Dia Chat Va Tai Nguyen Dau Khi Viet Nam - Chuong 7

7/23/2019 Dia Chat Va Tai Nguyen Dau Khi Viet Nam - Chuong 7

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Be tram tchSong Hong va

tai nguyendau kh

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Chng 7. Be tram tch Song Hong va tai nguyen dau kh

Be Song Hong nam trong khoang105030- 110030 kinh o ong, 14030-21000v o Bac. Ve ia ly, be Song Hong

co mot phan nho dien tch nam tren at lienthuoc ong bang Song Hong, con phan lndien tch thuoc vung bien vnh Bac Bo vabien mien Trung thuoc cac tnh t QuangNinh en Bnh nh. ay la mot be co lpphu tram tch e Tam day hn 14 km, codang hnh thoi keo dai t mien vong HaNoi ra vnh Bac Bo va bien mien Trung

(Hnh 7.1). Doc ra pha Tay be troi lo caca mong Paleozoi-Mesozoi. Pha ong Bactiep giap be Tay Loi Chau (Weizou Basin),pha ong lo mong Paleozoi-Mesozoi aoHai Nam, ong Nam la be ong Nam HaiNam va be Hoang Sa, pha Nam giap betram tch Phu Khanh.

Trong tong so dien tch ca be khoang220.000 km2, be Song Hong ve pha VietNam chiem khoang 126.000 km2, trong ophan at lien mien vong Ha Noi (MVHN)va vung bien nong ven b chiem khoanghn 4.000 km2, con lai la dien tch ngoaikhi vnh Bac Bo va mot phan bienmien Trung Viet Nam. Cong tac tm kiemtham do (TKTD) dau kh be Song Honga c tien hanh t au thap ky 60 cua

the ky trc, nhng chu yeu ch c thchien tren at lien va en nam 1975 a phat

hien c mo kh Tien Hai C (TH-C). Tkhi co chnh sach oi mi, nhat la khi coluat au t nc ngoai, be Song Hong c

tang cng au t nghien cu va TKTD catren at lien va phan ngoai khi vi 12 hpong phan chia san pham (PSC) va cungieu hanh (JOC).

Tren phan lanh tho Viet Nam cua beSong Hong a khao sat tong cong hn80.000 km tuyen a chan 2D va 1200 km2a chan 3D, nhng phan bo khong eu,

tap trung chu yeu cac lo at lien, ven caSong Hong va bien Mien Trung. a khoantren 50 gieng tm kiem tham do (tren atlien: 27 gieng, ngoai khi: 24 gieng), comot phat hien kh at lien a va ang khaithac. ngoai khi tuy a phat hien kh,nhng cha co phat hien thng mai quantrong e co the tham lng va phat trienmo. Trong khi o, phan dien tch thuoc lanhhai Trung Quoc a co nhieu phat hien dauva kh, co nhng phat hien quan trong a ivao phat trien va khai thac.

Be Song Hong rong ln, co cau truc achat phc tap thay oi t at lien ra bientheo hng ong bac - tay nam va nam, baogom cac vung a chat khac nhau, oi tngTKTD cung v the ma khac nhau. Co the

phan thanh ba vung a chat (Hnh 7.1). Vung Tay Bac bao gom mien vong Ha

1. Gii thieu


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a chat va tai nguyen dau kh Viet Nam

Noi va mot so lo pha Tay Bac cua vnh

Bac Bo. ac iem cau truc noi bat cua

vung nay la cau truc uon nep phc tap

kem nghch ao kien tao trong Miocen.

Vung trung tam t lo 107-108 en lo

114-115 vi mc nc bien dao ong

t 20-90 m. Vung nay cung co cau truc

a dang, phc tap, nhat la tai phu beHue-a Nang, nhng nhn chung co

mong nghieng thoai dan vao trung tam

(depocentre) vi o day tram tch hn

14.000 m. Cac cau tao noi chung co cau

truc khep kn ke tha tren mong pha

Tay, en cac cau truc set diapir noi bat

gia trung tam.

Vung pha Nam t lo 115 en lo 121, vi

mc nc thay oi t 30-800 met nc,co cau truc khac han so vi hai vung noi

Hnh 7.1. V tr va phan vung cau truc a chat be Song Hong(1) Vung Tay Bac; (2) Vung Trung Tam ; (3) Vung Pha Nam

1

2

3

1

2

3

BE TAY LOICHAU

ao Hai Nam

Viet Nam

Lao


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tren v co mong nho cao tren a luy TriTon tao them carbonat va am tieu sanho, ben canh pha Tay la a hao QuangNgai va pha ong la cac ban a hao

Ly Sn co tuoi Oligocen.Trong hang chuc nam qua, tai lieu cua

cac nha thau dau kh (ma phan ln chac cong bo) a giup ch rat nhieu lamsang ro cau truc a chat va he thong daukh be Song Hong. Ngoai cac tai lieu trenchung toi a s dung rat nhieu tai lieu cuaVien Dau kh (VPI), cua Cong ty au t-

Phat trien Dau kh (PIDC), cung nh cacvan lieu cong bo cua cac nha nghien cutrong va ngoai nc nh a neu phan tailieu tham khao.

2. Lch s tm kiem, tham do va khaithac dau kh

Cong tac TKTD va khai thac dau khbe tram tch Song Hong c thc hientrc tien ong bang Song Hong. Lch snghien cu, ket qua TKTD & KT co thechia lam hai giai oan chnh, trc 1987 vat 1988 en nay.

a. Giai oan trc 1987

Giai oan nay ch tap trung khao sat chuyeu mien vong Ha Noi, la ni m rong vepha Tay Bac cua be Song Hong vao atlien, la vung c nghien cu a chat daukh ngay t au nhng nam 60 vi s giup ve tai chnh va cong nghe cua Lien Xocu. Hai phng phap tham do au tien lakhao sat t hang khong va trong lc (1961-1963) vi ty le 1/200.000. Sau o, trong cacnam 1964, 1967, 1970-1973, 1976 va 1980-1982, 1983-1985 a tien hanh nghien cu

trong lc chi tiet hn tai mot so vung (phanong Nam dai Khoai Chau-Tien Hai, Kien

Xng) at ty le 1/50.000-1/25.000. Tuyvay, cac phng phap x ly tai lieu trcay chu yeu la thu cong nen o chnh xackhong cao. Cac ket qua minh giai chu yeu

mang tnh khu vc. Cha xay dng ccac s o cau truc ty le tng xng vimc o tai lieu a co.

Tiep theo la cong tac tham do ien cautao c thc hien trong cac nam 1964-1969 tren dien tch 26.000 km2 vi ty le1/200.000. Con vung Tien Hai, KienXng a c th nghiem cac phng

phap tham do ien khac nhau nh o sauien, o sau t-telua, dong telua vi ty le1/100.000 va 1/25.000. Han che chung cuacac nghien cu nay la phan bo chu yeu phan trung tam mien vong vi mat o khaosat mang tnh khu vc. a so tai lieu cochat lng thap, ket qua co o tin cay kem.Mat khac do thieu so lieu ve chieu sau cua

mong ket tinh nen viec giai thch tai lieugap kho khan va s o dng c co o tincay khong cao.

Vi muc ch nghien cu cau truc khuvc va tm kiem cac cau tao co trien vongdau kh, ong thi vi cac phng phapnghien cu a vat ly neu tren a tien hanhtham do a chan khuc xa (1962-1973),phan xa (1973-1975) va phan xa iem sauchung (1975 en nay) vi cac ty le khacnhau t 1/200.000-1/25.000. Khoang tren9.000 km tuyen a chan c thu no bangcac tram may ghi tng t (analog) SMOVcu cua Lien Xo trc ay hoac bang cactram ghi so (digital) SN338B cua Phap enghien cu cau truc sau vi ty le 1/50.000-1/25.000. Noi chung cac khao sat a chan

phan xa mi tap trung khu vc trung tammien vong Ha Noi, tren cac n v cau truc


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nh trung ong Quan, trung Phng Ngai,dai nang Tien Hai, Kien Xng. Con cacvung ra ong Bac va Tay Nam hau nhkhong co hoac co rat t tai lieu a chan.

Han che cua loat tai lieu nay la o saunghien cu khong ln do cong nghe thu nova x ly cha cao, nen ch quan sat ccac mat phan xa t ay Phu C tr len.

Con ngoai khi, pha Bac be SongHong trc nam 1975 hau nh khong cocac hoat ong nghien cu a vat ly, nhng pha Nam cua be co hai mang li tuyen

a chan khu vc khao sat nam 1974: mangWA74-PKB (5.328 km) khao sat ven bienmien Trung va mang WA74-SHV (3.373km) khao sat t ong lo 121-117 m rongsang pha ong cac lo 141-144 qua cac aoHoang T Anh, Hoang T Em thuoc quanao Hoang Sa. Nhng khao sat khu vc cotnh he thong ch mi c bat au t nam

1981 va trien khai tng oi manh trongcac nam 1983-1988. Trong giai oan naya thu no 19.024 km tuyen, trong o 11.875km bang tau Iskatel, Poisk va Malgin(Lien Xo cu), so con lai do Tong Cuc DauKh Viet Nam t to chc thc hien bang tauBnh Minh. Nhn chung chat lng tai lieukhong cao.

Ve cong tac khoan, t nam 1967-1968a tien hanh khoan 21 lo khoan nong, veban o co chieu sau t 30-150m. T nam1962-1974 a tien hanh khoan 25 giengkhoan cau tao co chieu sau t 165-1.200mvi tong khoi lng khoang tren 22.000 mkhoan. Ket qua cac gieng khoan va tai lieua chat thu c a bc au cho thay bctranh cau truc va trien vong dau kh cua

MVHN. T nam 1970-1985 MVHN akhoan 42 gieng khoan tm kiem tham do va

khai thac kh co chieu sau t khoang 600-4.250m vi tong khoi lng khoang tren100 nghn met khoan. Trong so 11 dien tchgom cau tao, ban cau tao khep vao t gay

, cau tao dang mui, i vat nhon a tang akhoan tm kiem ch phat hien c mot mokh nho TH-C vao nam 1975. Nam 1981 monay c a vao khai thac dung cho phatien va cong nghiep a phng tnh ThaiBnh. Do kho khan ve von va cong nghe bhan che t nam 1985 cong tac tham do daukh tam ngng, hoat ong ay ch duy tr

khai thac kh mo Tien Hai C.b. Giai oan t 1988 en nay (2004)

T khi Luat au t nc ngoai c banhanh cong tac tm kiem tham do dau kh them luc a Viet Nam bc vao giai oanhoat ong m rong va soi ong tren toanthem, trong o co be Song Hong.

T nam 1988 en nay a co 12 hp

ong dau kh c ky ket e TKTD beSong Hong, trong o 9 hp ong a ket thucdo khong co phat hien thng mai (Total,Idemitsu, Shell, OMV, Sceptre, IPC, BP, vaBHP), hien con 3 nha thau ang hoat ongla Petronas (PSC lo 102-106), Vietgasprom(JOC lo 112) va Maurel&Prom (MVHN).

Sau khi ky hp ong cac nha thau a tchcc trien khai cong tac khao sat a chan vakhoan tham do. mien vong Ha Noi nam1994-1997, Cong ty Anzoil a thc hien 3t thu no a chan 2D vi khoi lng 2.214km tuyen a chan 2D, trong o co 813 kmtuyen vung nc nong ven b. ieu angnhan manh ay la, mac dau tai lieu mico chat lng tot hn han, nhng phan dimat cat ni co oi tng cha kh Oligocen

van cha c ro rang. Ket qua cua cac tkhao sat sau cung a chnh xac hoa c


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cau truc, phat hien them c cac cau taomi nh B10, D14, K2 (Hnh 7.2).

Tren c s nghien cu cac van ekien tao, a tang, tram tch, moi trng

va phan tch he thong dau kh, Anzoil a

phan ra 3 i trien vong gan lien vi 3 loaibay dau kh can TKTD nh : (1) i cautao vom kem t gay xoay xeo Oligocen(Oligocene Tilted Fault Blocks) chu yeu

phan bo trung ong Quan; (2) i cac

Hnh 7.2. Ban o cau truc mien vong Ha Noi (theo Anzoil, 1996 & PIDC, 2004)


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cau tao chon vui (Burried Hills Trend) via carbonat hang hoc va nt ne phan bo ra ong Bac MVHN; (3) i cau taonghch ao Miocen (Miocene Inverted

zone) phan bo trung tam va ong NamMVHN (trc ay thng c goi la dainang Khoai Chau/Tien Hai/Kien Xng).Quan iem tham do cua Anzoil la: tm khva condensat i 1&3, tm dau i th2, nhng tap trung u tien TKTD i 1& 2. Cac gieng khoan a c Anzoil tienhanh khoan t 1996-1999 theo quan iem

o va mc o nao o a thanh cong: 7trong so 8 gieng a co dau hieu tot en rattot, co mot phat hien kh (D14-1X) va motphat hien dau (B10-1X).

