要求。 相似文献
42.
屯兰矿南五采区地形复杂,最大高差达271m,地表大面积为第四系黄土覆盖,激发困难。为探索研究小面元三维地震勘探技术的应用效果。在常规三维地震勘区域内划出1km^2,采用5m×5m小面元进行采集。在地震数据采集过程中,采取了加大激发井深、提高覆盖次数、减小CMP面元网格和加大接收排列等技术措施,做到“四小三高、二中一深、两个等高面”。通过插值、抽线及扩大面元处理。获得2.5m×2.5m×1ms、5m×5m×1ms、5m×10m×1ms、10m×10m×1ms以及不同叠加次数的三维数据体。资料解释工作主要是在5m×5m×1ms、2.5m×2.5m×1ms两个数据体上进行,解释落差大于或等于5m的断层6条,落差3~5m的断层8条;查明长轴直径20~30m的陷落柱4个。30~100m的陷落柱1个,大于100m的陷落柱3个。与相邻区常规三维地震比较,小面元三维地震勘探有利于对小陷落柱、小断层的控制和解释。 相似文献
43.
以流线、流面、汇点的概念为基础,对稳定流双井干扰和直线隔水边界附近涌水量理论公式进行对比分析,提出了二个虚拟界面,其中虚拟界面Ⅰ,运用流线、流面的性质,流线方程等给出证明;虚拟界面Ⅱ则通过半无限条形降落漏斗的分析,应用元流和总流的能量方程得到流量为零,流线为零的平面。在同样条件下,条形无限涌水量是半无限潜含水层涌水量的二倍。应用总流能量方程对三种情况水头损失的分析,解释了这种关系存在的合理性,得出虚拟界面Ⅱ,并以此得出该界面内的最大残余水头计算公式。将基坑降水运用虚拟界面简化为扇形,条形半无限含水层,从而实现单井预测,该方法应用到昊华水泥厂基坑降水中,预测效果理想。 相似文献
44.
本文在解放军土地管理局研制的“军用土地管理信息系统”的基础上,从系统设计和应用的角度出发,明确了系统应包括的基本功能,提出了改进和完善系统的方法。 相似文献
45.
Bo PENG Shurong XIE Meilian XIAO Fucheng WU Zhi SONG 《中国地球化学学报》2006,25(B08):23-24
The Taojiang Mn ore deposit was exploited in the early 1960s, and waste rocks were developed since then. Because the Mn ores were hosted within the metal-enriched black shales (Peng et al., 2004), the continuous mining has led to the exposure of an immense quality of black shales, which might cause serious impacts on environments. The present study deals with this environmental issue with samples from the waste rocks, and from the surrounding soils and surface water. The mineralogy of the waste rock was studied using EMPA, then a large number of elements in all waste rock, soil, and water samples were analyzed at a wide range of concentrations with high accuracy using an Elan6000 ICP-MS machine at Guangzhou Institute of Geochemistry, Chinese Academy of Sciences. The waste rock is composed mostly of black shales, with minor Mn carbonates. Both black shales and Mn carbonates of the waste rock contain many sulfide minerals, mainly pyrite, with minor galena, sphalerite, chalcopyrite, and others. The waste rocks are enriched in many metals including Sc, V, Cr, Co, Ni, Fe, Mn, Cu, Zn, Pb, Th, U, Mo, Sb, Sn, Tl, and others, and the metals are mostly hosted within the sulfides. Weathering of waste rocks might cause emission of the following metals: V, Cd, Ni, Th, U, Mo, Sb, Tl, Sc, Cr, Cu, Zn, Sn, and minor Co, and Pb. The surrounding soils are highly enriched in Cr, Co, Cu, Zn, Mn, Mo, Cd, Tl, and Pb, with the enrichment factors of 2.67.3.8, 7.26, 7.27, 8.2, 5.7, 13, and 5.4, respectively. The element ratios (Rb/Cs, Fe/Mn, Nb/Zr, Hf/Zr, and Ba/Sr) and REE distribution patterns of the soils are similar to those of the waste rocks and bedrocks. 相似文献
46.
