930 resultados para Source and sink
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On the basis of accelerator mass spectrometer radiocarbon (AMS C-14) dating, sedimentation rates of 11 cores collected from the northern to southern Okinawa Trough are discussed. The sedimentation rates in the Okinawa Trough roughly range from 11 to 39 cm/ka, and the average is 23.0 cm/ka. China's continental matter is the main sediment source of the middle Okinawa Trough and has important contribution to the northern and southern Okinawa Trough. The sedimentation rates during the marine oxygen isotope (MI5) 2 are uniformly higher than those during MIS 1 in the northern and middle Okinawa Trough while they are on the contrary in the southern Okinawa Trough. Sedimentation rates in the Okinawa Trough can be one of the proxies of sediment source and an indicator of cooling events.
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Manganese abnormity has been observed in the Holocene sediments of the mud area of Bohai Sea. On the basis of grain size, chemical composition, heavy mineral content and accelerator mass spectrometry (AMS) C-14 dating of foraminifer, relationships between manganese abnormity and sedimentation rates, material source, hydrodynamic conditions are probed. Manganese abnormity occurred during the Middle Holocene when sea level and sedimentation rates were higher than those at present. Sedimentary hiatus was not observed when material sources and hydrodynamic conditions were quite similar. Compared with the former period, the latter period showed a decrease in reduction environment and an inclination toward oxidation environment with high manganese content, whereas provenance and hydrodynamic conditions showed only a slight change. From the above observations, it can be concluded that correlation among manganese abnormity, material source, and hydrodynamic conditions is not obvious. Redox environment seems to be the key factor for manganese enrichment, which is mainly related to marine authigenic process.
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From systemic research of microstructure, geochemistry, uranium-series and Be-10 isotope dating on a new-type deepwater ferromanganese crust from the East Philippine Sea, the paleoenvironment evolution of the target area since the terminal Late Miocene was recovered. The vertical section changes of microstructure and chemical composition are consistent in the studied crust, which indicate three major accretion periods and corresponding paleoenvironment evolution of the crust. The bottom crust zone was formed in the terminal Late Miocene (5.6 Ma) with loose microstructure, high detritus content and high growth rate. Reductions of mineral element content, accretion rate and positive Ce-anomaly degree at 4.6 Ma indicate temporal warming, which went against the crust accretion and finally formed an accretion gap in the terminal Middle Pliocene (2.8-2.7 Ma). The more active Antarctic bottom seawaters in the Late Pliocene (2.7 Ma) facilitated the fast transfer to the top pure crust zone. Hereafter, with the further apart of volcanic source and the keeping increase of eolian material (1.0 Ma), although surrounding conditions were still favorable, mineral element content still shows an obvious reducing trend. It thereby offers new carrier and data for the unclear paleoceanographic research of the target area since the terminal Late Miocene.
