TapdilDIACHAT-kiatA. 50319, 7-&<2010 n
B^C DIEM PHAN B 6 DA HOA TRANG 6 PHIA TAY TDVH
NGHE AN: DINH HlTOfNG THAM DO, KHAI THAC VA StJ'DUNG
NGUYEN TifeN THANH
Li&t^oan Dia djdl BSc Tnmg Bg, TPVirA,Ng^An
Tdm tat: Ng^ An cd tiim nang dd hoa tr&tg khd Idn, phmbd diu yiu d vimg pfrn 1^ cua tinh thugc dja bdn cdc hiyenQi^ Hop. Qt^ Chdu, Tdn KyvdN^iid Ban, vdi tmgta nguyen hon 900 aieulSi, gom 3 logt dd hoa lr^caicitfCaO>52%, A/^0
^.5%. Wb290H);d3hoatrdngdolomil(CaO:^3%,A^^5%. Wb >75-85%); dd hoa trdng calcit-dohmit (CaO ^2-50%. M^ Si-15%, Wb ^0-95%).
Cdc thdn dd hoa Ir^gphm bd apfda nam vdm ndng Bit Khgng dugc thmh tgo Irong qud trinh hoa hod da voi he tdng Bdc Son dudi tdc dgng hocU hod eda phuc nip ldi Bit Khgng vd tm ^g nhi4t cm cdc khdi xdm nhgp thugc cdc phuc hi Bdn Chieng Ye Yen Sun vdSdngMd.
Hi^n ngy. ddhoa trdng d Ngh4 An dang dugc thdm dd, khai Ihdc tren 65 vj iri khdc nhau vai tdng son lugng >U triiu tdn nam, nhung diin tich khai Ihdc manh mun, guy mo nhd. de gdy long phi khoang sdn va anh hudng din mdi trudng. Do vdy, cdn tien hdnh khao sdt ddnh gid Igi tdng Ihi tiim ndng ch& lugng dd hoa tr&igdi quy hogch chi liet c^g Idc thdm dd, khai thdc, che bien vd su dyng cd hi^u qudtng khodng sdn.
dja cMt k h o ^ san ty Id 1:50.000 v^ c ^ tai lieu khao sal g4n day cho thay trong vCing bao quanh v6m nang Bii Khang co nhiiu than da hoa ti5ng co quy mo khd 16n vk chit luqmg tdt, c6 dig su dung trong nhiiu ng^nh cong n ^ ? p khdc nhau.
IL DAC E)|£M PHAN BdOA HOATRANGd NGH$AN
1. Phan k>^ than dd hoa trSng 6 Ngh$ An Trong viing Quy Hop - Quy Chau - Tan K^ - Con Cuong is NghS An da khoanh dinh dugc hon 130 than da hoa trdng, phan bd chu yiu a vung Quy Hgp (110 thdn) va vung Tan Ky (20 than). Cdc than dd hoa tiing co cau tao detng via, thau kinh ldn, nam xen kep voi cac ldp m6ng da hoa mdu xam; chiiu ddy d^t 5- 25 m, CO ncfi tir 50 din hon 100 m; g6c cdm thoai: lO-SS**.
Theo thanh phdn thach hpc vd lmh v^c su dung, cdc thdn dd hoa trdng dugc chia thdnh 3 loai:
LMI^DAU
Dd hoa trdng Id mpt dang san phSm ddc bi?t ciia da v6i kit tinh trong qud trinh biin chdt, dugc su d\mg ldm da 6p Idt, dd my nghfi, dieu khdc va phu gia trong san xudt son, giay, chdt deo vd nhiiu nganh c5ng nghiep khdc.
