河流成因储层沉积微相与剩余油分布及形成机理研究

Based on the study of fluvial sandstone reservoir in upper of Guantao group in Gudao and Gudong oilfields, this paper first introduces A.D.Miall's(1996a) architectural-element analysis method that was summarized from ground outcrop scale into the reservoir formation research of the study area, more subtly divides sedimentary microfacies and establishes sedimentary model of research area.on this base, this paper summarizes the laws of residual oil distribution of fluvial formation and the control effect of sedimentary microfacies to residual oil distribution, and reveals residual oil formation mechanism. These results have been applied to residual oil production, and the economic effect is good. This paper will be useful for residual oil research and production and enhancement of oil recovery in similar reservoir. The major conclusions of this paper are as follows. 1. Using the architectural-element analysis method to the core data, a interfacial division scheme of the first to the dixth scale is established for the studied fluvial formation. 2.Seven architectural-elements are divided in upper of Guantao group of study area. The sandstone group 5～1+2 of Neogene upper Gutao group belongs to high sinuous fine grain meandering river, and the sandstone group 6 is sandy braided river. 3. Inter layer, the residual oil saturation of "non-main layer" is higher than "main layer", but the residual recoverable reserve of former is larger. Therefore, "main layer" is the main body of residual oil distribution. The upper and middle part of inner layer has lower permeability and strong seeping resistance. Addition to gravity effect in process of driving, its driving efficiency is low; residual oil saturation is high. Because of controlling of inside non-permeable interlayer or sedimentary construction, the residual oil saturation of non-driving or lower driving efficiency position also is high. On plane, the position of high residual oil saturation mostly is at element LV, CS, CH (FF), FF etc, Which has lower porosity and permeability, as well as lens sand-body and sand-body edge that is not controlled by well-net, non-perfect area of injection and production, lower press difference resort area of inter-well diffiuent-line and shelter from fault, local high position of small structure. 4.Microscopic residual oil mainly includes the non-moved oil in the structure of fine pore network, oil in fine pore and path, oil segment in pore and path vertical to flow direction, oil spot or oil film in big pore, residual oil in non-connective pore. 5.The most essential and internal controlling factor of fluvial formation residual oil distribution is sedimentary microfacies. Status of injection and production is the exterior controlling factor of residual oil distribution. 6. The controlling effect of formation sedimentary microfacies to residual oil distribution indicates inter-layer vertical sedimentary facies change in scale of injection and production layer-series, planar sedimentary face change and inner-layer vertical sedimentary rhythm and interbed in single layer to residual oil distribution. 7. It is difficult to clear up the inter-layer difference in scale of injection and production layer-series. The using status of minor layer is not good and its residual oil saturation is high relatively. It is obvious that inter-layer vertical sedimentary facies changes control inter-layer residual oil distribution at the same or similar conditions of injection and production. For fluvial formation, this vertical sedimentary facies change mainly is positive gyration. Namely, from down to top, channel sediment (element CHL, LA) changes into over-bank sediment (element LV, CR, CS). 8. In water-injection developing process of transverse connecting fluvial sandstone oil formation, injection water always comes into channel nearby, and breaks through along channel and orientation of high pressure gradient, does not expand into side of channel until pressure gradient of channel orientation changes into low. It brings about that water-driving status of over-bank sedimentary element formation (LV, CR, CS) is not good, residual oil saturation is high. In non-connective abandoned channel element (CH) formation with channel, because this reverse is difficult to control by injection and production well-series, its using status is not good, even terribly not good, residual oil is enrichment. 9. The rhythm and sedimentary structure, sedimentary facies change in single sand body brings about vertical changes of formation character, growth character of inner layer interbed. These are important factor of controlling and affecting vertical water spread volume and inner layer residual oil forming and distribution in single sand body. Positive rhythm, is the principal part of fluvial sandstone inner layer sedimentary rhythm. Namely, from down to upside, rock grain granularity changes from coarse to fine, seeping ability changes from strong to feebleness. It brings about that water-driving status of inner layer upside is not good, residual oil saturation is high. Inner layer interbed has different degree affecting and controlling effect to seeping of oil and water. Its affecting degree lies on interbed thickness, extending scale, position, and jeted segment of production or injection well. The effect of interbed at upside of oil formation to oil and water seeping is less; the effect of interbed at middle of oil formation to oil and water seeping is more. 10. Indoor experiment and research indicate that wettability, permeability step, vertical permeability, position of Kmax and ratio of oil viscousity and water viscousity all have great effect on the water-driving recovery ratio. 11. Microscopic residual oil distribution is affected and controlled by formation pore network structure, pressure field distribution, and oil characteristic. 12.The residual oil forming mechanism: the over-bank sedimentary element and upper part of a positive rhythm sandstone have fine pore and throat network, permeability is low, displacement pressure of pore and throat is high. The water-driving power usually falls short of displacement pressure that brings about injection water does not spread into these pore and throat network, thereby immovable oil area, namely residual oil, is formed. At underside of channel sedimentary element and positive rhythm sandstone, porosity and permeability is relatively high, connecting degree of pore and throat is high, displacement pressure of pore and throat is low. Thereby injection water is easy to enter into pore and throat, driving oil in them. Because the pore space is irregular, the surface of pore wall is coarse and non-flat. That the oil locate on concave hole of pore wall and the dead angle of pore, and the oil attaches on surface of pore wall by surface tension, are difficult to be peeled off, becoming water-driving residual oil (remaining oil). On the other hand, Because flowing section lessens, flowing resistance increase, action of capillary fore, or seeping speed decreases at process of transfer at pass narrow throat path in the course carried by driving water. The "oil drop", "oil bead", or "oil segment" peeled off by driving water is difficult to carry and to drive out by water at less pressure difference. Thereby they are enclosed in pore to form discontinuous residual oil. 13.This results described above have been applied in nine develop blocks of Gudao and Gudong oilfield. Its applying effect is marked through local injection production adjustment, deploying replacement well, repair hole, replacement envelop, block off water and profile control etc. Relative method and technology can be applied to other oil production area of Shengli oilfield, and obtain better economic and societal effect.