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铜管一直是电厂凝汽器的主要应用管材,但由于其抗冲刷和抵御污染物腐蚀的能力差,特别不耐氨蚀,美国和欧洲大量使用不锈钢管替代铜管作为冷凝管,然而不锈钢管在我国的运用仅处于初步阶段。 常使用锌、铝阳极对铜管进行牺牲阳极保护,然而存在着电位差过大、阳极溶解过快的问题。铁基牺牲阳极与铜电位差适当、来源广泛、价格便宜,在一些工程上有所应用,但是目前针对铁基牺牲阳极的理论研究报道很少。 本文选用紫铜管、304不锈钢管作为实验用管材,首先运用实验室全浸实验、极化曲线和电化学阻抗研究了二者在海水和淡水中的腐蚀性能以及CO2、溶解氧对其腐蚀的影响。结果表明:CO2会加速二者的腐蚀,溶解氧却对它们的腐蚀影响不同,促进铜管的腐蚀却抑制不锈钢管的腐蚀;随浸泡时间的延长,紫铜管由于表面产物膜的生成耐蚀性提高,304不锈钢管的耐蚀性却降低;淡水中,304不锈钢管和紫铜管都具有很好的耐蚀性能。随后,运用失重法和极化曲线对比研究了紫铜管、304不锈钢管的氨蚀性能,运用SEM分析和电化学阻抗研究了紫铜在不同浓度氨溶液中的腐蚀机理。发现,304不锈钢管的耐氨蚀能力远远好于铜管;溶解氧是影响氨蚀的关键因素,其对二者氨蚀的影响也不同;紫铜管在低氨浓度和高氨浓度溶液中腐蚀机理和产物不同,低氨浓度时形成保护性的产物膜(CuO 和Cu(OH)2),高氨浓度时由活化溶解控制,生成可溶的[Cu (NH3)4]2+。 选用工业纯铁、35钢为牺牲阳极材料。恒电流实验结果表明它们具有良好的牺牲阳极性能;通过极化曲线和自腐蚀电位测试分析,认为将二者用于铜管牺牲阳极保护是可行的;实验室阴极保护效果测试表明,工业纯铁和35钢对紫铜管具有良好的保护效果,保护度达90%以上。
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沉积物由源到汇的搬运过程是整个地球物质循环的一个重要环节;在这一过 程中,载有当时主要地质历史事件信息的沉积物汇入海洋;但因受到复杂的海洋 环境的改造以及人类活动的影响,这些信息的表现形式可能已经发生了改变。因 此,如何反演上述地质历史进程、预测其发展变化,成为海洋地质学研究的重要 内容。 本文通过对长江、黄河、钱塘江、瓯江和闽江等5 条中国东部入海河流沉积 物稀土元素(REE),以及东海陆架表层细颗粒沉积物中粘土矿物、元素组成等 的综合研究,借助数学统计,分析探讨了陆架区细颗粒沉积的物质来源、现代长 江入海沉积物在东海陆架区的影响范围,以及由源到汇输运过程中沉积物示踪标 记数值改变等问题。 长江口沉积物REE 在<2μm 和2-31μm 粒级中较富集,但全岩REE 总量 (ΣREE)在数值上受物质组成占优的2-31μm 粒级控制;因粉砂对水动力环境的 反映最为敏感,在输运过程中该粒级组成不稳定即可引起全岩REE 含量的变化。 全岩REE 含量在河口附近较高,在东海陆架区由岸向海有减小的趋势,轻重稀 土比值自28°N 向南有增大的趋势。在长江口和东海内陆架,水动力对沉积物的 作用可能对REE 含量空间分布模式的形成起着重要作用。 长江、黄河等五条河流沉积物的ΣREE、轻重稀土含量比值(L/HREE)等 参数在数值分布上有所不同。但陆架复杂的水动力环境可造成砂粒级沉积物中轻 重矿物分异、粉砂与粘土粒级间级配调整,并由此引起沉积物中REE 含量的数 值变化。此时,单由砂、粉砂等较大粒级区间内REE 含量的分布已经不能准确 判断沉积物物源的改变。在长期稳定的陆架沉积环境下,借助沉积物输运模型, 有可能解决因水动力因素造成的REE 分布变化的问题。 东海陆架区未能发现在数值上绝对不变的示踪标记物,而引起示踪指标变化 的决定性因素尚未明确。因此,本文采用前人研究中可以明显区分沉积物河流来 源的指标,借助统计学中聚类和判别分析方法定性地判断东海陆架区沉积物常、 微量元素和粘土矿物的可能物源。 根据四种主要粘土矿物相对含量与细颗粒沉积物微量元素的构成特征,推断 研究区表层类长江细颗粒物质主要为现代长江入海沉积物;它们主要分布在东海陆架中、西部区域,在中部可以跨越123°E 向东继续延伸,在北部可以达到外陆 架的东部边缘。研究区东侧、东海外陆架边缘表层细颗粒沉积物的微量元素构成 与现代长江沉积物存在较大差异,具有类黄河沉积物的性质,可能是在更新世冰 期干冷气候下形成的产物与现代河流入海细颗粒的混合物。
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A suitable method for the pretreutment of dissolved nitrate samples in seawaters for nitrogen isotopic analysis was established. First, the seawater samples were processed by removing nitrite and amonium. Then Devard's alloy was added in sample for conversion of dissolved nitrate to ammonium. The sample was distilled, and then the ammonium condensate was collected with zeolite. after distillation, the collected condensate was filtered and prepared for determining nitropic values. Some tests of the method were conducted. The distillation condition, the influence of salinity on nitrogen isotopic analysis, absorption of ammonium onto zeolite