Vung cdc huydn Qu^' Hgp - Quy Chau - Tdn K.^ - Con Cuong ndm bao quanh vdm nang Bii Khang. Ti> trung tdm vom ra ngoai ria lg ra dd phiin ket tinh thupc phirc h? Bii K h ^ g (MP-NP, bk\ da biin chit he tdng Su6i Mai (Np3-e2 sm\ tidm tich I\ic nguyen phan nhip hS tdng Sdng Ca (O2-S2 sc), tram tich luc nguyfin - carbonat chiia vJit chat than b? tdng La Khfi (CI Ik) va trfin cilng la dd vdi he tdng BSc Son (C-P2 6s). O tnmg tdm vom nang, cdc da xdm nh§p phiic he Bdn Chiing (Gsy,GDi/E 6c), phiic h? Ye Yfin Sun (G/K-E ys) xuyen cdt vd gdy bien chdi dd vdi Bdc Scm. Kit qud do ve bdn dd
_ / . / . ^11 Alia tring calcit: Qh co mau tiing, ti-ang ttong, ttjng phot xanh, dfl tting (Wb) dat 92-97%; da tao khdi, hat ttung bmh den Ion. Thanh phin khoang vSt cua da (%); calcit = 97-100; dolomit = 0,0-1; ham lugng ttimg btoh (%): CaO = 55,2-55,86; MgO = 0,12 - 0,29; Si02 = 0,01-0,38; AI2O3 = 0,01-0,03; FejOj =
<0,01-0,038. Ty tiBng ttung binh: 2,72;
flie ttpng tiung binh: 2,7 g/cm^ dp Im ttung binh: 0,23%; do hut nunc: 0,97%;
eu6n| do chiu keo ttung bmh: 47,55 g/cm , cudng do khang nen tiimg binh- 544,3 kg/cm'
Dd hoa ttjng calcit fliuong tjo flitah cdc fliSn khodng co chiSu day Ion >20m, k& dai hang ttSm din hang nghm met.' Dd hoa tting calcit loji co do nguyen kh6i t6t CO fli6 sii dung ldm dd 6p Idt, dieu khac, dd my nghe; con lai c6 fli6 nghijn thinh bOt sieu mjn de su dimg eho nhiSu lmh vuc cong nghifp khdc nhau.
1.2. Bi hoa tring dolomit: Da c6 mdu tiSng dye, tiing xdm, do tting: 75-85%
cdu tao khai hodc phdn lop ddy, hat min' Thdnh phan khodng vdt {%): dolomit'=
50-70; calcit = 30-50; fli,ch anh vd khodng v^t qujng rdt it gdp. Hdm lupng (%): MgO = >15%, CaO = 32 60-37 2 S1O2 = 0,20-0,74; Al^O, = 0,01-014' FejOj" 0,02-0,13. ' '
Dd hoa ning dolomit eo dien phdn b6 hfP, quy mo nhd, fliudng tjo flianh nhtog than khodng c6 chiiu ddy nhd, khodng 5- 15 m, ldn nhdt tdi 25 m.
1.3 Bi hoa tring calcil-dolomit: Loai ndy Id lo?! hon hpp gifla hai loai tten ed mdu tting dvc trdng xdm, dp tting: 82- 95/0, cau t»o khdi den phan Idp ddy hat m p den ttung btah. Thdnh phin khodng v?t (%): dolomit = 10-45; calcit = 55-90 tl^ch anh vd khodng vjt qudng rdt hiim gSp. Ham lupng (%): CaO = 39 83-52 72- M ^ - 2,0-13,47; SiOj - COS-O^!
FejOj = 0,01-0,05; AliOj = <0,01-0,14.
112
y Dd hoa tting dolomit va dd hoa tting calcit-dolomit cd dd nguyen khdi cao, cd flie lam da dp Idt, ttang tii, dd my ngha cap cap. Loai cd dp nguyen khdi flidp cd flie nghien bpt, sir dpng ttong cdi t?o mdi ttirdng hodc ldm vjit liSu ehju lira.
Trong tiit tu dia tdng, dd hoa tting caleit-dolomit phan bo d phdn tiip gidp cua hai l o ^ dd tt<n, cd chiiu ddy khdng ion, tii 3 den 5 m vd chiim khdi Iupng it hon so vdi 2 loai dd hoa tiing tten.
2.0|cdilmphSnb6cdcBiSnadhoatt^ng 2.1. Bja ting chtra Oi vii tring: Cdc flian da hoa ttdng da bill diu ndm ttong tap 1 cua he tdng Bdc Son. HS tdng ndy cd flidnh phan chii yiu Id dd vdi, phan bd ph6 biSn, nhung khong liSn tpc suoi sudn nam ddng nam vdm nang Bii Khang, tao nen cac day mil dd vdi ming diSp d vimg Quy Hpp, Quj- Chdu, Tdn Ky vd Con Cudng vol dia hinh karst diin hinh, be mdt caru ldm chdm. Hp ting Bic Son gdm 3 tjp tir dudi iSn nhu sau:
- Tip 1: Cd diSn phdn bo hep, chi g^p d m0t sd viing gdn ttung tdm vdm ndng Bu^Kh^g dudi djng cdc ldp mdng cd chieu ddy 5-25 m. Thanh phdn g6m dd hoa dolomit, dd hoa dolomit-calcit mdu ttang, ttdng xdm, hat mjn diu. Day: 5-30 m.