河流-三角洲储层剩余油分布模式及预测

Aim at the variousness and complexity of the spatial distribution of Remaining Oil in the fluvial and delta facies reservoir in paper. For example, in the La-Sa-Xing oilfield of Daqing, based on the research of the control factor and formation mechanization of block, single layer, interlayer and micromechanism, synthesizing the theories and methods of geology, well logging, reservoir engineering, artificial intelligence, physical simulation test , and computer multidisciplinary; Fully utilizing the material of geology, well logging, core well, dynamic monitor of oil and water well, and experimental analysis, from macro to micro, from quality to quantity, from indoor to workplace, we predicted the potentiality and distribution according to the four levels of Block, single layer, interlayer and micromechanism, and comprehensively summarized the different distribution pattern of remaining oil in the fluvial and delta facies reservoir This paper puts forward an efficient method to predict the remaining recoverable reserves by using the water flooding characteristic curve differential method and neutral network; for the first time utilizes multilevel fuzzy comprehensive judgment method and expert neutral network technology to predict the remaining oil distribution in the single layer? comprehensively takes advantage of reservoir flowing unit, indoor physical simulation test, inspection well core analysis and well-logging watered-out layer interpretation to efficiently predict the distribution of remaining oil; makes use of core analysis of different periods and indoor water driving oil test to study the micro distribution of remaining oil and the parameters varying law of reservoir substance properties, rock properties, wetting properties. Based on above, the remaining oil distribution predicting software is developed, which contains four levels of block, single layer, interlayer and micromechanism. This achievement has been used inLa-Sa-Xing oil field of Daqing and good results have been received.

高山峡谷地区大跨度桥梁岸坡稳定性分析、趋势预测及应用研究

In order to realize fast development of the national economy in a healthy way and coordinate progress with whole society, the country has implemented the strategy of development of the western region. An important action of finishing this strategic task is to accelerate the highway construction in the western region, join the western region and places along the coast, the river, the border with goods and materials, technology, and personnel interchanges, and then drive development of the local economy.The western region was influenced by the Himalaya Tectonization in Cenozoic, and the crust rose and became the plateau. In the course of rising, rivers cut down sharply to form a lot of high mountains and gorges.Because of topography and geomorphology, bridges in the traffic construction in the alpine gorge area are needed. Rivers have characteristics of large flow, fast velocity and high and steep river valley, so building a pier in the river is not only very difficult, but also making the cost increase. At the same time, the impact that the pier is corroded and the bridge base that is drawn to be empty by flow are apt to cause destruction of the pier. For those reasons, suspending bridge and cable-stay bridge are usually adopted with the single and large span. For the large span bridge, the pier foundation could receive ten thousand and more vertical strength, bending moment and near kiloton horizontal thrust.Because bank slope in the alpine gorge district is cut deeply and unsettled big, natural stability is worse under endogenic and exogenic force. When bank slope bears heavy vertical strength, bending moment and horizontal thrust facing the river, it will inevitably make the balance state of rock and soil mass change, bridge bank slope deform, and even destroyed. So the key problem at the time of the large span's bridge construction in the alpine gorge area is how to make it stable.So based on the spot investigation, the Engineering Geology Analysis Method is very important to grasp the bank slope stability. It can provide the bank slope stability macroscopic ally and qualitatively, and reference to the indoor calculation. The Engineering Geology Analysis Method is that by way of analyzing and investigating terms of bank slope instability, stability development trend, the ancient rock slide and devolution in the site, stability comprehensive evaluation primarily, current and future stability of bank slope is gotten, realizing the intention to serving the concrete engineering.After the Engineering Geology Analysis Method is applied to project instances of BeiPan River Bridge and BaLin River Bridge, results are accord with bank slope actual conditions, which proves sites are suited to building bridges from site stability.we often meet bank slope stability issues in the traffic construction in the alpine gorge areao Before the evaluation of the bank slope stability, the engineering geological condition is investigated first. After that, the next exploration target and geology measures are decided. So, the Engineering Geology Analysis Method that the investigation of the engineering geological condition is the main content is quite important in practice. The other evaluations of the bank slope stability are based on it. Because foundation receives very heavy load, for the big span's bridge in the alpine gorge area, a long pile of the large diameter (D^0.8m) is usually selected. In order to reflect rock mass's deformation properties under rock-socketed pile function, the author has used the FLAG30 software for rock and soil mass and done many numerical simulations. By them, the author launches the further investigation on deformation properties of bank slope under different slope angle, pile length, diameter, elastic modulus, load, bank slope's structure, etc. Some conclusion meaningful to the design and produce are obtained.