and an improved method on a large volume of seawater were discussed in this study. The results showed that the distillation step had an average recovery of (104.9 +/- 4.2) % (n = 6) when distillating every 300 mL aliquot of the sample under a strong alkaline condition with 0.5 g devard's alloy and a distillation time of 30 min. The nitrogen isotopic fractionation decreased markedly when salinity was increased from 0% to 0.5%; further increase(1% - 3.5%) showed little effect. The adsorption rate of ammonium onto zeolite had a high yield of (95.96 +/- 1.08) % (n = 6) in average. An improved collection method was used to process a large volume of seawater with several distillations, and had good effect on analysis. The method had been applied to analyze water samples collected from Changjiang estuary. The analytical results indicate that the method is suitable for delta N-15 analysis of dissolved nitrate in seawaters. The present method could provide valuable information about the source and cycle mechanism of dissolved nitrogen in estuary waters.
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The source and significance. of two mitrients, nitrogen. and phosphorous, were investigated by a modified dilution method performed on seawater samples from the Jiaozhou Bay in autumn 2004. This modified dilution method accounted for the phytoplankton growth rate, microzooplankton grazing mortality rate, the external nutrient pools, as well as nutrient supplied through remineralization by microzooplankton. The results indicated that the phytoplankton net growth rate increased in turn from inside the bay, to outside the bay, to in the Xiaogang Harbor. The phytoplankton, maximum growth rates and microzooplankton grazing mortality rates were 1.14 and 0.92 d(-1) outside the bay, 0.42 and 0.32 d(-1) inside the bay and 0.98 and 0.62 d(-1) in the harbor respectively. Outside the bay, the remineralized nitrogen (K-r = 24.49) had heavy influence on the growth of the phytoplankton. Inside the bay, the remineralized phosphorus(K-r = 3.49) strongly affected the phytoplankton growth. In the harbor, the remineralized phosphorus (K-r = 3.73) was in larger demand by phytoplankton growth. The results demonstrated that the different nutrients pools supplied for phytoplankton growth were greatly in accordance with the phytoplankton community structure, microzooplankton grazing mortality rates and environmental conditions. It is revealed that, nutrient remineralization is much more important for the phytoplankton growth in the Jiaozhou Bay than previously believed.
