886 Dac digm phan bd cac khoang cho ddng san pham trong cac cau tao Bach Hd va Pdi Moi JC / • DAC DIEM PHAN BO CAC KHOANG CHO DONG SAN PHAM TRONG CAC CAU TAO BACH HO, RONG VA DOI MOI Phiing Dinh Thuc,[.]
886 Dac digm phan bd cac khoang cho ddng san pham cac cau tao Bach Hd va Pdi Moi JC /• DAC DIEM PHAN BO CAC KHOANG CHO DONG SAN PHAM TRONG CAC CAU TAO BACH HO, RONG VA DOI MOI Phiing Dinh Thuc, Mai Van Du Cong ty Thdm - Khai thde Ddu TOM TAT Trin co s& phdn tich kit qud minh gidi tdi lieu ddng bdng mat cdt nhiet, vd kiim tra khai thde tgi cdc giing khoan cua cdc cdu tgo Bgch Ho, Ddng Nam Rdng vd Ddi Mdi, cdc tdc gid nhgn thdy nhin chung dd mdng cua cdc cdu tgo trin diu cd xu thi phdn bd ty phdn cdc khodng cho ddng cao & nde cdu tgo vd ty phdn trin cdng xudng sdu cdng gidm ddn Tuy nhiin, mdng md Bgch Hd vdn cd d&i cd ty phdn cdc khodng cho ddng cao & chiiu sdu 4000 - 4200m tuc Id thdp hon nde via gdn 1000m, hay & cdu tgo Ddng Nam Rdng thi ty phdn trin lgi cd xu thi tdng ddn tu nde mdng xudng din chiiu sdu du&i nde mdng 100 - 200m, sau dd m&i c& xu thi gidm ddn theo chiiu sdu Tgi giing khoan DM-IX cua cdu tgo Ddi Mdi thi khodng cho ddng tdt nhdt lgi phdn bd & day giing khoan gdn v&i biin du&i cua cdu tgo ndy Phdn tich kit qud ddng kit hgp v&i tdi lieu dia chdn vd tdi lieu log cho thdy da mdng Bgch Hd v&i iy phdn rdng nirt ni nhiiu hon thi cdc khodng cho ddng sdn phdm cd xu thi phdn bd chu yiu & gdn cdc dirt gdy kiin tgo hay & ranh gi&l giira hai khdi cd thdnh phdn thgch hgc khdc nhau, cdn da mdng cua Ddng Nam Rdng vd Ddi Mdi v&i ty phdn rdng hang hde nhiiu hem thi cdc khodng cho ddng sdn phdm ciing phdn bd nhu tren nhung hdu nhu Id chi & cdc khdi da cimg (da axit) md thdi Diiu ndy mdt ldn nira khdng dinh tinh phuc tgp vd bdt ddng nhdt cao cua dge tinh thdm chua cua cdc via ddu mdng G l l THIEU cac cau tao Bach Hd, Ddng Nam Rdng va Doi Mdi la nhiing clu tao da phat hien dau da mdng granitoid thudc bdn triing Cuu Long Via diu mdng md Bach Hd da dugc dua vao khai thac tir nam 1988, via diu mdng Ddng Nam Rdng tu nam 1996 den Gieng khoan dau tien tai clu tao Ddi Mdi cung da phat hien cd dau da mdng Nghien ciiu chi tiet su phan bd cac ddi cho ddng san phim da mdng se cung cap nhiing thdng tin cin thilt giiip cho cac ky su dia chit va cdng nghe md xay dung md hinh dia chit, lap cac phuang an khai thac md ciing nhu dua nhiing giai phap nham nang cao hieu qua ciia cdng tac tham dd ciing nhu khai thac dau tai cac cau tao tren Vdi muc dich tren, cac tac gia da tiln hanh phan tich ti mi va tdng hgp lai tit ca cac kit qua xii ly ddng nhim dua biic tranh phan bd chi tiet cac khoang cho ddng da mdng ciia cac clu tao tren Ket qua nghien ciiu duoc trinh bay d bao cao Tuygn tap Mo cao HQi nghj KHCN "30 nam Phu khf Viet Nam: Cff hdi mdi, thach thuc mdi" 887 DAC DIEM PHAN BO CAC KHOANG CHO DONG TRONG DA MONG CAC CAu TAO BACH HO, DONG NAM RONG vA DOI MOI Dac dilm phan bo cac khoang cho dong da mong Bach Ho Viec phan tich toan bd kit qua minh giai cac lugt ddng ke ca bang mat cat nhiet lin luu lugng ddng kit hgp