Savitri Tripathi Vandana Parth Phani Homeshwari M. Vittal Babu N. Murthy N.N. Sorlie J.E. Govil P.K. 《中国地球化学学报》2006,25(B08):117-118
Permeable Reactive Barrier (PRB) is an emplacement of inert material (s) in the subsurface, designed to intercept a contaminated plume, provides a preferential flow path through the reactive media, and transforms the contaminant into environmentally acceptable forms to attain concentration remediation goals at the discharge of the barrier. The phenomena, which help in remediation within PRB, are adsorption/sorption, precipitation, oxidation/reduction and biodegradation. Various materials like zero-valent iron, zero-valent bi-metals, natural zeolites, organic carbon, fly ash, zeolites, limestone, activated alumina, apatites, etc. have been tried by many researchers to remove organic and inorganic contaminants. In USA, Canada, and many European countries commercial full-scale and pilot scale PRBs are successfully working. The design and installation of full scale PRBs needs laboratory treatability and dynamic flow column experiments? The concept of PRB is being applied to treat contaminated surface water in the Katedan industrial area, Hyderabad, India. National Geophysical Research Institute (NGRI), Hyderabad, India, conducted systematic studies in collaboration with Norwegian Geotechnical Institute (NGI), Norway, to develop PRB technique to decontaminate the surface water pollution due to industrial effluent. A site assessment study in the Katedan Industrial Area, were carried out and water, soil and sediment from the lakes of the area were found to be polluted with high concentrations of heavy metals like As, Pb, Cr, Cd, Ni, etc. Adsorption studies at NGRI with synthetic samples and in-situ industrial effluent using different reactive media for removing contaminants like arsenic, chromium, cadmium, copper, nickel, lead and zinc have been carried out and yielded satisfactory results. The performance of zero-valent iron and limestone is encouraging in removing As, 相似文献
47.
The feasibility of using the more sophisticated weighted least-squares (WLS) model, as opposed to the traditional ordinary least-squares (OLS), in linear regressions of BHT data to estimate the static formation temperatures (SFT) was investigated. The most commonly used analytical methods (line-source; spherical and radial heat flow; and cylindrical heat source) were applied. Error propagation equations were derived to calculate errors in the time function of each method. These errors were combined with the BHT measurement errors to compute weighting factors for applying the WLS. Intercept uncertainties were estimated for all regressions using sets of synthetic and actual borehole logs taken from geothermal and oil applications. SFT computed with the spherical and radial heat flow method were generally greater than those from the other two methods. 相似文献
48.
Subsidence due to peat oxidation and impact on drainage infrastructures in a farmland catchment south of the Venice Lagoon 总被引:1,自引:0,他引:1
Large agricultural areas reclaimed in the past century, south of the Venice Lagoon, have experienced significant land subsidence
due to oxidation of peat organic soils. This has exposed the region to flood hazard particularly during severe storms and
has contributed to increase the marginal management cost of the infrastructures (ditches, levees, pumping stations) designed
to operate the drainage system. Direct measurements and indirect evidence from the channel network suggest a land settlement
between 1.5 and 2 m over the past 70 years. This paper provides an overview of the problem with important information on its
most recent evolution. 相似文献
49.
Surface waves image the top of the Eifel plume 总被引:1,自引:0,他引:1
Jan P. Mathar Joachim R. R. Ritter Wolfgang Friederich 《Geophysical Journal International》2006,164(2):377-382
50.
Gated communities of the Moscow green belt: newly segregated landscapes and the suburban Russian environment 总被引:3,自引:0,他引:3
The transition from the Soviet to the post-Soviet period in and near Moscow manifested itself in increasing production of
segregated space both in the urban core and suburban areas outside of the beltway to accommodate the preferences of the new
Russian business and governmental elite. This paper focuses on the residential single-family housing inside old and new settlements,
which are frequently gated. Approximately 260 of such suburban communities have been developed within 30 km of the beltway
during the past few years, of which a majority have some form of exclusion mechanism in place, typically tall solid fences,
gates, closed-circuit video surveillance and guarded entry checkpoints. The difference in exclusivity varies from the most
exclusive older communities inside Moscow Serebryany Bor enclave and Rublevskoe highway mansions to less exclusive new developments
along Novorizkhskoe and Dmitrovskoe highways. Despite high rates of construction, based on sociological surveys in 2003, only
about 11% of Russia’s upper class claimed to live in such new “cottages,” with the rest owning condos and luxury apartments
in the inner city or older detached homes in villages and small towns. Therefore, not all the needs have been accommodated
and more development is certain to take place. The environmental impact of such developments is profound. Based on preliminary
LANDSAT image analysis, almost 22% of suburban “green belt” forested land within 30 km zone has been converted to new construction
from 1991 to 2001. New construction is now focusing on the remaining fragments of natural vegetation, which will likely lower
air quality and water quality available for the city. Ironically, the new developments advertise themselves as “clean and
green” with massive investments in unnatural landscaping (seeded lawns, exotic shrubs, river and lake shore “improvements”).
This investment highlights the well-known paradox of development in which people move out of town to live near nature, while
destroying the wild nature they come to enjoy.
“We left city for the weekend
It was raining, saw no stars
There were fences everywhere
Our chiefs behind the bars.”
Gennady Shpalikov 相似文献