Net to gross ratio

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 ... 

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. 

The purpose of this exercise is to identify what parameters need to be further investigated if the current range of uncertainty in reserves is too great to commit to a development. In this example, the engineer may recommend more appraisal wells or better definition seismic to reduce the uncertainty in the reservoir area and the net-to-gross ratio, plus a more detailed study of the development mechanism to refine the understanding of the recovery factor. Afluid properties study to reduce uncertainty in (linked to the shrinkage... 

Fault seal probability analysis is a quantitative method that allows an assessment of the risk of a fault acting either as a barrier to hydrocarbon migration, or as a trapping element within a structure. Fault seal probability is a value ranging from one to zero where a value of one is the highest probability for sealing, and zero is the lowest. This value is derived from the equation that combines the main parameters involved in the formation of fault seal. These parameters, fault displacement, connectivity, and net to gross ratio, are related to the processes of cataclasis and cementation, juxtaposition, and shale smear. The parameters, their measurement and impact on fault seal, are discussed below. 

The last variable to be included in the fault seal probability equation is the net to gross ratio. The assumptions used in the formulation of the equation are that with low net to gross ratios, say <0.4, there is a greater likelihood for sealing due to shale smear than in higher net to gross ratio successions (see also Bou-vier et al., 1989 Harding and Tuminas, 1989). 

Well Name Interval (ft) Weighted Mean Effective Porosity %) Weighted Mean Water Saturation (%) Net Pay Thickness (ft) Net to Gross Ratio... 

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. 

Table 14.5 lists the ratio of net to gross calorific values for various fuels. 

The ratio of net contact to gross tread surface area decreases as wet traction becomes more important. Tables 14.3 and 14.4 illustrate the net-to-gross percentage for various tire tread patterns. 

Air-to-cloth ratio The unit capacity of a fabric filter, i.e., the total volume of gas in actual m Vs divided by the gross or net fabric area in m. ... 

The high hydrogen/carbon ratio of gas means that the quantity of water vapor in the products of combustion is greater than most other fossil fuels. The latent heat of this cannot be released in conventional appliances leading to a low net/gross ratio of calorific value of 90 per cent. (It is normal practice to quote gross CV in Europe net CV is often used. If net CV is quoted, efficiencies of over 190 per cent are possible.)... 

Dolomite cementation has had a minuscule impact on the net/gross ratio in the studied sand body, but will have severely partitioned it in terms of potential fluid throughflow. Preservation of the dolomite and lack of reddening, in contrast to other formerly ferroan dolomite-cemented sandstones in... 

The use of gross calorific values or net calorific values (which assume that the water of combustion is present as vapour) plus the assumed value of coal leads to different coal to oil ratios being quoted in the literature, e.g. 1.5 1 to 1.7 1 by different authorities ". The composition of natural gas varies widely in different parts of the world leading to different calorific values. North Sea gas contains about 90% methane and has a typical calorific value of 52 GJ per tonne. 

Figure 5.4 Gross-section strain as a function of diameter-to-width ratio in the bearing and net-section regions.

This paper focuses on C2C and four other finance performance metrics revenue change rate (%), profit margin (%, net and gross), ROA (%), and current ratio. With the data from the selected industries, a comparison of the C2C of each industry has been conducted. This was then the correlation analysis of the C2C and finance performance metrics to see whether there is a positive or negative relationship between them. 

Finally, a point to clarify is that a ratio may have more than one name, but mean the same thing. It is common to hear the words earnings, income, and profit, which are all synonymous. It is important to understand what is being referred to exactly. To make matters worse, when profits are used, is the term referring to gross profit, operating profit, or net profit In short, accurate ratio analysis requires clarity so that comparisons can be made. The items mentioned in this section should all be considered when analyzing ratios because they can create confusion. 

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