- Tip 2: Phin bd rdng rdi, ehilm phdn ldn dien tieh dd carbonat d vung QuJ Hpp, Tdn K^. D | c tnmg ciia tdp Id dd vdi bl hoa hod manh, cdu tao khii hoSc phan top ddy, kien mic hat Idn din hat nhd Trong tjp flihih fliodng cdn gJp it ldp mdng dd vdi set mdu xdm sdng xen k?p.
Cdc than dd hoa tting cd ^ nghla cdng nghiip chil yiu ndm ttung tdp 2 Chiiu day tip: 300-350 m.
- Tip 3: Tin t ^ dudi dang cdc chdm da vdl sdt cam don nghifcig hoic dudi dang Id phin nhdn ctia nip 13m; gSm dd v6i mdu xdm, xdm tto den, ciu t?o khii
9
den phdn ldp ddy, kiln Iruc hat ldn dfin h^l oho. Day: 170-200 m.
Cdc than da hoa trdng cd dac difim chung la chi plan bd d phdn dudi ciia tdp 2 va t4p 1 he tdng Bdc Son va phu thugc rat nhiiu vao vi ui khdng gian xa hay gdn cua thanh tao dd vdi so vdi trung tdm hoat ddng magma xdm nl^p, cung nhu do tinh khiet cua thdnh phdn hda hpc dd voi nguyen thuy.
2.2. Hogt dpng magma xdm nhap vd qud trinh hoa hda dd vdi tao thdnh dd hoa trdng: Cac thanh t^o xam nhdp trong viing phan bd da voi he tdng Bdc Son chu
yiu thude 2 phirc he Ban Chieng (Gsy,GDi/E 6c) va Y6 Yfin Sun (G/K-E ys). Chiing tao thanh cac khoi nhd xuyfin cdt hodc tao thanh cac thi batholit ndm dudi dd vdi, phan bd chu yiu d phdn trung tam vdm ndng Bu Khang.
Kit qua ddnh gid dp hoa hod da vdi he tang Bdc Son so voi trung tam khoi xdm nhap (Bang 1) cho thdy mat do diim quan sat gSp da hoa trdng so vdi tdng sd diim quan sat tren 6A vdi he tang Bdc Son cd xu the tdng ddn tir ngoai ria vao phia trung tam magma ciia vdm nang Bu Khang.
Bang 1. Th6ng kg tt I? g$p dd hoa trdng tai cdc vj tri khac nhau ddi vdi trung tdm khdr magma
TT 1 2 3
Vj tri so vdi trung tam khoi magma G5n (<1 km)
Tmng binh (1-5 km) Xa(>5km)
Tong so di6m quan sat
213 71 128
So diiai quan sdt gap dd hoa tiing So diem
93 22 22
Tyls(%) 43,7 31,0 17,2
Nguon tai li|u [I]
[6]
[81 Ket qud phdn ti'ch Idt mdng eho fliiy
kich fliude hat khoang vat calcit, dolomit flidnh tao ttong qud tiinh hoa hoa da vdi cdng cd liSn quan mil fliiet din ttung tdm magma, kl ca flieo chieu ngang vd chiiu flidng diing (Bang 2).