T nam 2002, Cong ty dau khMaurel&Prom (Phap) thay the Anzoilieu hanh tai MVHN, a khoan them haigieng B26-1X va B10-2X nham tham do

va tham lng oi tng carbonat nhngkhong thanh cong. Cung trong nam 2001-2002, PIDC a khoan tiep 2 gieng khoan:(1) gieng khoan tren cau tao Phu C (PV-PC-1X) la mot cau tao nghch ao dainang Khoai Chau-Tien Hai, at chieu sau2000m, ket qua khong nh mong i; (2)gieng khoan tren cau tao Xuan Trng(PV-XT-1X) at chieu sau 1877m, giengkhoan khong gap mong nh d kien nhnggieng co bieu hien tot ve kh va condensat,mat cat cho thay tai ay co a me Oligocentot vi tong ham lng carbon hu c ratcao, co tiem nang sinh dau.

Con ngoai khi (lo 101 en 121) tnam 1989 en nay, cong tac khao sat avat ly be Song Hong chu yeu do cac nha

thau nc ngoai thc hien theo cam ket cuahp ong dau kh. Cac nha thau dau kh

nc ngoai a thu no 51.054 km a chan2D va 450 km2 a chan 3D. Song song vicac hoat ong cua cac nha thau nc ngoai,Petrovietnam cung a trien khai nhieu hoat

ong TKTD be Song Hong nh thc hienkhao sat a vat ly khong oc quyen 3.173km tuyen khu vc vi Geco-Prakla (1993),hoan thanh cac nghien cu chung (JointStudy) vi Arco (1995), Mobil (1997-1998).Cac nam 1995, 1996, Cong ty Tham do-Khai thac (PVEP) a thu no 4.960 km tuyenva a phat hien ra 5 cau tao co lien quan ti

diapir set va am tieu san ho co trien vongdau kh lo 113. T nam 1998-2003 Congty au t Phat trien Dau kh (PIDC/PVSC)a thu no 2.923 km 2D va 831 km2 a chan3D tai lo 103 nham chuan b cau tao chochien dch khoan tham do sap ti. Tnh ennay, ngoai khi be Song Hong a thu notong cong khoang 86.000 km tuyen a chan

2D (at mat o nghien cu 0,70 km/km2

) va1.281 km2 a chan 3D.Cong tac khoan tham do ngoai khi

be Song Hong chu yeu cung do cac nhathau dau kh thc hien. T nam 1990 ennay a khoan 25 gieng, trong o cac nhathau khoan 24 gieng va Tong cong ty Daukh/PVSC (PIDC) khoan 1 gieng, bnh quan2.900 m/gieng. Gieng nong nhat la gieng104-QV-1X tren cau tao Qua Vai (lo 104cua OMV) at 1.050 m, gieng sau nhat la112-BT-1RX cua Shell tren cau tao BachTr at 4.114 m. Bnh quan co 2,1 giengkhoan tren mot lo hp ong. Mat o khoanla 1 gieng/6.100 km2. Trong so 25 giengkhoan c thi cong be Song Hong, ngoaitr mot gieng hong (112-BT-1X) th 65%

so cac gieng eu co bieu hien kh t trungbnh en tot, co 15 gieng c tien hanh th


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va trong o co 6 gieng c coi la co phathien nhng khong thng mai (103-TH-1X, 115-A-1X, 117-STB-1X, 118-CVX-1X, 119-CH-1X, VGP112-BT-1X), ty le

phat hien la 25%. ang ke nhat la gieng103-TH-1X thuoc lo hp ong cua Total,a tien hanh th 4 khoang, 3 khoang chodong vi tong lu lng 5,87 trieu feet khoikh ngay (165.000 m3/ngay) va 123 thungcondensat/ngay (11,6m3/ngay).

Tnh hnh au t va ket qua hoat ongtm kiem tham do neu tren cho thay mc

o tai lieu va hoat ong TKTD (a chan,khoan) khong ong eu gia cac lo. Vungong lo 106 va lo 101 con cha c nghiencu, cac lo 107-110 chu yeu mi co tai lieukhao sat a chan khu vc, con vung ncnong di 10m nc va vung ca vnh, nico nhieu cau tao trien vong nhng van chac khoan tham do, vung ong lo 118-119

do nc sau tren 800 m nen con cha clu y thch ang.Mac du dien tch ngoai khi be Song

Hong la khu vc rat rong ln, con nhieub an ve tiem nang dau kh, song congtac TKTD noi chung ch c ay manht nhng nam 90, cha co nhng bc soiong nh them luc a pha Nam. e aymanh va nang cao hieu qua tham do beSong Hong can thiet phai au t nghiencu chnh xac cau truc a chat va he thongdau kh, ong thi phai nghien cu ap dungcac cong nghe mi (a chan, khoan) phuhp vi ieu kien a chat phc tap cua beSong Hong.

3. Cac yeu to cau truc va kien tao

Be Song Hong la mot be tram tch eTam c hnh thanh t mot a hao dang

keo tach (pull-apart) co hng tay bac -ong nam, c khong che hai canh bangcac t gay thuan trt bang ngang (Hnh7.3). S khi au hoat ong cua cac t gay

nay la do va cham cua mang An o vaomang Au-A vao thi ky Eocen-Oligocensm. Hoat ong trt bang trai va keo tachchnh la yeu to a ong lc chu yeu tao beSong Hong. Sau qua trnh nghch ao kientao trong Miocen gia-muon, be tram tchtiep tuc trai qua qua trnh sut lun nhiet choen ngay nay.

La mot be tram tch co lch s phat triena chat phc tap t Paleogen en nay, beSong Hong vi nhieu pha cang gian-nenep, nghch ao kien tao, nang len-ha xuong,bao mon-cat xen, uon vong do nhiet, kems thang giang mc nc bien, v the, theokhong gian va thi gian, cau truc a chatva moi trng tram ong khong ong nhat

ma bien oi t Bac vao Nam, t at lien rabien, t mong trc e Tam en tram tchhien ai. Cung v the, be Song Hong baogom nhieu n v cau truc khac nhau, ancha tiem nang dau kh khac nhau. Hnh7.4 cho thay co 12 n v cau truc, lan ltt phan Tay-Bac xuong phan trung tamen cuoi pha Nam cua be Song Hong. Tuy

nhien, can nhan manh rang, cach phan icau truc nay khong hoan toan nhat quantheo mot quan iem nao o, ma chu yeula da vao hnh thai cau truc hien ai coxet en tiem nang trien vong dau kh lienquan.

3.1. Trung ong Quan

ay la phan trung sau trong at lien

thuoc MVHN, c gii han vi phan raong Bac bi he t gay Song Lo ve pha


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ong Bac va vi i nghch ao kien taobi t gay Vnh Ninh ve pha Tay, va conkeo dai ra vung bien nong thuoc lo 102.ac iem noi bat cua cua i nay la cactram tch Miocen day 3.000m, uon vongnhng on nh, t hoat ong kien tao, vanam bat chnh hp len tram tch Eocen-Oligocen, day hn 4.000 m, a b nang len,

bao mon-cat xen cuoi thi ky Oligocen.Hoat ong kien tao nang len, kem vi viec

dch chuyen trai vao thi ky o a tao nenmot mat cat Oligocen co nhieu khoi-t gaythuan-xoay xeo (normal-tilted fault block).Cac khoi-t gay- xoay xeo nay la nhngbay dau kh quan trong, ma mot trong soo a c phat hien la mo kh D14 (Hnh7.5).

Hnh 7.3. Hnh thai cau truc Be Song Hong (theo OMV, 2001)


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Hnh 7.4. Ban o cau truc mong va cac i cau truc chnh be Song Hong(Theo N.M. Huyen, 1998, hieu chnh nam 2004)


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3.2. i nghch ao Miocen Tay Bac beSong Hong

Thc chat i nay trc o nam trongmot a hao sau, chieu sau mong sau tren 8km trong pham vi t at lien ra en lo 102,103, 107 nhng sau o b nghch ao trongthi ky t Miocen gia en cuoi Miocenmuon, vai ni nghch ao kien tao conhoat ong trong ca au thi ky Pliocen.i nghch ao nam kep gia t gay Song

Chay Tay Nam va t gay Vnh Ninh ong Bac, keo dai t at lien ra bien.Cac cau tao ac trng cho nghch ao kientao Miocen la cau tao Tien Hai (at lien),Hoa ao, Cay Quat, Hoang Long, BachLong... cac lo 102, 103, 106, 107. Hoatong nghch ao nay giam dan, tao thanhmui nho ong Sn keo dai en lo 108,

109. Nguon goc cua nghch ao kien taola do dch chuyen trt bang phai cua he

thong t gay Song Hong vao thi ky cuoiMiocen. V vay, mat cat tram tch Miocen

b nen ep, nang len, b bao mon cat xenmanh, mat tram tch t vai tram va co theen hang nghn met, thi gian thieu vangtram tch t mot en vai trieu nam. Cangve pha Tay - Nam cua MVHN, hien tngbao mon cat cut cang manh hn, do ayva co dch chuyen ngang va co hientng quay theo chieu kim ong ho. Tuy

ay la mot oi tng TKTD het sc quantrong, nhng do cau tao c hnh thanhmuon hn pha tao dau chnh va lai b baomon cat xen qua manh nen kha nang tchtu dau kh b han che. V the ay co thexem la rui ro th nhat cua cac bay dau khloai nay. Rui ro th hai lien quan en chatlng cha, v trc o, tram tch Miocen

a nam rat sau trong a hao (co) nen ata a tng b nen ep chat bi ap suat tnh,

Hnh 7.5. Mo kh Tien Hai-C trong i nghch ao kien tao Miocen (A) va mo kh D14 i trung ongQuan vi khoi-t gay- xoay xeo trong Oligocen (B) (theo Anzoil, 1996)


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cho du sau khi b nghch ao mat cat c

nang len nhng at a nay van gi o rongnguyen sinh thap co t trc, roi lai chuthem cac qua trnh bien oi th sinh neno rong lai cang kem i. Phng hng tmkiem tham do cho cac cau tao loai nay lachon cac cau tao bnh on ve mat kien tao,t b bao mon va co thi gian bao mon ngannhat trong Miocen (Hnh 7.6).

3.3. Trung Trung Tam be Song HongTrung Trung Tam la phan tram tch kha

bnh on ve mat kien tao, mong nam sauhn 14 km, nam ngay chnh gia vnh BacBo, chay theo hng tay bac - ong nam,trong pham vi rat rong t cac lo 108 en115. Tai tam bon trung (depocentre), thanhphan hat mn la chu yeu, co cac diapir set

phat trien va tren o cac tram tch Miocentren- Pliocen b nang vi bien o nho. Vao

cuoi Miocen au Pliocen, do anh hng

cua kien tao nghch ao phan Tay Bacvnh Bac Bo nh a noi tren nen tram

tch Pliocen b nang len chut t tao thanh

i nang ong Sn keo dai t lo 108 en

lo 111. Do hng o vat lieu t Tay Bac

xuong ong Nam va hng a v tuyen t

at lien ra bien, nen co nhieu than cat dang

non phong vat va cac tap turbidit co tuoi

Miocen muon - Pliocen sm. Cac oi tngtm kiem tham do Trung Trung Tam bao

gom: cau tao khep kn co bien o nho tren

i nang ong Sn (khu vc 108, 109, 110,

hnh 7.7) va cac cau tao khep kn bon chieu

phat trien tren cac diapir set (lo 110, 111,

113, hnh 7.8) nh cac phat hien Dong

Fang va Ledong cua Trung Quoc va cac

quat cat dang turbidit pha ong cac lo110, 111, 112 va 113, 115 (hnh 7.9).

Hnh 7.6. Phat hien kh va condensat trong cat ket Miocen tai gieng khoan 103-TH-1X (theo PIDC, 2004)


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3.4. Them Ha Long (Ha Long Shelf)Them Ha Long (co tac gia goi la i

ong Bac t gay Song Lo) pha ongBac t gay Song Lo phat trien t at lienra bien en cac lo 101 va Bac lo 106. Taiay co lp phu tram tch Kainozoi mongva mong Paleozoi nang cao dan roi lo trenmat at lien tai ra ong Bac MVHN.

Mot so gieng khoan nong trong i naya phat hien c cac a mong carbonat

(K.8, K.14, K.81, B10-1X) va a phien set-sericit, cat ket dang quarzit (B10-1X, B26-

1X, ) Paleozoi muon. Mong cua phan ra

noi dan len cao va lo ra nhieu ni nh o

Sn, Kien An, Vnh Ha Long (hnh 7.10)

vi cac thanh tao carbonat va luc nguyen

Paleozoi muon (Devon-Carbon-Permi).

