Tuygn tap bao cao Hdi nghj KHCN "30 nam Phu Ivhi Viet Nam Co'''' hdi mdi, thach thuc mdi" 61 1 BE TRAM TICH MALAY THO CHU VA TAX NGUYEN DAU KHI Nguyen Thu Huyen, Phiing Sy Tai Viin Ddu Khi Trjnh Xuan Cud[.]
Tuygn tap bao cao Hdi nghj KHCN "30 nam Phu Ivhi Viet Nam: Co' hdi mdi, thach thuc mdi" 61 BE TRAM TICH MALAY - THO CHU VA TAX NGUYEN DAU KHI Nguyen Thu Huyen, Phiing Sy Tai Viin Ddu Khi Trjnh Xuan Cudng Tong cong ty Ddu Viet Nam TOM TAT Tren co s& nghiin ciru tdng hgp mot khdi lugng ldn tdi lieu dia chdt, dia vdt ly da cd sau nhiiu ndm tim kiim - thdm dd vd khai thde ddu vung nghien ciru ciing nhu bd sung nhung tdi lieu m&i, tap thi tdc gid da dung lgi mdt each tdng qudt khung cdnh bi trdm tieh Malay - Thd Chu tir ddc diim phdn tdng cdu true, cdc qud trinh hogt ddng kiin tgo, lich su phdt triin dia chdt, dia tdng trdm tich di tir ddnh gid tiim ndng ddu cua bi Tu nhung kit qud nghien ciru edit true vd tiim ndng ddu bi Malay - Thd Chu, mdt sd vdn di cdn tdn tgi cdn phdi nghien ciru tiip cung da dugc de xudt bdo cdo ndy GIOI THIEU CHUNG Be tram tich Malay - Th6 Chu nam d phia D6ng vjnh Thai Lan (Hinh 1), dugc gidi ban bdi dudng bd bien Tay Nam Viet Nam d phia D6ng, viing bien Campuchia ve phia Tay Bae va viing bien Thai Lan va Malaixia ve phia Tay Nam Be Malay - Th6 Chu dugc hinh qua trinh tach gian keo toac dudi anh hudng ciia dirt gay Ba Chiia Tram tich De tam be chii yeu la tram tfeh luc nguyen c6 noi day den 10km Ve dja chat, day la phan rgng ldn nhat ciia cau tao Bien D6ng, noi co nhieu tai nguyen khoang san quy va nhtrng mo dau co gia trj c6ng nghiep Ngay tir thap ky 1970, cac c6ng ty dau nude ngoai da quan tam dau tu tim kiem tham dau d khu vuc Tir tdi nay, da co nhieu khao sat dia chan cua cac c6ng ty nhu Fina, Unocal da thu n6 vdi ludi tuyen dja chan 2D, 3D va da tien hanh khoan tham do, co nhieu gieng phat hien dau Tuy vay, cac nghien ciru t6ng hgp va chuyen sau chua dugc dau tu dung miic, nhieu van de t6n tai Bao cao se gidi thieu mgt vai ket qua nghien ciru gan day nham tirng bude giai quylt nhtrng t6n tai dd Bg trhm tich Malav - Th6 Chu va tai ngu\xndaii_khi_ 612 THAI- LAN Hinh 1: Vi tri bl Malay - Tho Chu DAC DIEM CAu TRUC DIA CHAT BE MALAY - THO CHU Be Malay - Th6 Chu co dac diem cau true kh6ng nam ngoai dac diem chung ciia cac be tram lich Viet Nam, la co hai tang cau true chinh: trudc De tam va De tam [6, 10] Tang cau triic trudc De tam (Hinh 2) dugc tao bdi nhieu pha kbac thdi ky trudc tao rift, bj u6n nep va phan dj manh bdi cac he th6ng dirt gay theo cac hudng khae Tang bao gom loan bg phirc he mong co ket, bien tinh carbonat, da phun trao xam nhap co tu6i Paleozoi, Mesozoi Phirc he 16 va quan sat thay d cac dao va viing ven ria Tay Nam bg Do tac dgng ciia cac boat dgng dja chat, cac phirc he da bj bien chat d cac mirc khae Trong cac gieng khoan Fina (16 46, 50 51) va Unocal (16 B, 48/95, 52) thuc hien mdi chi gap da mong trudc De tam tai mgt s6 khu vuc d cac ddi nang cao thuoc ria Bae D6ng Bae be Da mong gap tai day chii yeu la da bien chat mirc thap thuge tudng da phien