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激光诱导击穿光谱技术(LIBS)具有无需样品制备,原位快速分析,可进行实时控制的特点使其在钢铁冶炼控制中具有巨大的实际应用价值。本文以波长为1 064 nm的Nd∶YAG调Q固体激光器为激发光源,CCD为探测器,高合金钢GBW01605—01609系列为样品,在建立的LIBS实验装置上研究激光与合金钢之间的相互作用。系统地研究了观测距离、激光能量对高合金钢样品中激光诱导击穿谱特性的影响,并分析了LIBS信号的时间分辨特性,确定了将LIBS用于合金钢微量元素定量分析时的最佳实验条件。
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本文介绍用光学阵列传感器的机器人物体分类系统。传感器直接安装在机器人的两个手指上。被抓物体的阴影通过光导纤维传到安放在“安全区”的光敏元件上。计算机识别物体的轮廓后命令机器人抓握物体,并把它运送到指定的地点从而达到物体分类的目的。
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结合车轮沙土相互作用的力学分析,研究解决轮式移动机器人沙地行驶车轮过度滑转下陷问题。考虑纵列式重复通过车轮沙土力学参数的修正,建立六轮式沙地移动机器人的动力学模型,以车轮滑转率为状态变量,设计了移动机器人沙地行驶的滑模驱动控制器跟踪车轮期望滑转率。MATLAB/Simulink仿真结果表明,采用该控制器可以较快地跟踪期望滑转率,有效地限制机器人车轮的滑转,避免车轮的过度下陷。
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Sandstone-type uranium deposits are frequently found close to oil fields or uraniferous sandstones contain bitumen or petroleum. However, few evidence has been presented to indicate the association of uranium mineralization with petroleum oxidation. Thus, Dongsheng uranium deposit in Ordos Basin and Qianjiadian deposit in Kailu Basin are taken for examples to solve the puzzle. Integration data from sedimentary petrology, mineralogy, race elements geochemistry, isotope geochemistry and organic geochemistry, the uranium and petroleum sources, and diagenetic paragenesis of the host sandstone are analyzed, and then the genetic relationship between microbes, petroleum and uranium deposits are discussed. The observation under microscope shows that the host sandstone samples from Middle Jurassic Zhiluo Formation in the Dongsheng deposit contained different kinds of metamorphic rock fragments, which should have been derived form outcrops north to this basin. The LREE/HREE ratios of gneiss and amphibolite sampled from outcrops were close to the highest and the lowest LREE/HREE ratios of the sandstones with well-compared chondrite-normalized REE patterns, respectively. So these results consistently indicated that parent rocks of sandstones were mainly contributed from these two kinds of metamorphic rocks. There was very high Th/U ratio for granite gneiss, which was a mainly potential U resource. Hydrocarbon inclusions and adsorbed hydrocarbons are observed under fluorescence microscope in the host sandstone of Dongsheng uranium deposit, suggesting that the sandstones may have been utilized as oil migration pathways. Based on biomarker parameters, it is indicated that the inclusion oils and adsorbed hydrocarbons were marginally mature to mature, and were derived from humic-sapropel type organic matter under poor reducing freshwater to semi-saline environment. The features are similar to those of organic matter extracted from Triassic sandstone and source rock, but are different from that of cretaceous sandstone. Thus, it can be concluded that the inclusion oils and adsorbed hydrocarbons were mainly derived from Triassic lacustrine facies source rock. Observation results under Scanning Electron Microscopy and Electron Microprobe with Energy Spectrum Analysis show that, in Dongsheng area, the main uranium ore mineral is coffinite. The coffinite is intimately intergrown or coexists with pyrite and calcite, thus, the solution during mineralization stage is inferred to be alkaline. The alkaline environment is not favored for uranium to be pre-concentrated by absorption, and then be reduced abiogenetically. δ34S of pyrite and δ13C of calcite indicate that pyrite was formed by bacterial sulfate reduction (BSR) and part of the carbon of calcite has been dirived from oxidation of petroleum, respectively. Additionally, petroleum is found biodegraded. All the lines of evidence consistently indicate that petroleum was involved in uranium mineralization. Coffinite with microbe-like structures is found in the high U sandstone samples and is composed of nanoparticles, indicating the coffinite is biogenic. The conclusion are also supportted by laboratory experiment studies, which have shown that SRB are capable of utilizing U(VI) as the preferred electron acceptor for respiration and reduce U(VI) to U(IV) directly, coupled the oxidaton of organic matter and sulfate reduction. Based on the research results mentioned above, in the Dongsheng area, coffinite is likely to have formed by mixing of brine containing petroleum derived from Triassic with uranium-bearing meteoric water from outcrops north to Ordos Basin. SRB utilize hydrocarbon as carbon source, and directly reduce U(VI) resulting in precipitation of coffinite. The product of metabolism, H2S and CO2, was precipitated as pyrite and calcite during mineralization stage. Petroleum in fluid inclusions and adsorbed type in host sandstone from Lower Cretaceous Yaojia Formation in Qianjiadian uranium deposit, Kailu Basin, are derived from Jurassic Jiufotang Formation in this basin and the uranium mineral consists mainly of pitchblende. The δ34S and δ13C values of pyrite and calcite during mineralization stage indicate SRB have likely degraded petroleum, which is similar to that of Dongsheng deposit. The alkaline environment as indicated by the diagenetic mineral assemblage calcite, Fe dolomite, pyrite and pitchblende deposit suggests that U ore in the Qiangjiajiadian has a similar origin, i.e., direct reduction by SRB. However, less part of pitchblende is intergrown with kaolinite, suggesting the solution during mineralization stage is acidic. The environment is favorable for U(VI) to be adsorded on quartz or other mineral, and then reduced by H2S produced by SRB. Thus, it can be concluded that U(VI) reduction with petroleum oxidation by SRB and other microbes is an important ore-forming mechanism in petroleum-related sandstone-type uranium deposits. The finding is significant in that it provides a theoretical basis for exploration of both uranium and petroleumr.
