IAM D O KHAI THAC D A U KH[ Sy can thi^t phai thu n6 Igi dia chdn 3D va xa ly tai li§u bang cong ngh§ cao phu hap voi dieu kien dja chdt dgc thu mo Bgch Ho trong giai dogn tgn thdm do KS NguyfaOinhHdf[.]
.-IAM D O - KHAI THAC D A U KH[ Sy can thi^t phai thu n6 Igi dia chdn 3D va xa ly tai li§u bang cong ngh§ cao phu hap voi dieu kien dja chdt dgc thu mo Bgch Ho giai dogn tgn thdm KS.NguyfaOinhHdf TdmtSt Cdu tao Bach Hd Cdng ty Ddu khf Mobil (Hoa Ky) phdt hiin bdng tdf Iliu dia chdn 2D vd giing khoan sdu Dm kiim ddu tiin (Wildcat) BH- IX phdt hiin ddu khf tU tdng sdn phdm Miocen vdo ndm 1974 T^ nhCfng ndm 80 cda thik^ trUdc din nay, Lidn doanh Viit - Nga (Vietsovpetro) dd phdt hiin thdm cdc ddl tuang mdi quan trpng nhumdng chita ddu md Bach Hdvd dang tiip tuc thUc hiin tim kiim thdm dd vd khai thdc md ndy SUklin quan trpng nhdtH dd phdt hiin vd khai thdc ddu khf dd mdng granite nuY n^ trUdc Di tam; cdc tdng sdn phdm dUac xde dtnh nim dd mdng nCft ni vd dd trdm tich b cdc tudl khde nhau, b cdc dd sdu khde Sau mdt thdi gian ddi khai Hide ddu vdi khdi lugng Idn th) sdn luang khai thdc tai md hiin dd qua dinh diim vd dang bgiai doan suy gidm, hdn nCfa viic ban mdt khdi luang nudc tuang tu vdo via Idm bdc tranh phdn ltd ddu - nUdc tai md Bach H6 tfiqy ddi manh Hiin nay, Vietsovpetro vSn dang silf dung tdi lidu dfa chdn 3D thu nStCfndm 1992 (khi md mdf duac dua vdo khai thdc) didiiu chinh mang ludi cdc giing khoan phdt triin md nin vlic liin kit tdi liiu giing khoan vdi tdi Iliu ^la chin rdt khd khan SU kiin giing khoan BH- 19vd cdc gling khoan khde cho thdy tfnh phdfe tap eOa md d6ng thbi cung dil tiim ndng ddu cdn dn chda bnhijfng vj tri khde vd dd sdu khde edn duae Idm sdng t6.Dodd tdiliio dia chdn 3D hiin dang dung khdng ddp Ung duac ydu cdu nghlin edit vd sdn xudt, cdn phdi cd tdi liiu gidu thdng tin vd dp chinh xde cao mang tfnh ddt phd vd phd hop vdi cdu trde dia chdtphUc tap eda md Bach Ho Cdng nghi thu nS vd xCtl^ dia chdn hiin dai gidp cde nhd dia chdt thdo gdnhOng khd khdn gap phdl ddng cdc tdi lieu theo cdng nghi truyin thong, dd tdi ll^u nin tdng quan trpng di nghiin cdfu dia chdt cho phdt triin f^f md Id tdi liiu dia chdn 3D cdng nghi cao; thu n6 dia chdn 3D nhiiu gdc phuang vi hay gdc phUcmg vf rdng; xilf bit ding hudng nghiin cUfu ndt ni vd xCf 1^ tdp trung da diim eho nhvfng vung dia chdt phdt tap, doi tuang nghiin dia n&m bsau Id nhitng cdng nghi mdi cdng nghi thdng tin phdt trien manh nhufng ndm gdn ddy vd dd dUac dp d u ^ sdn xudt Ndi dung bdi bdo neu lin sU cdn thiit phdi thu ni lai dia chdn 3D vd xAf^ tdi liiu bdng edng nghi eao, ddp (iUff edng tdc thdm dd vd khai thdc ddu khfbmd Bach Hd giai doan Min \ 14 DAU m l ' S P 4/2012 PETROVIETNAM 1.M£fdau Md Bach Hd n l m bdn trCing Cdu Long thupc khdi ning Trung t i m cd t i l m n l n g d l u cao, cd vj tri thuan Ipi eho cdng t i c tham dd, khai t h i c d l u Md eieh Tp Vung Tau 125km ve hudng Ddng - Nam, eieh bP noi gan nhat 70km, dp siu nUdc b i l n 50m (Hinh 1) D i y l i loai md cd t i n g chda dac biet khlc vdi cle md thdng thudng - mong granite ndt n l trudc D l tam chda d l u d dd sau t d 3.000m trd xudng Tuy d i l n tfeh md khdng rdng, nhung chieu day t i n g sin p h l m ehda khdi lupng d l u Idn va thupc loai md Idn t r i n t h i gidi Dlu thd Bach Hd ft luu eung khie nen che dp khai thic v l bom i p gap khd khln Vile xlc djnh ele t h I u kfnh c i t chda dau tram tfch Miocen, Oiigocen v l d c vdng ndt n l ehda d i u mdng di dua gilng khoan v i o dung vj tri l i mdt thach thdc D i l u ky la eda t i n g ehda mdng ndt n l p h i t hiin d l u I I khdng ed nUde diy Do d i khai t h i c dupc g i n 200 tri^u t i n d l u , mpt khdi lupng IPn khf ddng hlnh v i tuong ty mdt khdi lupng Idn nude b i l n daac bdm v i o md n i n tinh tr?ng phin bd dau khf