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Hydrotermale mineralforekomster. Ca. Si. K. Li. Na. Ti. Al. Ta. B. O. Fe. P. Au. Li. Cu. Ta. Ti. B. Mo. Al. Si. Bi. Fe. Qz. Kfld. Au. Mo. Au. Li. Li. B. Cu. B. Cu. Ta. Mo. Ta. Cu. Au. Mo. Fluid inclusion trails in quartz. Glassy. Milky.
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Ca Si K Li Na Ti Al Ta B O Fe P
Au Li Cu Ta Ti B Mo Al Si Bi Fe Qz Kfld
Au Mo Au Li Li B Cu B Cu Ta Mo Ta
Cu Au Mo
Fluid inclusion trails in quartz Glassy Milky
Different types of fluid inclusions Trains of secondary inclusions along healed micro-fracture Primary inclusion with daughter mineral Primary inclusions with sylvite (KCl)
MINERALFOREKOMSTER DANNET VED HYDROTERMALE PROSESSER Viktige forekomster av metaller: Cu, Mo, Sn, W, Fe, Au, Ag, Zn, Pb Viktige forekomster av industrimineraler: Zeolitt, asbest, talk, kaolin, pyrofylitt, flusspat Endogene, hypogene, epigenetiske og (stratabundete) Avsetninger som fyller alle typer av sprekker, hulrom og rom etter utlutete mineraler
Skorpedyp: • Episonale forekomster: 0-5 km dyp, kaolin, Zn-Pb, • flusspat, Au-Ag • Mesosonale: 5-10 km, Au, Sn-W, Cu-Mo, talk, asbest • Hyposonale: 10-20 km, Au • Mineralene fyller: • Forskastninger/store sprekker, gangmineraliseringer • Nettverk av sprekker, stokkverk- el. porfyr mineral. • Tektoniske, kollaps og hydrauliske breksjer • Hulrom og porer i sandsteiner, karst-rom i karbonater • og fortrenger primære bergartsmineraler • (hydrotermal omvandling)
Drivkraft: Termiske gradienter og trykkgradienter Væsketyper: Metamorft vann (dehydrering av vann-holdige mineraler), magmatisk vann (salt-rikt vann avblandet fra granittiske smelter) og overflate vann/grunnvann. Gull-kvarts-turmalin gang
Volcanic hosted Cu, Zn, (Au)
Volcanic hosted Cu, Zn, (Au)
Volcanic hosted Cu, Zn, Pb (Au)
Sedimentary hosted Zn, Pb, Cu, Ag
Carbonate hosted (MVT) Pb – Zn - Ag
Champagne Pool, New Zealand 1-3 g/t Au Kaolinitt Kvartsårer med Ag +Au AgS
Ore deposits related to granitic plutons are formed by the interaction of two major processes: Exsolution of metalliferous magmatic water during crystallization of the pluton. Heat source for the convection of meteoric and/or metamorphic water which may leach metals from the rocks along their pathways.
Ores consisting of a stockwork of thin polygeneration veinlets of quartz, ore-sulphides and pyrite. Sulphides also as dissemination, i.e. along micro-fractures
Stockwork of quartz-sulphide veins enveloped by quartz-pyrite-sericite alteration (phyllic; brown) in granodiorite
HYDROTERMAL OMVANDLING Sprekkebundet talk omvandling Serpentinitt (venstre) and peridotite (høyre)
Caledonianmantle fragmentsAlteration Talc Talc LinnajavriVery largetalc resource Altermark Mine in operation by Norwegian Talc (Omya) Raudfjellet Large talc and magnesite resource
O Bauxite Saprolite gold A1 Nickel laterite Al Au A2 Ni C D RESIDUAL FOREKOMSTER METAL ACCUMULATION DURING WEATHERING
Garnierite, Ni-serpentine (Ni, Mg)3Si2O5(OH)4 Ni laterite deposits NEW CALEDONIA
Sekundær anrikning • Overflatevann • Utluting fra øvre del av en forekomst • Utfelling lengre ned • Gull • Sølv • Residuale forekomster • Utluting av løselige mineral fører til en oppkonsentrering av de ikke-løselige • Garnieritt (vannholdig silikat av nikkel og magnesium) • Lateritt (jern og/eller aluminium) • Bauxitt (lateritt med nesten bare aluminium)
Sedimentære mineralforkomster Precambrian Banded Iron Formations, Australia (BIF, viktigste kilde til jern)
Entrapment mechanisms for gold and other heavy minerals in fluvial systems Physical barriers
Gold accumulation Old river bed Meandring stream Heavy-mineral sand Zone of suiteable velocity of flood water
Witwatersrand alluvial fans Ventersdorpbasalt VCR conglomerate
Beach-placers formed by heavy-mineral separation by action of waves, wind and current Normal situation Open stormy coast Storm waves Windy
Reserver Kendte ressurser der kan utnyttes idag innen givne økonomiske og juridiske rammer Kennecott Open Pit Copper Mine, Utah
Destructive plate margin Contructive plate margin Destructive boundary Contructiveboundary Marginal basin Spreading ridge International terminology for the different platetectonic elements Ensialic island arc Continental island arc Subduction trench Ensimatic island arc Back-arc basin Foreland basin Continent Oceanic crust (ophiolite) Continental crust Fore-arc prism Benioff zone (zone of earthquakes)
DV DV Intracratonic CV DV Intracontinental CV CV CV CV TF CV DV CV TF TF CV TF DV DV CV CV DV DV TF DV DV DV DV = divergent plate margin CV = convergent plate margin TF = transform fault Present plate configurations Continental drift