J OAC DIEM TLTONG, M O I TRUONG TRAM TICH BE JU CHINH - VUNG MAY
QUA KET QUA P H A N T I C H TAI LIEU OjA CHAN
ThS. Li Dye Cong', GS.TSKH. Mai Thanh Un' PGS.TS. Nguyin Trong Tin^ KS. VSn Thj ThoHn' 'Tong cdng ty Thdm dd Khai thdc Ddu Ichi 'Dgi hoc Md - Dia chdt
^Hdi Dia chdt Ddu khi Viet Nam Email: [email protected] Tom t i t
Se trdm tich TU Chinh - Vung Mdy co ddc diim dia chdt phCec tgp, hogt dpng kiin tgo vd ndi l&a dnh hUdng dh cdc qud trinh ldng dgng trdm tich. Qua viec phdn tich, minh gidi dia chdn dia tdng dUa trin quan diim dja tdng phdt\
tdp, kit qud nghiin cuU cua nhdm tdc gid cho phep xdy diing sa do phdn bd, ddc diem tudng vd mdi trudng trdm tich Oligocene, Miocene dudi, Miocene gida vd Miocene tren, cd ddi sdnh vdi kit qud phdn tich tdi liiu dia chdt gieng khoan A. Kit qud nghiin cdu Id tiin di cho cdc nghiin cdu ddnh gid tiem ndng ddu khibiTUChinh - Vung Mdy.
Tdkhda: Dia chdn dja tang, tifdng dia chan, tudng tram tich, m6i tri/dng tram tich. be Ta Chinh - VQng Mdy.
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B l Tu Chinh - Vung May la mdt trcng nhdng be tram tieh nUde siu eda Viet Nam, vdi d i i n tich khoing 90.000km'. Cdng tac tim kilm, tham dd dau khi tai khu vyc Ty Chinh - Vung May duoe b i t dau t d nhdng nam 70 cda t h i ky XX vdi mot sd d l tii/nhiem vu nghien edu v l dae diem dia chit va t i l m nang dau khL Tuy nhiin, do khdi lugng khao sit dja chin tai b l Tu Chinh - Vung May cdn h^n chi, n i n cic v i n de l i i n quan d i n Ijch sd p h i t t r i l n dja chat, dae diem tram tich, moi trUdng thanh tao, he thdng d i u khi chUa duge nghien cdu day du; cac van de v l pham vi phan bd v i d i e diem cda da me, da ehda, d i chin, phin loai bay eda be can dugc lam sang td.
Do khu vUc nghiin cdu chf cd mpt gilng khoan A va chu yeu phli sCf dung tai lieu dia ehan 2D nen viic p h i n chia dia tang khong chi dua v i o cac k i t qua ve thach dja t i n g va sinh dja t i n g eOa gilng khoan n i y m i phai ddi sanh va sd dyng nhdng ket qua nghiin cdu dja tang tai khu vUc thudc phia Ddng -Dong Bac cda be Nam Cdn Son va cic vung lan can [1,5,6,9,13 -15].Dl nghien edu tUdng da va mdi trudng tram tieh, nhdm t i e g i i d l phan tfch cac dac d i l m tUdng dja chin, l i i n k i t vdi k i t q u i phan tich gilng khoan trong cic t r i m tich Oligocene, Miocene dudi, Miocene gida, Miocene t r i n phuc vu cho viee nghien cdu d i n h g i i t i l m nang dau khi (Hinh 1).
Cac mat e i t tudng va mdi trudng t r i m tieh d i e trUng duac xay dung n h i m xie dmh t h i n h p h i n v i t chat, tinh chat tram tich, mdi trudng thanh tao, thdi gian thanh tao eho eac giai doan khic nhau. Kit q u i dat dugc tren co sd B 14 liu m l - s o 3/2015
phan tieh tai lieu g i l n g khoan A va l i i n k i t vdi kit qui phan tfch tudng dia chan theo tai lieu dja chin 2D. Til cae ket qua p h i n tich cae mat e i t mdi trudng tram tfch, vdi elc tap tram tfch Oligocene, Miocene dUdi, Miocene gida, Miocene t r i n va cae b i n dd dang day, nhdm tac gii da xay dung cie so do tudng v i mdi trUdng trim tich, t d dd cung cap cai nhin tdng q u i t ve tiem ning dau khi cda t o i n b l .
Nhdm tac gia da tdng hap ket q u i nghiin cdu, phin tieh mdi quan he gida dac diem tudng tram tich va dac trung trudng sdng dia ehan (Bing 1), cd the ap dung de nghiin cdu tudng, moi trudng t r i m tieh theo tai lieu ^a ehan cho khu vUc nghiin cdu nude sau va cd it gilng khoan [ 2 - 4 , 7 , 8 , 1 0 - 1 2 ] .
