tài nguyên khoáng sản

35 760 0
tài nguyên khoáng sản

Đang tải... (xem toàn văn)

Tài liệu hạn chế xem trước, để xem đầy đủ mời bạn chọn Tải xuống

Thông tin tài liệu

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

Ngày đăng: 04/05/2014, 23:23

Mục lục

  • Common Use of Mineral Products

  • Mineral Resources and Reserves

  • Responses to Limited Availability

  • Geology of Mineral Resources

  • Genesis of Mineral Resources

  • Some Important Minerals and there Uses

  • Plate Tectonics and Mineral Resources

  • Geochemically Abundant Elements (GAE)

  • Geochemically Scarce Elements (GSE)

  • Comparison of Concentrations of Elements in the Earth’s Crust with Concentrations needed to operate a Commercial Mine

  • Process that concentrate elements

  • Ways to overcome the mineralogical barrier

  • Plate Tectonics and Resources

Tài liệu cùng người dùng

  • Đang cập nhật ...

Tài liệu liên quan