v i nUdc Idng d I t da thay ddi ding ke ma khdng the xlc djnh dupc blng t i i liiu dja chin 3D thu no nam 1992 hiin dang sddung huynh, ty trpng nh?, l i loai d l u tdt, ed g i l trj thUdng mai Vile bom I p khdi lupng Idn nude biln v i o via de eao Nhi m i y Lpc d l u Dung Q u i t mdi b i n giao di v i o sin tri i p suit neu dung vj tri, ddng dp siu v i ddng e h l dp l i xult thuong mai cudi n i m 2010 dupe t h i l t ke t r i n eo sd mdt thinh cdng Idn, khai t h i c dupe tdi Uu lUdng dau khf chit lupng dau thd Bach Hd VI viy, ngudn d l u v i o niy eOa md Tii lieu dja chin 3D thu nd l l n dau (nam 1992) can dUdc cung d p d l y du v i l i u dai k l ei Nhi m i y edn nghIo thdng tin nut n l v i t i i lieu gieng khoan co dp md rpng edng suit siu han c h l , t h i l u t i i lilu dja ehIn 4D p h i n anh trung thyc tinh trang via dau, nhlt l i da ed suthay doi manh Sin lupng khai t h i c d l u khf tai md Bach Ho da dat d i n dinh d i l m (13,5 t r i i u t i n ) v i o d c nam 2002,2003 v i hiin dang khai thac P giai doan cudi, sin IUpng khai thac dau g i l m d i n , d mde t r i i u tan nam 2010 Nhilu gilng khai t h i c d i v i dang ngap nuPc hoac ngUng lam viec Mac du vly, v l n d l thu nd lai dja chan 3D, 4D tren t r i n toan md Bach Hd ehiia dUde ehd y de phuc vu eho edng t i e quan ly va tai p h i t trien md nham khai thac tdi da lupng d l u cPn lai, keo dai dPi md, n i n g cao hiiu q u i khai thac md 2, Tinh trang md Bach Hd Trin md Bach Hd h i l n dang cd d l y du he thdng khai thac bao gdm: cac gieng khai thie, eie gilng bdm ep tri i p suit via tdcae gian cd djnh MSP va eie gian nhe BK, he thdng dUPng dng v i n chuyin d l u khi, d p dien n g l m , h i thdng xd ly so bp d l u khai thac t r i n gian cong nghi, he thdng lUu trd d l u v i x u l t d l u thUdng pham FSO phin bd d l u - nude nhu hiln Nlu viec bo tri cac gilng khoan khai th^c v i bom ep ehua hop ly thi cd mpt lupng d l u bj bd q u i n n i m lai via Phan dau khf tfch tu cao pham vi md d i g i i m di d i n g k l sau nhieu nam khai thie da lam thay ddi tfnh chit via, tinh chat vat ly va do thdng tin dja ehIn cung thay ddi Tin sd, bien dp phan xa, tinh liin tue true ddng pha t r i n be mat p h i n xa se khdng ePn nhu t i i lieu eu, dan d i n khd khin liln ket tai lieu dja chin vdi t i i liiu dja v i t ly gilng khoan cua d c gieng khoan sau niy Tai gilng BH-19, d l u dupe phat h i l n d dp siu 4.331 - 4.861m TVDSS, tdc la t h i p hon dp sau trUdc day d i xie djnh d khu vyc vPm Trung t i m md Bach Hd Cac gilng khoan khie eung eP nhdng sy kiln rieng noi len sy phong phd eda t i n g ehda md Bach Hd, can lam sing td t h i m eie vj trf ehda dau edn ehUa dUpc p h i t h i i n D i n nay, chUa thu nd lai dja chin (4D] b l n g ePng nghe mdi nhat de co tai lieu chat lupng cao eung d p thong tin Mo Bach Hd l i md d l u thudc loai Idn Cac ddi tupng t i n g chda va phan bd d l u - nude can thiet cho nghiin khai thac bao gdm t i n g mdng ndt n l , tram tich Oiigocen, edu v i d i l u ehinh mang lUdi cic g i l n g khoan khai thac Miocen Cie gieng khai t h i c d t i n g mdng g i i m Idu lupng v i bdm ep Viec khai thac tai lieu dia chan chd yeu van v i n g l p nude nhanh Cac ddi tUdng tram tieh chu y i u l i chl I I ve b i n cae t i n g ranh gidi chuan d e don vj dia cae t h i n d t co chieu d i y khdng on djnh va dang t h I u t i n g SH-3, 5, 7, 8, 10 va mdng, ehua khai thac h i t d c kinh khd xac dinh Sin lupng khai thie d l u d e l e ddi tuong thdng tin dja chin v l b i l n dp, t i n sd, tdc dp cho nghien tram tieh n i m d d e dd slu v i tudi khae nhau, chilm ty I I edu chi tiet dja t i n g , thach hpc, dp rdng, dp bao hda, h i nhd so vdi sin lypng thu daac d tang da mdng ndt n l sd Poisson ddi vdi eac t i n g chda t r i m tfeh v i Do he thdng ddt gay cd b i l n 66 Idn theo