1 Scope
This standard specifies the applicability, definitions, classification, categories and codification for the Chinese "Classification for Resources/Reserves of Solid Fuels and Mineral Commodities".
This standard is applicable to the engineering, work deployment, reserve (resource) computation and report preparation as well as to the assessment, registration and statistics of solid fuels and mineral resources/reserves, development of planning, policies on solid fuels and mineral resources, specifications, codes and guidelines for mineral exploration, and may serve as the basis for the assessment and computation of mineral resources/reserves involved in activities, e.g. assignment of mining right, financing for mineral exploration and exploitation.
2 Definitions
For the purposes of this standard, the following definitions apply.
2.1 Solid fuels and mineral resources: are defined as naturally occurring solid concentrations of economic interest formed in earth crust or on surface due to geological actions. Basing on their output forms, quantities and quality, the final exploitation may be expected to be of technological feasibility and economic soundness. Their locations, quantities, grade/quality and geological characters are computed and estimated according to specific geological bases and knowledge. According to the geological assurance, they may be divided into the total identified mineral resources and undiscovered resources.
2.1.1 Total identified mineral resources: are defined as the total solid fuels and mineral resources discovered by exploration and according to the different results acquired from their degree of geological assurance and feasibility assessment, may be subdivided into three categories as the extractable reserves, basic reserves and resources.
2.1.2 Undiscovered resources: are defined as the solid fuels and mineral resources which are not justified by geological bases and geophysical and geochemical abnormality prospection.
2.2 Mineral exploration can be divided into four consecutive stages which are: reconnaissance, prospecting, general exploration and detailed exploration.
2.2.1 Reconnaissance: it identifies areas of enhanced mineral potential on a regional scale based primarily on results of regional geological studies, geophysical and geochemical abnormality study, preliminary field inspection, as well as few quantity demonstration results, analogy with known deposits of similar geological character and prospection. Estimates of resource quantities, which belong to the undiscovered, should be made if sufficient data are available.
2.2.2 Prospecting: it is to roughly find out the brief geology and structure, deposit forms, occurrence, quality characters, technical conditions for deposit mining of the regions to be prospected of enhanced mineralization potential and of geophysical and geochemical abnormalities, using outcrop identification, geological mapping, quantity-limited sampling and geophysical and geochemical studies, with an analogy study carried out for the processing performance of minerals. It shall finalize if it is worthy of further general exploration or shall narrow down the areas for general exploration.
2.2.3 General exploration: it is to basically find out the geological features, structure, shape, occurrence, size and ore quality of the major deposit, deposit continuity, technical conditions for deposit mining, by subjecting the areas narrowed down for general exploration during the prospecting to large-scale geological mapping and various exploration methods and means, systematic sampling more intensive than the prospecting stage. Either by carrying out an analogy of the processing performance of ore or by mineralogical tests on laboratory scale, it shall give an assessment on its industrial value and if necessary, narrow down the area for detailed exploration, and may serve for the prefeasibility study, overall planning and project proposal for mining. As for mining areas available for direct exploitation and utilization, the degree of the processing performance test shall reach the requirements sufficient for mine construction and engineering.
2.2.4 Detailed exploration: it is to definitely find out the geological features of deposit, deposit shape, occurrence, size, spatial location and ore quality characters, technical conditions for mining by subjecting the deposit known to be of industrial value or the area for detailed exploration narrowed down in general exploration to intensified various sampling works of which the interval shall be sufficient to determine the deposit continuity. Laboratory tests for processing performance or enlarged continuity are involved. If necessary, pilot-scale test shall be carried out providing basis for the feasibility study or mine construction and engineering.
2.3 Geological assurance reflects different accuracy of the achievements at mineral exploration stages and can be divided into four categories: the measured, indicated, inferred and reconnaissance.
2.3.1 Reconnaissance: refers to the result obtained by reconnaissance of area with enhanced mineralization potential. Estimates of quantities should only be made if sufficient data are available and when an analogy with known deposits of similar geological character is possible.
2.3.2 Inferred: refers to finding out the geological characters of minerals, distribution features, grade and quality of ore body (ore point) in the prospecting area according to appropriate accuracy and still includes the basic reserves of enhanced geological assurance and extrapolation of resources. Because of limited information, multiple uncertainties, inferred continuity of ore body (point) and limited data bases for quantitative estimation, the level of confidence is low.
2.3.3 Indicated: refers to basically finding out the main geological characters of deposits, ore body shape, occurrence, scale, ore quality, grade and technical conditions of mining in a certain mining area according to the general exploration accuracy. As the continuity ore body is basically determined and the data bases for recourse quantity estimation are sufficient, the level of confidence is high.
2.3.4 Measured: refers to definitely finding out the geological characters of deposits, ore body shape, occurrence, scale, ore quality, grade and technical conditions of mining in mining area according to the detailed exploration accuracy. As the continuity ore body is basically determined and the detailed data bases for recourse quantity estimation are sufficient, the level of confidence is high.
2.4 The feasibility assessment can be divided into three stages: geological study, prefeasibility study and feasibility study.
2.4.1 Geological study: is an initial evaluation of the economic viability for deposit exploitation. the indexes adopted, e.g. ore grade, ore body thickness and burial depth, normally are empirical data accumulated over a few decades from domestic mining and the mining cost is estimated from comparable mining operations. The purpose of the geological study is to define an investment opportunity. Because of the lack of accurate parameters and detail necessary for an economic viability evaluation, the resource quantities estimated may be of intrinsic economic interest only.
2.4.2 Prefeasibility study: provides a preliminarily assessment of the economic viability of a deposit. The result may form the basis for justifying further detailed exploration or feasibility study on the deposit Such study normally shall involve the mineral resources/reserves quantities obtained from the industrial indexes after general exploration or detailed exploration, laboratory scale processing test data, cost estimated from the data acquired from price catalogue or comparable mining operations. The prefeasibility study addresses the items listed under the feasibility study (see Appendix C), although not in as much detail. In case of the prefeasibility study for selecting project proposal, the investor shall the indexes and parameters suitable for the market price to the date and the project demonstration shall be complete as much as possible.
2.4.3 Feasibility study: a feasibility study assesses in detail the economic viability of a deposit and the technical soundness of a proposed project and its result may serve as the basis for the investment decision. The cost data adopted are of high accuracy and normally are based on the reserve figures from detailed exploration and corresponding processing performance test results. The cost and parameters required by equipment quotations are based on the market price to the date. It takes full consideration of the influences of various factors, e.g. geology, engineering, environment, laws and governmental economic policies, and thus is of high timeliness. The items in feasibility study are given in Appendix C.