Gii han ra ong Bac cua mong Paleozoi

la t gay ng 18 (Pha Lai - ongTrieu), o cung la ranh gii cua cau truc

Hnh 7.7. Cac cau tao khep kn co bien o nho, nhng co d thng bien o a chan manhco the lien quan en kh (theo PIDC, 1998)

D THNG BIN A CHN

Gn nc Pliocen

Trong Pliocen

y Pliocen

D THNG BIN A CHN

Gn nc Pliocen

Trong Pliocen

y Pliocen

Hnh 7.8. Mo hnh cau tao khep kn bon chieu phat trien tren cac diapir set lo 113 (a)va mat cat a chan thc te (b)

Diapir set

Gan noc Pliocen

Trong Plicen

ayPliocen

Diapir set

Gan noc Pliocen

Trong Plicen

ayPliocen

a b


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nen sau-Caledoni va trung Mesozoi. Lpphu tram tch Kainozoi khong qua 2000mtrong mot so a hao rat hep va mong dan

ve pha Bac, Tay Bac. Tren ban o a chat

Viet Nam, co the thay ay la mien mongn nghieng ma pho bien hn ca la a voiCarbon - Permi (he tang Bac Sn), a voi

va phien silic Devon gia - tren (he tang Lo

Hnh 7.9. Lat cat khu vc qua tam bon trung va cac quat cat/turbidit - lo 111(theo OMV, 2001)

Hnh 7.10. Cac ao a voi Vnh Ha Long va cac i nt ne trong a voi Paleozoi muon


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Sn) hoac cat ket a phien mau o va cuoiket Devon di (he tang o Sn). Doc theohe thong t gay Song Lo, canh ra themHa Long la mot a hao nho hep, trong o

co cac khoi mong nho cao nh Yen T -Ch Linh (la oi tng TKTD), ton tai cackhoi a voi tuoi Carbon-Permi c chonvui di tram tch Oligocen - Miocen, cont ne, co kha nang cha dau kh (giongnh Anzoil a phat hien B10, hnh 7.11).Cac oi tng tm kiem dau kh la a hnhvui lap carbonat, chiem mot dien tch nho

trong cac a hao nho hep (hnh 7.12) keodai t at lien ra goc ong-Nam lo 106 vagoc ong-Bac lo 102. Phan ln dien tchlo 101 thuoc them Ha Long la mot nnghieng cha c nghien cu.

3.5. i nghch ao Bach Long V

Mot a hao nho hep t gia lo 107 theohng ong bac - tay nam en goc ong

- Nam cua lo 106 va ven theo ra phaTay-Bac cua ao Bach Long V, chu anhhng cua hoat ong kien tao nghch aovao thi ky Oligocen muon - Miocen sm(Hnh 7.13, 7.14). Che o kien tao nay chxay ra vung giao nhau cua hai he thongt gay khac hng tay bac - ong nam vitay nam - ong bac. Cac cau tao ch c

phat trien trong tram tch Oligocen-Miocendi nam trong cac a hao hep vi nguonsinh nho. a hao nay la phan uoi cua beTay Loi Chau noi vi be Song Hong, ma be Tay Loi Chau Trung Quoc a phat hiendau trong tram tch vun Eocen.

3.6. Them n nghieng Thanh - Nghe(Thanh-Nghe Monocline)

Them n nghieng Thanh Nghe chaydoc theo ng b t ra Tay-Nam MVHN

qua cac lo 103, 104 xuong Bac lo 111. RaTay-Nam MVHN la phan nho cao cuamong ket tinh Proterozoi thuoc i cat trtSong Hong va cau truc Mesozoi Ninh Bnh

- Song a (Meso-Tethys Song a). MongTrc-Kainozoi khong ch la cac phc hebien chat ket tinh Proterozoi va pho bienhn con la cac thanh tao carbonat, carbonat-set va luc nguyen Mesozoi. Cac thanh taogneis Proterozoi va carbonat Mesozoi chiemv tr nho cao cua mat mong, con cac tramtch luc nguyen va set-voi Mesozoi thng

nam trong lom sau ma tren o cac tram tchKainozoi co the day ti 2.000m. Ve phaNam, nhn chung them n nghieng Thanh-Nghe co xu the nghieng o doc ra bien,gom nhieu loai a tram tch tuoi khac nhaut Paleozoi (Ordovic muon - Silur, Carbon-Permi) en Mesozoi (Trias, Creta) va cacthanh tao xam nhap granit-biotit, granit hai

mica co tuoi Paleozoi. Trong pham vi themco mot vai cau tao dang vui lap (nh QuaVai, Qua Tao, Qua Le lo 104, hnh 7.15)vi lp phu tram tch mong (500-1.000m) co tuoi t Miocen en hien ai. Dichan them co nay co mot vai bay a tangdang ke ap len mong (qua Chuoi lo 104,Te Giac lo 111, hnh 7.16) nhng vi tiem

nang khong ln do a cha co o rong nho.oi tng ang quan tam hn la cac baya tang cat ket co tuoi Oligocen-Miocensm.

3.7. Them a Nang (Da Nang Shelf)

Them a Nang la phan them nghieng tgoc pha Nam lo 111 chay doc theo ngb ve pha Nam ti them Phan Rang pha

Tay be Phu Khanh. Mong trc e Tamcua them c ac trng bi tram tch phan


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Hnh 7.11. Cau tao B10 ni phat hien dau trong mong Carbonat Permi nt ne (Anzoil, 1996)

Hnh 7.12. a hnh vui lap carbonat tai cau tao Yen T, lo 106 - mot oi tng cha dau mi (PIDC, 2004)

Tuyn 2590

Mng CarbonatMz

Trm tch Eocen?

Tuyn 2590

Mng CarbonatMz

Trm tch Eocen?


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Hnh 7.13. Tuyen GPGTR 83-07, lat cat khu vc qua trung tam, t them Thanh-Nghe (lo 103)qua ao Bach Long V (lo 107)

a ho nghch ocui Oligocen - Miocen sm

TN B

Thm Thanh Ngh_

Hngo Bch Long V


TN B

Thm Thanh Ngh_


TN B

Thm Thanh Ngh_

Hngo Bch Long V

Hnh 7.14. Lat cat qua cau tao PA trong i nghch ao Oligocen Bach Long V


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Hnh 7.16. Cau tao Te Giac (lo 111) nam ke ap len mong cua them Thanh - Nghe (theo Sceptre, 1992)

Hnh 7.15. Cau tao qua Vai (lo 104) tren them n nghieng Thanh - Nghe (theo OMV, 1999)


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lp co tuoi Paleozoi en Meozoi. Nhieuni, them c phu bang lp carbonat themco tuoi Miocen gia -muon, nh tai cautao Anh Vu, hay Hoang Anh, lo 112 (Hnh7.17). Nhn chung rat t cac cau tao co trienvong dau kh trong pham vi phat trien cuathem do lp phu tram tch Kainozoi mong.

3.8. Phu be Hue- a Nang

Phu be Hue - a Nang chu s chi phoi

cua cac he thong t gay Song Ca - Rao Nay- Hue trong pham vi cac lo 112 va 114. Vaocuoi Oligocen cac t gay ay la cac tgay trt bang trai, a tao nen cac cap ahao-a luy dang bac thang (en-echallon).Trong phu be nay quan trong nhat la a haoAnh Vu - a Nang va i nang Hai Yen -Bach Tr - Than Nong. Phan ln cac khoi

mong ay c nang len trc Oligocensm va tiep tuc c phat trien ong tram

tch trong Miocen sm. Mot oi ni, trongcac a hao hep, co hoat ong nghch aokien tao cuoi Oligocen-Miocen sm nh cau tao Voi lo 111 (hnh 7.18), cau taoKim Tc lo 114 (hnh 7.19). Tren cac inang la cac cau tao phat trien ke tha trenmong a voi tuoi Devon gia-muon co khanang cha dau kh nh cac cau tao HaiYen, Bach Tr (Hnh 7.20). Ngoai ra trongphu be Hue-a Nang con co nhieu cau taokhep kn bon chieu trong tram tch Miocen(cau tao ai Bang, lo 112 (hnh 7.21) vamot vai cau tao am tieu carbonat nho.

3.9. i nang Tri Ton

i nang Tri Ton la i nho cao cuamong pha Nam be Song Hong, ma treno co lp phu la tram tch vun Oligocen, a

voi nen (platform carbonate) va khoi xaycarbonat - am tieu san ho (carbonate build-

Hnh 7.17. Cau tao Anh Vu va Hoang Anh (lo 112) tren them n nghieng a Nang


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Hnh 7.19. Cau tao Kim Tc (lo 114), nghch ao trong Miocen sm, phu be Hue - a Nang(theo Shell,1990)

Hnh 7.18. Cau tao Voi (lo 111), phu be Hue-a Nang


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Hnh 7.20. Cau tao Bach Tr, mong a voi Devon, lo 112, phu be Hue - a Nang (theo PIDC,1998)

Hnh 7.21. Cau tao ai Bang, lo 112, phu be Hue - a Nang (theo Shell, 1993)


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ups/reefal carbonate) tuoi Miocen gia

- muon. Theo cac ket qua nghien cu cua

Nguyen Manh Huyen nam 1998 va mi

ay nam 2002 i nay co chieu dai khoang

hn 500 km, phan phat trien rong nhat va

cao nhat la lo 121-120, sau khi qua caclo 119-118-117 (Hnh 7.22) th nho dan va

chm dan ve pha lo 113. Thc te, khi lien

ket va tong hp cac tai lieu a chan vung

lo 115, lo 113, ong lo 111, tai lieu ke

can cua Trung Quoc va ac biet la tai lieu

trong lc ve tinh cho thay i nang Tri Ton

khong dng lai pha Nam lo 115 nh motso cong bo trc ay, ma thc te con phat

Hnh 7.22. Cau tao carbonat Ca Voi Xanh, lo 118, i nang Tri Ton (theo BP, 1992)

Hnh 7.23. Cau tao C (carbonat), lo 113 (theo PVSC, 1998)

BB95-0535

BB95

-0515

BB95

-0610

BB95

-0725

0 5 1 0

km

BB95

-0620

BB95-5450A

BB95-5495

BB95-5520

Prospect 113B

Prospect 113C

Prospect 113D

Prospect 113A

Prospect 111A

LD14-1-18LD14-1-1

LD15-1-2

LD21-1-1

LD20-1-1 LD 20-1-2

1080 10'E 1080 20' E 1080 30' E 1080 40'E

1080 10' E 1080 20' E 1080 30' E 1080 40'E

170 30'E

170 20'E

170 10'E

170 00'E115114

113

111 UPPER PLIOCENE

LOWER MIOCENE

DRILLEDWELL (CNOC)

TURBIDITESZONE


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trien tiep tuc kha ro en lo 113 (qua cau tao

113 C, 113 D, hnh 7.23), tham ch co the

con ton tai anh hng cua carbonat ong

lo 111 va tiep tuc ven ra ong lo 110. Pha

ong cac lo 113, 111, 110 i nang nay

phat trien ke can mot them doc hien ai cotuoi Pliocen - e T, nghieng t them Dinh

c (ao Hai Nam) ra tam be (co cau truc

tng t nh pha ong cac lo 120 - 121

pha Nam). Do phan nay cua i nang nam

o sau ln vi moi trng bien sau (trong

qua kh), nen tram tch carbonat khong con

day, hn the na tren i nang b phu mot

lp set Pliocen - e T qua day (khoanghn 2000 m) nen viec quan sat no tren mat

cat a chan se kho khan hn nhieu so vi

vung pha Nam.

Mot loat cac phat hien kh tren cac cau

tao khoi xay carbonat/san ho am tieu i

nang Tri Ton cho thay cac tang cha co chat

lng rat tot vi o rong trung bnh 20-30%

nh a thay cac gieng khoan 115-A-1X,118-STB-1X, 118-CVX-1X, 119-CH-1X.

3.10. a hao Quang Ngai

a hao Quang Ngai la mot a haohep, la phan uoi pha Nam cua be SongHong, nam kep gia them a Nang va inang Tri Ton t lo 116 en lo 121 va thong

vi be nc sau Phu Khanh pha Nam.Tram tch trong a hao co the day en 8-9km, bao gom tram tch t Eocen en hienai. ac biet pha phun trao cuoi Miocen- Pliocen hoat ong manh tai ay, nhat laphan pha Tay lo 120. a hao nay co cautruc n gian vi hnh cat ngang nh motlom sau oan vong. Trong o khong co nhng

cau tao khep kn 3 hoac 4 chieu, nhng conhieu quat cat tuoi Miocen co chat lngcha tot (hnh 7.24). a hao Quang Ngaila mot trong nhng khu vc sinh chnh cuaphan pha Nam be Song Hong.