cac huPng khie mdng ndt n l cho nghiin cdu dja c h i t dieu h l n h chia d c khdi biet l i p va dp slu chda d l u khai thac v i q u i n ly md D4UKKI 30 ./2012 15 J THAM DO - KHAI THAC D A U K H I ••'•*! ? H i l n nay, p h l n t r i l n vpng d l u kh( cdn lai x l c djnh trir CO sd t i i li^u dja ehIn thdng thudng l i eye ky khd khln Mic dd da ed nhilu g i l n g khoan, n h i l u thdng tin dja chll bd sung d l ehinh xic hda nhUng t l i ll^u dja ehIn vln Ih f* t i i li|u l l l n k i t c l n t h i l t d l sddyng cho n g h l i n cdu \ q u i trinh p h i t t r i l n md Khdng t h i g i l l q u y l t vi|c nghiSn cdu chi t i l t v i ehinh xie eao v l dja t i n g , thach hpc, rdng, dp t h i m , dd bao hda eho elc t i n g slu ddi mdng ndt n l n l u khdng c6 t i i l i | u dia chin 3D chit luong eao k i t hpp vdi t i l li^u g i l n g khoan ^'"' — • / D n h trang t i l li^u tfla c h i n m6 Bach Htf Clu t^o Bach Hd dupe p h i t h i l n b l n g t i l li$u dja chin 2D Cdng ty Dja v | t ly GSI thu nd n l m 1974 d mgng ludi X 4km Sau n g i y m i l n Nam h o i n t o i n giii phdng, Hinh Bdn dd vi trikhu vpcmd Bach H6[9} n l m 1978, Tdng eye D l u Vilt Nam quylt dinh tifti h i n h k h l o sit 731km tuyIn dia v i t ly mang lUdi 2D chi CP mpt khP k h i n tdn t^i nghlin edu dja c h i t md Bach Hd l i l n quan d i n lien k i t sd lilu dia chin vdi t i l t X km d Bach Hd khudn khd hpp ddng thu n6 dja v i t ly vdi Cdng ty Dja v i t ly GECO, Nauy Nim 1985, sd li^u gilng khoan & p h l n trung t i m md, ndi ed m i t Vietsovpetro d i k h i o s i t 552km t u y I n dia chin 2D dan dp gilng khoan cao, thu n h i n duoc nhilu t i i l i l u gilng d i y xen k l vdi mang ludi trude d i y GECO thuc hien khoan de nghiin cdu Uu d i l m cda t i i l i i u gilng khoan d l tao mang ludi 2D ehi t i l t hon 0,5 x 0,5km vdi muc la cP dp p h l n gilt t h i n g ddng eao, chinh xic, nhung chl dfch thu nhan dupc tai li|u minh g i l i t h u | n loi hOn (Hlnli ed g i i tri Idng gilng khoan va vdng xung quanh 3) Nhyng cdng t i c d i m b l o h i n g h I i v l ^ n h vj h^n g i n than gilng khoan Ra xa khdi g i l n g khoan v i siu hdn c h l n i n khPng dat dUdc khoing cleh ddng deu giQa day gieng khoan khd lien k i t cic gieng khoan khlc vdi cic tuyIn thu nd Cung chinh nhi]mg t l i lieu dia chin 2D vi tudng dja c h i t thay ddi hoac bj ddt gay chin Do n i y d i dUdc xd ly g i i 3D b i n g p h l n m I m cua Cdng ty khdng ed k i t hpp nghjch d i o dja chin b l n g tai l i l u dja SIMON HORtZONT thye h i l n d London VUdng qudc Anii chin 3D c h i t luong eao (Hlnh 11) n i n viee lien k i t trd n i n nam 1991 khd khan, eung l i ly tai khong ve daac b i n dd dinh v i d i y via tang sin pham Hon nda, t i i lieu dja v l t Thuc t l q u i trinh sCr dung, t l i lilu dja chin 2D ly gieng khoan chi t h i n gilng khoan d nhiJTng ehl dd de g i l i q u y l t d c v l n d l tim k i l m d c md Idn co khoing cd d c t i n g sin pham, khdng lien tue eho c i mat c l u trde dia c h i t ddn g i l n v i cic ddi tupng d l u ddd elt cfia c h i t khiln cho viec nghiin edu t o i n md khdng slu khPng IPn Tli l i l u d|a ehIn 2D khdng ly gili dUOc t h u i n Idi Mat khac tai Iliu sonic ehl daac h i i u chinh chfnh hien tupng g i l n g khoan sai dd slu hay g i l n g khoan kha xic d nhdng gilng khoan cd dja chin t h i n g ddng Ddi vPi md cd c l u true dja c h i t phdc tap, tai lilu dja chin gilng khoan VSP, edn da p h l n khdng ed hieu ehinh 2D khdng cho p h i p bo tri cie g i l n ed dinh nhdng gil^ Nhdng gilng khoan khd, khdng ddng dp slu thiet ke, khai thac ngap nuPc, khdng t i l p nhan nude bdm v i o , nhdng g i i n khai thie khdng ddng vi tri; chi cd sd it gilng ed s i n p h l m cao I I nhiJng van d l eIn dupc gilt quylt Do sd dung t i i lieu thu nd dja chan 3D edng nghe cu q u i n ly mo nen cdng