Tap chi DIA THAT f^^ rfrlM. l-2nnu|r^,^j
, XAC DINH VAN TOC DICH CHUYEN TUYET D 6 I VO TRAI DAT LANH T H 6 VIET NAM TlT S 6 LlEU VI PHAN
DINH VI TOAN CAu PGNSS)
Bill THI H6NGTHAM
TrudngDgihQcraingiiyenvdMdilrudngHdNdi, Thi trdn Cdu Diin, TiiLiem, HdNpi
f^^ ^ f ' 1? ^- ^ ° ^'^ "'^ '" ""^ '^' **" ^ "ghien cdu cd xu thi dich chuyen 'heo hudng dong-ddng nam (Mdng Cdi 32,0mm/ndm, fl/vS J J MIZ- - ^ ^ ^ ^ ' ^ - f - - va Trudng Sa 24,5 mm/ndn). KitqLnl phu hpp vat cac ket qua da dupe cdng bd cd vi hudng vd dp Idn. Qud V'mhZ lysol„udupc thvc hifn theo quy trinh nghiem ng^t. tpa dp vd S S chuyen cua cac trgm dgt dp chinh xdc vd lin cgy ego, gdp phdn pMc Vpabt tranh d,a dpng lvc hiin dgi lanh thd Vift Nam ngdy mpfhMifn . , . . . . , , ^ , "^^ e^y Song Hong, Difn Bifn. Sdng Dd Nghien cuu ddnh gid vdn toe dich vd Son La [6].
chuyfn vd Trdi dit Idnh tfii Vift Namdd Trf„ . „ / , - . * . dupe mdt s i tdc gid di cgp ttong cdc cdng Jf^l ^\ \ T ''^^ 'I"* "8^1^" =™
trinh cdng b i khdc nhau hi L i 2S;o * ' ^^^ ' ^ ° ^^^^
[2,4.5.9]. Ddng luu y nhit Id: - Cdc nhd khoa hpc Vift Nam dd nh§n
^ - Nghifn cim chuyin djch cua vd Trdi %\ ? " ' " ' ^ t^ *'^^ ^"^ ^"^^ ^ "?"
dit dpc tfieo diit giy U i Chdu - Difn T . ^ ^ " ^ " ^ " " ^ ^"^ '''"^ '^''"y^" ^*
Bign [2]; * 1 rdi ddt.
Xdc djnh vgn tic djch chuyin vd ' f/ "^^^ ^ "^ ''^ '*'^'" ^PS chii Trdi dit flieo s i lifu do GPS lien tuc Z ^u" ^^ "i™^ ^ "^'^ ^"^ ^^^ ri8ng rS.
3 diim Hd Ndi, Hui vd tfidnh phi Hd P?^'=J^;i i^*" "^ "^hifn ciiu chuyfn sdu Chi Minh [4]; ^ ^f <=huyen dpng hifn dgi vd Trdi dit, chii vs„ .A. J .. u I , ^^" '^ ^^^^ ^^^y^'^ ''Pc theo hai cdnh cua _ - V ^ tie dich chuyin tgi mdt s i diim ^^ gdy.
hen Biin Ddng. 1dm sdng td chuyin djch M^, „A; K«. U
kiin tgo hifn dgi tten khu vyc ndy fSl- nJol 4 * *=''""8 nhit Id cdc diim XAc Hinh AU X. ^ , ,^ . '*"''*' *'^* '^P ''°"g thdi gian qua tgi t r o n g ^ t o o ^ S '^7^'' '" ^ ^ "^^ ^''' . " i r '^'' y^" '^ ^ * « vd clii vS
r^syrnL^r9rvdToofic^ zx^^s'^t.zr^o^:
&t*SoTv?r9r^--"- S;:;:tK^th^l^^^
t^J' P " ^ V' ' ^ ^ tho vd ciing chua cd ttgm Tir dii lifu ndm 1994 din ndm 2007 "^° '*'^"'"= "^y ''vng c i djnh vdi da cua 27 ttgm GPS d phia Bdc Vift Nam '"^'^ *'=*'•
dich chuyen hiyft doi ciia cdc diim dd Mgng ludi GNSS lifin tuc fhn ,hA„„
tri ddc trung trfn toan lanh flii la budc tifn ndi bat vi quan trie GPS da muc dich. Mgng lutii qudc gia nay, budc diu.
gdm 4_cum ttum kien cd tai Mdng Cai, Dd Ndng, Phii Qudc vd Trudng Sa.