3.11. a hao Ly Sn

a hao Ly Sn (cach ay khong xala ao Ly Sn, huyen Ly Sn, tnh Quang

Ngai) nam pha ong i nang Tri Ton,chu yeu trong pham vi pha ong cac lo

Hnh 7.24. Quat cat bay a tang, cau tao Bach Tuoc trong a hao Quang Ngai, lo 118 (theo BP, 1995)

118-BT-1X118-BT-1X


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117-118 va pha Tay cac lo 141-142, conpha Nam va ong Nam tiep giap vi inang Hoang Sa. a hao Ly Sn con co

nhieu ten khac, co tac gia goi la Trung TriTon hoac a hao ong Tri Ton, con congty BP a co luc goi no la i Rift ong-Bac (NE Rift Province-NERP). Tram tchla cac manh vun lap ay cac a hao va bana hao hnh thanh trong thi ky tao RiftEocen-Oligocen. Hien tai i nay nam ratsau di mc nc bien t 500 en 1.500

m. Ve cau truc a hao Ly Sn phan bo theohng tay nam - ong bac (nh hng cautruc cua i nang Trng Sa). Co the trongcac a hao nay nguon a me am ho se rattot, nhng hien tai cha c nghien cuva ac biet trong i nay co rat nhieu cautao trien vong nh Ca Chuon, Ca Lang, Raica, Ca ao, Ca Nga... (Hnh 7.25). Nam

1996, Cong ty BP a bo sung vao ay mangli a chan u day, phat hien c nhieu

cau tao trien vong hoan chnh, nhng domc nc sau nen cha co ieu kien khoantham do.

3.12. Them n nghieng Tay Hai Nam

Nam b pha ong Vnh Bac Bo,chay doc pha Tay ao Hai Nam la Themn nghieng Tay Hai Nam (con goi la themDinh C). Them nghieng thoai t ao HaiNam roi o doc ve pha Tay vao trung tambe Song Hong. a mong tao them cung bao

gom cac loai tram tch Paleozoi - Mesozoi(gan giong vi them Thanh - Nghe) va lpphu tram tch chu yeu la Miocen - e Tmong di 1.000 m, nam trong lanh haiTrung Quoc.

4. a tang, tram tch va moi trng

a tang cua be Song Hong tng oi

phc tap bao gom mong trc e Tam,tram tch Paleogen, tram tch Neogen va

Hnh 7.25. Cau tao Ca Lang trong a hao Ly Sn, lo 118 (theo BP, 1994)


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tram tch Pliocen - e T a c nghiencu chi tiet trong chng 6. Bi vay, trongchng nay se ch neu khai quat nhng net

chnh vi muc tieu nghien cu anh gia tiem

nang dau kh. Hnh 7.26 la cot a tang tong

hp be Song Hong mot cach khai quat tpha Bac (ben trai cot a tang) xuong pha

Nam (ben phai cot a tang). Tren o cho

thay mong, lp phu, thanh phan thach hocva moi trng tram ong cua chung bien

oi t Bac vao Nam. ong thi, mot cachtng oi, con cho thay cac bat chnh hp

chnh ong vai tro quan trong, mc o bao

mon, s thieu vang tram tch va he thong

dau kh trong thang a tang o.

4.1. Mong trc e Tam

Mong trc e Tam khu vc MVHN

va lan can lo ra kha a dang tai cac ira ngoai va phan thanh nhieu i thanh he

Hnh 7.26. Cot a tang khai quat t Bac vao Nam Be Song Hong( N.M.Huyen 1998, hieu chnh & bo sung nam 2004)


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- cau truc khac nhau. Ngay gia trung tamMVHN a phat hien c mong Mesozoitai gieng khoan 104 (3.941m-TD) chu yeugom: ryolit va tuf Mesozoi. Tai ra Tay

- Nam MVHN a mong co nhat gom caca bien chat ket tinh gneis, phien biotit-amphybol Proterozoi gap trong cac giengkhoan 15 (Nam nh), 57 (Hai Hau)... Conra ong-Bac (khu vc cac gieng khoanB10-1X, B10-2X, B26-1X...) a gap mongla cac thanh tao carbonat, phien set-sericit,cat ket bien d tuoi Paleozoi muon tng

bien nong: a voi Carbon - Permi cua hetang Bac Sn, a voi va a phien silicDevon gia-tren he tang Lo Sn, cat ketphien set mau o xen cuoi ket Devon dicua he tang o Sn (Devon - PZ).

Trong khi o, doc them luc a mienTrung, mong trc e Tam pho bien nhatla cac loai tram tch Ordovic tren - Silur

thuoc he tang Long ai va Song Ca baogom a voi, cuoi san ket, a phien. Ngoaira con co cat ket, cuoi ket Devon di thuoche tang Tan Lam, a voi Devon gia - trenthuoc he tang Cu Bai, cac a xam nhapgranit-biotit... Cac he tang nay co xu thephat trien ra bien va co the tao nen nhnga hnh vui lap e tr thanh cac bay dau

kh quan trong nh a c phat hien taicau tao Bach Tr lo 112.

Pha Nam be Song Hong, ngoai trgieng khoan 115-A-1X a bat gap mongbien chat Mesozoi, con tat ca cac giengkhoan con lai eu cha gap mong trc eTam. Tuy vay qua cac tai lieu hien co, cothe d oan mong khu vc nay cung la cac

a carbonat Mesozoi, a bien chat va t hnla magma xam nhap.

4.2. Tram tch Paleogen

4.2.1. Tram tch Eocen

Tai vung Tay - Bac be Song Hong

(hnh 7.27). Tram tch Eocen (he tang PhuTien) c phat hien gieng khoan 104thuoc MVHN gom cac tap cat ket hat thomau o xen ke vi cuoi ket va cat ket dangkhoi. Cac thanh tao vun tho mau o ayEocen nam trc tiep tren lp set phong hoacung mau phu tren tap phun trao ryolit cuamong. Theo tai lieu a chan, chieu daycua he tang thay oi t 100m-700m. Moitrng thanh tao chu yeu la luc a. Cacgieng khoan ngoai bien cha khoan ti hetang nay, nhng co the d oan qua lienket tai lieu a chan, chung la phan nam satmong trong cac a hao cua i cau truc (4)Them Ha Long sat ngay vi be Song Hongve pha ong Bac. Cac tram tch Paleocen- Eocen (he tang Chang Liu, TQ) a c

phat hien nhieu be Tay Loi Chau (TQ).Con ngoai khi be Song Hong noi chung,cha co gieng khoan nao khoan en tramtch Eocen, nhng nhn vao lat cat a chanco the d oan rang tram tch Eocen co mat nhieu ni, day vai ba tram met phan rava co the ti hang nghn met phan trungsau.

4.2.2. Tram tch OligocenCac thanh tao Oligocen (he tang nh

Cao, hnh 7.27) thng phan bo di o sau2000 - 3000 m va c phat hien trong nhieugieng khoan sau Trung tam MVHN. Nam2002, PIDC khoan gieng khoan PV-XT-1X thuoc phan ra Tay-Nam cung a phathien c tram tch cha bao t phan xac

nh tuoi Oligocen. Tram tch Oligocen chuyeu la cat ket, bot ket xen set phan phien...


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Tram tch Eocen tren - Oligocen di (PhuTien/Linshagang TQ) con co the pho bien khu vc lo 106, bao gom cac lp set mnmau en xen cat ket hat mn en tho nh a

gap gieng khoan 107-PA-1X. Moi trngthanh tao chung la am ho, song ngoi. Hetang nay co cha nhng tap set am ho dayco kha nang sinh dau tot.

Ve pha Nam be Song Hong (hnh 7.28),tram tch Oligocen (he tang Bach Tr), chuyeu c thanh tao trong cac trung sau cuakhu vc. Thanh phan chu yeu bot ket xen

cac lp set ket va cat ket hat nho en vaphat trien xuong pha Nam, lo 114 (GK114-KT) he tang co thanh phan cat ketnhieu hn va xen cac lp set ket, ca bietco cho xen kep nhng va than mong (GK118-CVX).

4.3. Tram tch Neogen (Miocen)

Tram tch Neogen phan bo rong rai

be Song Hong vi moi trng t ong bangchau tho, ven b ti bien nong va bien sau.Chieu day cua tram tch Neogen thay oi t500m cac i ven b en 4.000m trungtam vnh Bac Bo. Ngoai tr phan b nghchao i Tay - Bac, hau het cac tap euphat trien bnh on, uon vong, chu tac ongcua viec m rong Bien ong.

mien vong Ha Noi va phan Tay-Bacbe Song Hong cac tram tch Miocen cchia thanh 3 he tang: Phong Chau (Miocendi), Phu C (Miocen gia) va Tien Hng(Miocen tren). pha Nam cua be cac tramtch Miocen c chia ra cac he tang SongHng (Miocen di), Tri Ton (Miocengia) va Quang Ngai (Miocen tren).

Tram tch Miocen diTram tch Miocen di (he tang Phong

Chau) phan bo chu yeu trong dai KhoaiChau - Tien Hai (GK. 100) va phat trienra vnh Bac Bo (GK 103-TH) vi s xenke gia cac lp cat ket hat mn, cat bot ket

va set ket cha dau vet than hoac nhnglp kep a voi mong (GK 103-TH, 103-HOL). Moi trng bien ven b, chau tho,bien nong. Ve pha Nam be Song Hong, tlo 117-121, tram tch Miocen cang co aciem khac han so vi vung Tay - Bac cuabe. Tram tch Miocen di (he tang SongHng) co thanh phan thach hoc chu yeu

la tram tch hat mn lang ong trong moitrng bien, con tren i nang Tri Ton abat gap a voi dolomit phan tren cua atang (lo 120-121), va con co mat cac axam nhap nui la trong va ngay canh ahao Quang Ngai nh GK 121-CM-1X.

Tram tch Miocen gia

Tram tch Miocen gia (he tang Phu C)

phat trien rong khap trong mien vong HaNoi, co be day mong vung ong Quan vaphat trien ra vnh Bac Bo vi thanh phantram tch gom cat ket, set bot ket, than vaoi ni gap cac lp mong carbonat (GK 103TH-1X, GK 107-PA-1X), moi trng biennong xen ke vi chau tho. Ve pha Nam,tram tch Miocen gia co ac iem khacvi vung Tay Bac nen c goi la he tangTri Ton. Tram tch he tang nay co mat cac a hao nam hai ben a luy Tri Ton:a hao Quang Ngai va a hao Ly Sn vala cac tram tch hat mn thanh tao trong moitrng bien sau; con tren a luy Tri Tonc phu mot lp a carbonat day en vaitram met, pha di la dolomit, trong khiphan tren la a voi. Tren them a voi nay

phat trien kha rong rai cac am tieu sinh vat,la oi tng cha co chat lng rat tot a


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gap nhieu gieng khoan trong vung.

Tram tch Miocen tren

Tram tch Miocen tren (he tang TienHng) co mat trong hau het cac gieng

khoan mien vong Ha Noi va ngoai khi

vnh Bac Bo vi thanh phan chu yeu la cat

ket, phan tren thng la cat ket hat tho

va san soi ket, set ket, bot ket, xen cac va

than. Mc o cha than giam i ro ret do

tram tch tam giac chau ngap nc, vi tnh

Hnh 7.27. Cot a tang MVHN va phan Tay-Bac Be Song Hong (PIDC, nam 2004)


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bien tang theo hng tien ra vnh Bac Bo.

Moi trng chu yeu la bien ven b, biennong xen chau tho. Mot iem ang chu y la

tai Trung Trung Tam be Song Hong, phan

tren (hoac hau het) cua mat cat Miocentren eu la moi trng nc nong en sau.

Hnh 7.28. a tang pha Nam Be Song Hong (PIDC, 2004)


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phan pha Nam cua be, tram tch Miocen

tren (he tang Quang Ngai) chu yeu la set,

set ket bien va cha mot so lp a voi mong

moi trng chu yeu la bien sau. Cang ve

pha Tay (them a Nang) tram tch co hattho dan va xen ke nhieu the phun trao.

4.4. Tram tch Pliocen - e T

Tram tch co tuoi Pliocen - e T

MVHN gom cac he tang Vnh Bao-Hai

Dng-Kien Xng. Chung nam tren mat

bat chnh hp cuoi Miocen, on nh va m

rong en cac i ra cua MVHN. S phanbo cua cac tap tram tch Pliocen (he tang

Vnh Bao) kha on nh, vi xu the day dan

ra pha bien. ay la thi ky san bang a

hnh, ngap lut mi sau pha nghch ao kien

tao cuoi Miocen. Xu the nay c tiep tuc

cho ti e T vi cac thanh tao thuoc he

tang Hai Dng va Kien Xng.

Cang ra bien, tram tch Pliocen-e T

(he tang Bien ong) cang day len, nhng

van co dang b ri, gan ket yeu. Rieng

phan Trung Trung Tam be Song Hong ni

tram tch Pliocen at en chieu sau t 2.000

- 3.000m la oi tng quan trong e tm

kiem dau kh. Thanh phan thach hoc chu

yeu la cat san soi gan ket yeu xen ke setmau xam, thanh phan hat mn ton tai Trung

Trung Tam chu yeu la set. Moi trng tram

tch la bien nong en bien sau.