t i c c l i t h i l n thu hdi d l u k i m h i l u q u i He thdng gian khai t h i c cd cic g i l n g khoan khai t h i c va bom ep khdng P vi tri tdi Uu khdng gian ba chieu Dieu ndi len tinh da dang, phdc tap cda md va la thach thdc cho edng t i e nghiin edu dja chat d i l u hanh khai thie md khoan t h i m djnh, khai t h i c v i bdm ep vj tri tdi UU.Gi£ khoan BH-4 khoan h i t ehilu s l u t h i l t k l khdng g i p ma t i l p tue khoan slu hon k h i tdi da va p h l i dCmg lat tnlj^ d i n b l m i t mdng Gieng khoan BH-9 v i mpt s d j ^ n khlc cung khdng khoan d i n mdng; h i l n tUpng chin S g i l n cd ^ n h da d i n h ehim d l x i y dung p h i i ddng H ^ j i cd hpi, nhijTng gilng khoan khdng dung vj tri t h i l t k l ^ mdt minh chdng NhiJ^g n i m cudi t h i p nien 80 cda t t ^ trude, Vietsovpetro da l l n ke ho?eh k h l o s i t dja chin | t r i n md Bach Hd nhUng khdng thUc hien dupe c h i cP k h i n i n g ky t h u l t Nam 1990, Vietsovpetro thyc Kraj i 16 U KHl-sd 4/2012 PETROVIETNAM khlo sit dja chin 3D l l n d l u t i l n d Viet Nam thPng qua khdng d i p dng dUpc vile n i n g eao chit lupng t i i lieu hpp dong vdi Cdng ty Dja v l t ly GECO Kit q u i khio sit cho cong t i e nghien edu ndt n l v l moi trudng bat d i n g chdng minh tfnh Uu v i l t cda edng n g h i mdi 3D, die biet huPng cho toan md, lam rd hlnh anh c l u trde dja ehat truPe d i y edn tranh cai va nhd dp ly g i l i nhdng nghi ngp v l vj tri eie gieng da khoan Tuy nhiin viie p h i duyet khio s i t dia chin 3D d md Bach Hd bj ehim t r i nhieu nguyin n h i n ehu quan, khach quan Den nam 1992, d i khai t h i c dUpe 10 trieu t i n d l u tho, dia ehIn 3D t r i n mpt khdi lupng khilm tdn 242km^ khdng phO h i t t o i n bd md Bach Hd mdi duoe phep thi edng Nim 2003, Vietsovpetro da thye h i l n thu nd dja chin 3D d p h l n d i i n tich cdn lai phia Ble md B^eh Hd thude khu vue hoat ddng cda Xi n g h i i p d l ndi vdi g i l n g khoan BH-10 n l m p h l n thu nd nam 1992 Cic nam 2007 - 2008, Vietsovpetro t i l p tuc t i l n h i n h k h i o sit dja chin 3D phan edn lai d phia Tiy - Bie noi t i l p g i i p vdi gieng khoan BH-11 v i p h l n Tiy - Nam md Bach Ho tiep gilp vdi md Rdng, cd gdi d l u vdi phan khao s i t n i m 1992 d khu vUc gieng BH-17 ndi d i d i t chan di giin eo djnh MSP-12 Nhung khdng ed ky thuat undershooting nen khdng thu daac h i t sd lieu d khu vUe Viec thu nd dia chan 3D bd sung theo cong n g h i cu Toln bp dien tieh khlo sat dja chan 3D P d c nam khic t r i n md Bach Ho khdng phd kin h i t d i l n tieh eIn t h i l t eda md (Hinh 2) M i c d u viy, nhdng thdng tin dja chin 3D cda phan cdn bd trdng truPc d i y d i I i m sing td t h i m bIy ehda d l u v i dupc khing djnh b l n g khoan siu Phuong p h i p tham dd dia chin cung d p nhilu thong tin dia chit v i die b i i t hlnh i n h cau trde dja chit m i eie phuong phap khic khong cP dupc Chinh vl viy m l tai lilu dia chin dupe sd dyng nhu l i t i i liiu co sd cung vdi cac t i l lieu gieng khoan khie q u i trinh tim kilm, tham dd va khai thac md PhUdng p h i p dia chin cd nhilu t l l n bd vupt bic v l ky thuat v i edng n g h i g i n lien vdi cic linh vpc khoa hoe ky t h u i t khac gidp cho edng t i c rim kilm, tham dd v i khai thie ning cao hieu q u i , rut n g i n thdi gian va gilm chi phi.Td phuong phap phln xa thdng thudng p h i t trien phUdng p h i p diem siu ehung lam tang ty sd sdng ed ieh t r i n sdng nhieu, die b i i t I i m suy g i i m sdng lap lai nhieu lan - mpt loai sdng nhieu die trung dia chin biln, sd mach dja chan cap thu tang dan td 12, 24,48 l l n d i n hang nghin maeh eho phep tang ning suit thu no, tang ngudn thdng tin v i t i n g dp phin g i i i tai lieu Ngudn no va c i p dia chin bien cung cd nhieu c l i t i l n chdng nhieu, tang cUdng dp tin hiiu thu Cung vdi ky t h u