luc da phylit phien sericit xen ke cat bot dang quarzit co the thuoc loat Khorat tu6i Mesozoi Da v6i tu6i tir Carbon muon den Jura dugc phat hien tai gieng khoan Bunga Raya (PM-3) Ting mong trudc De tam dugc danh dau bang tap dja chan SHB va dugc nhan biet bdi cac dac tnmg trudng song dja chan yeu hoae khong co phan xa Dieu phan anh Ihuc the clu triic khii tang, kh6ng phan ldp ciia da mong Tuyen tap bao cao Hdi nghj KHCN "30 nam Phu l Ot z = o z s z >^ 5 I f o ^ f f JS B £ 624 Bg trSm tich Malay - Thd Chu va t^i nguygnjiaujc s u y ti> ban t3& •Sang d a y set t a p TdngK 104*Q0-E 42 lOS'OO'E O SO Km I I I I I C h u giai Ou-o-ng d d n g mii'c k h d n g c h bo;^! giSng k h o a n ( m ) Du'O'ng d o n g mi>c s u y tir ban d dSng d a y set t a p K V "^ Hinh 9: Sff phan bo tang sinh bl Malay - Thi Chu 627 Bg trgm tich Malay - Thd Chu va tainguyenjiaujih[ 628 Tdng I ^ Qua ngu-o'nq tru-ong than ,;_.;i _^_-.i TdngK ::! T r u a n g s m Trud'ng ^ Qua ngu-ong tru-ong than Hinh 10: Sa phan bo mirc truwng bl Malay - Tho Chu Tuygn tap bao cao Hoi nghj KHCN "30 nam Phu Viet Nam: Co hoi mdi, thach thuc mdi" 629 Cac tao chin giir diu bl Malay - Thi Chu dugc phan hai loai chu yeu: • Cdc tdng chdn hgt min, la cac tap set biin tuli Oligocen, Miocen va Pliocen - De tir Cac tap set Oligocen co chilu day ldn tir 50 - 200m vdi ham lugng set cao 80 - 90% ddng vai tro ting chin khu vuc Cac tap set Miocen phan b6 kh6ng lien tuc la cac tang chan dja phuang vdi chilu day thay d6i tir 20 - 60m Cac tap set Pliocen - De tir dat tdi chieu day hang tram met, la tang chan khu vuc cho toan viing vdi ham lugng set 6n djnh tir 85 - 90% Xen ke cac tap set la cac ldp bgt ket m6ng co dac tfnh truang nd cao • Mdn chdn kiin tgo: Che kien tao ciia viing nghien cim co anh hudng va chi ph6i manh me tdi su tich tu va bao t6n dau Cac he th6ng dirt gay la man chan kien tao bet sire quan trgng Hau het cac bay khep kin chieu deu dugc chan bdi cac dirt gay, dac biet la d6i vdi canh nang cac diit gay Nhu vay, be Malay - Th6 Chu la be co tiem nang cao ve dau khi, co the tim thay cac m6 dau va condensat ldn Tru lugng thu h6i tiem nang va da phat hien tai khu vuc theo danh gia ciia VITRA la: Triiu m quy ddu Phat hien 146,88 Tiem nang 290,99 Tdng cgng 437,87 KET LUAN Be tram tich Malay - Th6 Chu hgi tu dii cac dieu kien ciia mgt be tram tich chira dau Qua trinh hinh va dac diem cau triic dja chat bj chi ph6i manh bdi cac boat dong kien tao ciia khu vuc lan can Tram tich De tam co tu6i tir Oligocen den hien tai vdi chieu day thay d6i tir vai tram met den 7000m vdi don vj dia tang la he tang Kim Long, Ngge Hien, Dam Dai, Minh Hai va Bien D6ng Cac tap set Oligocen va Miocen sdm giau VCHC la tang da me chinh cua khu vuc Da me Oligocen cd ngu6n g6c agal dam h6 co kha nang sinh dau Da me Miocen co nguon g6c luc dja va dam h6 chii yeu sinh Cac tap cat ket Oligocen, Miocen giua mugn dugc hinh m6i trudng chau th6, phan b6 hep, co chieu day m6ng, r6ng thay doi tir 15 - 30% la da chiia chinh cua viing Tang chan la cac tap set nam xen ke cac tang chira Oligocen, Miocen