so sanh vdi ket qua minh giai tai lieu log gieng khoan cho phep chiing tdi dua dac diem phan bd cac khoang cho ddng than dau mdng md Bach Hd nhu sau: Khoang tren cimg ciia via dau (3050 - 3100m) dugc dac trung bdi ty phan cac khoang cho ddng cao nhat 68% Theo tai lieu log thi ty phan ciia da chira d khoang la 85% Ty phan cac ddi tham chiia cua da granitoid mdng md Bach Hd giam dan theo chieu sau (Hinh 1) Neu nhu khoang phia tren (3100 - 3500m) cd ty phan cac khoang cho ddng 47 - 45%) va 56 - 52% da chiia theo tai lieu log, thi d khoang dudi ciing (4500 - 5000m) - ty phan cac ddi da chiia thudng nhd hon 10%) va hau nhu khdng cd cac khoang cho ddng d chieu sau Noi sau nhat cd khoang cho ddng dugc xac dinh tai thdi diem hien tai la 4528m (gieng khoan BH-484) Hinh 1: Phan bo ty phan da chua mong mo Bach H6 theo chieu sau - Theo sd lieu ddng cita 38 giing khoan; - Theo sd lieu log cua 19 giing khoan Dac diem phan bd cac khoang cho ddng san pham cac cau tao Bach Hd va Pdi Mdi 888 Ty phin cac khoang cho ddng nhd hon so vdi ty phin cua da chiia theo tai lieu log gieng khoan ciing dugc giai thich la khdng phai toan bd cac ddi da chiia theo tai lieu log gieng khoan deu cd kha nang cho ddng san pham Mac dii ty phan cac ddi tham chiia ciia da granitoid mdng md Bach Hd giam din theo chieu sau nhung ve tdng the cd the phan chia toan bd mat cat mdng khoang cd mat xuat hien cac khoang cho ddng cao, dd la khoang cd mat ldn nhit cd chieu sau tir nde mdng den 3500m va khoang thii hai cd mat tuong ddi nhd hon vdi chilu sau 4000 - 4200m (Hinh 1, 2, 3) Theo ket qua ddng cua 34 gieng khoan sau nhat mdng Bach Hd cd the khang dinh rang, ranh gidi dudi (cd gia tri cdng nghiep) cua than dau la mdt mat gd ghe vdi chieu sau tuyet ddi tir 3600 den 4528m, tiic la vdi bien dao ddng len den khoang 1000m (Hinh 2, 3) phan Trung tam ciia mdng, ranh gidi dudi ciia than dau cd chieu sau ldn nhat vdi bien dao ddng nhd, dac biet la d khdi Trung tam, noi nd dao ddng pham vi tu 4000 den 4528m (Hinh 2) Cang tien gan den cac khdi phia Bae, khu vuc Ddng Bae va Nam ciia khdi Trung tam, ranh gidi cang cd hinh thai phiic tap vdi bien dao ddng that thudng khoang tu 3600 den 4400m (Hinh 2, 3) Khu vuc phia Tay cua khdi Trung tam cd mat ranh gidi dudi ndng d phan phia Bae va phia Nam (tu 3700 den 3800m) va sau hon d phan Trung tam ciia nd: 4300 4528m B - B TM TD2 C02 C11 COS cv> C20 BK) BOS B3OB64 B33B21B09 BT7 93, 943 838 B24 Hinh 2: Phan bo khoang cho dong phan giua khoi Trung tam mong mo Bach H6 Tuygn tap bao cao Hdi nghj KHCN "30 ngm Dgu Viet Nam: Cff hdi mdi, thach thuc mdi" B32 OJBB" B26 B62 B76 857 B16 366 B62 889 B49 3000 3100 H Hinh 3: Phan bo khoang cho dong phia Dong khoi Trung tam mong mo Bach Ho Dac diem phan bo cac khoang cho dong da mong cac cau tao Dong Nam Rong va Doi Moi Nghien ciiu su phan bd cac khoang cho ddng mdng cua cau tao Ddng Nam Rdng ket hgp vdi tai lieu log gieng khoan va dia chan 3D cho phep chiing tdi dua mdt sd nhan xet sau: cac khoang cho ddng rat it gap d phan tren cung cua mdng noi cd su hien dien ciia da