Tuygn tap bao cao Hoi nghj KHCN"30 nam DJu khi Viet Nam Co'''' hoi mdi, thach thuc mdi" 251 DANH GIA LAI D A C TRUING CHLTA DAU KHI LAT cAx DIA C H A T • • • MOT SO GIENG KHOAN 6 MIEN VONG H A N Q I VA N[.]
Tuygn tap bao cao Hoi nghj KHCN"30 nam DJu Viet Nam: Co' hoi mdi, thach thuc mdi" 251 DANH GIA LAI D A C TRUING CHLTA D A U KHI LAT cAx DIA C H A T • • • MOT SO GIENG KHOAN MIEN VONG H A N Q I V A NHLTNG KET QUA NGHIEN c t r u M6I O C A U TAO KIEN XU^OTVG A Doan Tham Cdng ty Ddu tw vd Phdt triin Ddu TOM TAT Mien vong Hd Ndi da qua hon 40 ndm tim kiim ddu khi, vi thi da cd mdt lugng l&n tdt lieu dia chdt - dia vdt ly Nhdm tim kiim ddu bd sung cho md Tiin Hdi "C" dang & th&i ky egn kiet, nhiem vu cdp thiit ddt cho cdc nhd chuyen mdn la kit hgp v&i tdi lieu m&i cua cdc nhd thdu, minh gidi ddnh gid lgi todn bd tdi lieu dia chdt - dia vdt ly th&i ky tru&c ndm 1984 nhdm ldm sdng td khd ndng chua cua lat cdt dia chdt & nhung cdu tgo tru&c day dd khoan Di minh gidi lgi todn bd tdi lieu tru&c day, ciing v&i cdc tdi Hiu dia chdt, dia vdt ly tren mat, tdi lieu dia vgt ly giing khoan(DVLGK) la dgng tdi lieu phong phu vd ddy du nhdt Td hgp cdc phuang phdp DVLGK su dung th&i ky ndy Id cua Liin Xd cu Phuong phdp minh gidl su dimg tru&c day cung la cdc phuong phdp mang tinh truyin thdng O th&i diim hiin tgi, niu sir dung phuong phdp phdn tich tru&c day se gap phdi khd khdn tdi lieu khdng ddng bd, cdc tham sd dung dich khoan thiiu, v.v Vi vdy, viec tim phuong phdp minh gidi tdi lieu phu hgp v&i bd tdi lieu cu Id hit sue quan Mat khdc, td hgp cdc phuong phdp DVLGK & th&l ky ndy nhin chung cdn nhiiu hgn chi, tdi lieu thu duge phdi qua nhiiu hiiu ehinh vd ddc biet nhung sai sd gap phdi thu&ng mang tinh hi thdng Bdi viit ndy trinh bdy tdm tdt td hgp cdc phuong phdp DVLGK vd phuang phdp ddnh gid lgi khd ndng chua ddu phii hgp v&i diiu kiin hiin tgi nhdm logi bd nhung khd khdn vd sai sd ndi trin Phdn tiip theo la mdt sd kit qud minh gidi nhgn dugc & mot sd giing khogn, ddc biet Id da phdt hiin duge dogn lat cdt ehira khi, thudc diep Phu Cu & giing khoan 101 tren cdu tgo Kiin Xuong A vd mdt sd y kiin trao ddi nhdm ldm sdng td khd ndng chira ddu cua cdu tgo ndy TO HOP c A C PHUONG PHAP NGHIEN ClTU DVLGK D A DU^OC TIEN H A N H CAC GIENG KHOAN MIEN VONG H A NOI TRl/OC N A M 1984 Cac phuoTig phap phong xa - Phong xa ty nhien GK - Ph6ng xa Natron: NGR 252 Panh gia lai dac trung chua dhu lat cSt dja chSt mot s6 gigng khoan d mien vongJjaJVOj_vg_^i:^ Cac phuffng phap dien va dan dien - Dien truong ty nhien: SP - Dien tro: BKZ (6 mgt s l giing), BK, MKZ, MBK - Cam img IK Cac phuong phap sieu am - Sieu am r6ng AK - Sieu am danh gia chat lugng xi mang AKC Cac phuffng phap trang thai ky thuat gieng khoan - Duong kinh (K) - Do lech gieng khoan - Nhiet (T) Tai lieu DVLGK thu dugc a cac gieng khoan MVHN bao g6m mgt t6 hgp nhieu phuong phap kbac Trong thai ky dau ciia thap nien 1990, c6ng