Khoa hoc cong nghe
NHUTNG K Y T H U A T T H A M DO MGfl
Cac khoang san chi thj dong porphyry
T rong 20 nim qua, cie nha dja chat da nghiin culi ip dgng cie "khoing sin ehi thi" Ii mdt cdng cg Hem kiem. Cac "khoing sin chi thj" la nhutig khoing sin mi hiin diin eiia chiing cung cap cho cie dau mdi dan tdi xic dinh dUde vj tri ciia mdt md, cd eac khoing sin ed gii trj nhU: ving, ddng, kim eUdng. Viec thim dd va sd dgng eic "khoing sin ehi thj" dau tien dUde thyc hiin thanh cdng trong tim vang va kim eUPng. Mdi diy, vlic sU dung cie "khoing sin chi thj" trong thim dd da
dugc md rdng v i hiin dugc sii dgng trong tham dd cac
khoing sin nhU: tungsten, uranium va ddng...
Oe thu hep cdng tie tim kiim mdt md khoing sin cd gii trj kinh te, cie nha dja chat da day manh tien hanh thf nghiim cie thudc tinh hda va vat ly ciia khoing sin chi thj.
Kit qui phan tich hda chat ciia mdt "khoang sin ehi thj" cd the eung cap thdng tin cho nhi thim dd hoic khdng cd mdt khoing sin nio dUdc tim thay trong ciing dieu kiin nhU
"khoing sin chi thj" dUde xic dinh muc tiiu tim kiem. Kit qua thi nghiim vat ly eiia mdt "khoang sin ehi thj" giup cie nhi dja chat di sau vao khoang sin mge tiiu. Vf dg nhU, nhChig tfnh chat vat ly ciia mdt khoang sin da bi xdi mdn ty da gde va bj djch chuyen den mdt dia diem mdi, ed the cho
kha nang nghiin culi vj trf 6a gde ciia mdt md khoang san.
Nghiin euli mdi day tap trung vio viic ip dgng ciia cac
"khoang sin ehi thj" porphyry (PIM), de xic djnh vj tii ciia cac md dong porphyry "an nau" dUdi nhCitig khdi IUdng bang tfch Idn. PIM la nhChig khoang sin hinh thanh trong qua trinh hinh thanh mdt md dong porphyry. Khoing san sir dgng trong nghiin culi PIM la nhutig khoing sin khang, hoic Ii nhdng khoang sin khing lai xdi mdn. Khi nhOtig khoing sin khang niy dUdc tim thay, nd eung cap dau mdi xae djnh vj tri ciia mdt md d i gde ddng porphyry gan do.
Thdng thudng sd dung PIM bao gdm apatite, rutile, garnet va titanlte. NhCitig khoing sin nay, khi hinh thanh hoae bien ddi trong mdi trUdng thuy nhlit, ed nhCitig thudc ti'nh doc dio nhu miu sic, kfch ed v i hinh ding. NhCitig thupe tinh nay eho thay sy hiin diin eua chiing dUde sy dung la mpt cdng eg tim kiim. Thim nda, thinh phan hoi chat ciia PIM cd the xae djnh eic mdi trUdng khoing hoi, mdi trUdng nay Hin quan trye tiip din nhCitig vung thay dfii riing blit trong cac h i thdng porphyry. Cie nhi dja chat dinh gia sy hlfn diin, thinh phan, sd IUdng va ty I i eua PIM dUde tim ttiay trong vat lieu be mit nhU bing tieh, vdi mge tiiu dang che giau nhutig md ddng porphyry.
58|KHOA HOC & CONG NGHE • (Sd) 7 - 9/2011)
Nghiin euli khoing sin PIM hiin dang dugc i p dgng d eac khu vyc tinh British Columbia ciia Canada. Tai diy, cie nhi dja chat dUa ra ly thuyet mdt md dong ed g i i trj dUde bao phii bdi mdt IUdng Idn bing tich. Xuat hiin thdng thudng ciia eic khoang sin khing I i nhutig sin pham thay ddi trong cie md ddng porphyry d British Colum- bia cho thay, nhCfng "khoing sin ehi thj" porphyry nay (PIM) cd the dem d i n mdt cdng cg quan trpng de dan tdi thanh cdng mge tiiu thim do.
Viic sd dgng PIM la mpt bUde t l i n quan trpng trong sy dgng "khoing san ehi thj" cho tham dd ddng, bdi khoing sin sulfide di ciing eic md ddng khdng cd sde khing mdn nhieu. Bang cich sy dgng cie khoang sin khing I i nhiitig "khoang sin ehi thj", ngUdi lam cdng t i e thim dd cd the thu hep diin tfch tim kiim mdt md ddng, tham chf niu c i khi nhCitig khoing sin sulfide da bj phong hda.