phun trao Chiing chi bat dau xuat hien nhieu d ranh gidi giira ldp da phun trao vdi da mdng tuoi Tir nde mdng din chilu sau thap hon nde mdng 100 - 200m, ty phan cac khoang cho ddng cd xu thi tang din Khoang chieu sau cd ty phan cho ddng va luu lugng cua chiing cao nhit la each dudi mat mdng tu 100 den 250m Sau dd, ciing nhu da mdng Bach Hd, ty phan cac khoang cho ddng giam dan theo chieu sau (Hinh 4, 5) 250 Ot_R305 200 c • b_R305 At_R201 150 - Xb_R201 9t:t_R206 O b_R206 100 |P_R21 • b_R2-| 50 Bt_R14 • b R14 2250 2300 2350 2400 2450 2500 2550 2600 2650 2700 2750 2800 2850 2900 Chieu sau, m Hinh 4: Mong Dong Nam Rong - phan bo cac khoang cho dong theo chieu sau 890 D§c digm phan bd cac khoang cho ddng san pham cac c§u tao Bach Hd va Ddi Moi 250 •CD C 200 150 - ? 100 150 200 250 300 350 400 450 500 550 600 Chieu sau tinh ti> mat mong, m Hinh 5: Mong Dong Nam Rdng - phan bo cac khoang cho dong so vol mat mong Gidng nhu mdng Bach Hd, cac khoang cho ddng chinh ciing cd xu the phan bd chii yeu d gan cac diit gay kien tao va ranh gidi giiia cac khdi da cd phan thach hgc khae nhau, nhung dieu khae biet la chimg hau nhu chi hien dien d cac khdi da cung gidn (da axit) vdi ty phan rdng nut ne nhilu ban va ty phin rdng hang hde it ban so vdi nhiing khdi da mdng khae cua cau tao Ddng Nam Rdng (Hinh 6,7) 250 I 200 BJ) ,5 150 100 50 # Đ đđ 50 100 ,150 ,200, 250 Klioang each den diit gay gan nhat m 300 HJnh 6; Mong Dong Nam Rong - phan bo cac khoang cho dong so \6i dirt g^y R21 NPHI / DT A c t i v e Z o n « : 4- B4 -1 T 11 IS IIPHI 19 23 27 3i 35 p o i n t s p l o t t e d o u t of Zone Depthiss * ( ) BA 2S90.M - 2TSd.M Hinh 7a: Gieng khoan R21 cSu tao Dong Nam Rdng - bilu d6 NPHI/DT ciia khoang cho dong chinh vol da m6ng co rong nirt ne nhieu hon Tuyen tap bao cao Hdi nghj KHCN "30 nam D^u Viet Nam: Cff hdi mdi, thach thuc mdi" 891 R21 NPHI DT A c t i v e Z o n e s : V * Z : , 6, 11 15 IIPHI i» 23 27 31 35 p o i n t s plotted out of Zone Depicts > (1)B1 M - 2JieO.M X (3)B3 251D.M - 2530.M * (ejBB 23TO.M - 0 M Hinh 7b: Gieng khoan R21 cau tao Dong Nam Rong - bieu NPHI/DT cua cac khoang khong cho dong vol da mong co rong hang hoc nhieu hon Tir mdi quan he giira khoang each den cac diit gay chinh mdng chiing tdi nhan thay cang xa dut gay thi ty phan cac khoang cho ddng cang giam dan Tuy nhien, cac khoang cho ddng vdi luu lugng ldn nhat lai phan bd pham vi each xa cac diit gay chinh tir 50 den 150m Cach xa cac diit gay hon 250m thi hau nhu khdng cdn xuat hien cac khoang cho ddng mdng Ddng Nam Rdng Theo tai lieu ciia gieng khoan nhat (DM-IX) tai cau tao Ddi Mdi thi khoang cho ddng chinh (chiem gan 90% luu lugng gieng khoan) la d khoang chieu sau dudi cimg cua gieng 3778 - 3808m, dudi nde mdng chung 500m va rat gan vdi bien dudi ciia cau tao (3910m) Theo tai lieu log gieng khoan va dia chan 3D thi gieng khoan cat diit gay kien tao d khoang cho ddng va day ciing la khoang cd da mdng Cling gidn vdi ty phan rdng hang hde it hon, ty phan rdng nut ne nhieu hon so vdi toan bd da mdng phia tren ma gieng khoan di qua, ke ca phan da mdng cd diit gay cat qua nhung lai dugc dac trung bdi nhieu rdng hang hde, it rdng mit ne cung nhu luu lugng ddng ciia khoang it hon (Hinh 8) 892 t)ac digm phan bd cac khoang cho ddng san pham cac cSu tao Bach Hd v^ Ddi Mdi NPHI RHOB Aetfve Z o n e : e O 0.03 0.