nghe DVLGK cua Lien X6 moi chi dat toi ky thuat ghi tuong ty va nguyen ly cac phuong phap ciing chi la cac phuong phap truyen th6ng nhu dien tro BKZ, phong xa mgt ngu6n thu, cac phuong phap thuong cho cac duong cong dam bao chat lugng thiet bi da hoan thien song chi s6 cac duong cong thuong bj anh buong boi chieu day eiia via va dien tro via bao quanh hoae bi anh buong boi m6i truong gieng khoan (duong kinh, vo biin, V.V.) De loai trir nhtrng anh huong tren cac phuong phap nghien ciru dac biet da dugc sir dyng nhu dien tro huong dong BK, MBK, cam img IK va sieu am Nhung nhiing phuong phap dang thoi ky thir nghiem, cac duong cong thu thap dugc thuong kem chit lugng thiet bj lam viec chua 6n djnh nen viec sir dyng chiing de minh giai djnh lugng bj ban che Vi vay, viec phan tich djnh lugng dl xac djnh cac th6ng s l ciia via chiia chii yeu sir dyng cac phuong phap truyen th6ng Tai lieu DVLGK dugc sir dyng de phan tieh day nhin chung la dam bao chit lugng, dac biet tai lieu karota truyin thing (BKZ, PS, K, GK, AKC) Con cac tai lieu kbac nhu BK, phong xa Natron (NGK) dugc sir dyng timg phin phy thuge vao chit lugng cua timg dgt dilu kien trang thai ky thuat giing khoan tit phii hgp voi m6i truong lam viec eiia thiet bj Cac duong cong IK, AK kh6ng dam bao chit lugng dk phan tich djnh lugng nen kh6ng dugc sir dyng CAC PHl/ONG P H A P NGHIEN ClTU DAC TINH CHlTA D A U KHI CUA L A T CAT DIA C H A T GIENG KHOAN PhuoTig phap xac djnh bao hoa nuffc cua da chu-a Mgt nhtrng th6ng s6 quan trgng viec danh gia lai dac tinh chiia eua lat cat la bao hoa nuoc duoc tinh toan tir c6ng thirc; '' a.R ^- Tuygn tap bao eao Hoi nghj KHCN"30 nam Phu Viet Nam: Co' hoi mdi, thach thuc mdi" 253 Trong do: Do bao hoa nuoc O: Rt: Rvv^ a: m: n: Do r6ng da chira Dien tro suat via chua Dien tro suat nuoc via Th6ng so thach hgc He so ximang He s6 bao hoa Nhu vay, de xac djnh S^ cin bilt chinh xac gia trj tren, dilu la kho tim dugc bg tai lieu karota truoc day Mat khae, dii voi t l hgp karota ciia Lien X6 cu thi he phuong phap BKZ g6m zond la phi biin va co tin tuong nhit (AO = 0,45m, 1,05m, 2,25m, 4,25m, 8,5m) Vi vay, gia trj dien tro thu dugc tir cac zond BKZ da dugc sir dyng de xac djnh nhim loai trir cac kho khan va sai s l mang tinh he thing noi tren xuit phat tucac c6ng thirc sau: • Cdng thiire Archie: R= a.R, "CL ^m_gn Trong do: Rci: Dien tro? chit luu Diin tro vung gdn: a.R, Trong RF Sxo (1) O^^.S" Dien tra chat tham dung dich Do bao hoa nuoc du He so bao hoa n: Dien tro via nghiin eiru: RT — Tir (1) va (2), voi n == xac djnh Sw a.R w m_sn w (2) w R., ^M R W ^0.5 Voi via chira nuoc (R-pnc, R^inc): S R Tnc R Mnc Voi via chira dau khi: R R, 0.5 R R Tnc R R Do bao boa s,„ viing gin, tuong iing voi zond AO = 0,45m, da dugc danh gia cac bao cao truac day co gia tri tir 0,80 - 0,85 doRK, 'M R Tnc R, R Mnc 0.85 J (3) 254 Panh gia lai dac trung chua dau lat c§t dja chat mot so gieng