Mitundu ya Mineral Deposits
Miyala ya mchere yakhala maziko a chitukuko cha mafakitale ndi kupita patsogolo kwa ukadaulo m'mbiri yonse ya anthu. Kuyambira chuma chamtengo wapatali cha golide cha zitukuko zakale mpaka silicon yomwe ilipo paliponse mu zamagetsi amakono, mchere wasintha njira ya zochita za anthu. Kumvetsetsa mitundu ya miyala yamchere ndikofunikira kwambiri kuti ichotsedwe bwino komanso mosalekeza. Nkhaniyi ikufotokoza mitundu yosiyanasiyana ya miyala yamchere, pofufuza kapangidwe kake, makhalidwe ake, ndi kufunika kwake.
1. Madipoziti a Magmatic
Ma depositi a magmatic amapangidwa mwachindunji kuchokera ku ma crystallization ya magma. Pamene magma ikuzizira ndikulimba, mchere umasungunuka ndikuwunjikana m'magawo kapena madera osiyanasiyana. Ma depositi awa amapereka mchere wofunika kwambiri. Mitundu yayikulu ya ma depositi a magmatic ndi awa:
a. Kulowerera Kokhala ndi Zigawo
Kulowa m'malo ozungulira ndi matupi akuluakulu, ofanana ndi mapepala a miyala ya igneous yomwe imapangidwa kudzera mu kuzizira pang'onopang'ono ndi kupanga magma mkati mwa nthaka ya Dziko Lapansi. Chromite, magnetite, ndi platinum group metals (PGMs) makamaka zimachotsedwa m'malo awa. Bushveld Igneous Complex ku South Africa ndi chitsanzo chabwino.
b. Ma Pegmatite
Ma Pegmatite ndi miyala ya igneous yokhala ndi tinthu tating'onoting'ono kwambiri yomwe imapangidwa kumapeto kwa magma crystallization. Amadziwika kuti ali ndi makhiristo akuluakulu komanso osowa a mchere monga spodumene (gwero la lithiamu), beryllium (beryllium), ndi tourmaline.
2. Malo Osungiramo Zinthu Zotentha ndi Madzi
Ma hydrothermal deposits amachokera ku madzi otentha komanso okhala ndi mchere wambiri omwe amasuntha kudutsa mu nthaka ya Dziko Lapansi. Ma deposits awa ndi ena mwa magwero ofunikira kwambiri a zitsulo. Amagawidwa m'magulu kutengera malo omwe amapangika komanso mawonekedwe a madzi.
a. Mitsempha Yosungidwa
Mitsempha ya m'mitsempha imachitika pamene madzi olemera a hydrothermal amadzaza ming'alu ndi kusweka kwa miyala yomwe inalipo kale. Mitsempha imeneyi imatha kukhala ndi zitsulo zamtengo wapatali monga golide ndi siliva, komanso mkuwa, lead, ndi zinc.
b. Ma Deposits a Porphyry
Ma porphyry amapezeka m'minda ikuluikulu, yotsika mtengo kuchokera ku madzi otentha ochokera ku hydrothermal omwe amabwera chifukwa cha ntchito ya volcano. Ndi gwero lalikulu la mkuwa, molybdenum, ndi golide. Ma porphyry amafalikira m'miyala yonse, zomwe zimapangitsa kuti migodi yotseguka ikhale njira yothandiza yochotsera zinthu. Mgodi wa Bingham Canyon ku Utah ndi chitsanzo chabwino.
c. Ma Epithermal Deposits
Madontho a epithermal amapangika pafupi ndi dziko lapansi, mkati mwa makilomita ochepa kuchokera ku crust, kuchokera ku madzi omwe amatuluka m'minda ya geothermal. Ndi magwero ofunikira a golide ndi siliva ndipo nthawi zambiri amagwirizanitsidwa ndi malo ophulika mapiri.
3. Malo Osungira Madzi Otayidwa
Ma sedimentary deposits amapangidwa kuchokera ku kusonkhanitsa ndi kugawa kwa tinthu ta mchere m'malo osungiramo zinthu. Ma sedimentary deposits amenewa ndi a stratiform, zomwe zikutanthauza kuti amapezeka m'miyala ya sedimentary yokhala ndi zigawo.
a. Madipoziti a Placer
Malo osungiramo zinthu (placer deposits) amapezeka kuchokera ku kuchuluka kwa mchere wolemera womwe umayikidwa m'madzi oyenda. Golide, diamondi, ilmenite, ndi rutile zimapezeka kwambiri m'malo osungiramo zinthu awa. Malo osungiramo zinthu zakale a golide pa nthawi ya California Gold Rush ndi malo osungiramo zinthu za diamondi ku Namibia ndi zitsanzo zakale.
