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Ore deposits formed by lateral secretion are formed by metamorphic reactions during shearing, which liberate mineral constituents such as quartz, sulfides, gold, carbonates, and oxides from deforming rocks, and focus these constituents into zones of reduced pressure or dilation such as faults. This may occur without much hydrothermal fluid flow ...
Economic geology is concerned with earth materials that can be used for economic and industrial purposes. These materials include precious and base metals, nonmetallic minerals and construction-grade stone. Economic geology is a subdiscipline of the geosciences; according to Lindgren (1933) it is “the application of geology”.
The economic viability of a deposit will also depend on the grade and tonnage of the reserves of a deposit, along with the costs associated with extracting the ore. Methods of delineating reserves and of extracting gold ore are improving over time, increasing the possibility for production of more gold. [47]
Resources change over time with technology and economics; more efficient recovery leads to a drop in the ore grade needed. The average grade of the copper ore processed has dropped from 4.0% copper in 1900 to 1.63% in 1920, 1.20% in 1940, 0.73% in 1960, 0.47% in 1980, and 0.44% in 2000. [8]
An overview of one of the regolith-hosted rare earth element deposits (a type of Rare Earth Element mine) in South China [1]. Regolith-hosted rare earth element deposits (also known as ion-adsorption deposits) are rare-earth element (REE) ores in decomposed rocks that are formed by intense weathering of REE-rich parental rocks (e.g. granite, tuff etc.) in subtropical areas. [2]
Soil layers, from soil down to bedrock: A represents soil; B represents laterite, a regolith; C represents saprolite, a less-weathered regolith; below C is bedrock Tropical weathering (laterization) is a prolonged process of chemical weathering which produces a wide variety in the thickness, grade, chemistry and ore mineralogy of the resulting ...
Agricultural economics is an applied field of economics concerned with the application of economic theory in optimizing the production and distribution of food and fiber products. Agricultural economics began as a branch of economics that specifically dealt with land usage. It focused on maximizing the crop yield while maintaining a good soil ...
The Essay has been described as different from earlier writings on economic methodology in generating a range of tightly argued, radical implications from a simple definition, for example in admitting an aspect of behaviour (rather than a list of behaviours) but not limiting the subject-matter of economics, provided that the influence of ...