khoan d mign vong Ha_N9ilJ_iLi day RT liy gia trj dien tro cac zond co AO = 2,25m; 4,25m va 8,5m Bing each tinh bao boa nuoc theo phuong phap tren cac tham s l kbac kh6ng tham gia vao bilu thiic (3) ma chi co cac gia trj dien tro ciia cac zond voi cac chieu sau nghien cim khae cimg mgt lan Day la uu diem cua phuang phap tinh S^ truong hgp sir dyng t6 hgp karota cua Lien X6 cii Phuffng phap danh gia dac tinh chira nhff "hieu rnig HC" tren tl hop cac du-6-ng cong BKZ cac thoi gian khae Phuong phap dya vao sy thay d6i ban kinh dai tham dung dich theo thoi gian Trong cac zond BKZ chilu sau nghien cuu ciia m6i zond phy thuoc kich thuoc zond: - Zond A 0.4 M 0.1 N c6 chilu sau nghien cuu D = 0,45m - Zond A M 0.5 N CO chilu sau nghien cim D = 2,25m - Zond A 4M 0.5 N co chilu sau nghien cuu D = 4,25m - Zond A 8M N co chieu sau nghien cim D = 8,5m Dii voi via chiia diu khi, nlu co to hgp BKZ lap cac thoi diem kbac thi cac chi so dien tro ciia zond (dang duong cong) co D nho se giam dan theo thai gian, liic zond co D Ion duong cong se kh6ng d6i So sanh cac t6 hgp lap tren se phat hien dugc "hieu ung HC" Tir danh gia djnh tinh dugc dac trung chira ciia via KET QUA MINH GlAl T A I LIEU Phan tich lai tap trung lat cat diep Phu Cir voi gan 20 gieng khoan a dai cau tao Tien Hai va Kien Xuong cho ket qua sau day: • Ddi cdu tgo Tiin Hdi: Da khang djnh lai cac tap cat chiia cu6i Phii Cir II gap a tren dirt gay co gieng khoan va gieng khoan duoi diit gay VTnh Ninh thuge phan D6ng Nam cau tao Tien Hai C, cau tao Tien Hai A lat cat deu chiia nuoc • Tgi cdu tgo Kiin Xuong A da khoan gieng 101, ket qua phan tich lai a Bang cho thay gieng khoan gap mgt s6 tap cat chiia dau Tap cat kit culi Phii Cir II g6m tap vai chieu day t6ng cgng la 44m, co rong trung binh la 14% va bao hoa nuac tir 47 - 59% Phin lat cit Phii Cir I gap tap vai ting chilu day la 47,6m, co ring tir 11 - 13% va bao hoa nuoc la 49 - 56% Kit qua chi s l TG (Hinh 1) ciia tram karota ciing da chi ham lugng t6ng a tram va lay mau dung dich phan tich tang dang ke bat dau tir phin gin day Phii Cir den phan lat cat Phong Chau Chi s6 TG tram tang tir 0,1% din 2,5 - 3% TG tach tir mau dung dich tang len den - 11% Ket qua thir via cho thiy cac tap via truac day deu nhan dugc lugng nuoc kh6ng dang kl, dilu co thi kh6ng phan anh diing ban chat via Do vay gieng khoan va eiu tao Kiln Xuong A cin tap trung nghien cim toan dien hon thai gian toi Mat khae kit qua minh giai DVLGK cua gieng 101 cung cin lam sang to mgt s l vin dl ma hien chua co dilu kien giai quyet Dac biet phan lat cit Phil Cir I, co chi s l TG cao nhung dang cac duong cong BKZ lin khae kh6ng bilu hien ro rang "hieu img HC" (xem cac Hinh 1-3) Tuygn tap bao cao Hoi nghj KHCN"30 nam Dau Viet Nam: Co' hoi moi, thach thuc mdi" A'^rf/J iAt rij^ Aim /t-ftyjUi AJttM /.fr /Aye 255 Cirinjifyrt ^f^ (Y.J -^-ôwf M ããf^igiil Hinh 1: Bieu Karota gieng khoan 101 256 Oanh gia lai dac trung chua dau lat cat dja chat mot s6 gieng khoan d mien v6ngJjj_N£l-^.