ôC 0.09 ft.12 0.15 ãIPHI t>ii&& O.ia 0.21 0.2-ằ 0.27 0.3 p o i n t a : p l o t t a d o u t of e Zorio Das2 SJtSO.M - SSOO.Ivl > (4.)pss:4 ssoo.M - seeo.M Hinh 8b: Gieng khoan DM-IX cau tao Doi Moi - bilu do rong - mat cua c^c khoang cho ddng yeu v61 dd m6ng c6 tinh axit it hon Nhu vay, ddi vdi nhiing eau tao nhu Ddi Moi, Ddng Nam Rdng va kl ca Bach Hd, ben canh yeu td kien tao thi phan thach hgc cQng cd vai trd quan trgng, anh hudng den sir phan bd ciia cac khoang cho ddng da mdng, dae biet la cac khoang cho ddng vdi luu lugng ldn KET LUAN Dac diem phan bd cac khoang eho ddng mdng cac cau tao Bach Hd, Ddng Nam Rdng va Ddi Mdi rat phiic tap vdi xu the chung cd ty phan giam Tuygn tap bao cao Hdi nghj KHCN "30 nam D2u Viet Nam: Cff hdi mdi, thach thuc mdi'' 893 dan theo chilu sau Tuy nhien, mdng Bach Hd van cd ddi cd ty phin cac khoang cho ddng ldn d chilu sau 4000 - 4200m Ddng Nam Rdng thi ty phan tren lai cd xu thi tang dan tu nde mdng xudng den chieu sau dudi nde mdng 100 - 200m, sau dd nd mdi cd xu the giam dan theo chieu sau Tai gieng khoan DM-IX ciia cau tao Ddi Mdi thi khoang cho ddng tdt nhat lai phan bd d day gilng khoan gan vdi bien dudi ciia cau tao Nhiing khoang cho ddng chinh mdng ciia cac cau tao tren thudng phan bd gan cac dut gay kien tao hay ranh gidi giira cac khdi da cd phan thach hoc khae nhung chi cac khdi da ciing gidn (da axit - granit) la cd kha nang cho ddng vdi luu lugng ldn hon nhieu so vdi cac da mdng khae Nghien ciiu chi tiet su phan bd cac khoang cho ddng da mdng se gdp phan lam chinh xac hda md hinh dia chat va giup dua nhiing giai phap nang cao hieu qua cdng tac tham dd va khai thac dau cua cac cau tao tren TAI LIEU THAM KHAO Phiing Dinh Thuc va n.n.k., 1999 Cdng nghi vd ky thugt khai thac ddu NXB Giao due Ha Ndi TeKynmii aHajina u KOHTpon& sa papadoTKoii MecTopoKfleHHH "Benbm Tnrp" n yTOHHCHHe ypoBHJi jxo^hiHVL He(|)TH Ha 1994 -1995 r C yncTOM aonojiHHTejibHoii reonoro-npoMbicjiOBoii UHcJiopMauHH OTMCT H H H H H CH BbeTCOBnexpo no TCMC HHP-8-1994r Tran Le Ddng, Mai Van Du, 2001 Ddc diim phdn bd cdc d&i cho ddng sdn phdm vd tiip nhgn nu&c thdn ddu mdng md Bgch Hd HNKH ky niem 20 nam lap XNLD Vietsovpetro, Viing Tau ... thach thuc mdi" 887 DAC DIEM PHAN BO CAC KHOANG CHO DONG TRONG DA MONG CAC CAu TAO BACH HO, DONG NAM RONG vA DOI MOI Dac dilm phan bo cac khoang cho dong da mong Bach Ho Viec phan tich toan bd... khoan cho phep chiing tdi dua dac diem phan bd cac khoang cho ddng than dau mdng md Bach Hd nhu sau: Khoang tren cimg ciia via dau (3050 - 3100m) dugc dac trung bdi ty phan cac khoang cho ddng... Phan bo khoang cho dong phia Dong khoi Trung tam mong mo Bach Ho Dac diem phan bo cac khoang cho dong da mong cac cau tao Dong Nam Rong va Doi Moi Nghien ciiu su phan bd cac khoang cho ddng mdng