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Seismic signal is a typical non-stationary signal, whose frequency is continuously changing with time and is determined by the bandwidth of seismic source and the absorption characteristic of the media underground. The most interesting target of seismic signal’s processing and explaining is to know about the local frequency’s abrupt changing with the time, since this kind of abrupt changing is indicating the changing of the physical attributes of the media underground. As to the seismic signal’s instantaneous attributes taken from time-frequency domain, the key target is to search a effective, non-negative and fast algorithm time-frequency distribution, and transform the seismic signal into this time-frequency domain to get its instantaneous power spectrum density, and then use the process of weighted adding and average etc. to get the instantaneous attributes of seismic signal. Time-frequency analysis as a powerful tool to deal with time variant non-stationary signal is becoming a hot researching spot of modern signal processing, and also is an important method to make seismic signal’s attributes analysis. This kind of method provides joint distribution message about time domain and frequency domain, and it clearly plots the correlation of signal’s frequency changing with the time. The spectrum decomposition technique makes seismic signal’s resolving rate reach its theoretical level, and by the method of all frequency scanning and imaging the three dimensional seismic data in frequency domain, it improves and promotes the resolving abilities of seismic signal vs. geological abnormal objects. Matching pursuits method is an important way to realize signal’s self-adaptive decomposition. Its main thought is that any signal can be expressed by a series of time-frequency atoms’ linear composition. By decomposition the signal within an over completed library, the time-frequency atoms which stand for the signal itself are selected neatly and self-adaptively according to the signal’s characteristics. This method has excellent sparse decomposition characteristics, and is widely used in signal de-noising, signal coding and pattern recognizing processing and is also adaptive to seismic signal’s decomposition and attributes analysis. This paper takes matching pursuits method as the key research object. As introducing the principle and implementation techniques of matching pursuits method systematically, it researches deeply the pivotal problems of atom type’s selection, the atom dictionary’s discrete, and the most matching atom’s searching algorithm, and at the same time, applying this matching pursuits method into seismic signal’s processing by picking-up correlative instantaneous messages from time-frequency analysis and spectrum decomposition to the seismic signal. Based on the research of the theory and its correlative model examination of the adaptively signal decomposition with matching pursuit method, this paper proposes a fast optimal matching time-frequency atom’s searching algorithm aimed at seismic signal’s decomposition by frequency-dominated pursuit method and this makes the MP method pertinence to seismic signal’s processing. Upon the research of optimal Gabor atom’s fast searching and matching algorithm, this paper proposes global optimal searching method using Simulated Annealing Algorithm, Genetic Algorithm and composed Simulated Annealing and Genetic Algorithm, so as to provide another way to implement fast matching pursuit method. At the same time, aimed at the characteristics of seismic signal, this paper proposes a fast matching atom’s searching algorithm by means of designating the max energy points of complex seismic signal, searching for the most optimal atom in the neighbor area of these points according to its instantaneous frequency and instantaneous phase, and this promotes the calculating efficiency of seismic signal’s matching pursuit algorithm. According to these methods proposed above, this paper implements them by programmed calculation, compares them with some open algorithm and proves this paper’s conclusions. It also testifies the active results of various methods by the processing of actual signals. The problems need to be solved further and the aftertime researching targets are as follows: continuously seeking for more efficient fast matching pursuit algorithm and expanding its application range, and also study the actual usage of matching pursuit method.