Ve pha Nam be Song Hong, he tang

Bien ong chu yeu la set, set ket xen ke

nhng lp mong bot va cat. Cang gan b,

tram tch tho dan va co mat cac a phun

trao. Moi trng tram tch la bien t nongen sau.

5. Cac tch tu hydrocarbon

a co rat nhieu nghien cu cong bove cac iem lo co dau hieu dau kh trenat lien (xem chng 2 va 15). ac biet tai

ong Ho, tat ca cac nghien cu eu chothay cac vet dau sinh ra tai ay eu conguon goc t a me la set than va set amho co tuoi Oligocen.

Cac dau hieu va cac phat hien dau khcon c khang nh qua tai lieu giengkhoan tai MVHN: a phat hien 2 mo khnho TH.C va D14 ngoai ra co t nhat hn

chuc gieng khoan tham do a co bieu hiendau kh t tot en rat tot. Trong tong so 24gieng TKTD a khoan ngoai khi be SongHong th co 11 gieng co dau hieu dau kh,trong o co 6 phat hien chiem 25 %. Sau ayla tom tat mot so phat hien chnh ca trongat lien va ngoai khi be Song Hong.

Tai MVHN, phat hien kh Tien Hai C

vao nam 1975 tuy nho, vi tr lng khtai cho ch khoang hn 35 Bcf (1 ty m3),nhng lai anh mot dau moc vo cung quantrong trong lch s tham do dau kh mienBac Viet Nam - ay cung la phat hien autien trong dang bay nghch ao kien taoMiocen, mo c a vao khai thac chnhthc t nam 1981 va ang cung cap kh chocong nghiep a phng cua tnh Thai Bnh.Phat hien kh th hai lien quan en cautao nghch ao Miocen la lo 103, ngoaikhi vnh Bac Bo. Nam 1990 Cong ty Totalkhoan gieng 103-TH-1X va dng chieusau 3.413 m trong mat cat Miocen di, aphat hien t 3 va vi tong lu lng 5,87MMcfd (165.000 m3/ngay) va gan 125 barelcondensat/ngay (9,9 m3/ngay). Tr lng

kh tai cho bc au tnh c khoang 247Bcf (7 ty m3).


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Nam 1996 Cong ty Anzoil a phat hienkh tren cau tao Song Tra Ly (D14-STL).Cau tao STL chnh la cau tao ong Hoangtrc ay a c Petrovietnam phat hien

vao nam 1975 bang tai lieu trong lc vanam 1976 bang tai lieu a chan. Cau taoco dang vom-khoi t gay xoay xeo (tiltedfault block) trong tram tch Oligocen. Giengkhoan au tien cua Anzoil, D14-STL-1Xkhoan nam 1996 at o sau 3.354,7 m, ac th 3 va th 2 va cho dong vi tonglu lng 5, 25 trieu feet khoi kh/ngay

(148.000 m3/ngay) trong tang cha la catket song ngoi Oligocen (hnh 7.29). Trenc s ket qua cac gieng khoan tham lngnam 2000, Anzoil a cung Cong ty Quocte Gaffney Cline&Associates (GCA) anhgia lai tr lng D14, ch tnh rieng vomBac la ni a co phat hien thc s e tnhtoan, xay dng e an tien kha thi. Theo tnh

toan nay, kh tai cho D14 dao ong t 25Bcf (Min) en 1,7 Tcf (Max) tc xap xy 0,8

en 48,5 ty m3 kh, trung bnh la 133 Bcf(3,7 ty m3). Hien mo ang c th va daihan e thu thap cac thong so lap ke hoachkhai thac.

Cung nam 1996, Anzoil phat hien dautai cau tao Song Thai Bnh (B10-STB).Cau tao Song Thai Bnh la cau tao chonvui (Burried Hill) carbonat au tien co chadau c phat hien MVHN. Gieng khoanB10-STB-1X dng lai chieu sau 1.450 msau khi xuyen qua 35m a voi va 90 m catbot ket xen ke ran chac tuoi Carbon-Permi

(hnh 7.30). Gieng a cho dong 164 barel/ngay (25 m3/ngay) khi x ly va bang axitva 227 barel/ngay (36 m3/ngay) khi co sho tr cua bm hut trong gieng khoan. Dogieng khoan ch gap 12 m cha dau tronglp a voi tren cung, tr lng nho cungvi tnh chat tham cha kem cua va, phathien B10 v vay cha c xem la thng

mai. Tuy nhien, phat hien nay m ra mothng mi cho viec tm dau vung ong-

Hnh 7.29. Tang cha cat ket Oligocen, giengkhoan D14-STL-1X

Hnh 7.30. Tang cha a voi mong nt ne, trce Tam gieng khoan B10-STB-1X


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Bac MVHN khu vc phan Tay Bac ngoaikhi be Song Hong.

Tai cac lo pha Nam, cac cong ty IPL,BP a phat hien nhieu mo kh cha trong

a carbonat tren i nang Tri Ton: giengkhoan 115-A-1X (lo 115), gieng khoan117-STB-1X (lo 117), gieng khoan 119-CH-1X (lo 119); gieng khoan 118-CVX-1X(lo 118). ay la cac mo kh khong lo, tuynhien cac phat hien nay co thanh phan CO2rat cao, nen cha the phat trien c.

Kh hydrocarbon tai cac phat hien pha

Nam be Song Hong eu co thanh phan vanguon goc kha giong nhau. Cac kh nayeu b lan kh CO2, vi ham lng cao (lnhn 75%). Nguon goc cua CO2 co the sinhra do qua trnh bien oi carbonat bi nhiet(do chon vui sau, b hun nong bi hoat ongmagma) hoac t vo manti (manlte) i lentheo cac t gay sau. Ngoai CO2 con co

mat cac kh N2, O2 va H2S. Bang 7.1 ch ranhng hp phan chnh cua cac phat hienkh cac gieng khoan pha Nam be SongHong.

Bang 7.1. Mot so ac iem thanh phan kh cacgieng khoan Nam be Song Hong

Thanhphan

115-A-1X

117-STB-

1X

118-CVX-

1X

118-BT-1X

119-CH-1X

C1

-C6(%) 6 15 21.15 88.77 88.76

CO2(%) 90 85 75.03 2.69 3.53

N2(%) 4 - 3.82 8.54 7.5

O2(%) - - - - 0.21

H2S(ppm) 250 1500 450 -

200-1700

Pha b ong be Song Hong, trong

nhng nam 1990-1996, Trung Quoc a aymanh cong tac TKTD va a phat hien ra cac

mo kh thng mai ln. Cach lo 113 khongxa la mo Yangchen do Arco phat hien vitr lng khoang 3 Tcf (86 ty m3) trong catket Oligocen, mo nay ang c khai thac.

Nam ngay canh lo 109 la mo Dong Fangdo CNOOC phat hien, tang cha la cat ketPliocen o sau 1.500-2.000 m, tr lngkhoang 2,5 Tcf (70,8 ty m3), ham lng CO2thap - trung bnh.

6. He thong dau kh

6.1. a sinh

Trong pham vi be Song Hong a xacminh c hai tang sinh quan trong la ame Oligocen va Miocen di. Thanh phankerogen cua cac tang a me nay thngkhong giong nhau cac i cau truc khacnhau trong be. Con a me Eocen mi chc chng minh trong he tang Chang-liutai be tram tch Tay Loi Chau canh be SongHong. Tang sinh Eocen c phat hien taibe Tay Loi-chau, trong cac tap a set giauvat chat hu c vi tong ham lng cacbonhu co (TOC) khoang 2,67-2, 78%Wt,ham lng va ch so hydrogen ln (S1+S2khoang 10-30 mg/g; HI khoang 200 - 600mg HC/g TOC), kerogen thuoc loai I va II.

Phan tch tang sinh tai vung Tay - Bac

be Song Hong noi chung va MVHN tren atlien noi rieng cho thay tram tch Oligocenthng cha kerogen loai III va t hn laloai II, thng b chon vui sau, nhng ame tai ay rat giau vat chat hu c, viTOC khoang 6, 9-11% Wt, HI t vai chucen hang tram mg HC/g TOC va ang trong pha tao kh am ti kh kho vi gia tr

Tmax khoang 430 - 480OC (Hnh 7.31, 7.32va 7.33). Tuy vay, tai ra ong Bac MVHN


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khi khao sat vung ong Ho va phan saucua ao Bach Long V a phat hien cac ame la set va set than trong cac tap Oligocenco kerogen ca loai I va II co kha nang sinhca dau va kh. Cac a me nay cung rat giauvat chat hu c (TOC = 7-18% Wt), S2khoang 21 - 41mg/g va co ch so hydrogencao (HI = 200 - 600 mg HC/g TOC), nhngo phan xa vitrinit trung bnh Ro = 0, 45(Tmax = 428-439OC), ang bc vao giaioan trng thanh (Hnh 7.34).

Tang sinh Miocen di tai MVHN va

vnh Bac Bo chu yeu la cac tap set, set-than sinh thanh trong cac pha ngap lutchnh cua cac tram tch chau tho. Phan lncac ket qua phan tch cho thay a me cokerogen loai III la chnh, ch mot so mau Bach Long V co bieu hien loai II. Ketqua phan tch mau thu thap trong cac giengkhoan tai cac lo 102, 103, 104, 112, 114 cho

thay gia tr tong carbon hu c t trung bnhen rat giau (TOC = 0,45-18%), song ch so

hydrogen thap (HI di 200 mg C/g TOC)ngoai tr phan ao noi Bach Long V vigia tr cao (HI ln hn 300 mg C/g TOC).Cac tang sinh Miocen thuoc khu vc ngoai

khi be Song Hong ang trong ngngtrng thanh en trng thanh sm va cokha nang cho san pham.

Tai khu vc mien Trung t lo 111 enlo 114 cha co nhieu cong trnh nghien cua hoa, nhng cac ket qua phan tch maucua gieng khoan 114-KT-1X cho thay trongcac a hao ay co tang a me Miocen

di co chat lng rat tot, nhng mi chmtrng thanh, con mat cat Oligocen rat daynhng a bc qua pha tao kh kho.

pha Nam be Song Hong, nhieu dauvet dau a c tm thay trong cac mau loiva mau sn lay t a voi Miocen cacgieng khoan 118-CVX-1X va 119-CH-1X.Cac tang a me quan trong nhat co the la

cac tang set am ho Eocen-Oligocen va setbien Miocen di thuoc cac a hao QuangNgai va a hao Ly Sn. Mac du vay, docha co mot gieng khoan nao trong khu vctm c cac tang a me thc s nen canquan tam nhieu trong thi gian ti (ch duynhat gieng khoan 118-BT-1X khoan tronga hao Quang Ngai, tuy nhien gieng adng o sau 3800m, trong Miocen sm-gia?). Cac a set t Miocen gia en trehn hau nh cha co kha nang sinh. Cactap set Oligocen, vi chieu day 25-30mgap tai gieng khoan 118-CVX-1X rat giauvat chat hu c vi TOC t 2-6% Wt, S2t 20-30 kg/tan va HI khoang 440 kgHC/tan TOC, thuoc loai a me sinh dau.Tuy nhien rat co the a me Oligocen a

bc vao giai oan trng thanh muon vach con sinh kh. Phan tch thanh phan kh

0

200

400

600

800

1000

1200

400 420 440 460 480 500

GK-PV-DQD-1X (Mn khoan 1630-3450m)PV-XT-1X (Mn khoan 700-1845m)

GK-63 (Li khoan 1151-2390m)

Type IType II

Type III

0.55%Ro

1.3%Ro

Nhit Tmax (oC)

Chs

Hydrogen

(mgHC/g

.TOC)

0

200

400

600

800

1000

1200

400 420 440 460 480 500

GK-PV-DQD-1X (Mn khoan 1630-3450m)PV-XT-1X (Mn khoan 700-1845m)

GK-63 (Li khoan 1151-2390m)

Type IType II

Type III

0.55%Ro

1.3%Ro

Nhit Tmax (oC)

Chs

Hydrogen

(mgHC/g

.TOC)

Hnh 7.31. o th bieu dien quan he HI - TmaxVung ong Nam dai Khoai chan-Tien Hai MVHN


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Hnh 7.32. S o trng thanh tai noc Oligocen/ay Miocen di, MVHN va ke can (theo PIDC, 2002)

I

II

Chu giaiTrng thanh

Ca so tao dau

Kh am - Condensate

0 5Km

VII

VIII

IX

GK104

GK116PV-PC-1X

GK112

GK11

GK100

GK77GK103

GK105

GK101

GK204

GK69GK83

GK200

D14-STL-2X

D14-STL-3X

D23-1XD23-2X

D14-STL-5X

GK20GK81

B10-STB-1XB10-STB-2X

V

XI

X

GK67III

IV

VIGK82

GK60GK84 GK102

GK110

GK41

Hnh 7.33. Mo hnh trng thanh tuyen GPGT 93-201 qua lo 103-106 (theo N.T.Ha, nam 2004.)