l t va edng n g h i dja chin, cdng t i c djnh vj ludn song hinh vPi khao sat dia chin eung cP nhieu t i l n bp Td djnh vi song vd tuyIn nhu SYLEDIS, ARGO den djnh vj v l tinh t o i n cau GPS dUpc d i chinh tin hliu Iim tang dp chinh xac djnh vj d i l m thu tuong dng vpi dp ehinh xie va dp phin giii eao cda d c ddi tUdng nghiin cdu Cong n g h i thu nd khdng ngdng phat trien nham khie phye nhdng han c h l truPc day khdng the thpc hiin dupc va tang dp chfnh xie eda tai lieu, lam giiu thdng tin dia ehat nhUghi sdng phan xa ehuyin ddi PS cd p h l n sdng ngang S vdi chi phi t h i p d l nghiin cdu nutne vatang dp sau nghiin cdu CPng nghe thu nd nhilu hudng hoic gde phUdng vj rpng cd g i i tri eao ddi vdi d c eau trde phdc tap v i cd dp bat dang hudng cao nhu mo Bach Ho Trong xd ly cung cd phln mem diet nhieu i p dyng rpng rii I i m tang chit lupng tai lilu nhu djeh ehuyin thPi gian 2D, djeh chuyen thc^ gian 3D, djeh ehuyen thPi gian hai l l n va mpt l l n sau cpng, dieh chuyin thPi gian truPc W2 Sa d6 cdc khu vUc khdo sdt dia chdn l5b dkhu vifc md Bgch Ho vd mo Rong epng, djeh chuyen sau sau v i truPc cong, dich chuyen bat dang hudng, xdly tap trung da d i l m Cac chuong trinh loe oiv mi : 17 m T H A M D O - KHAI THAC D A U KHI nhieu sPng lap lai nhilu l l n c l n t h i l t cho dja chin b i l n cung khdng ngdng p h i t t r i l n CPng n g h i xd ly t i p trung da d i l m khdng truyin thdng ed t i e dung n i n g cao ehIt luong t i i li§u die bi$t Sd maeh dja c h i n mpt elp thu: 240 Khoing elch gida t i m elc nhdm m i y thu: 12,5m;^ Khoing elch gida d e t u y l n d i l m gida chung CMP: 50m eho nhdng vung cd dja c h i t phdc tap v i ddi tUdng nghiin cdu d dp slu Idn m i dja chin thPng thuPng khPng g i l i Bpi phd: 60 quylt dupc Ngudn nd: ngudn dPn, sung hoi Cho d i n nay, da khai thie dUoe g i n 200 t r i l u t i n d l u thP m i t l i li|u dia chin 3D thu nd theo cdng n g h | cda nhCmg n i m trudc v i n edn dang sd dung d l p h i t t r i l n va khai thic md Bach Hd Chinh d i l u niy d i n d i n nhdng khd khin q u i trlnh t h i m va khai thic T i i l i l u dia c h i n 3D n i m 1992 Khoing eieh giijfa hai d i l m nd: 25m Thu nd theo hudng Ddng Nam - Tly B i c Djnh vi: SYLEDIS v i GPS Cdng t i c thu nd dupe t i l n h i n h tinh trang m6 cd nhilu chUdng ng^i v l t nhU elc g i i n MSP, BK, eie tlu chda d l u , d c t l u xly dyng, djch vy, hi thdng d c dudng N i m 1992, Cdng ty GECO da huy dpng t i u dja chin thu no GECO KAPPA v i t i u nd RED GOLD d l thUc h i | n k h i o sit dta chin 3D t r i n md Bach Hd theo hpp ddng ky k i t vPi Vietsovpetro ThPng sd thu nd cd b i n nhu sau: dng d i n d l u n g l m v i e l p d i | n n g l m 04 khlc phuc rinh tr^ng n l y cung nhu b l o d i m an t o l n eie edng trlnh b l l n v l thu d l y du thdng tin dja chin, Cdng ty GECO da i p dyng thu nd hai t i u v i theo ky t h u l t undershooting H^ thdng djnh vj SYLEDIS l l m v i ^ khdng dn djnh,dl Dien tich k h l o sit 3D dd bdi: 242 km^ bj I n h hudng bdi thPi t i l t v l v i o ban d i m , cP t i m vdi han Sd d p thu: ehl, dp ehinh xie khdng cao Tai thdi d i l m nly HI tfidng Dp d i i mdi c i p thu: 3.000m dung l l m h i thdng t h d elp k h i o sit dja v i t ly dd djnh vj vi tinh t o l n e l u GPS eua My chua hoin ehinh chl chinh xle khdng cao v i chda dUpc Chinh phd My cho p h i p sddung d i n sy H I thdng la ban dat dpe theo elp thu, h | thdng siiu I m v i quang hpe (LASER) d dlu, cudi d p v l ngudn nd, h i thdng RGPS d i t d phao cudi cip thu de djnh vi vj tri ngudn nd v l d i l m thu T i i li^u thuc dja 3D n i y dupc xd ly djch ehuyin thi6 gian sau cPng d trung t i m xCr ly n h l t h I u GECO tai Kuala Lumper (Malaysia) dudi su g i l m s i t cua d c ehuyin gia Vietsovpetro v l Tdng cdng ty D l u Vilt Nam Til lieu n l y khdng d i m b l o