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Mineral Resources Mineral Resources • Backbone of modern societies • Availability of mineral resources as a measure of the wealth of a society • Important in people’s daily life as well as in overall economy • Processed materials from minerals account for 5% of the U.S GDP • Mineral resources are nonrenewable Mineral Value • Direct value – Raw, recycles – Import, export • Indirect value – Processes • Value added – E.g., agriculture Common Use of Mineral Products METALLIC HYDROCARBON NON-METALLIC Mineral Resources and Reserves • Mineral resources: Usable economic commodity extracted from naturally formed material (elements, compounds, minerals, or rocks) • Reserve: Portion of a resource that is identified and currently available to be extracted legally and profitably • Defining factors: Geologic, technological, economic, and legal factors Reserves vs Resources • Reserves – Natural resources that have been discovered & can be exploited profitably with existing technology – Oil – 700 billion barrels • Resources – Deposits that we know or believe to exist, but that are not exploitable today because of technological, economical, or political reasons – Oil – trillion barrels Mineral Resources Problems • Nonrenewable resources – Finite amount of mineral resources and growing demands for the resources • Supply shortage due to global industrialization – More developed countries consuming disproportionate share of mineral resources • Erratic distribution of the resources and uneven consumption of the resources – Highly developed countries use most of the resources; supply varies Major Import Sources (Table 14.2) • Friends – Canada: Metals – United Kingdom: platinum, rare earths • Other – China: graphite, tin, tungsten… – South Africa : platinum, fluorspar – Chile: arsenic, iodine Responses to Limited Availability • • • • Find more sources Find a substitute Recycle Use less and make more efficient use of what is available • Do without Process that concentrate elements • Igneous Processes – Hydrothermal – Magmatic • Sedimentary Processes – Mechanical – Chemical • Metamorphism Processes • Groundwater Processes Hydrothermal Processes • Precipitation of metallic ions from hot, ion-rich fluid • Fluid could be – Magmatic – Groundwater – Oceanic water • Magmas heat up the water • Water flows into fractures, faults, joints, etc where it cools and precipitates (deposits) the metals Magmatic Processes • Gravity Settling – Dense, early-crystallizing minerals sink to the bottom of the magma chamber • Filter Pressing – Tectonic force compress a magma chamber and force the still-liquid portion into fractures, creating large crystals • These processes have produced large bodies of iron, chromium, titanium, and nickel Sedimentary Processes • Clastic – Weathering of rock also weathers out elements of interest – Generally, the elements are heavy and are deposited when a streams competence is low – Placer deposits, Placer Gold Sedimentary Processes • Chemical Precipitates – Water with high concentrations of elements is evaporated – Evaporation of water leaves the elements – Ex Salts, Iron, etc Metamorphism • Alteration of rock concentrates the elements • The heat and pressure force out the GSE (“impurities”) Weathering • Chemical weathering removes soluble material • Ore material (elements of interest) are left behind in a concentrated residue Groundwater • Secondary enrichment • Groundwater dissolves and carries elements in solution • Chemical conditions change and the elements are precipitated (deposited) out • Ex Lead Groundwater • Secondary enrichment • Groundwater dissolves and carries insignificant elements in solution • Insoluble elements of interest remain • Ex Aluminum Ore Mineral • Ability to separate and readily process the metal (element) from the ore material • Need to look at – The energy to process the material – The cost to process the material – The value of the metal • Basically, is it profitable to mine the metal? Mineralogical Barrier • Increase in energy and cost associated with the production of GSE Metals trapped in minerals (silicates) Energy and Cost per mass of metal Mineralogical Barrier GAE $ GSE Metals the have been concentrated Fixed Costs Low Grade of metal (element) in rock High Ways to overcome the mineralogical barrier • Improve technology • Recycle • Come up with cheap energy to break silicate bonds Daily Assignment 2, 3, Place the following on the Venn Diagram 1.Gold 2.Oil 3.Coal 4.Iron 5.Copper 6.Gravel Plate Tectonics and Resources