mineral resources Flashcards
(39 cards)
what is a mineral?
-naturally occurring inorganic solid, with a definite chemical composition
-not made by humans
-never been alive, not made up from plants/animals
-each one made up of particular mix of chemicals
what is the use of mineral resources?
-non-renewable
-they reformed too slowly to be replaced with timescales that would allow human use
-long-term use relies on understanding of scientific methods that will increase supplies, extend use, find alternatives for those in restricted supplies
what is the lithosphere?
-outermost shell of a terrestrial planet or natural satellite. on earth, its composed of the crust and portion of the upper mantle
-includes rocks, solid, mineral resources that are impact for human society
what does hydrothermal mean?
-action of heated water in the earths crust
what does deposition mean?
-laying down of sediment carried by wind, flowing water, the sea or ice
what does alluvial processes mean?
-involves materials being carried and separated by flowing water
what are the types of rock?
-igneous= has crystals
-sedimentary= has grains bound together by a cement
-metamorphic= has crystals
what are igneous rocks?
-if the magma cools slowly underground, theres more time to cool so crystals grow large
-these rocks are called intrusive rocks
-if the magma cools quickly on surface of earths crust theres no time fro crystals to grow so theyre very small
-these rocks are called extrusive rocks
what is hydrothermal deposition?
-igneous intrusions= magma pushes up, cools & solidifies within crust forming batholith
-intrusions produce pressurised superheated water
-dissolves minerals in surrounding rock
-mineral rich solutions travel along fissures away from batholith & cool
-minerals come out of solutions in order of solubility
what is fractional crystalisation?
-as superheated water cools along hydrothermal vents minerals come out of solution
-least soluble crystalise first and deposited in layers in vents
-later explored and extracted
-allows access to minerals that otherwise couldnt be extracted
-minerals include tin, copper, lead, silver, gold, and arsenic
what are sedimentary rocks?
-form from compaction of pre-existing pieces of rock and mineral
-a previous rock must be weathered and eroded, and particles transported and then deposited
-then the grains are compacted, and the pressure binds the loose sediment together to form a rock
what are metamorphic rocks?
-common economically used rocks are slate and marble
-slate was once mudstone or clay that’s been altered by intense heat/pressure
-marble was once limestone which was heated and recrystalised
what are proterozoic marine sediments?
-includes iron ores deposits
-formed when dissolved iron compounds become oxidised by oxygen released from photosynthesis
-produces insoluble iron oxide deposits
-occurred mainly between 2.5 and 2.8 billion years ago
what are biological sediments?
-when mineral deposits form from biological organisms
-this often concentrates the mineral that are then deposited in sedimentary rocks
what are alluvial deposits?
-refer to the movement and separation of materials caused by flowing water
-the velocity of the water dictates the ability of the water to carry solids,and the density of solids that can be transported. humans exploit alluvial deposits including:
*gold
*gravel
*sand
*clay
*diamond
what is stock?
all resources that can be exploited now, in the future, or never
what is a resource?
all materials that are theoretically available, including material that is currently economically unavailable to extract or cannot be extracted either current technology
what is a reserve?
portion of the resource that can be exploited now, economically using existing technology
what are reserves and resources?
-quantity of every metal present in the lithosphere far exceeds realistic human demands
-only a portion of it will ever be exploitable and even less can be exploited economically
what is laskys principle?
as purity of a mineral decreases, the mass of montreal’s present increases exponentially
what is cut off ore grade?
-minimum grade required for a mineral or metal to be economically mined
-material found to be above this grade is ore, material below is waste
-measured in grams per tonne (g/T)
what is inferred reserves?
-presence of mineral has been predicted by knowledge of geological structures but isn’t completely accurate, & not enough to estimate the quantity that can be extracted
what are potable reserves?
sufficient info is available on the minerals so that the quantity can be estimated, proves that further exploration is justified
what are proven reserves?
sufficient exploration has been carried out to get an accurate estimate so the mineral can be extracted