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Maichen Depression lie between Leizhou Peninsula and Qiongzhou Strait. Oil and gas have been discovered in Weixinan Depression, Wushi Depression and Fushan Depression, which pertain to a same basin — North Sea Basin along with Maichen Depression.Jiangsu Oil started exploration at 2002. The first well began to drill at November, 2004 after gravity survey, electric method prospecting and 2D seismic exploration had been finished. Generating rock and hydrocarbon shows have been verified by the drilling. Low yield oil stream has been tested. And we started 3D seismic exploration at November, 2005. My thesis topic came from the actual needs of our exploration in the Maichen Depression. In the thesis, I give emphasis to analyse the own seismic geologic conditions of Maichen Depression. By real tests, we choosed the means to overcome or weaken the unfavorably impress owing to the own coditions in Maichen Depression. Finally, we obtained the usable seismic data. 1. Owing to the multiphase eruptive rock during the Quaternary Period, the near surface layers are very inhomogeneous. By simultaneous testing at same point with short refraction, uphole surveys of radial source and of surface source, the most appropriate method had been sorted out. Radial source uphole survey has been regarding the best practicable means in the complex area. Accurate surficial geology was very helpful to choosing of acquirement means and parameters. Basically the appropriate method of seismic acquirement has been built at Maichen area. 2. The seismic primary data has many, very strong and complex noise. By noise characteristic analysis in different domain, many means of denoising had been paralleled individual and joint application researched. As a result, the pre-stack multidomain joint denoise flow was the appropriate method. It can improve the seismic signal-to-noise ratio. 3. The problem of seismic static correction at Maichen Depression is very conspicuous. Many static correction methods had been tested individual and joint researched. The seismic data quality has been improved after choosing the appropriate combination of static correction flows. 4. Although the above-mentioned process are resultful, the seismic profile quality is just passable. Some reflector continuity and fault zone imagery are ambiguity. So it was the useful method to reduce the structural ambiguity during seismic interpretation that built-up geologic model in accord with real geologic character by areal structure study upon backbone seismic profiles. In the same way, traps have been assessed and drill targets have been selected.
