Reserves definition

The critical linkage between financial and accounting considerations and reserve definitions requires an understanding of the definitions given in Securities and Exchange Commission Regulation... 

As defined by the World Petroleum Congress/Society of Petroleum Engineers (modified from Grace, J. D. et al. (1993). "Comparative Reserves Definitions U.S.A., Europe, and the Former Soviet Union." Journal of Petroleum Technology 45(9) 866-872. 

Schuyler, J. (1999). Probabilistic Reserves Definitions, Practices Need Further Refinement. Oil and Gas Journal, May 31. 

Society of Petroleum Engineers (SPE) and World Petroleum Council (WPE) (1997). Petroleum Reserve Definitions. March. 

The area can be measured from a map. Figure 6.1 clarifies some of the reservoir definitions used in reserves estimation. 

An alternative and commonly used representation of the range of reserves is the proven, proven plus probable, and proven plus probable plus possible definition. The exact cumulative probability which these definitions correspond to on the expectation curve... 

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... 

Estimates of the amount of natural gas available are made within the context of definitions and are subject to revision as definitions change, as additional information becomes available, as resources are consumed, or as undedyiag assumptions are altered. These definitions iaclude proved reserves where the resource is expected to be recoverable and marketable usiag known technology and prices probable reserves where a resource has been identified but not completely characterized and possible or potential gas where estimates are based on the available geological iaformation, historical trends, and previous successes. There are variations ia these definitions throughout the world. 

The general definition of a condensation reaction is a one that involves product formation by expulsion of water (or other small molecule) as a by-product. By this definition, activation and methylolation are also condensations. In more precise terms the chain-building process should be described as a condensation polymerization, however, in the jargon of the phenolics industry, the term condensation is usually reserved for the chain-building process. This terminology is not necessarily observed in the literature [88]. Many literature reports correctly refer to methylolation as a condensation reaction. The molecular weight development of the phenol alcohol adducts may also be classified as a step-polymerization. 

Debate continues over just how much natural gas remains in North America. Part of this debate centers on the definition of gas reserves—the amount of gas in a given area that is recoverable and gas resource, the total amount of gas in the ground. Gas production to date, as might be expected, has most commonly been from easy-to-produce conventional... 

There are many definitions of reserves and resources, and we need some historical perspective to understand the current debates. 

Facilitate pre-vulcanisation processing, increase softness, extensibility and flexibility of the vulcanised end-product. The rubber processing industry consumes large quantities of materials which have a plasticising function complex mixtures (paraffinic, naphthenic, aromatic) of mineral hydrocarbon additives, used with the large tonnage natural and synthetic hydrocarbon rubbers, are termed process oils. Because of the complexity of these products, precise chemical definition is usually not attempted. If the inclusion of an oil results in cost reduction it is functioning as an extender. The term plasticiser is commonly reserved for synthetic liquids used with the polar synthetic rubber. 

We have shown that in the monadic case one simple pushdown store suffices. Similar to this definition of the augmentation of a flowchart scheme by a simple pushdown store one can define a counter as a reserved variable u whose values can only be non-negative integers and to which can only be applied the functions u + 1 and u - 1 and the predicate u = 0. As in the case of an added pushdown store, all assignments to or by u must be independent variable - that is u f(v) and v + f(u) are forbidden for v u and any f. ... 

While this definition of electron-pair covalency neglects the effective charges on the bonded atoms, the designation "homopolar bond appears to be reserved for the special case of an electron-pair bond... 

In general, a thermometer is called primary if a theoretical reliable relation exists between a measured quantity (e.g. p in constant volume gas thermometer) and the temperature T. The realization and use of a primary thermometer are extremely difficult tasks reserved to metrological institutes. These difficulties have led to the definition of a practical temperature scale, mainly based on reference fixed points, which mimics, as well as possible, the thermodynamic temperature scale, but is easier to realize and disseminate. The main characteristics of a practical temperature scale are both a good reproducibility and a deviation from the thermodynamic temperature T which can be represented by a smooth function of T. In fact, if the deviation function is not smooth, the use of the practical scale would produce steps in the measured quantities as function of T, using the practical scale. The latter is based on ... 

The reader may prefer to attach a reservation to this definition, making an exception of atoms in which the unpaired electron occupies an inner shell as in transition series elements. 

This chapter will cover the efforts that have been made to use the principles of combinatorial chemistry in the development of new catalysts. In the last few years there has been a lively discussion of what is the correct definition of combinatorial chemistry. Some workers reserve the term combinatorial chemistry for the synthesis and evaluation of mixtures. For the purpose of this chapter, we will employ a liberal interpretation of the term. Since one of the definitions of the word combinatorial is, of or involving combinations (14), we will use the term to include what may be referred to as parallel synthesis. In parallel synthesis, one generates a combination of molecules, be they in separate vials or on separate pins. One view may be that a collection of vessels represents a combination of molecules. It is for this... 

The assessment and quantification of the remaining reserves and resources of fossil fuels is a very complex and broad field, characterised by a lack of internationally harmonised definitions and standards, great data uncertainties and discrepancies and, consequently, the potential danger of data abuse for political purposes. Within the scope of this publication, only an overview of the range of the currently available estimates of fossil resources is provided and the focus is rather on the general discussion of potential sources of uncertainty, than on a detailed assessment of the different methodological and statistical approaches and discrepancies at country or even field level. 

There is also no single, commonly accepted technical definition of (proved) reserves, and in the above definition many words are ambiguous and without any quantification a major drawback of the deterministic approach. 

In the SPE/WPC scheme, reserves are classified according to the probability with which they can be produced into proved , probable and possible reserves. Under these definitions, proved reserves are those with a probability of at least 90% (P90) that the estimated volumes can be produced profitably proved plus probable reserves are required to have at least 50% probability (P50), while proved plus probable plus possible reserves are based on a probability of at least 10% (P10). 

Table 3.2 shows the remaining potential (the sum of reserves and resources) of conventional oil at the end of 2005, which amounts to around 1800 Gb, made up of 1200 Gb reserves and 600 Gb resources. In line with the definition in Section 3.3.1, these figures do not include unconventional oil, such as crude bitumen from oil sands production in Canada or extra heavy oil from Venezuela.11 Almost three-quarters of... 

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