Chiing dupe xay dung theo tieu chuin cua IGS, phyc vu da myc dich: xdy dung hf q^uy chiiu, nghien ciiu dja ddng, djnh vj dan dudng...
Trong khudn khd bdi bdo ndy, cac tdc gid butjc diu khai tfidc tai lifu do lien tuc qua cdc tfidi ky 2010, 2011 va 2012 nhdm xac djnh van tic djch chuyin tuyft ddi vd Trdi dat (djch chuyen ngang vd thing diing) tai Mdng Cdi. Da Ndng. Phu Qudc vd Trudng Sa.
II. SO LIEU
; ^ H f tfidng ttam DGNSS/CORS dupe .%^k lap phyc vu cho vifc xdy dyng Hf
quy chiiu vd He tpa dp quan sy gdm cdc ttgm Mdng Cdi (MCRS), Da Ning (DNRS), Phii Quic (PQRS) vd Trudng Sa (TSRS) [1]. Cdc tt3m ndy cd 2 chirc ndng chinh: 1/ chiirc ndng CORS (do tfiudng tryc di phyc vy cho cdc myc dich nghien cihi dja dpng lyc, ddnh gid cdc chuyin dich mdng. xay dyng khimg quy chiiu dfng, cdng tac khdo sat do dgc,...);
2/ chiic ndng DGNSS (phdt so cdi chinh ndng cao dp chinh xdc djnh vj va din dudng cho cdc phuong tifn di dpng) [1].
Vdi chiic ndng tram CORS, mdy tfiu hai tan sd vd anten chong phdn xg ddm bdo chat lupng so lieu cho cdc xir ly tuong ddi.
Vdi chirc ndng DGNSS, day Id cdc trgm do lien tyc, hogt dpng ding thdi ciia mdy ddng vai trd Id ti^m chu (cdn dupe gpi Id trgm co sd hodc trgm tham chiiu, dd biit t<?a dp cung vtii ma trgn phuong sai vd hifp phuang sai); mpt hay nhiiu mdy thu ddng vai trd la trgm dpng (rover).
Cac mdy thu sd lifu ddng thdi, cac sai s i pho bien nhu Id sai sd ddng bp cua ddng ho vd sai sd dd ti% ciia ting khi quyin,...
dupe xac dinh tai tram chu va dupe hieu chinh vdo thdnh qud tai tram dpng thdng qua ket ndi true tiep may chu-may dpng.
DGNSS cung cdp tpa dp ciia tram dpng lien quan din tram tham chiiu boi cdc sai phan da dupe hieu chinh cdc sai si, vi vay dp chinh xdc cua tpa dp diim dpng dupe cai thifn mpt each co ban, dap iing dupe cac nhiem vu dinh vi.
Sd lieu dang Rinex cua cac tram Mdng Cdi, Da Ning, Phii Quic vd Truong Sa da dirpc thu tbap va kiem tra. May thu dupe su dung la TRIMBLE NETR5 va anten TRM55971.00 vdi 6 logi tii do ma, pha vd Doppler ti^n hai tin sd (Ll L2 CI P2 DI D2). Ddy Id cac thdng si co ban dam bdo chit lupng s i lifu di cd tfii xu ly tuong dii. Tgp hpp s i lieu cac ca do 24/24 gio da dupe tdc gid tfiu thap, lya chpn ciing vdi cac diim IGS Idn cdn (diim KUNM, i m i S , PIMO, WUHN) dua vdo xu ly ddng thdi nhdm xdc dinh tpa dp tgi cdc thdi diem vd tir dd xdc djnh van tic diim.