Nhu vay, cac flidnh tao magma trong vimg cd vai ttd quan ttpng ttnng qud Wnh hinh flidnh cdc flidn dd hoa trdng. Chinh qud mnh hoat hod cua phiic nep loi Bu Khang vdi su xdm nhjp manh m5 cua granit d phin nhdn da gdy biin chat cdc dd vdi, ldm sjieh chiing, dl djt dupe dp ttdng. dp tinh khilt cua dd hoa tring. Quy md, chit lupng cdc flian dd hpa tiing cd liSn quan mdt thiit vdi tiung tdm vdm
ndng: nhimg vOng ndm gin cdc khdi magma xdm nhdp kich fliude Idn cd muc dp hoa hod msuih me hon, ty le gdp dd hoa ning ldn hon vd chieu ddj; ede thdn dd hoa tting cung Idn hon, ddng flidi kich fliude cdc hat khodng viit cung ldn hon;
ngupc l|u, nhtog viing ndm xa ttung tdm vdm ndng (xa khdi magma), miic dd hoa h(^ yeu hon, ty 1? gdp dd hoa tiing etog flidp hon va cdc than dd hoa tting cimg cd quy md nhd hon, hat min ban. Thyc tl, cung vi le do cdc flian khodng dd vdi tting' d cdc khu bic, ddng bdc Quy Hpp vd tdy bdc Tdn Ky (gdn trung tdm vdm ndng Bd Khjng) cd chat lupng tdt hon d cdc khu phia nam, ddng nam Quy Hpp,
Bang 2. Tdng hqrp dac diem hjit khodng vft calcH vd dolomit Vjtii
so vdi magma Gin (<lkm)
Trung binh (1-Skm)
Xa (>5km)
So hi^u lat mdng QH065 QH067 QH0156 QHI61 QH164 QH023 QH029 QH043 QH 125 QH 129 QH132 _C!H135 QH022 QH037 QH052 QH056 QH062 OH 063 QH064 OH 120 QH121 OH 122 OH 142 QH148 OH 150
Tendd Da hoa tiing calcit hat ldn Da hoa tring calcit hat idn Dd hoa trang calcit hat Idn Da hoa tiins calcit hat Ion Dd hoa trans calcit hat ldn Dd hoa trang calcit hat vira-Idn Da hoa tiing dolomit hat trung Dd hoa trdns calcit hat trang Da hoa tiing dolomit hat tmng Da hoa ttinp dolomit hat trune Dd hoa trdng calcit hat trung Da hoa tiing calcit hat tinns Da hoa ttdng calcit-dolomh hat nhd Dd hoa tring dolomit hat nhd Dd hoa hing calcit hat nho den viia Dd hoa tiing calcit hat nhd Da hoa hing calcit hat nhd Dd hoa tiing calcit hat tiung Dd hoa tiing calcit-dolomit hat nhd Da hoa tting calcit hat nhd dSn vita Dd hoa tring calch hat vira-Idn Dd hoa tting calcit-dolomit hat nhd Da hoa tting dolomit hat nhd Da hoa tiing calcit hat trung Dd hoa ttdng dolomit hat nhd DS hoa ning calcit-dolomit hat nhd
Kichttiudc hat (mm)
0,5-4 0,3-4 0,5-4 0,5-2,6 0,1-0,2 0,5-1,5 0,1-0,15 0,05-0,1 0,3-4 0,5^
0,2-1 0,1-0,2 0,2-1,5 0,3-1 0,3-1,2
0,4-2 0,1-0,5
0,2-2 0,2-2,7 0,1-0,25 0,1-0,2
0,3-2 0,1-0,15
0,1-0,2
D$c diim khoang v§t calcit, dolomit Hat khoang vdt tu hinh, kich thude
ldn (0,3-5 mm)
Hat khodng vlttu hinh, nua tu hinh;
kich thude tning binh (0,1-4 mm)
Hat khodng vjt it tu hinh, vi hat;
kich tiiudc nhd (<0,2 mm)
^ J ' - T " 1 " * ^ THAM D6, KHAI THAC, CHS B £ N V A St/ DgNG H(?P L* DA HOA
•n«NGVONGTAYNGH$AN
1. Sdn phdm cua cdc md dd hoa bing vd hl#n tifng khal ttidc
Hi|n nay dd hoa ttdng dang dupe sii dimg vdi so lupng ngay cdng ting tiong nhieu nganh cdnj nghiSp, nhu xiy dpng, giiy, cao su, hod chat, son, phdn bdn, fliiic dn gia siic, dupe phdm, vjit U ^ mJ nghe vd mdi ttudng' Cdc nude cd nen cdng nghi?p phdt tiiln ttto .fliS gidi nhu EU, Mb* Ban, Hdn Quic Tiung Quoc, MJ, Han Qudc, Nh^t Bdn, ...
dSu sii dyng cdc sdn phim til dd hoa vdi sd lupng ldn. Chi riftig ttii ttudng My ndm 2003 dS tieu flip khtAig 25 ttipi tin bpt dd 114
trdng sieu min, Canada 2,5 c i ^ tin, Nhjlt Bdnl2tii8utin,...
