Reservoir compartmentalization

Understanding the rate at which fluids move and mix in the subsurface is crucial for correctly interpreting reservoir geochemical data, and is particularly important for extracting business value from such data. One of the main ways in which reservoir fluid data (here including fluid pressure, fluid physical properties, fluid chemical properties and fluid contacts) are applied is in the detection of reservoir compartmentalization, something that is key for optimizing reservoir development. 

The majority of past studies of reservoir compartmentalization have not considered mixing rates this often resulted in a yes it is or no it is not interpretation of compartmentalization. However, in nature most scenarios are not simply black or white. The question should thus not be whether or not the reservoir is com-... 

If more than one type of data is available, this process can be used for each data type. If the data reflect processes with different rates, then the simultaneous interpretation of the full dataset should fiuther constrain the degree of reservoir compartmentalization. If a field is known, or can reasonably assumed, to be compartmentalized... 

Edman, J. D. Burk, M. K. 1999. Geochemistry in an integrated study of reservoir compartmentalization at Ewing Bank 873, offshore Gulf of Mexico. Society of Petroleum Engineers, Reservoir Engineering and Evaluation, 2, 520-526. 

Smalley, P. C. Hale N. A. 1996. Early identification of reservoir compartmentalization by combining a range of conventional and novel data types. Society of Petroleum Engineers, Formation Evaluation, September 19%, 163-169. 

OilTracers L. L. C. 2002. Assessing reservoir compartmentalization using oil geochemistry. WWW. oiltracers.com... 

Smalley, P. C. England, W. A. 1992. Assessing reservoir compartmentalization during field appraisal how geochemistry can help. Society of Petroleum Engineers, Paper No. 25005. 

Evidence of reservoir compartmentalization by calcite cement layers in deepwater sandstones, Bell Canyon Formation, Delaware Basin, Texas... 

Parnell, I, Middleton, D., Chen, H.H., Hall, D. (2001) The nse of integrated fluid inclusion studies in constraining oil charge history and reservoir compartmentation examples from the Jeanne d Arc Basin, offshore... 

The Tambaredjo field prodnces from the Paleocene age Saramacca formation. These coastal plain sandstones are locally identified as the T-unit and were deposited on top of a Cretaceous unconformity. The sands pinch out updip, south of the field, providing stratigraphic traps for the oil. The pilot area, located in the Tambaredjo field, has imdergone very little structural deformation and minimal diagenesis since the deposition of the Paleocene T-reservoirs consequently the sediments are relatively unconsolidated. This type of sedimentary processes of coastal plain deposition resnlted in reservoir compartmentalization, which is demonstrated by the pressure distribution along the area. 

The sediment reservoir (1) represents all phosphorus in particulate form on the Earth s crust that is (1) not in the upper 60 cm of the soil and (2) not mineable. This includes unconsolidated marine and fresh water sediments and all sedimentary, metamorphic and volcanic rocks. The reason for this choice of compartmentalization has already been discussed. In particulate form, P is not readily available for utilization by plants. The upper 60 cm of the soil system represents the portion of the particulate P that can be transported relatively quickly to other reservoirs or solubilized by biological uptake. The sediment reservoir, on the other hand, represents the particulate P that is transported primarily on geologic time scales. 

Fig. 39.14. (a) Catenary compartmental model representing a reservoir (r), absorption (a) and plasma (p) compartments and the elimination (e) pool. The contents X, Xa, Xp and X,. are functions of time t. (b) The same catenary model is represented in the form of a flow diagram using the Laplace transforms Xr, Xa and Xp in the j-domain. The nodes of the flow diagram represent the compartments, the boxes contain the transfer functions between compartments [1 ]. (c) Flow diagram of the lumped system consisting of the reservoir (r), and the absorption (a) and plasma (p) compartments. The lumped transfer function is the product of all the transfer functions in the individual links. 

There is no clear evidence of major faults within the Sm0rbukk reservoir (Heum et al., 1986), and pressure barriers within the same formation appear not to be structurally controlled (Ehrenberg et al., 1992). It is therefore possible that compartmentalization to a large extent is due to progressive burial diagenesis of sandstones and siltstones, particularly in the Tilje Formation which may have lateral facies variations. 

The mechanism of the competitive pertraction system (CPS) is presented schematically in Fig. 5.4 together with the compartmental model necessary for constructing the reaction-diffusion network. The simple flat-layered bulk liquid membrane of the thickness En and interface area S separates the two reservoirs (f, feed and s, stripping) containing transported divalent cations A2+ and B2+ (most frequently Zn2+ and Cu2+ or Ca2+ and Mg2+) and/or antiported univalent cations H+. At any time of pertraction t, their concentrations are [A]f, [B]f, and [H]f and [A]s, [Bj, and [H]s, for the feed and stripping solution, respectively. The hydrophobic liquid membrane contains a carrier of total concentration [C]. Its main property is the ability to react reversibly with cations at respective reaction zone and to diffuse throughout the liquid membrane phase. 

Type 3 and some type 1 tabular units are often laterally extensive, in some cases extending for over 2 km (see Fig. 7). These units would form significant barriers to vertical fluid flow, perhaps resulting in compartmentalization of the reservoir/aquifer. Such compartmentalization can result in dramatically reduced production if wells are screened on... 

Fracturing and fault compartmentalization of sandstones fundamentally affects reservoir properties and may significantly influence the fluid migration pathways in a basin (Knipe, 1993). Open fractures may form high-permeability conduits, whereas cement-sealed fractures form barriers to fluid flow. Seismic, petrophysical and reservoir performance data allow regional (field-scale) effects of faulting on fluid flow to be constrained. However, much fracturing and associated cementation may occur at sub-... 

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