| The fractured reservoirs in the world are about half of the whole proved-up reserves, and vital to the world's oil and gas production. Along with the quick development of the petroleum exploration and exploitation, and the successive discoveries of the volcanic-rock fractured reservoirs in the world, these special reservoirs are attracting more and more people's high attention. As far as the distribution of the fractured reservoirs is concerned in China, the geologic reserve is comparatively high. Especially, the volcanic-rock fractured reservoirs found in recent years show certain exploitation potential. It can be forecasted that the volcanic-rock reservoirs have extensive exploration and exploitation prospect, and will be significant to petroleum industry of our country.There are still some problems concerning the seepage mechanism and simulation study of the fracture and matrix rock masses in the fractured reservoirs so far. Besides extensively developing mechanism experiments and researches pointing to different real fractured reservoirs, the effects of different rock height, pressure and saturation on recovery factor should also be considered synthetically, and how to effectively use relative permeability curves and capillary pressure curves to consider the imbibitions phenomena. This is the research starting point of this paper.Pointing to the problem as above, according to the complexity of the volcanic-rockfractured bottom-water reservoir, regarding the typical reservoir of our country ------ ShixiCarboniferous volcanic fractured reservoir as research background, and based on the formerachievements, indoor experimental researches, reservoir engineering and numericalsimulation of the reservoir filtration mechanism have been developed and the oil, gas, water three-phase seepage regulation has been expanded and perfected. On this condition, a synthetic three-phase seepage mathematical and numerical model of the volcanic fractured bottom-water reservoir has been advanced and the applied simulation software has been developed. Therefore a set of integrated exploitation forecast theories and methods have beenformed. It is significant to decide the exploitation manner of this kind of reservoir and the ultimate recovery factor, and instructively significant to the development of the same domestic reservoirs.By thorough and careful researches, the achievements of this paper are as follows:1. By means of indoor core imbibitions and physical simulation experiments and researches, with the rock samples of Shixi Carboniferous volcanic reservoir, the filtration mechanism of the volcanic fractured reservoir has been thoroughly researched and the cognition of the filtration rule has been grown.2. Based on the related domestic and overseas literature, the present dynamic model during the fluid displacement course of single rock matrix has been improved and perfected, and the three-phase displacement mechanism between rocks and fractures and variety of effective factors in the course of displacement has been far synthetically analyzed with engineering methods, such as the effects of the geometrical size of rock masses, capillary pressure curves, phase-permeation curves, wettability, wetting order, saturation, saturation history and displacement style, etc to recovery degree, and the relationship between imbibitions recovery factor and time has been studied. The filtration theory of the volcanic fractured reservoir has been far developed and perfected.3. The mechanism of the unstable coning process under the condition of fractured bottom-water reservoir imbibitions has been researched by using engineering methods and oil well practical production status. The effects of the decisive methods of critical output, water-appearing period, perforating positions of vertical wells and horizontal wells of different well types on critical output in bottom-water reservoirs have been studied. The bottom-water coning regulation of the fractured bottom-water reservoir has been developed and...
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