Theo s6 li§u tit dure t l flidm dd vd khai flidc cdc md dd hoa tting d mien tay Nghf An ta fliiy ttong mdt md fliudng cd cdc loai dd sdn phim sau:
- Dd hoa calcit hojic dd hoa calcit- dolomit ed di uing >80%, dp nguyen khdi tit (>1 m^), cd flil cua cat gia cdng ldm dd dp Idt, sdn xuit d l mJ ngh?, diSu khfc (Hlnh I, 2). Loai ndy ehilm t^ 1? tir 0 din 10%, tuy fliuSc vdo vj ttf md nim gan hay xa khdi magma.
- Bd hoa calcit cd dO tiing >80%
nhung dd nguyta khii fliip, cd flil nghilii
thdnh bdt carbonat calci lam chdt ddn cdng nghi?p. Loai nay chiim ty le 5-30%
tuy thugc tung md.
- E>a hoa mau sdc da dang (ttdng xdm loang Id vang, xam deo,...), cd dg tigayea ldx6i >0,1 m^, cd thi lam da ^ lat (da phifin.
da deo dp trang tri...) (Hinh 3). Loai ndy c h i ^ ty le tir S-40% toy thugc tung md.
- Sd cdn lai trong cac md la da khdng dat cac yeu cau nfiu tren, cd thi lam VLXD tiidng thirdng.
Hinh 1,2. Cdc son phdm chi biin tir da hoa trdng: dd dp Idt ldm ldn mdu trdng (Hmh 1) vd sdn phdm dieu khdc, my ngh? (Htnh 2).
115
J u y nhien, do miic dp diiu tra cdn ban che (todn vung mdi diroc do ve dia chit va diiu tta khoang san ty le 1:50.000), nen vipc phdn ^ n h chinh xdc, eu ttil vl dac diim phan bd, ty le cdc loai di cd khd nang ldm dp lat, nghiin bpt... cho ttog vimg hien nay chua thuc hien dupe.
Hien nay, dd hoa tiing d tay Nghd An dang dupe khai flidc tai hon 65 vi tii khdc nhau, dl sdn xuit da dp lat hodc nghiin min ldm bdt caibonat calci vdi sdn Iupng trung binh khai ttidc hang nam giai doan 2005- 2010 la 1.750 ngdn tin. Tuy nhien, do phuong phap vd edng nghe khai flidc cdn lac hdu, cdc vi m' khai flidc manh mun, nhd li, chua cd phuong phdp fliu hdi dong bp cdc loai dd ttong qud trinh khai flidc, nen nhiiu md chi mdi fliu hdi da ldm dp Idt, ldm bpt, cdn cdc loai dd khdc loai bd, din din flnh tiang flidt fliodt, ling phi tdi nguySn.
2. Kiln nghi
Dl khai flidc, sii dpng cd hipu qud ngudn tdi nguySn dd hoa tting d mien tay Nghe An, dl nghi:
^ 1. Tien hdnh diiu tta, ddnh gia tdng flil tiem ndng, chit lupng vd khd ndng sir dung dd hoa tiing d miin tdy Ngh? An;
khoanh djnh cdc khu cd dd hoa ttdng dat ySu cau ldm dd dp Idt, bdt siSu min, tao eo sd quy hoach flidm dd, khai flidc idioa hpc lo^i khodng sdn ndy.
1. ITu tien sii dung cdc loai da hoa hdng cd dd nguySn khdi tdt (>i m') ldm da dp Idt de nang cao gid tii khodng sdn.
Nhihig vimg ndm bao quanh vd cdch ttung tam vdm ndng Bu Khang tii I din 5 km (nhu cdc viing Chdu Tiin, Chau Quan§, LiSn Hpp, ...), cd tiim ndng dd hoa tting calch ed dp nguySn khii tot can quan tdm diSu tta, quy hoach ttidm dd, khai flidc ldm dd Ip lat mdu tting cd ldn vd fliu hdi dd vpn nghiin bdt sieu min.
dolomit mau tting v4 nhiiu mdu khdc nhau, cin diiu tta, quy hojich flidm dd, khai flidc ldm dd dp lit cdc loji.