III. PHirONG PHAP Xir Lt
Bernese 5.0 Id phin mim dn djnh, cd khd ndng cap nhat, sir dung hang logt cdc si, dii lifu ho tiy (Ijch \e tinh chinh xdc, tdm pha anten (may thu, vf tinh), chuyin dpng eye, dia tiiiu, tfniy tiiiu, md hinh khi quyin....) va xu ly cdc tii do GPS vdi dp chinh xac cao [7, 8, 9]. Phin mem ndy da dupe khdo sdt img dung trong tfiyc tien d nirdc ta, d ^ iing yeu cdu cho vifc xir ly so lifu ciia cac tram DGNSS/CORS.
De dgt dp chinh xdc vd tin cdy cao.
ngodi sd lifu do dd di cgp d tten. cin khai tfidc vd cap nhdt cac s i lifu ho try qudc ti sau:
.- sd, da lieu ctia cdc diim IGS: Cac diem IGS Idn cgn nude ta dupe su dyng nhu cac diim khing chi ciia hf tfiing ludi cd dp chinh xac cao tim quy md todn ciu.
Tir cac diim Uidng chi nay ta cd tfii khai tfidc cdc tfp sd lifu GNSS vdi tpa dp ciia cdc diim dupe cdng bi ttong ITRF. cimg
47
cdc sd lifu do dgc de xac djnh tpa dp;
thf m cdc dii lieu vf van tdc di danh gia vgn tdc djch chuyen cua cdc diim. Day cWnh Id van tic dich chuyin tuyft doi tron| mdt hf tpa dp thing nhit todn ciu cd gdc tpa dp d tdm Trai dit.
Lich ve tinh chinh xdc (Precise Ephemeris): So lifu dupe xii ly theo Ijch vf tmh qudng bd hodc lich vf tinh chinh xdc. Lich ve tinh chinh xdc dupe xdc djnh tten CO sd: Md hinh chinh xac cho tinh chuyin cdc he quy chiiu; Md hinh chinh xdc bieu dien cdc dnh hudng cua cac di
tfiudng tdi vf tinh ciing nhu diim do; Tog dp chinh xac tixmg ITRF cua diim quan tide ve tinh; Phin mim xii ly; Mo hinh sai sd dO fre khi quyin hieu qua; Md hinh dp lyc bdo mat ttdi; He tfidng cdc diim quan ttdc lien tuc vtii quy md toan ciu, tfiu tf%
sd lieu vdi chat lupng cao. Vdi cdc dJc difm neu ttfn, lich ve tinh chinh xdc ddp ling duac nhifm vu djnh vj tt^n khdng gian Idn cd dp chinh xac cao, va dupe khai tfidc di xii ly s i lifu ttong nghifn ciiu nay.
STT Ngiy 01/12/2010
Ng4y cua
02/12/2010
10 I I
14
03/12/2010 04/12/2010 01/06/2011 02/06/2011 03/06/2011 04/06/2011 05/06/2011 01/03/2012 02/03/2012 03/03/2012
335 336 337 338
MCRS
• T6ng hqrp s6 lifu xir ly Ten di&n DNRS PQRS
152 153 154 155 156 61 62 04/03/2012 05/03/2012
63 64 65
J ^ <
TSRS
Cdc tham sd quay aia Trdi d ^ Hf ttiic
^ d § dupe djnh nghia tfieo vj tti bung buih H hudng ttuc quay Trdi dit Trong tfiyc ti.
chuyfn dpng eye rat phiic tgp, tfieo quy dgo hinh sin CO cdc chu ky ngin vd chu ky ddi.
Vdi yfu ciu dp chinh xdc cao cua n ^ a i oiu djch chuyfn vd Trdi dit, cdc dnh hudng ndy khong flii bd qua. Vi vay t i chiic riRS (International Tenestrial Reference System) quan ttdc vd cdng bd cdc tfiam s i quay cOa Trai dit hay vj tri ctia ttvc tgi tiing flidi diim nhdm hifu chinh kit qud xii ly. Cac tfiam si quay ctia Trdi dit dupe khai fliac tir totemet vd c ^ nh^t vdo phin mim xir ly.
