库水浸泡后滑坡体中水分布的实验研究

建立了室内模拟库水浸泡后滑坡体内水润湿的渗流实验装置,根据清江茅坪滑坡的地形、地貌以及岩土混合比例,填制了岩土体实验模型.模拟了水位在涨至模拟坡体凌空面一半高度和水位漫过凌空面达到第一平台高度时,坡体内的水分布情况.在水位降落实验过程中,岩土体部分失稳,证明了润湿滞后在降水期滑坡中起主要作用.

夏玉米低定额畦灌田间试验研究

为了合理利用水资源,探索实现低定额均匀灌溉的适宜方法和技术路线,设计作物高效用水的有限灌溉制度,在陕西省杨凌区中壤土玉米地开展了不同畦田规格和灌水定额对土壤水分及玉米产量影响的田间试验。结果表明:对于田面坡度一定的试验田块,入畦单宽流量在3～6lm/s范围内,畦田宽度在4m以内时,各处理小区的土壤平均含水量无显著性差异,但畦田内土壤水分分布却有不同差异,当畦宽2～3m,畦长50m时可达到较高灌水效率(Ea>80%)和灌水均匀度(DU>80%);玉米拔节-抽雄期的灌水定额处理对玉米的生长存在明显影响;不同灌水定额对作物产量、水分利用效率影响显著。

玉米冠层对喷灌水量的再分配

通过喷灌玉米田间试验,研究了喷灌水经玉米冠层再分配后的分布状况。结果表明:在玉米全生育期,茎秆下流水量占灌水量的均值为44%左右,棵间穿透水量占灌水量的均值为48%左右,冠层截留量在0.8￣2.9mm之间变化。一次灌水中,喷灌水在地表的分布很不均匀,43.2%的灌水量经茎秆下流到根区,在距离茎秆7cm,15cm,25cm和32.5cm处,地表接收的水量占总灌水量的比例分别为18.9%、43.5%、66.9%和84.5%。灌水量、种植密度、株高和叶面积指数等都影响着喷灌水在地表的分布。

滴灌条件下土壤水盐运移特性的研究现状

滴灌条件下的水盐运移特性是寻求开发利用盐碱地和次生盐碱化防治的基础 ,国内外学者对此进行大量研究。在国内外研究成果的基础上 ,综述了滴灌点源入渗影响因素、入渗模型特性、水分分布特征、湿润体浸润形状、湿润锋运移、盐分运移的规律 ,为滴灌点源水盐运移的研究提供依据。

松辽盆地南部岩性油藏成藏模式与分布规律

According to the basic geologic conditions, the paper is directed by the modem oil-gas accumulation theory and petroleum system in which typical oil pools are analyzed and the shape of lithologic trap and geologic factors are pointed out. The process during which oil and gas migrate from source rock to lithologic trap is rebuilt, and the accumulation model of oil pool is set up. With the comprehensive application of seismic geologic and log data and paying attention to the method and technology which is used to distinguish lithologic accumulation. Promising structural-lithofacies zones are got and the distribution rule of various lithologic accumulation is concluded. With making use of the biologic mark compound, different reservoirs are compared. As a result, the oil and gas in HeiDimiao come from Nenjiang Group's source rocks; in SaErTu from QingShenkou Group's and Nenjiang Group's, and in PuTaohua. GaoTaizi and FuYang from QingShankou Group's. According to the development and distribution of effective source rock, oil distribution and the comparison in the south of SongLiao basin, the characteristic of basin structure and reservoir distribution is considered, and then the middle-upper reservoir of SongLiao basin south are divided into two petroleum system and a complex petroleum system. Because of the characteristic of migration and accumulation, two petroleum systems can furtherly be divided into 6-7 sub-petroleum systems,20 sub-petroleum systems in all. As a result of the difference of the migration characteristic, accumulation conditions and the place in the petroleum system, the accumulation degree and accumulation model are different. So three accumulation mechanism and six basic accumulation model of lithologic trap are concluded. The distribution of lithologic pools is highly regular oil and gas around the generation sag distribute on favorable structural-lithofacies zones, the type of lithological pool vary regularly from the core of sandstone block to the upper zone. On the basic of regional structure and sedimentary evolution, main factors which control the form of trap are discovered, and it is the critical factor method which is used to discern the lithologic trap. After lots of exploration, 700km~2 potential trap is distinguished and 18391.86 * 10~4 tons geologic reserves is calculated. Oil-water distribution rule of pinch-out oil pool is put up on plane which is the reservoirs can be divided into four sections. This paper presented the law of distribution of oil and water in updip pinch-out reservoir, that is, hydrocarbon-bearing formation in plane can be divided into four zones: bottom edge water zone, underside oil and water zone, middle pure oil zone and above residual water zone. The site of the first well should be assigned to be middle or above pure oil zone, thus the exploration value of this type of reservoir can be recognized correctly. In accordance with the characteristics of seism and geology of low permeability thin sandstone and mudstone alternation layer, the paper applied a set of reservoir prediction technology, that is: (1)seism multi-parameter model identification; (2) using stratum's absorbing and depleting information to predict reservoir's abnormal hydrocarbon-bearing range. With the analysis of the residual resource potential and the research of two petroleum system and the accumulation model, promising objective zones are predicted scientifically. And main exploration aim is the DaRngZi bore in the west of ChangLin basin, and YingTai-SiFangZi middle-upper assembly in Honggang terrace.