b. Mapangidwe a Chitsulo Cholumikizidwa (BIFs)
Ma BIF ndi magwero ofunikira a chitsulo. Amapangidwa ndi zigawo zosiyanasiyana za mchere wolemera mu chitsulo ndi silika. Miyala yakale iyi ya sedimentary, yomwe idapangidwa zaka zoposa 2.5 biliyoni zapitazo, ikuwonetsa kusintha kwakukulu mumlengalenga ndi chilengedwe cha Dziko Lapansi. Zitsanzo zodziwika bwino zikuphatikizapo Hamersley Range ku Australia.
c. Ma Deposits a Evaporite
Madontho a nthunzi amapangidwa kudzera mu nthunzi ya madzi amchere m'mabotolo otsekedwa. Halite (mchere wa miyala), gypsum, ndi potashi ndi mchere wofunikira wochokera ku nthunzi. Malo akuluakulu amchere ku Bonneville ku Utah amasonyeza madontho otere.
d. Mafosholo a Phosphorite
Ma phosphorite ndi magwero ofunikira padziko lonse lapansi a phosphorous, michere yofunika kwambiri pakukula kwa zomera. Miyala ya sedimentary iyi ili ndi mchere wambiri wa phosphate, womwe nthawi zambiri umapezeka m'madzi a m'nyanja. Ma depositi ambiri ku Morocco ndi ena mwa akuluakulu padziko lonse lapansi.
4. Ma Deposits Osinthika
Ma metamorphic deposits amachokera ku kusintha kwa miyala yomwe inalipo kale pansi pa mikhalidwe ya kuthamanga kwambiri ndi kutentha. Njirayi ingayambitse kugawikana kwa mchere wamtengo wapatali m'malo osakanikirana.
a. Skarns
Ma Skarn amapangika pomwe ma igneous intrusions amakumana ndi miyala ya carbonate, zomwe zimapangitsa kuti pakhale kusintha kwakukulu kwa calcium-silicate minerals. Ndi magwero ofunikira a tungsten, copper, gold, ndi garnet.
b. Malo Osungiramo Zinthu Zobisika za Greenschist ndi Amphibolite
Ma depositi amenewa amapangidwa pansi pa madigiri osiyanasiyana a kupanikizika ndi kutentha panthawi ya kusintha kwa chilengedwe. Miyala yamtengo wapatali monga talc, graphite, ndi kyanite nthawi zambiri imagwirizanitsidwa ndi zinthu izi za metamorphic. Variscan Belt ku Europe ili ndi zitsanzo zambiri.
5. Madipoziti Otsala
Ma depositi otsala amapangidwa chifukwa cha kuwonongeka kwa mankhwala m'miyala, zomwe zimapangitsa kuti mchere usasungunuke.
a. Laterites
Ma depositi a Lateritic amapezeka m'madera otentha komanso otentha omwe mvula imagwa kwambiri. Ali ndi chitsulo chochuluka ndi ma oxide a aluminiyamu. Bauxite, yomwe ndi chitsulo chachikulu cha aluminiyamu, imachokera makamaka ku ma depositi a lateritic. Ma depositi odziwika bwino a bauxite amapezeka ku Australia, Guinea, ndi Brazil.
b. Nickel Laterites
Miyala ya nickel laterite imachitika chifukwa cha kuwonongeka kwamphamvu kwa miyala ya ultramafic, zomwe zimapangitsa kuti pakhale dothi lolemera ndi nickel. Miyala imeneyi ndi yofunika kwambiri pochotsa nickel ndipo imapezeka m'maiko monga Indonesia, Philippines, ndi New Caledonia.
6. Ma Deposits a Volcanogenic Massive Sulfide (VMS)
Ma VMS deposits ali ndi mchere wochuluka wa sulfide, womwe umapezeka pansi pa nyanja kapena pafupi ndi nyanja chifukwa cha kutentha kwa madzi komwe kumachitika chifukwa cha mapiri. Ndi magwero ofunikira a mkuwa, zinc, lead, golide, ndi siliva. Mgodi wa Kidd Creek ku Canada ndi umodzi mwa migodi yayikulu kwambiri ya VMS padziko lonse lapansi.
Kutsiliza
Kumvetsetsa mitundu yosiyanasiyana ya miyala yamtengo wapatali ndi njira zake zapadera zopangira zinthu n'kofunika kwambiri kuti chuma chizipezeka bwino komanso mokhazikika. Mtundu uliwonse wa miyala yamtengo wapatali umapereka chidziwitso cha mbiri ya dziko lapansi komanso umapereka zinthu zofunika kwambiri zomwe zimathandizira anthu amakono. Njira zoyendetsera migodi mokhazikika komanso njira zamakono zofufuzira zidzaonetsetsa kuti miyala yamtengo wapataliyi ikupitilizabe kuthandiza anthu kupita patsogolo kwa mibadwo ikubwerayi.