- Cdc tham so khi quyin: Khi quyin vi CO bdn dupe chia Idm hai ting: ting dii luu (ttoposphere) va ting difn ly (ionosphere).
lOii xu ly si lifu GNSS cd dd chinh xdc cao cin phdi quan tdm tfu'ch dang tdi vifc md hinh hod cdc ting khi quyin hifu chinh cdc dp tte vdi df chinh xac nhit djnh nhdm nhgn dupe cac tfidnh qud GNSS ddm bdo chit lupng Di tiin hdnh xir ly, dp ti^ khi quyfn cd tfii xdc djnh dupe tir si Ueu GNSS hodc khai tfidc md hinh khi quyin todn cau tir cac t i chiic quic ti. Tuy myc dich nghifn ctiu di xdc djnh cdc tfiam si ddc tnmg cho ting khi quyin.
KUNM NTUS PIMO WUHN
J
- So lieu tm trong triiu diii duang (Ocean loading): Tdi ttpng ttiiu dai duong cd nguyen nhdn tii biin dii tfieo tfidi gian ctia sy phan bi vdt chit cua khii dgi duong vd lifn quan < ^ chuyin dpng vd Trai dit Thay dii vj hi do dnh hudng ciia tdi ttpng ttiiu dgi duong cd tfii dgt din 100 mm.
Tdi ttpng triiu dgi duong hrong ty nhu dja hif tl, bj chi phii bdi nhdt ttiiu vd ban nhdt ttieu nhung cd kit qud tu; ttpng tdi cua tfiiiy ttieu dgi duong tt«n lap vd Trdi dat. Tai tfidi diim djnh vi don mirc dp chinh xdc Id 5 cm, miic dp mm cho djnh vj tinh tt^n 24 gio hodc d cdc ttam xa dgi duong, mirc dp cm dii vdi djnh vj diim dpng hodc djnh vj tinh dpc theo vung ven bien ttxing khoang tfidi gian quan sdt nhd hon 24 gid, dnh hudng nay dupe dua vdo tinh toan [3].
Vifc xu ly so lifu dupe tfiyc hifn tfieo trinh tu sau:
Lgp Ifch do: Ljch do giiip ngudi xu ly khai tfidc chinh xac, diy dii ljch vf tinh chinh xdc, cdc dii lifu ho trpr, quan ly vd theo ddi dupe qud ttinh xu ly (tfidng s i hch vf tinh, ngay ttong ndm,...).
49
- Lap Project, thiit Idp cdc thu muc, cfp nhgl cdc tip sd lieu vdo thu muc thich hpp: Thu thiq) va tgp hpp tfp s i lifu va cdc tfp s i lifu ho tto phin mim hogt ddng. Cap nhat sd lieu do, ljch vf tinh chinh xdc, cac sd lieu hd ttp, md hinh dien ly vdo cdc thu muc thich hpp.
,-Xuly theo timg budc theo trinh dan din kit qud binh sai: Qua ttinh xOr ly bdng Bernese yfu ciu dgng dii thoai ngudi-
r
may. phdi tgp ttung cao. ddm bdo khoni!
sai sot cdc tfidng so diu vao-ra.
Kiem tra kit qud xir ly: Phin mem hogt dOng tfieo nguyen tdc chi cd tfif di tiep khi budc ttudc dd hodn tfidnh. Tuy vgy vai frd ciia ngudi su dyng la kiim tta kft qua xii ly cd tfif chip nhdn, di tiip hay phdi xu ly Igi. Viec kiim tta nen tfiyc hifn ngay sau tiing cdng dogn.
Bang 2. Tpa a^ cOa cac diim DGPS/CORS
Bdng 3. Vjn t6c chuyen djch tuyft a6i cQa cdc ailm DGPS/CORS
: T T T - T ^ ^ ^ T ^ ^ 15], 16] vd t9J
i
Ghichd
neo Chieu thdng dung; V Id tdc do dich chuvin cdn -*,i».