4. Cdc san phim khdc trong qud trinh khai flidc cdc md dd hoa tting d miin tay Nghe An edn dupe fliu hdi ldm v^t li$u xdy dung thdng fliudng hodc ldm nguyen liSu san xuat cdc loai v^t lipu khdng nung.
VANU$U
1. Dtah Minh Mpng (CM Min), 1971.
Bao cdo Dja chit vdng bic QuJ Hpp, ty I?
1:50.000. Luu tru Bia chil. Hi Ngi 2. B l Canh Dmmg (Chi Men), 2004.
Bdo cdo Xdy dung ludn cii cho cdng tdc quy hofdi vung dd tting (Juy Hop, flnh Ngh?
An. Luu tra Si Cing nghiip Ngh^ An.
3. Ho Duy Thanh (Chu biin), 2002.
Bdo cdo Ket qud khdo sdt vd tong hpp tdi li?u da hoa tting vimg Quy Hpp, ttah Ngh$ An. Luu trir Liin doin Dia chit Bic Trung Bg.
4. LS Thanh Vmh (Chu biin), 1998.
Bio cdo Kit qud flidm dd md dd vdi tting Chau Cudng, Quj. Hpp, Ngh? An. Luu IrO Dia chit. Hi Ngi.
5. Nguyin Dinh Ndm (Chu Min), 1974, Bdo cdo Dja chat vtog Phu Loi Tan Kj- ty lp 1:50.000. ZTO irif Lien doin Dia chit Bac Trung Bg.
6. Phan M»nh Dflng (Chii Min), 1983. Bdo cdo Dia chit vtog bic Nghia Ddn, ty 1? 1:50.000. Luu tra Liin doin Dia chit Bic Trung Bg.
3. Nhtog viing nim xa vdm ndng Bii Khjng, phan bd phd biin da hoa caleit- 116
7. Tran Cdng Bing, 2006. Bdo cao Bieu tta, ddnh gid tm lupng, chit lupng vd quy hoach flidm dd khai flidc dd vdi ttdng vimg Quy Hpp, Quy Chdu, Tdn Ky yd Cpn Cudng, tinh Ngh? An. Luu tri Lien doin Dia chdt Bic Trung Bi.
,J: l^"" "»" •n>»»8 (Chi Min), 1979. Bdo (^o D,a chit nhdm td Nghla Ddn - Quy Hpp,t^ I? 1:50.000. Luuira Lien doin Dia chit Bic Trung Bi
SUMMARY
Distributive feature of wihitB maible in ttie west of Ngh? An Province: Orientation of exploration, exploitation and use
Nguyin Tiin Thinh The Nghe An Province has great potential in white marble, disttibuted mamly in its western part on flie territory of ttie Quy Hpp, Quy Chau, Tan Ky and NghJa Bdn Distticts, with flie total resources of over 900 miUions tons, mcludmg 3 types- calcite wMte marble (CaO >S2%, MgO <0,5%. Wb >90%); dolomitic white marble (CaO
<35/., MgO >15%, Wb >75-85%) and calcite-dolomitie white marble (CaO <32-50%
MgO >1-15%, Wb >80-95%).
Wute marble bodies are disttibuted in the soutti of tile Bu Khang Uplift Dome formed by flie miubleizmg process of flie Bdc Son Limestone mider flie impact of acnyizatjon of flie Bu Khang Anticluiorimn and diermal impact of inttusives of fte Ban Lhieng, Ye Yen Sun and Sdng Ma Complexes.
At present, white marble in Ngh? An is being explored and exploited in 65 occurrences widi flie total output productivity of over 1.5 million t o j y e a r , but flie mnTei^T "=.^=^=™'- ° [ ^ ™ " ^<^^=. = ^ to cause wastage in mmerals and poor mfluenee lo the enviromnem. TTieiefore, it is necessary to cany om flie survey aiming to assess flie potential and quality of marble for plamung in detiiils flie works of exploration, exploitation, processing and rational use of fliis mineral resource.
Nguai Men tip: Trin Dlnh Sim