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Complex fault block reservoir is very important type in chinese oilfield.The reservoir have for many years and it has been the important issue of oil-gas exploration and development in china that how to increase reserves and production. Therefore,taking the Pucheng-oil field as an example, the article intensive study the geologic feature of oil pool, correctly recognize the rule of oil-gas accumulation and based on the fine representation of the characteristic of reservoir, research the remaining oil in high developed area,which is important for progressive exploratioon and development and taping the remaining oil. The article multipurpose uses the data of geology,drilling,wellloging, analysis and assay and so on, under the guidance multi-disciplinary theory, intensify the comprehension of the geologic feature of oil pool in high developed oil field. Based on the high-resolution sequence stratigraphic framework ,the article points out that Es_2 upper 2+3 reservoir in the south area of Pucheng oilfield is in the depositional environment of Terminal Fan, which has constant supply of sedimentary source ,and build the sedimentation model. Studies have shown that the major reservoir in work area is the distributary channel sandbody in central Sub-facies of Terminal Fan,secondary is both lateral accretion sandbodies of channel sands,nearby and far away from the channel overflowing sandbodies in front of the fan. The article analyze the effect of depth of burial of the reservoir, sandstone structure, strata pressure and bioturbate structure on control action of physical property for reservoir and indicate that deposition and diagenesis are major controlling factors.By building the model of reservoir heterogeneity, the article show the magnitude of reservoir heterogeneity ,the genesis and identification mark of Interlayer and build the the model of interlayer. in this area the vertical distribution of interlayer is complicated,but the intraed interlayer distribute steady. Thick interlayer is steady and the thin is relatively spreaded. By building models of fault sealing,stress field and fluid potential field of the south of the pucheng oil field, the regular pattern of fluid migration and accumulation runs out. By researching the elements of oil accumulation, migration pathway and accumulation period with quantification and semiquantitative methods,we bulit the oil-gas reservoir-forming mode of the south of the pucheng oil field,which will be the foundation of the rolling exploratory development in the future. We promulgated the master control element and the rule of distribution of the remaining oil with the upside 2+3 oil layer in shaer in the south of the pucheng oil field as an example.In this area, the formation and the distribution of the remaining oil is controled by the sedimentary microfacies, reservoir heterogeneity,fault and reservoir engineering. The remaining oil is concentrated in the vicinity of the gas cap, updip of the fault block and the area with incomplete flooding. Remaining oil saturation in some area can get 50%, so there are many places in which we can enhance oil recovery.
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Acoustic Gravity waves (AGW) play an important role in balancing the atmospheric energy and momentum budget. Propagation of gravity wave in the atmosphere is one of the important factors of changing middle and upper atmosphere and ionosphere. The purpose of this dissertation is to study the propagation of gravity wave in a compression atmosphere whit means of numerical simulation and to analyze the response of middle and upper atmosphere to pulse disturbance from lower atmosphere. This work begins with the establishment of 2-D fully nonlinear compressible atmospheric dynamic model in polar coordinate, which is used ton numerically study gravity wave propagation. Then the propagation characteristics of acoustic gravity wave packets are investigated and discussed. We also simulate the response of middle and upper atmosphere to pulse disturbance of lower atmosphere in background winds or without background winds by using this model and analyze the data we obtained by using Fourier Transform (FT), Short-time Fourier Transform (STFT) and Empirical Mode Decomposition (EMD) method which is an important part of Hilbert-Huang Transform (HHT). The research content is summarized in the following: 1. By using a two-dimensional full-implicit-continuous-Eulerian (FICE) scheme and taking the atmospheric basic motion equations as the governing equations, a numerical model for nonlinear propagation of acoustic gravity wave disturbance in two-dimensional polar coordinates is solved. 2. Then the propagation characteristics of acoustic gravity wave packets are investigated and discussed. Results of numerical simulation show that the acoustic gravity wave packets propagate steadily upward and keep its shape well after several periods. 3. We simulate the response of middle and upper atmosphere to pulse disturbance of lower atmosphere in background winds or without background winds by using this model, and obtain the distribution of a certain physical quantity in time and space from earth’s surface to 300km above. The results reveal that the response of ionosphere occurs at a large horizontal distance from the source and the disturbance becomes greater with increasing of height. The situation when the direction of the background wind is opposite to or the same as the direction of disturbed velocity of gravity-wave is studied. The results show that gravity wave propagating against winds is easier than those propagating along winds and the background wind can accelerate gravity wave propagation. Just upon the source, an acoustic wave component with period of 6 min can be found. These images of simulation are similar to observations of the total electron content (TEC) disturbances caused by the great Sumatra-Andaman earthquake on December 26 in 2004. 4. Using the EMD method the disturbed velocity data of a certain physical quantity in time and space can be decomposed into a series of intrinsic mode function (IMF) and a trend mode respectively. The results of EMD reveal impact of the gravity wave frequency under the background winds.