IV. KCT QUA
'< Sii dyng sd lifu tfiu tfigp dupe tgi cdc 11; difm do dgc lign tuc Mdng Cai. Dd Ndng, list Phii Quic vd Trudng Sa qua ba tfidi ky:
E(, ndm 2010, 2011 vd 2012. Tren co so phan J^ ttch s i lifu nhu da ttinh bdy tai myc R, 1^ chiing tdi da xdc djnh dupe phuong dich
chuyin, van tic djch chuyin ngang vd tfiing diing vd Trai dit tai cac diim DGNSS/CORS, ttinh bay d Bang 2 vd P Bang 3 vd cho tfiiy:
S^ - Vd Trai dit tai Mdng Cai cd phuang 1^ djch chuyin ddng - ddng nam vdi van tic 1^ 31,8 mm/ndm. Van tic dich chuyin thing
diing Id 45 mm/ndm.
^ ^ L - Phuong djch chuyin cua vd Ttdi dit j ^ ^ ^ D d Ning Id ddng - ddng nam va vdi
^ v$n tic dgt 40.3 mm/ndm. Gid trj van tic
^ djch chuyin tfidng diing Id -1,8 mm/ndm.
^ - Phuong djch chuyin ciia vd Trdi ddt
;: tgi Phii Quic Id ddng - ddng nam vd van tic djch chuyin ngang vd tfiing diing R^ hrong img Id 24.4 mm/ndm vd 11.8
mm/ndm.
- - Tgi Trudng Sa, phuong djch chuyin 7 vd Trdi dit ciing hrong ding vdi cdc diim - ttfn dit liin, ddng - ddng nam. vd vgn tic 'r djch chuyin ngang vd tfidng diing hrong
ling Id 24.3 mm/ndm vd -5,9 mm/ndm.
Dii sdtfli kit qud nghifn ciiu cua tdc gid ttong bdi bdo ndy vd cdc nghien cihi tiirdc ddy [5, 6, 9] (Bang 4) cho tfiiy sy tuong ding vi phuong djeh chuyin vd gid tii hiyf t doi ciia v|n tic djch chuyin ngang. Chiing tdi ciing dd xdc djnh dupe vgn tie djch chuyen thing diing vd Trdi dit tgi cdc diem nghien ciru vdi sai s i nhd. Tuy ddy mdi chi Id nhimg kit qud binic diu, cin dupe kiim chiing song cd
•y nghia khoa hpc trong nghien ciiu dja dOng lyc hifn dgi Idnh tfii Vift Nam.
V. KET LUAN
Tu cac ket qua nghifn cuu ciia chting toi, cd tfii dua ra mot s i nhan djnh budc diu nhu sau:
Hifn tgi vd Trai dit Idnh tfii Vift Nam cd bieu hifn dich chuyin to net tfieo phuong ddng ddng nam. vdi van tic bien ddng trong gidi hgn 31-41 nmi/ndm.
- Co su dich chuyen vd Trai dit khdng ddng deu giiia cac viing miin tten lanh tfid Vift Nam: tgi khu vyc Miin Trung dgt gia ttildn nhit, cd 40,6 mm/ndm tai ttgm Da Nang; tgi Mdng Cdi Id 31,8 mm/ndm;
tgi Phii Qudc Id 24,4 mm/ndm vd tgi quin ddo Trudng Sa Id 24.3 mm/ndm.
- Cd^ biiu hifn van dOng nang khdng dong deu vd 'Trdi dit lanh tiii Viet Nam.
Gid hi van tic nang tiiyft ddi vd Trdi ddt tai Mdng Cai Idn nhit. dgt 45.0 mm/ndm. tai Phii Quic Id 11,8 mm/ndin.
Xu tfif syt liin vd Trdi dit Idn nhit tgi Trudng Sa, dgt -5,9 mm/ndm. tgi Da Ndng Id -1,8 mm/ndm.
Cdc gid tti vi phuong djch chuyin vd gid tti vgn tic djch chuyin ngang theo kit qud tinh todn cua chiing tdi trong bdi bdo ndy Id khd phu hpp vdi cdc kit qud nghifn ciiu ttirdc dd. Vi vdn tic djch chuyin tfi^g diing vd Trdi dit flii day Id nhihig ket qud diu tifn, cd flii cin dupe kiim chiing trong cdc nghifn cihi tiip flieo.