2Km

4Km

6Km

8Km

SP3500 SP3000 SP2500 SP2000 SP1500 SP1000 SP500

10Km

103TH-1X 103TG-1XGPGT 93-201


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thu c trong cac gieng 118-CVX-1X va119-CH-1X cho thay chung co nguon goct cac a me trc o a tng sinh dau. ame Miocen di ngheo vat chat hu c hn,TOC dao ong t 0.5-1% Wt. Cac i sinh cac a hao Quang Ngai va Ly Sn hiennay eu nam trong ngng sinh kh (Hnh7.35, 7.36, 7.37).

Nhn chung do tram tch be Song Hongb chon vui rat sau, a nhiet cao (khoang3.7-4.5OC/100m) nen hien tai a meEocen-Oligocen la cac tang a me chnh

noi chung a trai qua tat ca cac pha tao sanpham t dau en kh am, condensat va khkho. Trong o pha tao dau chnh a xay racach ay khoang 30-18 trieu nam, tao kham va condensat cach ay 20-8 trieu namva tao kh kho cach ay 10-5 trieu nam.Trong khi o, tram tch Miocen ma chuyeu la Miocen di neu b chon vui sau a

trng thanh, thng co pha tao dau chnhcach ay khoang 15-8 trieu nam, tao kh

am va condensat cach ay 10-5 trieu namva tao kh kho t khoang 7 trieu nam nay.Do vay, khi anh gia la chon mot cau taotrien vong can lu y nhng iem sau ay:

thi iem hien tai, tram tch angtrong pha tao kh kho la chu yeu, dientch co a me trong ca so sinh dau rathan hep. Cac cau tao hnh thanh trchoac ong tram tch Miocen sm - giaco the tch tu mot lng ln dau kh.Nhng neu b bao mon cat cut manhsau o hoac thieu tram tch cua lp

phu chan th cau tao o rat kho lu gidau, ma ch co the la mot tch tu kh vacondensat.

Cac cau tao phat trien muon trongMiocen- Pliocen ch co the on nhan vatch tu kh, trng hp thuan li nhat lakh condensat.

Cac cau tao hnh thanh trc va ong

tram tch Oligocen co the on nhan vatch tu dau, nhng v tr cua no phaithuan li: nam canh cac graben khongsau lam, on nh trong qua trnh phattrien be, khong hoac t b bao mon, tpha huy cua kien tao sau o.

6.2. a Cha

Cac a cha cua MVHN kha a dang

trong o co cat ket Oligocen, Miocen vacarbonat Miocen. Cac a co tiem nangcha trong mong Trc-Kainozoi bao goma carbonat Paleozoi va Mesozoi, a gneis.Trong so nay, a cha carbonat Paleozoint ne va hang hoc a c phat hien trongnhieu gieng khoan thuoc ra ong-Bac nhcac gieng khoan 8b, gieng khoan 81... va

ac biet la gieng khoan B10-STB-1X codau trong khoang o sau 1.225 - 1.237m

Hnh 7.34. Quan he ch so HI va Tmax trong tramtch cha than va a phien dau ong Ho va Bach

Long V (theo Petersen H.I. va nnk, 2000)


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vi o rong khoang 5-10% (Hnh 7.38). S

phan bo cua tang cha nay kha phc tap

vi o day khong on nh trong cac mat cat

a tang Paleozoi ra ong-Bac MVHN.Tren ra Tay - Nam, thanh phan la cac a

gneis Proterozoi a lo tren be mat mot

so ni nhng khong co bieu hien dau kh.

Nhn chung cac a cha trong mong Trc-

Kainozoi cua MVHN co nhieu rui ro ve orong va phan bo khong on nh. o rong th

Hnh 7.35. Mo hnh trng thanh tai lo 112 (PIDC, 2002)

0 Km

2 Km

4 Km

6 Km

112-AV-1X 112-BT-1X113-HO-1X

Mo hnh o trng thanh s kien 5

(10 trieu nam ve trc)

Thang ng gap 4 lan ngang

10 Km

Hnh 7.36. Mo hnh chon vui a me Miocen, tai GK-118-BT-1X, a hao Quang Ngai (theo BP, 1995)


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sinh cua chung phu thuoc vao cac i bien

oi va pha huy a goc. Nhn chung, oi vitang cha la a mong ch co the hy vongvao a voi Carbon-Permi va Devon gia-tren vi o rong trung bnh 5-7%. Cac among tram tch khac phan ln a b phonghoa bien chat, co o rong, o tham kem.

Tai MVHN, a cat ket thng phan lp-khoi day, b cac t gay chia cat va uon nep,

co tiem nang cha vao loai trung bnh enkem va a c mot so gieng khoan phathien co cac san pham kh va condensat.Phan ln cac thanh tao nay c gan ketchac vi qua trnh bien sinh (metagen), orong cua cat ket thng thap khoang 4-12%di mc trung bnh kha nh gieng khoanD14-STL-1X (hnh 7.39). Nhn chung tiem

nang cha cua cat ket Oligocen co hai mckhac nhau. Phan di, co nhieu rui ro do o

rong nho va phan bo khong on nh. Phan

tren thng gan giong nh cat ket Miocensm, tot hn nhieu nhng s phan bo cuao rong cung khong on nh. Khi xi mangcalcit b ra rua, o rong co the tot, at ti15%, o tham 94,5md (Hnh 7.40), nhngneu xi mang gan chac th o rong lai ratkem.

Cat ket va cat-bot ket Miocen co o

rong thng t 15 en 25% tang dan vepha cac he tang nam tren. Cat ket Miocensm (he tang Phong Chau) mot so ni b ximang calcit hoa manh, o rong nho, songnhn chung o rong va o tham tot hn hancat ket Oligocen va co the at ti 20% vatham kha 139 mD (GK.100/1696m, hnh7.41). Nh vay tiem nang cha cua cat ket

Miocen tot, phan bo rong va on nh gannh trong toan i trung tam MVHN.

Hnh 7.37. Mo hnh chon vui a me, tai khu vc Bac a hao Ly Sn, lo 118 (theo BP, 1995)


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Hau het cac gieng khoan vung TayBac vnh Bac Bo (gieng khoan 102-CQ-1X, 102-HD-1X) va cac gieng tren at lienMVHN eu cho thay rang mac du cat ketco phan bo khap ni trong mat cat nhng

eu co o rong thap. Nhn chung cac tangcat ket Oligocen - Miocen eu co rui ro veo rong, do cac nguyen nhan chnh sau: Cac tang cha chnh co tuoi Oligocen

- Miocen trc ay eu nam rat sau (doo sau cua mong thng t 6-8 km, Trung tam be vt qua 14km), nen ab nen ket rat chat lam giam o rong.

Nhiet o cao, tang anh hng cua quatrnh bien oi th sinh lam giam orong, ngoai ra qua trnh calcit va siderithoa cung lam giam o rong.

Che o tram ong tram tch phc tapnen trong cat ket thanh phan bot va setcao, cat khong sach co o tham thap.Tai phan Trung tam cua be Song Hong,

cac tang Oligocen en Miocen gia trcmat khong phai la oi tng tm kiem do

chung nam rat sau (hn 4.500 m). Riengtram tch Miocen muon-Pliocen TrungTrung Tam vi o sau khoang 2.000 en3.000m co o rong tot (at tren 20%) vao tham tot nh a gap mo ong Fang

(Trung Quoc).Ve pha Nam be Song Hong, cac tap

a cha chnh c xac nh la cac a catket Oligocen - Miocen di va a chacarbonat tuoi Miocen. Cac a cha cat ketOligocen - Miocen thng chu anh hngcua qua trnh bien oi th sinh nen o rongco the b giam i. Cac tap cat nay gieng

118-CVX-1X co o rong trung bnh la 10%,chieu day hieu dung/chieu day chung (N/G)khoang 50%, ty le set t 10 - 12%. Tai mokh Yacheng (Trung Quoc) a phat hien khthng mai t chnh nhng oi tng nayvi o rong t 8 - 15%, o bao hoa nc 20-40%, o tham t vai chuc en vai tram mD.Trong a hao Quang Ngai, cac quat cat la

oi tng tm kiem chnh, vi o rong tothn t 15 - 20%. a cha carbonat Miocen

Hnh 7.38. a voi cha dau tai gieng B10-STB-1X (o sau 1235 m), dolomit toan tinh (sparit),cac lo hong (mau en). Nicol+, X120.


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di-gia he tang Song Hng, Tri Ton laoi tng cha quan trong nhat tai khu vcnay. Cac a cha nay la a voi them, bnt ne va khoi xay am tieu sinh vat, chungphat trien rong rai tren a luy Tri Ton. Cacam tieu sinh vat co tnh chat cha rat tot,

o rong thng at t 25-30%, tham chlen en 35- 40% nh tai gieng khoan 118-

CVX-1X, o tham t hang tram en hangnghn (1000) mD (Hnh 7.42).

Ngoai cac a cha ke tren, cac a tramtch nui la co o rong cao cung co thecha c san pham khu vc cac lo 120,121. pha Nam, oi tng mong nt ne

du cha co gieng khoan nao kiem chngnhng van co the la cac oi tng cha tot

Hnh 7.39. Cat ket nam di mat bat chnh hp Oligocen (IOU) tai GK D14-STL-1X (mau tai 3953,8 m)vi ximang carbonat (mau nau ban), co o rong nguyen sinh nho (mau xanh). Nicol+, X120

(theo Anzoil, 1998)

Hnh 7.40 Cat ket Oligocen hat trung bnh tai gk 100 (mau tai 2181,5 m),co o rong nguyen sinh 15% (mau xanh), o tham 94,5 md. Nicol+, X120


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nh cac vung khac.

6.3. a chan

Tren hnh 7.26 cho thay v tr cac tangchan trong mat cat khu vc. Cac tang chanquan trong nhat eu co mat trong mat catOligocen va Miocen.

Tai MVHN va vung lan can, cac tap setket, set-bot ket thuoc phan tren cua matcat Oligocen tao thanh mot tang chan onnh cho cac bay nam di. Tap chan thcchat la mot tap set bien tien (trangressive),hoac vai ni trung vi mat ngap lut cc ai(maximum flooding surface), co lch s phattrien tng t nh hau het cac be tramtch ong Nam A. Cac tap set Oligocennay tai MVHN la cac tap chan tot do b nenchat va ham lng set cao 70- 80 % set,day t 15-30 m tham ch co ni day 50 m.Con cac tap set ket, set-bot ket, set-than vathan-set trong Miocen phan bo rong va khaon nh trong MVHN vi chat lng chan

tot vi ham lng set 60-70%, chieu daykhoang t 10-15m en 20-25m. Tuy nhien,

nhieu ni, cac man chan trong tram tchOligocen va Miocen b pha v do he thongt gay phc tap hoat ong trong Oligocenva Miocen vi nhieu pha nang - ha, trtbang (strike-slip) va xoay xeo (tilted).

Ngoai khi vnh Bac Bo, cac tap setchan eu co chat lng t tot en rat tot vaco mat hau khap trong mat cat, nhng nhnchung phan bo khong eu, bien oi t Bacxuong Nam va t Tay sang ong do cautruc a chat them luc a va moi trngtram ong bien oi t b ra trung sau. Chieuday a chan Oligocen va Miocen dao ong

trong khoang 10 - 150m vi ham lng setgiao ong t 65-90%.

Mot tang chan co the mang tnh khuvc rong nhat co tuoi Miocen gia, cac trng bi set mau xam, xam en, tngoi ong nhat, day khoang 80m en 150m(gieng khoan 112-BT-1XR) vi ham lngset t 71-86% (gieng khoan VGP- 112-BT-

1X). Cac khoang vat chu yeu la ilit (55%),kaolinit (28%), con lai la clorit va cac

Hnh 7.41. Cat ket hat tho Miocen tai gk 100 (mau tai o sau 1696 m),o rong gia hat 17% (mau xanh), o tham 94,5 md. Nicol+, X120


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khoang vat khac.Cac tang chan a phng Oligocen ac

trng bang set, set than co mau nau, nautham, thanh phan khoang vat gom ilit(48%),

kaolinit (25%), clorit (27%), c tramong trong moi trng ven bien va am layven bien. Cac tap set nay va la tang chanva la tang sinh. Tren at lien, tap set naycung c bat gap cac gieng khoan trencau tao D14 va B10 cua Anzoil.