PIM dugc sii dgng thanh cdng trong xic djnh cie md ddng porphyry d Otxtriylla v i dang dupe md rdng nghien euli d Bac My. Nam 2007, Cgc Oja chat My (USGS) b i t dau dy i n nghiin eyu hpp tic vdi Cdng ty Northern Dynasty Minerals (hiin nay la Cdng ty Pebble Limited Partnership, PLP) de tiin hanh cie nghiin ciTu 6 md Pebble por- phyry Cu-Au-Mo tai mien Tay Bac Alaska. Md Cre- taceous Pebble dUde ehe phii dUdI lanh nguyen, bang tieh va d i phii ky de tam. Cie nghien culi ciia USGS I i mdt phan eiia mdt dy i n qude gia nham dinh g i i v i phit hiin nhdng tai nguyen cdn bj che giau. PIM cung dUdc i p dgng d cac dja khu Quesnel va Stiklne trong trung phan British Columbia. Cie dja khu niy ed tiem ning Idn ve cac md ddng porphyry. Tuy nhien, k i t qua thim dd trong viing niy bj ban che bdi dp mdng cua thin quing, nhutig Idp phii bang k i t rdng Idn v i cie tram tieh lin bing g i i phii tren mdt viing q u i rdng. Mac dii cie md ddng Idn tren the gidi se dupe phat hiin, Cdng ty Highland Valley Copper Mine dang tiep tuc cdng tac tham dd trong khu vUc, it quan t i m bdi sd IUdng qua Idn bang tfch phii trin da gde trong khu vyc. Cie dy an nghiin cull PIM d British Columbia dem lai mdt IUdng Idn cie thdng sd dja hoi v i dja vat ly mdi, cac thdng sd nay rat quan trpng, d i m bio cho nhdng cd ging thim dd tiip theo. Oe ning cao sy bleu biet mdi quan h i giu^ PIM va cie ddng cd tinh kinh te, cie nhi dja chat tiin hinh phin tfch de xic djnh cie tiiudc tfnh vat ly ciia cie khoing sin ehi thj nhu dp phong phu tUdng ddi ciia cie chiing loai khoing sin, hinh dang hat khoing va kich ed hat.
Cie khoing san khing ed the lap day khoing tidng fating kiin thde tiiim dd hiin nay v i cd tiem ning dem lai Hin k i t dang mat di gvjta md quing va Idp phu tram tich bing h o i . *
TRAN MINH HUAN Copper Investing News
Khoa hoc cong nghe
Khai thac than
a incfonexia
L
a mdt dat nude t d liu ndi tiing ve giau t i i nguyen, Inddnexia da khai thie than qui md Idn td mdt thap ky qua.Hiin nay, dat nUde nay la nUde xuat khau than nhiet trj cho sin xuat diin Idn nhat t h i gidi, xuat khau hdn 265 trieu tan trong nim 2010. Vdi than ham IUpng thap va chi phi van tai va nhan cdng cung thap, Inddnixia da trd thanh mdt dia chi cd tieng ddi vdi cac thj trUdng mdi troi day nhU: Trung Qude va An Op, trong khi do, nUde nay cung ddng vai trd cung cap than chii yeu cho Nhat Ban, Han Qude va Oil Loan.
Inddnixia da khai thie 325 trieu tan than nhiet trj trong nam 2010, tang 14,8% so vdi nam 2009. Nam 2011, nUde nay dUa ra mge tieu khai thie than nhiet trj dat t d 335 - 350 triiu tan. Tong tai nguyin vUdt 4,3 ty tan, khien qude gia nay dutig hang thd 4 the gidi, nhutig thiiu cd sd truyen tai dien va thiet bi sin xuat, nin 72% sin IUpng than nhiet trj phai xuat khau.
OUdc trdi phii cho nhieu than nhiet trj, qude gia nay xuat khau than chat IUdng thap hdn so vdi than d cie md khae trin the gidi nhu Otxtriylia. Tuy nhiin, 66% trd IUpng than qude gia cd nhiet trj rieng khoing 5.100 - 6.100 keal/kg, 20% ti-d IUdng than ed nhiet trj rieng dUdi 5.100 va 14% tU 6.100 den 7.100 keal/kg.
Trong 3 nam qua, d i u tU nUde ngoai do vao nUde niy, phan Idn la t d Trung Qude v i An Op I i nhutig nen kinh t i dang banh trUdng tim ngudn than cho sin xuat dien d cie qude gia n i y Tuy nhiin, cie cdng ty qude te tiip tgc than van vi nhiitig bat cap ciia Luat Khai thie than va khoing sin cua nUde niy dUa vao i p dgng ty2009.
LUAT KHAI THAC M d i
Nam 1998, sy bat dn kinh t i v i chinh trj b i t budc Tong thdng Suharto sau 32 nam cam quyen phii cai cich chinh trj. Td nhutig
Moong khai thie than dia Cdng ty BUMI
(S6 7 - 9/2011) < KHOA HOC & CONG NGHE: 59
