Reservoir description

The section is divided into four parts, which discuss the common reservoir types from a geological viewpoint, the fluids which are contained within the reservoir, the principal methods of data gathering and the ways in which this data is interpreted. Each section is introduced by pointing out its commercial relevance. 

Keywords reservoir structures, faults, folds, depositional environments, diagenesis, geological controls, porosity, permeability 

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Explain how the term reservoir description is applied to characterizing a homogeneous floe system. 

It is of interest in a reservoir simulation study to compute future production levels of the history matched reservoir under alternative depletion plans. In addition, the sensitivity of the anticipated performance to different reservoir descriptions is also evaluated. Such studies contribute towards assessing the risk associated with a particular depletion plan. 

The minimum and maximum total oil production rates for the rlh reservoir description are given by... 

RESERVOIR DESCRIPTION. The TFSA-waterflood pilot study was conducted in Santa Fe Energy Company s Torrance Field. The field was discovered in 1922 and produces from Miocene and Pliocene sands located at depths of 3100 ft to 4400 ft (945 m to 1340 m) subsea. Within the pilot area, the net pay thickness of the Main Zone averages 96 ft (29 m) and varies from less than 90 ft (27 m) in the center of the pattern to more than 110 ft (34 m) in the northwest and southeast sections of the pilot. 

Do not attempt to compare fluid types as defined here with the reservoir descriptions as defined by the state regulatory agencies which have jurisdiction over the petroleum industry. The legal and regulatory definitions of oil, crude oil, gas, natural gas, condensate, etc., usually do not bear any relationship to the engineering definitions given here. In fact, the regulatory definitions are often contradictory. 

Example Nitrate Loadings in a Drinking Water Reservoir -Description of the Problem... 

Reservoir Description Key to Success in Chemical-Enhanced Oil Recovery... 

Chemical enhanced oil recovery processes are now in a period of retrenchment caused mainly by less than successful performance of several field tests. Nearly all of these tests have, to at least some extent, been affected by shortcomings in the reservoir description which compound process complexities and uncertainties. 

Surprises in the reservoir description should be regarded as normal in EOR applications however, we can do a far better job of anticipating by adopting an integrated approach to reservoir simulation based on geology, statistics and fluid flow modeling known as conditional simulation. 

LAKE Reservoir Description in Chemical-Enhanced Oil Recoveiy... 

Karlsen D. A. and Latter S. (1990) A rapid correlation method for petroleum population mapping within individual petroleum reservoirs apphcations to petroleum reservoir description. In Correlation in Hydrocarbon Exploration (ed. J. D. Collinson). Norwegian Petroleum Society, Graham and Trotman, pp. 75-85. 

Reservoir Reservoir description Reservoir size (mole P X 10 ) Reference Residence time T(yr)... 

Seggie, R.J., Lansom, P.B., Hamlin, H.S. Johnson, G.A. (1994) The Tirrawarra oil field field revitalisation through reservoir description and characterisation. Aust. Petrol. Explor. Asj. /, 34, 33-54. 

Masterson, W. D. Paris, C. E. 1987. Depositional history and reservoir description of the Kuparuk River Formation, North Slope, Alaska. In Tail-LEUR, I. Weimer, P. (eds) Alaskan North Slope Geology. Pacific Section SEPM The Alaska Geological Society, Bakersfield Anchorage, 95-107. 

Fig. 1. Simple reservoir description used in analysis of fluid mixing. The porosity and permeability are homogeneously distributed.

Fig. 5. Simple reservoir geometry used for modelling fluid pressure equilibration. Note that this geometry can be unzipped along the centre of the shale and opened out to give a model that is topologically equivalent to a cross section through the base reservoir description shown in Figure 1. Symbols described in Table 1, apart from h (shale thickness) and / (shale gap length).

Fig. 13. Model predictions of API gravities of oils in a West African Tertiary delta with several stacked reservoirs, colour-coded green, blue and red, compared with data. (The closely spaced and overlapping dots show the modelled trends in the reservoirs, each dot corresponding to increments of oil charge that entered the trap in successive small time steps, whereas the squares arc the data.) Because of the simplified reservoir description in the model, it is only possible to compare the general characteristics of the modelled and observed distributions of API gravity.

Wadman, D. H., Lamprecht, D. E. Mrosovsky, I. 1979. Reservoir description through joint geologic-engineering analysis. Society of Petroleum Engineers, Paper No. 7531. 

Karlsen, D. a. Larter, S. R. 1991. Analysis of petroleum fractions by TLC-FID Applications to petroleum reservoir description. Organic Geochemistry, 17, 603—617. 

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