Cac tang chan a phng tuoi Miocenphan bo xen ke vi cac tap cha. phaBac vnh Bac Bo, cac tap nay la set, setthan. Cang ve pha Nam be Song Hongthanh phan than cang t dan, nhn chung cactang chan a phng eu co chat lng settot, nhng thng co chieu day nho va thayoi nhanh theo dien do ac trng cau truccua them luc a. vnh Bac Bo, hau hetcac gieng khoan eu gap cac tang chan aphng. trung sau cua vnh Bac Bo, tap

set di cua Pliocen la tang chan co chatlng cao co the chan gi cac tch tu kh.

Tong chieu day cua tap set Pliocen co khiat vai tram met.

Ve pha Nam cua be Song Hong cac tapset day Miocen tren va Pliocen di gi vai

tro tang chan khu vc do cac tang nay eunam di sn doc them luc a, o hat ratmn, chieu day ti hang nghn met, b chonvui sau a gan ket (compaction) nen co khanang chan tot.

6.4. Thi gian, di c va tao bay

Ve thi gian sinh thanh hydrocarbon,mot phan a c neu muc 6 a me.

Tong hp t cac phan tch mau, mo hnhlch s chon vui (buried history), mo hnhbe (basin modeling) va cac nghien cu ahoa khac cua cac nha thau dau kh cho motnhan xet chung la be Song Hong do tramtch b chon vui sau, nhiet o cao, nen hientai hau nh cac tang a me co tuoi Eocen-Oligocen a trai qua tat ca cac pha tao san

pham t dau en kh am va condensat. Tuythuoc o sau chon vui, ca so tao kh kho

Hnh 7.42. a cha carbonat Miocen gieng khoan 118-CVX-1X (mau so 4, o sau 1585,9m).a voi (packstone) chaAmphitegina vaLepidocyclina? Cac manh vun sinh vat khac tai tram ong nh

Victorielidva Cyclolypeus, mot loai Echinoderm va manh so


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hien tai trong khoang 3.700 - 5.000 m, caso tao dau bien oi trong khoang 2.200-4.000m.

Ngay sau khi dau kh c sinh thanh,

chung co the di c. Qua trnh dch chuyenban au cua ca dau va kh t a me en baycha eu theo phng thang ng theo tgay, sau o chuyen sang dch chuyen theophng ngang la chnh. Nhng viec tch tudau kh lai phu thuoc nhieu vao tuoi hnhthanh cau tao. Tuoi hnh thanh cac cau tao be Song Hong cung rat a dang. Cac cau

tao c hnh thanh trc Miocen nh cacmong a hnh vui lap, cac vom khoi xoayt gay trong Oligocen, cau tao nghch aoOligocen-Miocen sm; loai nay neu khongb pha huy sau o th thng thuan li choviec tch tu dau kh v c hnh thanhtrc hoac ong thi vi pha di dch chnht a me Eocen-Oligocen. Cac vom co tuoi

Oligocen MVHN, phu bon trung Hue,a hao Anh Vu, a hao Ly Sn hoac caca hao khac thng co nhc iem la cokem theo he thong t gay xoay xeo (tilted)hoac t gay hnh hoa. Nhng t gay nayrat co the a pha v i mot phan cac tchtu dau kh trc o hoac lam that thoat motphan lng dau kh di c ong thi vi tuoihnh thanh t gay. Cac a hnh vui lap cont ne nam ben cac a hao khong sau thngc lai rat thuan li cho viec tch tu dau.

Cac cau tao hnh thanh trong thi kyMiocen gia - muon nh cac cau tao treni nghch ao Miocen, do b nen ep manh,b nang len qua mc nen loai nay thng bbao mon cat xen manh thng la vai trammet en hang nghn met, cang ve pha Tay

va Tay - Nam MVHN mc o bao moncang manh hn. Thi gian bao mon nay co

the keo dai t mot en vai trieu nam. ayla nhng yeu to khong thuan li cho nhngtch tu on nhan dau kh t pha di c chnh.S hnh thanh cac cau tao vom do nghch

ao cuoi Miocen la thi gian muon so vipha di chuyen chnh cua dau kh ra khoi ame Oligocen. Hn na, nghch ao kien taocuoi Miocen con tao nen cac t gay hnhhoa, ma co the mc o nao o, a phahuy i mot lng dau kh a tch tu trco. Nhng nhn chung, pha di chuyen daukh muon la yeu to thi gian thuan li oi

vi cac bay vom Miocen. Cac san phamc di chuyen trong pha muon co the batnguon t cac tch tu co trc b pha huy haypha di c muon t a me Oligocen hay tcac a me Miocen mi c trng thanh.

Tai trung tam Be Song Hong, cac cautao trong Oligocen en Miocen gia thngnam qua sau khong phai oi tng TKTD

hien nay ma oi tng chu yeu c hnhthanh muon hn, co mat trong tram tchMiocen tren va Pliocen nh cac cau taovom kem hoat ong uon nep cua set deo(diapire), cac quat (fan) cat, cac turbidit.Tai ay s trng thanh va di chuyen daukh khoi tang a me co the xay ra trong cacpha khac nhau. Tuy nhien, cac tram tchOligocen - Miocen sm do o sau chon vuiqua ln, nen hien tai vat chat hu c aqua trng thanh (sinh kh kho la chu yeu),trong khi tram tch Miocen gia co a mechat lng kem, sinh kh la chu yeu. Dovay, cac bay tai ay ch hy vong on nhancac tch tu kh (nh cac mo Dong Fang, LeDong).

pha Nam be Song Hong, mo hnh

chon vui tai cac a hao Quang Ngai va LySn cung cho thay pha di c sm cua dau


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dien ra trong thi gian khoang 22 - 10 trieunam trc ay (au Miocen sm en cuoiMiocen gia). Thi iem nay, cac tang chanMiocen gia va tre hn cho cac bay cha

carbonat tren i nang Tri Ton cha hnhthanh do o dau kh a khong c tch tuvao cac bay nay. Ch en pha trng thanhva di c cua kh, cac bay cha carbonat mic nap hydrocarbon. Vi cac bay chaco tang cha la a vun Oligocen - Miocen,neu co cac tang chan hoan chnh th van cothe on c hydrocarbon trong cac pha di

c sm, tuy vay cha co gieng khoan naochng minh c nhan nh nay. Cac thancat bay a tang trong cac a hao QuangNgai va Ly Sn eu kha thuan li cho tchtu dau kh.

6.5. Play, kieu bay va phan bo

Cac play va kieu bay a c trnh baymot phan cac muc 3, muc 5 va muc 7 neu

tren. Tai be Song Hong ch mi phat hiendau kh cha trong ba oi tng cha chnhla cat ket, a voi am tieu-san ho va mongnt ne. Tuy nhien, cac oi tng cha naynam trong cac loai bay cha khac nhau, viac iem kien tao, moi trng thanh tao,tuoi khac nhau va phan bo khac nhau. Trenc s tong hp cac ket qua nghien cu t

trc en nay, di ay se ch ra cac playvi cac vung oi tng chnh (hnh 7.43) be Song Hong.

Cac bay a hnh vui lap (Play 1-Mongphong hoa nt ne)

Nam trong cac a hao Paleogen,thng la khoi mong chon vui, phat trien tat lien ra bien, pho bien nhat la cac khoi

mong a voi Carbon-Permi lo 106 hoacDevon gia - muon lo 112. Cac khoi mong

nay la nhng oi tng hap dan do hai bencanh la cac a hao ni hy vong co tiemnang sinh tot. oi tng nay a c kiemchng bang cac gieng khoan phat hien dau

tai cum mo Weizou cua Trung Quoc, B10-STB tai MVHN va dau hieu dau tai cau taoBach Tr lo 112. Can nhan manh rang namphu tren mong con co cac khep kn bonchieu Oligocen hoac Miocen.

Vung khoi xoay t gay Oligocen (Play2-Oligocen)

Cac cau tao loai nay thng lien quan

en cac khoi xoay t gay (tilted faultblock) hoat ong gan cuoi Oligocen. Phobien nhat la tai trung ong Quan MVHN,lo 114 - 116 va a hao Ly Sn pha onglo 117 - 118. Loai oi tng a c chngminh bang cac phat hien kh D14-STL-1X va mo Yangchen (TQ). Tai a hao LySn co nhieu cau tao rat trien vong, nhng

v mc nc bien sau (400 - 800 m) nenhien cha co gieng kiem tra, trong tng laiay se la oi tng c u tien.

Cac cau tao vom Oligocen-Miocen ketha cac khoi nho mong (Play 2+3)

Loai nay kha pho bien va co the gapbat c au neu co khoi mong nho cao. Taiphu be Hue- a Nang trong pham vi cac lo

112, 114 va Tay - Nam lo 111, oi tngcha nay co the bao gom mong nt ne, catket Oligocen va Miocen. Nhieu cau tao cokch thc tng oi ln nh cac vom khepkn tren mong cua cau tao Bach Tr, Haiyen, ai Bang (hnh 7.21).

Vung cac cau tao nghch ao Oligocen vaMiocen (Play 2+3)

Cac cau tao nghch ao co mat hai vtr trong lat cat: cuoi Oligocen (co ni tiep


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dien au Miocen sm) va trong Miocen gia- muon. ay la loai oi tng rat pho bien be Song Hong va a co cac phat hien daukh kha quan trong nh a noi tren. Cacoi tng nghch ao Miocen co mat dainang Khoai Chau-Tien Hai-Kien Xngtrong at lien, nam kep gia hai t gaySong Chay va Vnh Ninh ti cac lo 102,103

(hnh 7.44, 7.45). Cac cau tao nghch aothng nam tren va ke ap vao cac t gay

nghch, oi tng cha la cat ket Miocen.Cac cau tao c hnh thanh muon vao cuoiMiocen gia, hoan thien vao cuoi Miocen.Mot phan tram tch Miocen muon thng bbao mon cat xen tham ch co cau tao con bbao mon mat ca mot phan tram tch Miocengia. a co 2 phat hien kh trong loai oitng nay la TH-C va cau tao H (lo 103)

nh a noi muc 5.Cac oi tng nghch ao cuoi Oligocen-

11

113112

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QUA N AO H OAN

Vinh

H a i N a m

8083

0 150

km

300 Qui Nhon

Da Nang

Hue

Ha Noi

Hai Phong

Vung cau tao nghch ao Oli-Miocen

Vung cau tao diapir Mio-Pliocen

Vung quat ngam (submarine fan) va turbidit

Mong chon vui carbonat hoac loai khac

Bay a tang ke ap (onlaping, pinchout)

Vom khoi xoay t gay (titled fault block)

Vom khep kn bien o nho Oli-Miocen

Vom khoi xay, am tieu san ho

CHU GIAI 11

113112

114

105

104

7

1

1

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3

3

5

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3102 106

107

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108

109

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QUA N AO H OANQUA N AO H OAN

Vinh

H a i N a m

8083

0 150

km

300 Qui Nhon

Da Nang

Hue

Ha Noi

Hai Phong

Vung cau tao nghch ao Oli-Miocen

Vung cau tao diapir Mio-Pliocen

Vung quat ngam (submarine fan) va turbidit





Vom khoi xay, am tie

gam (submarine fan) va turbidit





Vom khoi xay, am tieu san ho

CHU GIAI

Hnh 7.43. Cac i trien vong dau kh be Song Hong (Huyen N.M 1998, hieu chnh va bo sung 2004)(1) Vung cau tao nghch ao Oligocen-Miocen, (2) Vung cac cau tao diapir Miocen-Pliocen,(3) Vung quat ngam (submarine Fan)& turbidit, (4) Mong chon vui carbonat hoac loai khac,(5) Bay a tang ke ap (onlaping, pinchout), (6) Vom khoi xoay t gay (tilted fault block),

(7) Vom khep kn bien o nho Oligocen-Miocen, (8) Vom khoi xay, am tieu-san ho


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au Miocen sm nh i nghch ao BachLong V (lo 107, hnh 7.14), cau tao Voitrong a hao Anh Vu (lo 111, hnh 7.18)va cac cau tao trong a hao Kim Tc (lo

114, hnh 7.19). Cac cau tao nay thngnam trong cac a hao nho hep, b xoayva oi hng trong qua trnh dch chuyenngang cuoi Oligocen.

Cac bay a tang (onlaping, pinch-out)Oligocen - Miocen (Play 2+3)

Co nhieu cau tao loai nay nam ke aplen them Thanh - Nghe t lo 103 en lo

111. Cac than cat nam ke ap len mat monghoac bat chnh hp noc Oligocen chay doctheo ben canh sut cua t gay Song Chaytrong pham vi lo 103,104 va 105. Tai lo104, lo 111 a phat hien thay mot so cautao dang nay kha hap dan (hnh 7.16). Taicac a hao trong lo 106, 107 hay a haoQuang Ngai cung co the tm thay cac loai

bay tng t. Hien tai, mc o tai lieu conhan che va cha co gieng khoan nao kiemnh kha nang cha san pham cua loai oitng von co nhieu rui ro nay.