港西地区河流相砂岩油藏剩余油分布研究

The Gangxi oil field has reached a stage of high water production. The reservoir parameters, such as reservoir physical characteristics, pore structure, fluid, have obviously changed. This thesis therefore carries out a study of these parameters that control reservoir characteristics, physical and chemical actions that have taken place within the reservoirs due to fluid injection, subsequent variations of reservoir macroscopic physical features, microscopic pore structures, seepages, and formation fluid properties. This study rebuilds a geologic model for this oil field, establishes a log-interpreting model, proposes a methodology for dealing with large pore channels and remnant oil distribution, and offers a basis for effective excavation of potential oil, recovery planning, and improvement of water-injection techniques. To resolve some concurrent key problems in the process of exploration of the Gangxi area, this thesis carries out a multidisciplinary research into reservoir geology, physical geography, reservoir engineering, and oil-water well testing. Taking sandstone and flow unit as objects, this study establishes a fine geologic model by a quantificational or semi-quantificational approach in order to understand the remnant oil distribution and the reservoir potential, and accordingly proposes a plan for further exploration. By rebuilding a geological model and applying reservoir-engineering methods, such as numerical simulation, this thesis studies the oil-water movement patterns and remnant-oil distribution, and further advances a deployment plan for the necessary adjustments and increase of recoverable reserves. Main achievements of this study are as follows: 1. The Minghazhen Formation in the Gangxi area is featured by medium-sinuosity river deposits, manifesting themselves as a transitional type between typical meandering and braided rivers. The main microfacies are products of main and branch channels, levee, inter-channel overflows and crevasse-splay floodplains. The Guantao Group is dominantly braided river deposit, and microfacies are mainly formed in channel bar, braided channel and overbank. Main lithofacies include conglomerate, sandstone, siltstone and shale, with sandstone facies being the principal type of the reservoir. 2. The reservoir flow unit of the Gangxi area can be divided into three types: Type I is a high-quality heterogeneous seepage unit, mainly distributed in main channel; Type II is a moderate-quality semi-heterogeneous seepage unit, mainly distributed in both main and branch channels, and partly seen within inter-channel overflow microfacies; Type III is a low-quality, relatively strong heterogeneous seepage unit, mainly distributed in inter-channel overflow microfacies and channel flanks. 3. Flow units and sedimentary microfacies have exerted relatively strong controls on the flowing of underground oil-water: (1) injection-production is often effective in the float units of Type I and II, whilst in the same group of injection-production wells, impellent velocity depends on flow unit types and injection-production spacing; (2) The injection-production of Type III flow unit between the injection-production wells of Type I and II flow units, however, are little effective; (3) there can form a seepage shield in composite channels between channels, leading to inefficient injection and production. 4. Mainly types of large-scale remnant-oil distribution are as follows: (1) remnant oil reservoir of Type III flow unit; (2) injection-production well group of remnant oil area of Type III flow unit; (3) remnant oil reservoirs that cannot be controlled by well network, including reservoir featured by injection without production, reservoir characterized by production without injection, and oil reservoir at which no well can arrive; (4) remnant oil area where injection-production system is not complete. 5. Utilizing different methods to deal with different sedimentary types, sub-dividing the columns of up to 900 wells into 76 chronostratigraphic units. Four transitional sandstone types are recognized, and contrast modes of different sandstone facies are summarized Analyzing in details the reservoirs of different quality by deciphering densely spaced well patterns, dividing microscopic facies and flow units, analyzing remnant oil distribution and its effect on injection-production pattern, and the heterogeneity. Theory foundation is therefore provided for further excavation of remnant oil. Re-evaluating well-log data. The understanding of water-flood layers and conductive formations in the Gangxi area have been considerably improved, and the original interpretations of 233 wells have changed by means of double checking. Variations of the reservoirs and the fluid and formation pressures after water injection are analyzed and summarized Studies are carried out of close elements of the reservoirs, fine reservoir types, oil-water distribution patterns, as well as factors controlling oil-gas enrichment. A static geological model and a prediction model of important tracts are established. Remaining recoverable reserves are calculated of all the oil wells and oil-sandstones. It is proposed that injection-production patterns of 348 oil-sandstones should be adjusted according to the analysis of adaptability of all kinds of sandstones in the injection-production wells.