^-^^ HINH IIA VIA; - CHUA NUOC DOTI (17-4-74) DO SAU (10 NGAY) 20 40 DOT II (1-6-74) DO SAU 2.5 T 60 40 20 ohmm DOT III (15-8-74) DO SAU 4.5 T 40 eo ohmm ohmm HINH II B VIA; • CHUA DAU KHI DOT III (14-8-74) DOSAU T DOT II (1-6-74) DOSAU2T DOTI (17-4-74) DO SAU NGAY 80 ohmm 20 40 60 80 ohmm 20 40 60 -228( VIA: (6-7-6) H 1= 21.6 m PHi;= 13% Sw =0.44-0.48 -2300 Hinh 2: D§c di^m phan b6 dirfmg cong di?n trff BKZ via v^ via 80 ohmm Tuygn tap bao cao Hoi nghj KHCN"30 nam Phu Viet Nam: Co' hoi mdi, thach thuc mdi" D A C DIEM P H A N BO D U O N G C O N G B K Z CK -'J- DC'T DO I h - Cl 74i DO SAU - r 20 43 50 CAU TAO KIEN A U D N G A DOT DO III i ' / ' i DO SAU i.5 T ohnr-! 20 43 50 30 onr / \ •2480 \ VIA ' '4 IVIACOti/-~-CDIEMCHI KHONG RC RANG I / ? Hinh 3: Cac diem phan bo duong cong BKZ via : 13-14 CK • 0DOT DO I I I - Q ,'41 DO SAU 20 2640 40 CAU TAO KIEN XUONG A " S NQ.AY 00 onriri DGI D O Ill I'6 741 0,0 SAU T 20 40 GO "jO ohn- *'*^^^ VIA 20 IVIA NUO;: GMUANi V "^^ ^•x Hinh 4: Dac diem phan bo duong cong BKZ via 20 "chua nuoc' 257 258 Danh gia lai dac trung chua d^u lat cSt dja chSt mot s6 gigng khoan d mien v6ngj4aJN9J_l^_^i: TRAO D I V E K E T QUA M I DANH GIA LAI KHA NANG CHIJA HC VA KET QUA THlT VIA GIENG KHOAN 101 TREN CAU TAO K I E N XU^ONG A Nhu tren da noi ket qua thu via cac tap da chua a giing khoan 101 co the khong phan anh dung ban ch4t via, ma thuc te day la lat cat chua HC Dk lam sang to van de c^n xac dinh dugc ban kinh doi tham dung dich vao cac via chua qua phan tich cac t6 hgp duong cong BKZ cac dgt karota va ket qua tinh bao boa nuac doi voi zond CO ban kinh nghien cuu kbac day my via s6 (2277,6 - 2289,2m), dugc bi§u diln tren Hinh va Bang 1, dl phan tich kha nang chua HC va nghien cuu ban kinh doi tham cua via so voi via chua nuoc so va 20 - Ddi voi via chua nuac so (Hinh 2a) va via 20 (Hinh 4) cac dgt each khoang 2,5 thang nhung phan bo cac duang cong BKZ kbac khong dang kk - D6i vai via s6 chua HC (Hinh 2b) su phan bo cua duang cong sau cac khoang thoi gian ma via kbac (dgt I - sau ngay, dgt II - sau thang, dgt III - sau thang) la hoan toan khae Hai duang cong AO = 2,25m va 4,25m tu cho nam ben phai duang cong AO = 8,5m dgt I va II, den dgt III da chuyen sang ben trai duang chat tham dung dich lam giam dien tro va day lui HC vao sau so vai gieng khoan Hien tugng dugc ggi la "hieu ung HC" va chung minh ro rang via nghien QUU chiia dau va ban kinh tham dung dich sau thang ma via da vugt qua 4m Ket hgp vai ket qua xac dinh bao boa nuac doi vai cac zond co ban kinh nghien cuu tCr nong den sau thay rang, bao boa nuac co cac gia tri giam theo chieu sau nghien cuu (Bang 1): Swa(AO = 2.25) "^ 0,67 > Svva(AO = 4.25) = 0,58 > Swa(AO = 8.5) ^ 0^47 Dieu mgt lan niJa khang dinh via la via chua dau va ban kinh thim rat sau da vugt qua 4m (co the tai 8m) ke tu giing