Vung cac cau tao lien quan en hoat ongdiapir (Play 3)

Tap trung chu yeu trung Trung Tam,trong pham vi cac lo 109, 110, 111 va 113

(hnh 7.8). Tai ay a phat hien hang loatcac cau tao vom co kch thc ln, nhngbien o nho, t hoat ong t gay. Caccau tao nay lien quan trc tiep en hoatong set diapir. oi tng cha la cat ketMiocen muon va Pliocen. Ve mat cau truc,tiem nang cha, tiem nang sinh th i nayc anh gia co trien vong cao. Tren mat

cat a chan co nhieu d thng bien o lienquan en kha nang cha kh. Phat hien kh

tai cau tao ong Fang cua Trung Quoc vacac cau tao khac a chng minh cho trienvong cua i nay.

Cac oi tng song ngoi, quat ngam va

turbidit (Play 3)Canh giai diapir trung tam la vung phat

trien cac bay a tang dang kenh lach, cacquat ngam (submarine fan) va turbidit.Chung co mat trong lat cat Miocen tren -Pliocen di va co mat cac lo 108, 109,110 (hnh 7.46), ong lo 111, 112, cac lo113 &115 (hnh 7.7) va a hao Quang

Ngai lo 118 (hnh 7.24). Phan ln cacoi tng nay cha co gieng khoan kiemnghiem, nhng chac chan se la nhng oitng trien vong ma trong tng lai phaic quan tam thch ang.

Vung cau tao khoi xay carbonat (Play 4)

oi tng nam trong pham vi cac lo t113 en 121, phat trien tren i nang TriTon vao thi ky Miocen sm - gia, baogom cac cau tao khoi xay carbonat co kchthc cau tao rat ln, chieu day khoanga voi cha kh len en hang tram met,o rong va o tham rat cao. Tai ay a conhng phat hien kh rat ln nh a ctrnh bay muc 5 (hnh 7.22 va 7.23). angtiec, nhng phat hien nay hien cha the

em vao khai thac v thanh phan kh CO2cao. Tuy nhien khi xuong pha Nam cuaa luy Tri Ton, thanh phan CO2 giam dannh ket qua hai gieng khoan 120-CS-1X va121-CM-1X tai lo 120-121.

Tom lai, t cac play va cac dang baycha neu tren co the noi rang chung a ganlien vi thi ky tach gian au tien Eocen-

Oligocen va cac hoat ong t gay, uonnep cung nh ieu kien tram ong va tch


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Hnh 7.44. Ban o cac cau tao nghch ao Miocen (Bach Long, Hong Long, Hoang Long) lo 103-107 (theo PIDC, 2004)

Hnh 7.45. Lat cat qua cau tao Hong Long (theo PIDC, 2004)


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tu tram tch cho en nay. Theo ac iemnguon goc va hnh thai, cung co the chiathanh cac nhom bay chnh: khoi nho mong;

cac nep loi; cac khoi xay carbonat; cac bayhon hp va bay a tang thach hoc. Hnh7.47 la s o phan bo cac cau tao trienvong dau kh ngoai khi be Song Hong.Tuy nhien, do moi vung eu co ac iemkhac biet nen dan en quan iem tham docac oi tng khac nhau, co the tom tat nhsau. Quan iem TKTD vung Tay - Bac be

Song Hong (MVHN va lan can) gom baloai la cac a hnh mong vui lap, cacvom trong Oligocen va vom nghch aoMiocen hnh 7.48. Chi tiet hn, phan bocac cau tao trien vong theo tai lieu hiennay c trnh bay tren hnh 7.49 choMVHN va lan can.

Quan iem TKTD khu vc mien Trungva trung tam be Song Hong. Do them

luc a o doc dan ra trung tam be, cheo kien tao bnh on hn va moi trngtram ong bien oi nhanh t them nc

nong sang sau, nen mo hnh cac bay eTKTD co khac hn phan pha Bac (Hnh7.50). oi tng TKTD chu yeu la cacbay vom khep kn Oligocen-Miocen,cac mong carbonat vui lap, vom va baya tang lien quan en diapir, quat catva cac bay a tang khac.

Quan iem TKTD khu vc pha Nam

(Nam lo 115/116 en lo 121). Mo hnhTKTD cac bay dau kh tap trung vaocac cau tao khoi xay cacbonat tren aluy Tri Ton (Hnh 7.51), cac bay atang ma chu yeu la cac quat cat tronga hao Quang Ngai, cac cau tao hnhhoa hoac khoi xoay t gay trong ahao Ly Sn. Cac cau tao carbonat a

c kiem nghiem qua mot so giengkhoan va a phat hien vi khoi lng

Hnh 7.46. Chanel tren lat cat a chan tuyen BB96-05 (lo 105 qua lo 110) (theo PIDC)


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kh ln, kem thanh phan CO2 cao, nh cac cau tao S T Bien, Ca Heo, Ca VoiXanh. Than cat au tien trong a haoQuang Ngai (cau tao Bach Tuoc) cung

c kiem nghiem bang gieng khoan,ket qua ch cho dau hieu dau kh. Concac oi tng trong a hao Ly Sn canc kiem nghiem trong tng lai khico u ieu kien thuan li.

7. Tiem nang tai nguyen dau kh

Nh a neu, Be Song Hong la mot

trong so nhng be tram tch e Tam rongln khong nhng Viet Nam ma ca ongNam A, ty le phat hien con rat khiem ton,trong khi oi tng tham do va phan bo cuachung rat a dang phong phu.

Tnh a dang va phong phu the hien cho: co 4 loai play vi cac kieu bay khacnhau nh va neu tren, moi loai oi

tng ch co mot hoac vai tham ch cha cogieng khoan tham do; Tren c s tai lieuhien nay a phat hien ra tren 150 cau taoco trien vong, trong so o mi co 37 cautao c khoan chiem ty le 19%, Ngoaitr MVHN va vung nc nong ven b vidien tch khoang 4.000 km2, be Song Hongphan ngoai khi thuoc Viet Nam co dientch khoang 120.000 km2 c chia thanh22 lo, trong o hn mot na so lo cha cogieng khoan nao, so con lai mi co moten hai gieng khoan. Mat o tham do achan mi ch 0,7 km/km2 va mat o khoan1gieng/6.100 km2 la rat thap. Mat o thamdo thap lam anh hng khong nho en viecanh gia tiem nang va trien vong dau kh.V the cho en nay viec anh gia trien vong

va tiem nang dau kh van con nhieu van echa c giai quyet va co nhng anh gia

khac nhau.Nam 1996, trong chng trnh hp tac

vi BP, Petrovietnam a thc hien e ananh gia kh tong the (Vietnam Gas Master

Plan) be Song Hong. e an ch tap trunganh gia cho 4 oi tng chu yeu la mongtrc e Tam, cat ket vung ven (paralic),cat ket turbidit va khoi xay carbonat. Cacoi tng nay c phan bo theo 6 khu vc:i nang Tri Ton, khu vc lo 111-112-114,khu vc paralic doc theo ng b t lo102 ti lo 111 va 3 khu vc khac thuoc cac

lo 101, 102, 103, 105, 106, 107, 108. Ketqua anh gia cho thay t 4 oi tng neutren tiem nang co the thu hoi vao khoang420 ty m3 (khoang 15 Tcf) kh thien nhien,250 trieu barel (40 trieu m3) condensat, 150trieu barel (24 trieu m3) dau va 5 ty m3 khong hanh.

Sau e an tren, nam 1997 Petrovietnam

thc hien anh gia tong the tai nguyentai nguyen dau kh them luc a VietNam (VITRA - Vietnam Total ResourceAssessment, e an hp tac giaPetrovietnam va Nauy), trong o co beSong Hong. Theo e an nay, tong tiem nangthu hoi cua be Song Hong, c tnh cho 4play gom 8 oi tng: mong trc e Tam,cat ket chau tho-song ngoi Oligocen, catket chau tho- song ngoi- am ho Oligocen,cat ket chau tho - song ngoi - bien nongOligocen va Miocen di, bay thach hocOligocen - Miocen, vung nghch ao kientao Miocen, khoi xay carbonat va turbidit,vao khoang 570 - 880 trieu m3 qui dau,trong o a phat hien khoang 250 trieu m3qui dau.

Tren c s ket qua cua e an VITRA,co cap nhat cac so lieu en nam 2004, tr


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Hai phong

Hue

anang

H a i N a m

Ha noi

1000 50

104

103

105

102

109

108

110

106

107

101

111*

112*113*

114*

116*

115

118*

117

119*

120*

121*

122*

GHI CHUVom Oligocen /Miocen

Khoi xay Carbonat(tren)va Clastic (di)

ao va khoi xay carbonat

Diapir

D thng bien o

Cau tao chon vui/mong c arbonat

Ngch ao kien taoBay a tang (onlap, pin chout)

Bay a tang (fan, turbidit)

Nui la

200

500

1000

YachengLedong

Dongfang

Lingtou

Weizhou

Nha may loc dau

ng ong dan kh

o sau nc

Mo dau

D22NE

B22

ng ong dan dau

Mo kh

km

Hai phong

Hue

anang

H a i N a m

Ha noi

1000 50

104

103

105

102

109

108

110

106

107

101

111*

112*113*

114*

116*

115

118*

117

119*

120*

121*

122*

GH

1000 50

104

103

105

102

109

108

110

106

107

101

111*

112*113*

114*

116*

115

118*

117

119*

120*

121*

122*

GHI CHUVom Oligocen /Miocen

Khoi xay Carbonat(tren)va Clastic (di)

ao va khoi xay carbonat

Diapir

D thng bien o

Cau tao chon vui/mong c arbonat

Ngch ao kien taoBay a tang (onlap, pin chout)

Bay a tang (fan, turbidit)

Nui la

200

500

1000

YachengLedong

Dongfang

Lingtou

Weizhou

Nha may loc dau

ng ong dan kh

o sau nc

Mo dau

D22NE

B22

ng ong dan dau

Mo kh

km

Hnh 7.47. Khai quat phan bo cau tao trien vong ngoai khi be Song Hong (theo PIDC, 2004)


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Hung YenFault

Thai BinhFault

PhuongNgai Sag

Vinh NinhFault

Subthrusttrapdoor

closure d24

Dong QuanSag

Song LoFault

D14 Gas

Syn - riftOlig. - (Eoc)

HUNG YENTERRACE

MIOCENE INVERTEDZONE

(Inversion anticlines)

OLIGOCENE TILTEDFAULT BLOCKS(Trapdoor structures)

BURIEDHILL

TREND(Karsted

carbonates)

(Permo-Carb)

B10 Oil

BuriedHillU Olig. Uncon.

Syn rift100to

3500m

1000to

2500m

300mUpper Miocene

WenchAnticlines(Offshore)

MiddleMiocen

e Unc./Hor.

Middle Miocene Blue(MMB)

MiddleMioccene

Kien Xuong Trend Tien Hai Trend

UpperMiocene

IntraOli. Unc.

Plioceneto

Recent

Plioceneto

Recent

Upperto

MiddleMiocene

LowerMioccene

Oligoceneto

Eocene

Oligoceneto

Eocene

TienHai Field

U Miocene Unc.

SW NE

Hnh 7.48. Mo hnh cac oi tng TKTD Mien vong Ha Noi va lan can (theo Anzoil, 1996)

Hnh 7.49. Phan bo cac cau tao trien vong MVHN va lan can (theo PIDC, 2004)


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lng va tiem nang dau kh be Song Hong

co the at khoang 1.100 trieu m3 qui dau,

chu yeu la kh.

en nay, tai be Song Hong mi ch co

9 phat hien kh va dau vi tong tr lng

va tiem nang khoang 255 trieu m3 qui dau,

trong o a khai thac 0,55 ty m3 kh. Cac

phat hien co tr lng ln eu nam tai khuvc vnh Bac Bo va pha Nam be Song

Hong, nh vay, tiem nang kh ngoai bien

ln hn han trong at lien. Tuy nhien, cac

phat hien kh ay co ham lng CO2 cao

nen hien tai cha the khai thac thng mai

c. Tiem nang cha phat hien d bao

vao khoang 845 trieu m3 qui dau, chu yeu

la kh va tap trung ngoai bien. Tr lng

va tiem nang dau kh be Song Hong theomc o tham do va theo play c minh

POSSIBL E MESOZOIC

PALEOZOIC CLASTICS

AND CARB ONATE S

OUTER

BASEMENT

TREND

PALEOGENE

(PG)

MIOCENE

(MI)

SUBMARINE

FAN

BLOCK 113

CLAYDIAPIR

LACUSTRINESR

AL LUV IA L

Dia Chat Va Tai Nguyen Dau Khi Viet Nam - Chuong 7

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Transcript of Dia Chat Va Tai Nguyen Dau Khi Viet Nam - Chuong 7