Gross thickness

The isochore thickness of the total interval ( gross thickness ) "egardless of lithology. 

Connecting the measured points will result in a curve describing the area - depth relationship of the top of fhe reservoir. If we know the gross thickness (H) from logs we can establish a second curve representing the area - depth plot for the base of the reservoir. The area between the two lines will equal the volume of rock between the two markers. The area above the OWC is the oil bearing GRV. The other parameters to calculate STOIIP can be taken as averages from our petrophysical evaluation (see Section 5.4.). Note that this method assumes that the reservoir thickness is constant across the whole field. If this is not a reasonable approximation, then the method is not applicable, and an alternative such as the area - thickness method must be used (see below). 

This is the method used by the commercial software packages Crystal Ball and RISK . The method is ideally suited to computers as the description of the method will reveal. Suppose we are trying to combine two independent variables, say gross reservoir thickness and net-to-gross ratio (the ratio of the net sand thickness to the gross thickness of the reservoir section) which need to be multiplied to produce a net sand thickness. We have described the two variables as follows ... 

Resulting net thickness of heads is both net and gross thickness if one piece seamless heads are used, otherwise net thickness must be corrected to gross thickness as above. 

The subtle part is separated from the gross, thick, and terrestrial part. It is generally performed by passing the liquid through a linen cloth, or by some similar means. 

It has become clear from the use of such a strategy, that some old dogmas, such as the assumption that seal capacity increases with top seal thickness and that faults smaller than the gross thickness of a seal do not represent a seal risk, are unrealistic and misleading, and should be avoided. 

The inadequacy of lateral diffusive mixing is particularly acute in thin reservoirs that have filled in only the past few million years, which is often the case in Tertiary deltas, for example. By contrast, petroleum may mix effectively by vertical diffusion in reservoirs with large gross thicknesses that have had relatively long filling times (Fig. 11b). An example of the latter configuration is the Fahud Field in Oman, where oil analyses show very similar molecular... 

Permeability, md Net Thickness, ft Gross Thickness, ft Irreducible Water Sat., % Residual Oil Sat., % Reservoir Temperature, T... 

In nearly all oil or gas reservoirs there are layers which do not contain, or will not produce reservoir fluids. These layers may have no porosity or limited permeability and are generally defined as non reservoir intervals. The thickness of productive (net) reservoir rock within the total (gross) reservoir thickness is termed the net-to-gross or N/G ratio. 

Keywords deterministic methods, STOllP, GllP, reserves, ultimate recovery, net oil sands, area-depth and area-thickness methods, gross rock volume, expectation curves, probability of excedence curves, uncertainty, probability of success, annual reporting requirements, Monte-Carlo simulation, parametric method... 

GRV is the gross rock volume of the hydrocarbon-bearing interval and is the product of the area (A) containing hydrocarbons and the interval thickness (H), hence... 

A random number (between 0 and 1) is picked, and the associated value of gross reservoir thickness (T) is read from within the range described by the above distribution. The value of T close to the mean will be randomly sampled more frequently than those values away from the mean. The same process is repeated (using a different random number) for the net-to-gross ratio (N/G). The two values are multiplied to obtain one value of net sand thickness. This is repeated some 1,000-10,000 times, with each outcome being equally likely. The outcomes are used to generate a distribution of values of net sand thickness. This can be performed simultaneously for more than two variables. 

Resulting net thickness must be corrected to gross or actual thickness by dividing by joint efficiency. 

Formulas 5 and 6 must often be modified to comply with various engineering codes, and state and municipal regulations. Calculated gross plate thicknesses are sometimes arbitrarily increased to provide an additional allowance for corrosion. 

The anode seal which closes the sodium compartment is a nickel—chromium alloy (Inconel 600). The application of Inconel 600 minimizes the growth of thick inter-metallics and it was shown that seals of this material have been operated for over three years. Contrarily to Inconel, the application of mild steel as the anode seal material gave a life of only 6000 h due to gross intermetallic growth which caused sodium attack of this intermetallic layer in the mild steel. 

The thicker the specimen, the longer it takes for penetration to be complete. A 1-mm thick piece of tissue will take a certain length of time to become penetrated. A 2-mm piece of the same tissue will take four times as long (double squared), and a 3-mm piece will take nine times as long (triple squared). For very thick gross specimens, complete penetration may not occur in any reasonable period of time. If you want very rapid fixation and processing, specimen thickness must be kept as thin as possible. 

Anthropometric measurements are gross measurements of body cell mass used to evaluate LBM and fat stores. The most common measurements are weight, height, limb size (e.g., skinfold thickness and midarm muscle, wrist, and waist circumferences), and bioelectrical impedance analysis (BIA). 

A dent may be defined as a depression that produces a gross disturbance in the curvature of the pipe wall (as opposed to a scratch or gouge, which reduces the pipe wall thickness). The depth of a dent shall be measured as the gap between the lowest point of the dent and a prolongation of the original contour of the pipe in any direction. 

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