khoan Ket qua thu via so tai chilu sau 2276 - 2284m phhn noc via, thu dugc nuac vai luu lugng 0,003mVng.d./atm Vai ban kinh dai th4m lan ban 4m va dan bSn ma via loai PK-103D, xuyen sau cua no vao via tu 0,25 - 0,7m cho th4y viec nghien cuu via mai chi dung lai a phan ngoai cua dai thhm nen lugng nuac chi la lugng chat tham dung dich ngam vao via day ciing chn phai quan tam tai phan thach hgc cua via, nhiJng via chua thuge diep Phu Cu thuang co set tu trung binh tra len, kha nang tham kem Do do, co nuac tham dung dich vao via, set se truang no, tham se giam Doi vai via s6 6, dugc danh gia la via chua dhu t6t nhat lat cat, dung dich th4m vao sau ban 4m va giu via vai thai gian ban thang (khong chong 6ng, tram ximang) thi viec khong co dong HC tu via thu la dieu hien nhien de xay Do la ly via chua HC nhung thu via khong cho kit qua mong muon 259 Tuygn tap b^o cao HQi nghj KHCN"30 nam Phu Viet Nam: Co' hoi mdi, thach thiic mdi" Bang 1: Kit qua minh giai DVLGK GK 101 (dot HI: 18/8/1974) H STT R2 Rj RH -e- Cau tao Kien Xvtffng A 5„.,„ S„.u S U Chieu sdu (m) Strain 5„„,« S„„ll 112) 1901,6 _ 1911,6 10,0 6,6 24 22 16 14,40 0,52 0,55 0,64 1,00 0,94 1,00 2001,6 - 2009,6 8,0 7,4 28,5 20 18 13,80 0,51 0,61 0,64 1,00 1,00 1,00 2060,0 - 2068,0 8,0 6,4 28 20 18 14,60 0,48 0,57 0,60 0,94 0,97 0,93 2087,6 - 2095,6 8,0 7,2 27 20 15,5 14,00 0,52 0,60 0,68 1,00 1,00 1,00 2227,2 - 2236,0 8,8 7,2 37 32 43 14,00 0,44 0,47 0,41 0,74 0,69 0,54 2277,6 - 2299,2 21,6 8,3 51,5 51,8 65,2 13,00 0,40 0,40 0,36 0,67 0,58 0,47 2324,0 - 2337,6 13,6 8,7 55,4 54,3 46,9 12,40 0,40 0,40 0,43 0,66 0.58 0,57 KET LUAN Tu ket qua minh giai tai lieu va nhung van de trao doi a tren co the tin rang, lat cat dia chat ma tai gieng khoan 101 da gap nhiing tap cat ket chua dau diep Phu Cu vai tong chieu day chua it nhat ciang khoang 35m a cac tap cat cuoi Phu Cu II va co the dat tai tren 60m (?), neu dac tinh chua dau cua cac tap cat diep Phia Cir I dugc khang dinh co them cac thong tin bo sung kbac Vi vay, viec quay lai nghien cuu cau tao Kien Xuang A nen som dugc thuc hien va hy vgng a tinh Thai Binh co them mo dau mai Kien Xuang A TAI LIEU THAM KHAO Bao cao ket qua nghien cuu dia chat gieng khoan 101 - Cau tao Kien Xuang A 1975 CC Itenberg, 1987 Phdn tieh cdc kit qud nghiin ciru dia vgt ly gieng khoan, Matxeava NEDRA ... Da khang djnh lai cac tap cat chiia cu6i Phii Cir II gap a tren dirt gay co gieng khoan va gieng khoan duoi diit gay VTnh Ninh thuge phan D6ng Nam cau tao Tien Hai C, cau tao Tien Hai A lat cat... KHA NANG CHIJA HC VA KET QUA THlT VIA GIENG KHOAN 101 TREN CAU TAO K I E N XU^ONG A Nhu tren da noi ket qua thu via cac tap da chua a giing khoan 101 co the khong phan anh dung ban ch4t via, ma... day la lat cat chua HC Dk lam sang to van de c^n xac dinh dugc ban kinh doi tham dung dich vao cac via chua qua phan tich cac t6 hgp duong cong BKZ cac dgt karota va ket qua tinh bao boa nuac