Reservoir permeability

In high permeability reservoirs, wells may produce dry oil for a limited time following a shut-in period, during which gravity forces have segregated oil and water near the wellbore. In fields with more production potential than production capacity, wells can be alternately produced and shut in (intermittentproduction) to reduce the field water cut. This may still be an attractive option at reduced rates very late in field life, if redundant facilities can be decommissioned to reduce operating costs. 

Conventional gas is natural gas occurring in a normal porous and permeable reservoir rock, either in the gaseous phase or dissolved in crude oil, and recoverable by normal technical production practices. 

R. D. Gdansk . Huid properties and particle size requirements for effective acid fluid-loss control. In Proceedings Volume, pages 81-94. SPE Rocky Mountain Reg Mtg/Low Permeability Reservoirs Symp (Denver, CO, 4/26-4/28), 1993. 

P. S. Northrop. Imbibition process using a horizontal well for oil production from low permeability reservoirs. Patent US 5411094,... 

R.A., Jr. "High Efficiency Fracturing Fluids for High-Temperature, Low-Permeability Reservoirs", SPE/DOE paper 11615, 1983 SPE/DOE Symposium on Low Permeability, Denver, March 14-16. 

Roodhart, L.P. Davies, D.R. "Polymer Emulsion The Revival of a Fracturing Fluid , SPE/DOE paper 16413, 1987 SPE/DOE Low Permeability Reservoirs Symposium, Denver, May 18-19. 

Anderson, M.S. Fredrickson, S.E. "Dynamic Etching Tests Aid Fracture Acidizing Treatment Design," SPE/DOE paper 16452, 1987 SPE/DOE Low Permeability Reservoirs Sumposium, Denver. 

Holcomb, D.L. "Low Concentration Hydrochloric-Hydrofluoric Acid Mixtures for Stimulation in Low Porosity, Low Permeability Sandstone Formations," Proc. Svmp. Stimul, Low Permeability Reservoirs.1976. 72-86, Colo. Sch. Mines, Golden. 

Properties and extraction processes Tight-formation gas is natural gas trapped in low-porosity (7 to 12%), low-permeability reservoirs with an average in-situ permeability of less than 0.1 millidarcy (mD), regardless of the type of the reservoir rock tight gas usually comprises gas from tight sands (i.e., from sandstone or limestone reservoirs) and shale gas. Sometimes tight gas also comprises natural gas from coal and deep gas from reservoirs below 4500 m. Shale gas is produced from reservoirs predominantly composed of shale rather than from more conventional sandstone or limestone reservoirs a particularity of shale gas is that gas shales are often... 

Weak Cel Application in a Low-Permeability Reservoir Generally, weak gel is applied in high-permeability or fractured reservoirs. This target application was used in the Hong-Shan-Zui held of Karamay Oilfield,... 

When a layered reservoir has high permeabihty contrast in vertically different layers, polymer can be injected through separate layers to control the injection profile, as mentioned previously. Another method is alternate injection of polymers with different molecular weights (MW). As discussed in Section 5.4.4, high MW polymer can be used in a high-permeability reservoir, and low MW polymer must be used in a low-permeability reservoir. For the alternate injection, the layers are grouped into different permeability layers high, intermediate, and low. 

This chapter covers the fundamentals of surfactant flooding, which include microemulsion properties, phase behavior, interfacial tension, capillary desaturation, surfactant adsorption and retention, and relative permeabilities in surfactant flooding. It provides the basic theories for surfactant flooding and presents new concepts and views about capillary number (trapping number), relative permeabilities, two-phase approximation of the microemulsion phase behavior, and interfacial tension. This chapter also presents an experimental study of surfactant flooding in a low-permeability reservoir. 

Generally, chemical flooding is conducted in a high permeability reservoir. This section describes an experimental study of the application of surfactant flooding... 

Chen, T.-R, Pu, C.-S., 2006. Study on ultralow interfadal tension chemical flooding in low permeability reservoirs. Journal of Xi an Shiyou University 21 (3), 30-33. 

The petroleum is not free in underground cavities but enclosed within the permeable reservoir rocks. It is zoned with gas and water into layers, according to the specific gravities. The gas is usually at the top, petroleum in the middle and the salt water in the lower layer. 

Larsen, T. I. Pileharvi, A. A. Azar, J. J. Presented at the SPE Rocky Mountain Region/Low Permeability Reservoirs Symposium, Denver, CO, April 1993 paper SPE 25872. 

Stiles, D. A. Baret, J. F. Presented at the Rocky Mountain Regional/Low Permeability Reservoirs Symposium of the Society of Petroleum Engineers, Denver, CO, April 12-14, 1993 paper SPE 25866. 

Law, B. E. Dickinson, W. W. 1985. A conceptual model for the origin of abnormally pressured gas accumulations in low-permeability reservoirs. American Association of Petroleum Geologists Bulletin, 69, 1295-1304. 

Chinese Journal of Rock Mechanics and Engineering. 19(1) pp. 971-975 Liu J.J., Liu X.G., Hu Y.R. 2002. Study on Fluid Flow through Low permeability reservoir. Chinese Journal of Rock Mechanics and Engineering. 21(1) pp. 48-54 Zhou W.Y. 1993. Advanced Rock Mechanics. 

Knoll, S. Presented at the Society of Petroleum Engineers-Department of Energy Symposium on Low-Permeability Reservoirs, Denver, CO, 1985 paper no. 13904. 

Until now, no one investigated the recovery fact gh permeability reservoirs of... 

Most of the remaining oil reserves present in the Miocene strata of the Krasnodar Petroliferous Region are concentrated in reservoirs with poor permeability. Special experimental studies were therefore carried out to find an efficient method of increasing the oil recovery factor of these low permeability reservoirs. Models of two different kinds of porous media and of different gas factors were used in these experiments. 

At the start of production from oil fields of this heterogeneous nature, crude oil is held both in the reservoirs of micro- and of macroporosity types. The permeability of type I reservoir ranges from 100 to 200 millidarcies, and the permeability of type II reservoir, from 500 to over 1,000 Darcies. Because of this large difference in values, the high permeability reservoirs of type II,... 

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