c h i t lupng de nghiin cdu chl tilt (Hinh 4) Vile xCf ly l^i t l i l i l u dja c h i n 3D niy trdthinh mpt yeu c l u d l nghiin cdu dja c h i t md Vln de nSy khdng d l d i n g dupe c h i p n h i n cd nhilu y ki^n khie Do nhu c l u nghiin cdu md, Wetsovpetro d i thyc h i ^ xd ly lai t i i lieu dja chin thu nd n l m 1992 b i n g djch chuyen chieu slu sau edng t i p trung v i o t i n g mdng v i o nlm 1995 d Trung t i m xd ly n h i t h I u phu GOLDEN GEOPHYSICAL tai Texas (Hoa Ky) de phuc vu cho cdng t i c md phdng eua n h i t h I u chinh SSI, dudi sy g i l m s i t chit che cda d?i d i l n Vietsovpetro, sau dd d i t i l n h i n h xd ly djch ehuyfii Hinh Mat cdtdia chdn 2D [9] \ 18 OAll KHl-so 4/2012 chilu slu trude cpng PrSDM Cdng n g h i mdi xd ly 6% PETROVIETNAM chuyen chieu slu eho k i t q u i tdt d i n h d l u cot mde quan trpng nghiin edu md Bgch Hd (Hinh 5) Ket q u i xCf ly lai t l i li^u dja chin 3D b l n g djch chuyen chilu slu md hudng di mdi cho nhdng n h i nghien cdu t i n g chda mong granite ndt n l md Bach Hd Til lieu n i y eung elp d c thdng tin dja c h i t mdi b l n g hlnh i n h elu true rd r i n g v i ly g i l l dupe h i l n tupng eie gilng khoan khd hay khoan khdng dung ehilu slu t h i l t k l v i lam thay ddi quan niem v l tU dja chit, binh dd elu tao be mat t i n g mdng thay doi chi t i l t d i n g k l (Hinh 6,7,8,9) Nhufng khIi niem v i thuat ngijf'ting khdng p h l n dj°,"tlng phong hda", "mong tuoi" dupc nhin n h i n d l y dd hon Van d l ddt gay nghjch g l y tranh d i t r i n cic t l i lieu trUPc d i y cung dupe I i m sing td (Hlnh 5) Td day, viec khai t h i c thong tin dja chin mPng md Bach Hd de khlng djnh cd sutdn tai t i n g ehda mdng d i dUde trien khai m i trudc d l y khdng dupe d l cap d i n Ngoai trd trudng hpp b i o d o cua Vien Dlu Vilt Nam m i t i c g i i l i TSKH TrUdng Minh va KS Ha Qudc Quin d i manh dan sd dung thPng tin dja chan 2D dUdi mdng d l d i n h g i i trQ lupng mpt eieh lac quan, dUa trd lupng t i l m nang d l u eda md l l n d i n ty t i n nhung khdng dupe chd y den Tuyln dja chin n g l n v i c h i l u d i i c i p ehua du dai, khdng phu hdp vdi chieu siu nghiin cdu, ban che thu sdng trao ddi PS d i n d i n han e h l thu n h i n thdng tin b i t d i n g hudng cho ddi tupng d l u d cic dd s i u khic nhau, d i e b i l t l i mdng ndt n l Mac du dp d l i ghi I I Ssec, nhung t d d d slu t i n g ehda mdng ndt n l trd xudng tdn tai sdng dpe P v i y i u d i n t r i n n i n phdng nhieu, sdng chuyin ddi PS de nghiin edu ndt n l khdng thu dupc d l y du Khoing cich gida d c truyen CMP thda khdng cd k h i nang tang dd p h i n giii cao hem Thu nd theo mdt hudng DPng Nam - Tly Bic v i ngupc lai, chl l i 2D dan diy, dp phin gili t h i p v l nhilu manh, khPng eho hinh i n h elu trdc holn thiln Bpi phd 60 khPng dd Idn di loai trd sdng lap lai Dp chfnh xic v i dn djnh eua he thdng djnh vj bj han ehl Xd ly ehUa ed eie edng n g h i nhU ngiy Vt viy, tai lieu dia chin 3D thu nhan theo edng n g h i eu trudc day khPng phln anh dupc mdi quan h i biin dp va thPng tin b i t d i n g huPng cda t i n g chda Sddung sdng dpe P khPng phan b i i t dupc d c ly g l y dj thuPng Viec p h i t hien d l u mong l i may m i n v i r l t tinh cd NhCfng gieng khoan tham dd trudc d i y n h l t h I u khoan thiet ke, thi cdng x i y dUng gilng khoan, thd via v i v i l t b i o d o tdng ket khoan (trong t h i l t k l gieng khoan deu cd yeu d u khoan xuyIn vao mdng du siu, l l y m l u di chuTng minh d i dt qua h i t l i t d t tram tich) Mat khic, n h i thau thudng t h i l t k l v l khoan siu hon mdng, Vi vly, gieng khoan BH-1 khoan vao mdng phli d i ^ g lai theo chilu siu thiet ke, mac du cd bleu h i i n m i t dung djch va tdc dp khoan nhanh eon co k h i n i n g khoan siu hdn Khi g i l n g khoan Bgch Hd BH-6 khoan mdng