va Pliocen - De tir He th6ng diit gay co vai tro chin giir dau T6ng tiem nang dau be tram tfeh Malay - Thi Chu du bao khoang 438 trieu m^ dau quy d6i, da phat hien 147 trieu m-^ va 29 Im^ tiem nang (thien ve tiem nang khi) Tuy nhien, van cdn mgt s6 van dl tin tai cin dugc nghien ciiu tilp, dd la tiem nang dau ciia d6i tugng m6ng trudc De tam ciing nhu viec chinh xac hoa ranh gidi dia ting Eocen/Oligocen, ranh gidi De tam/De Hi 630 Bg tram tich Malav - Thd Chu va tai nguyen dau TAI LIEU THAM KHAO D6 Bat va n.n.k., 2000 Dia tdng vd qud ii'inh phdt irien trdm tich De tam them luc dia Viet Nam Tuyen tap bao cao Hgi nghi Khoa hgc - C6ng nghe "Ngdnh Ddu tru&c thim thi ky 2P\ NXB Thanh nien, tr 92 - 99 D6 Bat va n.n.k., 2001 Dia tdng tdng hgp trdm tich Di tam them luc dia Tdy Nam Vid Nam Tuyen tap bao cao khoa hoc ky niem 20 nam lap XNLD Vietsovpetro va khai thac tan dau thir 100 trieu, tr 216 - 219 D6 Bat va n.n.k., 2003 Dinh danh vd liin kit dia tdng trdm tich Di tam them luc dia Tdy Nam Viet Nam Tuyen tap bao cao Hgi nghj Khoa hgc - C6ng nghe ''Viin Ddu Khi: 25 ndm xdy dung vd tru&ng thdnh'", NXB Khoa hgc va Ky thuat, tr 238 - 249 Nguyen Thj Thanh Binh, 2000 M6 hinh nhiet va dja boa dgng lire nghien cim ljch sir tien boa be tram tich va sinh dau - ap dung cho them luc dja Tay Nam Viet Nam Tuyen tap bao cao Hoi nghj Khoa hoc - C6ng nghe "Ngdnh Ddu tru&c thim thi ky 2r, NXB Thanh nien, tr 206 - 226 Nguyen Van Dac, Vii Van Kfnh va n.n.k., 2002 Tdng hgp ddnh gid kit qud tim kiim thdm dd ddu & Viet Nam giai dogn 1988 - 2000 vd phuong hu&ng tim kiim thdm dd tiep theo Bao cao t6ng ket de tai cap Nganh, Ha Ngi Phan Trung Dien, 1996 Su phdn bd vd ddnh gid triin vong ddu cita cdc thdnh tgo dia chdt tru&c Kainozoi thim lue dia Viet Nam Bao cao t6ng ket de tai KT-01-17, Ha Noi Brian Taylor et al., 1989 The tectonic evolution of South China basin The tectonic and geologic evolution of Southeast Asia , Editor Seas and Island Claude Rangin et al., 1995 Cenozoic deformation of Central and South Vietnam Tectonophysics 251, p 209 - 222 Emary K.O., Avraham Z., 1982 The structure and stratigraphy of the China basin and oil potential of China continental shelf Bull Am Assoc Petrol Geols., Vol 56 10 Fraser A.J., Matthews S.J., Murphy R.W., 1997 Petroleum geology of Southeast Asia Geological Society Special Publication ll.PetroFina, 1992 Hydrocarbon prospectivity of blocks 45, 46, 49, 50, 51, 53, 54, 55 12 Unocal, 1998 n.Truong Son JOC, 2001 ... Th6 Chu va tai ngu\xndaii_khi_ 612 THAI- LAN Hinh 1: Vi tri bl Malay - Tho Chu DAC DIEM CAu TRUC DIA CHAT BE MALAY - THO CHU Be Malay - Th6 Chu co dac diem cau true kh6ng nam ngoai dac diem chung... mirc truwng bl Malay - Tho Chu Tuygn tap bao cao Hoi nghj KHCN "30 nam Phu Viet Nam: Co hoi mdi, thach thuc mdi" 629 Cac tao chin giir diu bl Malay - Thi Chu dugc phan hai loai chu yeu: • Cdc... tich hi Malay - Tho Chu Tuygn tap bao cao Hoi nghj KHCN "30 nam D5u Viet Nam: Co hdi mdi, thach thuc mdi" Miocen giira Pliocen - Di tir Hinh 6c: So moi truong tram tich be Malay - Thi Chu 621