Formation factor

F = formation factor R = formation water resistivity R = true resistivity of the formation... 

Drilling and Well Completions Calculate the formation factor using... 

The presence of particles in the fluid medium complicates diffusion in a sediment due to the effects of porosity, represented by n, and tortuosity. Since tortuosity of natural sediments is seldom known it is more convenient to use the term "formation factor" or "lithological factor," denoted L, which takes into account everything but porosity. Tick s diffusion constant D is replaced by the whole sediment diffusion constant Ds, where < D. 

The maximum value for the tortousity was 30 and the value for the tortusity of each sample was estimated from the formation factor. The formation factor was taken either from resistivity measurents or estimated from NMR measurements and the Myers pore-combination model [37]. A comparison of the estimated permeability correlations is given in Figure 3.6.9. The SDR model overestimates the permeability of low permeability samples and the Chang model underestimates the permeability of high permeability samples. The modified Chang model, Eq. (3.6.9), improves the estimate of permeability for both low and high permeability samples. 

Classification3 Minimum Apparent Thickness, cm Formation Factor (F), cm Capillary Fringe Height,b cm U.S. Standard Sieve Size Rang... 

Cooney. R. V., Ross, P.D., Bartolini, G.L., and Ramseyer, J. IV-Nitrosamine and IV-nitroamine formation factors influencing the aqueous reachons of nitrogen dioxide with morpholine. Environ. Sci. Technol, 21 (l) 77-83,1987. 

Figure 2. Relative significance of the zeolite formation factors...

If relative total volumes, BlD, are reported as a part of the results of the differential vaporization, total formation factors can be calculated as... 

The oil formation factor can be calculated using the results of ideal-solution calculations of the liquid density at reservoir conditions. 

We have now demonstrated that both the FDSP and FDE responses are dependent on the capillary/pore dimension. Once the pore dimension is known this can applied to an appropriate permeability model to obtain more information about the porous media. Using an appropriate permeability model along with formation factor measurements we can estimate the permeability of porous samples. Alternatively, if we measure the permeability of a sample we can then use the permeability model to determine the formation factor and tortuosity of the sample using measurements that are base on the hydraulic properties and not the electrical properties. This is currently a work in progress to compare formation factor measurements made using the two methods. 

The reciprocal of

[Pg.24]

Figure 2 denotes these constraints and the location of the optimum, when Fcf (coke formation factor of the feed) - 0.1. 

Samples used in this study, their formation, petrographic, petrophysical and mineralogical characteristics. C crystal carbonate M-W mudstone, wackestone P-G packstone-grainstone Vac vugs iX intercrystalline pores iM intramatrix pores iG intragranular pores IG intergranular pores K karsts Fr fractures F formation factor m cementation factor n saturation exponent. 

The second is the model proposed by Johnson, Schwarty and co-workers who introduced a dynamic length scale Ae which is a function of the electrical field intensity E in the medium and is related to the formation factor and so to Archie s exponent m by the relationship [12] ... 

Fig. 5 Chargeability factor A/can be predicted by a Fig. 6 Permeability prediction from electrical multi-linear model composed by different behaviour and structures parameters of porous parameters formation factor F, water porosity O, solids, k Katz and Thompson model Hg-specific surface Asp and water permeability k for kjsc Johnson, Schwartz and co-workers different textures. model.

Well logging Electrical surveys resistivity conductivity shale formation factor salinity variations Interval transit time Bulk density Hydrogen index Thermal neutron capture cross section Nuclear magnetic resonance Downhole gravity data After drilling... 

Thickness Thickness increases over time The thickest varnishes grow in wetter micropositions that foster erosion of the underlying weathering rind or on spalled fracture faces. Thus, although varnish does thicken over time if all other formation factors are held constant, the thinnest varnishes can be the oldest at any given site... 

Table 1.1 Relative dielectric constant en anodic formation factor m, density p, band gap energy Eg, cation transfer coefficient t + f bias dependence and electronic behavior (SC = semiconductor), structure (a = amorphous, c = crystalline), texture dependence for some of the oxide systems described in this treatise (see also [20]). 

This equation defines the oxide formation factor m (nm V ), that is, the layer thickness increases linearly with the applied potential. 

Figure 1.31 Model for the texture dependent oxide growth on Zr surfaces. The crystallographic orientation angles of substrate Zr and oxide film Zr02 are given in addition to the electrochemically (photoresist method) determined formation factors [17].

Figure 1.35 Zr02 film orientation angle and oxide formation factor as a function of the Zr substrate orientation [17].

Figure 1.37 (a) Coulometrically determined film thickness and film formation charge as a function of the formation potential. Determination of formation factor, ca. 2nmV-1. (b) Reciprocal capacitance and film thickness as a function of formation charge for determination of the relative dielectric constant er= 16 [103],... 

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