slu hdn t h i l t ke thay d l u cung khdng dupc xie nhin m i cho r i n g d l u thu dUdc tCrtlng Oiigocen Chi sau t l i lieu ^ a chin 3D djch ehuyen chilu slu cd ehat lupng tdt v l ket q u i nghien cdu d c m l u Idi, mau bien dp, sPng ngang S hay sdng chuyen ddi PS cd t i c dung tdt cho viec nghien cdu Tii lieu dja chin khong cd sdng ngang S hay sdng chuyen ddi PS trd nen khdng nhay d m va khdng thich hpp cho viec i p dung d c ky thuat va cdng nghe mdi de nghiin edu ndt n l , b i t dang hudng, Viec minh giii, phan tich v i nghien edu nhu nghjch d i o dja chan n h l m nhin biet ranh gidi eac t i n g sin pham, sU thay ddi tudng (Hinh 11), bien dp thay ddi theo khoing d c h thu nd AVO, trd khang I m hpc Al, trd khang dan hdi EL he sd Poission, tinh c h i t t i n g ehda c l n eP tai lieu dia chin 3D c h i t lupng cao Mdt sd cdng trinh nghiin edu d i sddung t i i lieu dja chin 3D thdng thudng han c h l ve chat lUdng lam d l u v i o cho d c ky t h u l t cdng nghe nhu nghjch d i o ^ a chin, AVO khdng co k i t q u i t d t dau d c gieng khlc mdi cd dd cd sd ket luan chinh xac ve dong d l u mdng ndt n l dUpc phat h i l n d l u t i l n Ly phdi thUc hien thu nd 3D va x£r ly t l i Il4u blng d md Bach Hd chinh tai g i l n g khoan BH-6 cong n g h ^ cao NhOng han c h l mang tinh Ijeh si^cda lan thu nd dia chin 3D d l u tien nam 1992II: Hinh I n h dia chin chinh xie cao mang tinh quylt dinh den k h i nang cdng cua viec xac djnh vi tri Di|n tieh mang lUdi 3D nhd khdng phu trum het gilng khoan va v| tri gian khai thie MSP pham t o l n bd dien tfeh md, edn bd trdng nhdng d i l n tich khdng vi md Dua t r i n ky t h u l t va cdng nghe dja chin truyen ed thdng tin thdng, nhOfng hinh i n h dja chan thUdng dya tren nhdng BlSlI Slltf s o 4/2012 19 THAM DO - KHAI THAC D A U KHI gia djnh sai v l d u true dja chit dudi siu Nghien cdu md qii.i liiynhii'n,c()n{)l,i( thu no dia chan 3D nam 1992 van ed eau true phdc tap dd cd ting chda da mdng ndt Ol MIHIIKI h i n d i c v e tuduy va cong nghe Oay chinh li|j| n l nhu md Bach Hd ddi hdi mpt elch tilp cin ky thu$t d'Mir (11 hirii |)h£ ; ^ S K ,>v ' / ^ ^ ' N^^^^' 4^^v-.^, , \ : ' 'A Hlnh Mo ivnh ,1iini-i,iiI liunq lien I i) i d nil lii-u dm ,1 I'll \(ii ln-ii llm vat lyiiicin} hlhfoP'SDM.iolicunni Tiinh \thin Cudng> 19! i Ini kiiai Hinh Ban cau true be mdt tdng mong dua tren tdi lieu da ciicin 3D xil iy theo PrSD/v) I9j ddi tuong khai thac dau Iai P dp sau Ion hon day cac gienc da khoan va trai rdng hon dutinh ban dau.Tang mongnd ne la moi trUPng bat d i n g hudng die trung truyen s6n< dja chan ngang S va song chuyen ddi PS ma den naychiii ap dung ky thuat cong nghe phii hop, Khai thac cac thPni tin ve mat dp nut ne, hudng nut ne va phan bo nut ne dc hdi phai CO thong tin ve song ngang Shay song trao doi Pi Huong nin ne co the duoc suy luan td viec phdn tich to Hinh Bdn cdu true bi mat tdng mdng dpa trin tdi liiu dia chdn 2D thdng thuPng [9] c6 cdc gdc phuang vi khde Cho nin thu nS dftm Ky thuat khlo sit dja chan 3D tren md Bach Hd truPc 3D nhiiu gdc phuang vi Id mdt tmng nhOng vdn dlcrfril? d i y d n daac thay the blng nhdng ePng nghe ky t h u l t fdm d^ed khd ndng thu thdp nhiiu thdng tin viniytnl hien dai hdn Sd lieu dja chan eu trd nen khdng cdn phd Do sdng ngang S khPng lan truyin i hpp, thPng tin dja chit d c gilng khoan khdng du de liln b i l n n i n sCf dung m i y thu geophones khd thi c d n g l ,| k i t neu khdng ed sd lilu dia chin gilu thdng tin v l dp t h i n h eao, thay v i o dd vile thu sdng trao ddi PS b l n ^ chfnh xlc eao l l m co sd Mang ludi dja chin 3D trudc d l y dung elp thu dja c h i n ndi thdng thudng chda miy ti* chi phu tren mpt pham vi han hep tren phan dinh md ma hydrophones {Hinh 13) ed khoing d c h thu nd (offeef|t i 22 nlBud-: PETROVIETNAM KhoSng c^ch thu n6 theo