VAN Lifu
1. B§ Tong Tham Mmi - Cyc Bdn Di, 2008. Hf quy chiiu vd Hf tpa dO qudn sy. Hf tfiing vd gidi phdp cdng nghf. Hpi thdo khoa hpc.
2. Duong Chi Cong, Tran Dinh To, 2007. Estimation of ITRF 2000 velocity field across tfie Lai Chau-Dien Bien fault ui Nortfiwest of Viettiam, 2002-2004 International Symposium on Surveying and Mtqtping for Sustainable
51
InPI Development. Hanoi, Vietnam, 27-28
March, 2007
3. Gfrard Petit and Brian Luzum, 2010. lERS Conventions (2010).
International Earth Rotation and Reference Systems Service (lERS).
4. Le Huy Minh, Kui^ Feigl, Frederic Masson, Domig Chi C6ng, Alain Bourdillon, Patrick Lasudrie Duchesne, Nguyen Chien Thdng, Nguyen Hd Thanh, Tr^n Ngpc Nam, Hodng Thai Lan, 2010. Djch chuyin vd Trdi dit tfieo si lifu do GPS lifn tuc tgi Vift Nam vd khu vyc Ddng Nam A. TC Cdc KH vi TD. 3: 249-260 Hd Npi
5. Phan Trpng Trjnh, Ngo Vdn Liem, Tran Dmh To, Vy Quoc Hai, Nguyin van Hwdrng, Hodng Quang Vinh, Biii van Thom, Nguyin Quang Xuyen, Nguyin Viit Thugn, Biii Thj Thdo, 2011. Tic dp chuyin dpng kiin tao hifn dgi tt^n Biin Ddng va khu eye Idn cgn tfieo chu ky do GPS 2009-2010 TC KH&CN Biin. 1:15-30.
SUMMARY
Bui Thi Hdng Thim
h a v ? L : ^ d i t r , Z ! r ' b v T r ' ' V J ""^ '^'^•"^ ^* D G N S S / C O R S stations 2 0 1 0 . 2 0 1 1 . ^ ^ 1 2 A c e ^ r r t h T"- " " ' " ' ' """'' * ^ '""'"^ - *« ^ - ^ East-Soutfi^tw^ at ! ^ f ' " ^ ' " '^^ 'J.^''^ ''''°''' * ^ ^^^y area tends to move nun/year. P M ^ e t^TZL ''^'^'^^^ ^di 32.0 mm/year. Dd Ndng 40.6
been carried out in ace^rf^rv^ h ^ , T '"'^ ^''""- '^' '^'^ ^'°'^'^^^ has velocity of tfie s t a t i o ^ ^ S Z h * ' T ^ ' ' = * ' '=°°''^^'^'' ^^^ '"°v^-«=nt oftfiemod^ngeodyn^r^pie'S^erfrt^r^^^^^^^^
Nguai bien tdp: PGS TS Cao Dinh Triiu.
6. Tran Dinh To, Nguyen Trong Yem, Duong Chi Cong, Vy Quoc Hai.
Znchiewicz Witold, Cuong Nguyen Quoc, Nghia Nguyen Viet, 2012. Recent crustal movements of nortfiem Viettiam fi-om GPS data. Journal of Geodynamics in Press.
7. Teferie F.N., QrUac E.J., and Bmgley R.M., 2007. An assessment of Bernese GPS software precise point positiomng using IGS final products for global site vdocitie&GP5 Solutions Vol 11. pp. 205-213.
8. Supriya Likhar, Madhav N Kulkarni V.S., Tomar, Praveen Pillai,' 2002. A comparative shidy of results fiom GPS data processing software. Trends in GPS data processings. Bombay.
MUMBAI, India
9.^Vy Quic Hai, 2009. Xdc djnh djch ehuyen tiiyft doi khu vye ludi GPS Tam Ddo-Ba Vi. TC Dia chdt. A/311 22-30.
Hd Ndi