nhilu gde phuong vi khie hay gdc phuong vj rdng se g i l m d i n g ke chi phf thu nd va xd ly Ap dung cdng n g h i thu nd mdi cd khoing d c h may thu - ngudn nd Idn v l gdc phuong vj rPng hay nhieu gPc phuong vj d l thu tin hilu sdng trao ddi PS ehda cac thdng tin v l hudng, m|t dd v i cuPng dp ndt n l II b i l n phap ky t h u i t ddng v l can t h i l t d l nghiin cdu t i n g chda mdng Cdng n g h i mdi hiln cho phip thyc hiln 3D hoan t h i l n v i dung nghTa cda nd thay the dja chin 3D don g i l n trudc dly Vile thu nd d c hudng khac Hinh 10 Sil khde biit phu thudc vdo lihodng cdch thu no vd thdi gioh phdn xg giao dudng cong bdt ddng hudng Anisotropy (dd} vdhoac gdc phuong v| rdng se cho hinh I n h c l u true d l y du, nhilu thPng tin (Hlnh 12), dP cP thdng tin b i t dudng cong ding hudng isotropy (xonh) d i n g huPng Thuit ngd"gPc phuong vj rPng hay nhilu -W'jtn gdc phuong vj"trd n i n sPi dpng hoat ddng dja v i t ly tren t h i gidi nhufng nam g i n day D i y l i ePng nghe mdi dupc p h i t trien nhP djnh vi cP dp ehinh xie wtiim ™W*IH)||I WHH, !"*^LDIJ||II,IJW^,„ ' I iiw w >m>iwiii ^ n i — ^ ' — ' '*^»lN|i cao v i t i n h ddng bp cao gida cic tau thu nd dia chin.Thi edng thu no dja chan 3D tren mP dang khai thac la cong vile khdng may de ding, doi hdi td chdc tdt va k i t hpp ddng bp gida cac hoat dpng tren md Dja chan 3D cdng n g h i cao c i ve thu nd v i xd ly cho phep tang thong tin va k h i nang loai trd song lap lat cao lam t i n g ehat lUdng Hinh 11 Mat cat dia chdn {trai} vd mdt cdt nghich dao dja chan hinh anh be mat ranh giPi p h i n xa tdt hon, t i n g phan phai) [7] Day la sU chuyen doi td mdt cdt dia chan sang mdt catgiai, die biet d khu vyc xung quanh ddt g i y va t i n g dia char de nghien cUu tudng dia char, hinh dang via sdn phdm ti'nh liln tuc true ddng pha, ket qua nghiin cdu se cd chfnh xie cao Chat lupng tai liiu dja chan quylt djnh den chit lupng k i t q u i cae phUdng p h i p ky thuat nghien cdu dja chat nhu nghjch d i o cfia chin inversion (Hinh 11), bien dp thay ddi theo khoang cich AVO hay gde phuong vj AVAZ anh huPng d i n nghiin edu die tfnh tang chda nhu dp rdng, dp tham, dp bao hoa, b i n dd tang chda, b i n dd phln bd ndt ne, d l u Cho den van chua ve dupe b i n dd tin cay be mat va day t i n g sin pham hoac ehilu d i y tang san pham D i l u n l y t h i hiin ehfnh xac trd lupng vi d i i n tich v i t h i tich II hai sd eie thdng sd tinh trd lupng I n h hudng manh den ket q u i tinh toan Mpt eon sd trd lUdng cd sai sd Idn se anh hudng d i n viie xay dyng va thyc hiln d e ke hoaeh t i l p theo Blng cdng nghe mdi cP the xac djnh daac t h i m cie ddi tupng cPn an chda, eli t h i i n duoe h i sd thu hdi dau, g i l m bdt d i n g ke phan d l u bd sdt, tim d c vj tri mPi thfch hdp cho d c gilng khoan hoac gian khai thie mdt Hmh 12 So sdnh mat cdt dja chdn 3D thong thudng (tren) vdi mat ke hoach t l i p h i t trien md, lam tang them he sd khai thac va tang hieu qua tham dP khai thac cdt dia chdn gdcphuong virgng (dudi) [12] lUWIS s o 4/2012 23 I T H A M D O - KHAI THAC D A U KHi Dia c h i n 3D nhteu gPe phUdng vj hay gdc phUong vj rpng ed dp d l i d p thu Idn v i cie t u y l n d i l m s l u chung dd d i i hpp ly, cP di^n tfeh thu nd dd rpng phd kin t o i n bp dien tieh md se cung d p d l y dd thdng tin c h i t luong eao c l n t h i l t d l n g h i i n cdu md VI v|y, vi$e thu nd lai dja c h i n 3D t r i n md B^ich Hd v l xd ly b l n g edng n g h i eao cho mdi trudng b i t d i n g hUPng eda t i n g ehda mdng granite ndt n l se l i bUde t i l n quan trpng n g h i i n cdu md d l g i l i q u y l t nhdng khd k h i n v i y i u c l u sin xult, Nhdng y i u td di t i n g c h i t luong t i i li|u dia chin thu nd lai l i : Hinh 13 Minli IKIII •.ildiing liai tau tini no de lang khoang cdch th ninih