2. Oac diem tudng va moi tri/cmg tram ti'cli b l TU Chinh - Vung May
2.1. Ode diem tudng vd mdi trudng tram tich Oligocet\e 2.1.1. Dac diem tudng dia chdn
Tram tich Oligocene va cd hOn tuong dng vdi t i p dia chan nam gida tang phan xa nde mdng va tang phan X|
nde Oligocene. Chieu day cda tap nay thay ddi t d vai tram met d i n tren 3.000m d elc Lo 131,132,153,154 va Ld 155 -157 hoac d eac dja hao nhd xen kep gida cac khoi nhd [2, 14,15]. Dae trUng dja chan la cic t i p tram tich song song, phan Idp tdt, dd lien tye tdt, dang p h i n ldp thau kinh ff^
p h i n ky cd bien dp eao d i n trung binh tai nhdng trung, dia hao v l ban dia hao {Hinh 2 va 3).Tai cac khu vUe khac, xung quanh eac khdi nhd, cic ddi boat dpng nui Ida, phirt^
Tifdng tram tich Tudng luc dia t Tudng ehuyen tiep - Delta Icda sdng
Tudng bien n6ng ven bd
s Tudng them
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I Tudng bien sau f Tudng quat day bien lya quat sudn
g 1. Mdi quon he gida wdng trdm Hdi va tniong sdng dio dian Bac triJng tfUifng song dja chan
Ranh gidl phin xa kem on dinh, khong lien tue, ton tai cac ranh gidi xien cheo, dao khoet song song. Cac mat phin xa manh khdng lien tuc lien quan tdi cac thau kinh than
I - Dpe hudng dong chSy trudng sdng ed dang ehong lan vdi cac mat ph3n xa dang xieh ma. Co eae dau hieu phan Idp song song nam ngang lien quan den cac thanh tao delta
- Theo hudng vuong goe vdi dong chay (song song vdi bc<) trudng song co dang go doi, tdn tai cac go dot xen ke nhau lien quan tdi qua trinh dich ehuyen cua eac delta cda song.
Cac ranh gidi phan xa kem lien tuc, bien do phan xa trung binh. the hien rd tfnh phan Idp, co mat ] eae hoat dong dao khoet. Ton tai cac song phan xa manh lien quan den cac ldp than ven bd, eac I doi cat hay ton tai eae khdi nhojien^quan den cac doi cat ven b6
I The hien ro tinh phan Idp song song nam ngang kha on dinh, do lien tye eCia eac ranh gidi tU I trung binh den tdt. Bien do cua sdng ph^n xa tU trung binh den cao. Cd the ton tai cac song phin ' x^ hen quan den cac ldp carbonate them va ria them. Phan Idp mdng
- Phan ldp nam ngang, do lien tuc cao, bien dp song phan xa td yeu den rat yeu, phan ldp day - Ton tai cae ranh gidi phSn xa tuong doi manh khi trong ldp set bien ton tai cac ldp eat ket hoac bot ket mong.
I TrUdng song h6n dpn (chaotic), eae ranh gicri co dang nem lan va g6 doi
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Hinh 2. Kit qud mmh gidi phdn diia tdp dia didn Oligocene tuyen UI5}
phia Tay Nam khu vUe nghien cu'u, phan xen k i gida eae trung thi dae trUng dja ehan ed b i i n dd trung binh, d6 l i i n tuc kem v i p h i n xa hdn dpn. B l day eda tap nghien edu p h i n phia Nam va Ddng Nam day nhung daetrUng p h i n xa hdn don, b i i n dp thay ddi t d y l u den trung binh, dd liin tuc kem, rat khd xae djnh do anh hudng eda dut gay.
Quan s i t eho thay bien do cda tram tich nay cd xu hudng chung g i l m d i n tu" ndc xudng diy, cd the do dieu kien tram tieh cd eda khu vye thuan loi chc elc tfch ty v i t lieu min va dae trUng d eae dia h i o , b i n dia hao Oligocene. Tram tieh nay cd t h i chia ra lam 2 phan: (1) phan dudi {Oligocene dudi) vdi dac tryng bien dp phan xa y l u , tinh p h i n Idp kem, p h i t t r i l n trong cic dia hao, ban dja hao tuong dng la tudng tram tich luc dia, dam hd ddng b i n g delta vdi mdi trudng ddng bang ven bien; (2) phan tren (Oligocene tren) vdi dac trUng bien dp cao, tinh phan ldp song song, phan ky, dd lien tuc t d trung binh den tdt tUOng dng vdi tUdng tram tich ddng bang chau thd ven bien, tram tich dam hd, hoac chd y l u la tudng tram tfch bien ndng ven bd, bien nong. Mdi trudng tram tich chi'nh la bien ndng d phan phfa Ddng v i mdt phan tren eac trung ke thda d phfa Bic v i Nam khu vye n g h i i n cdu. Tdm lai, theo thdi gian va khdng gian cda mat cat tram tich Oligocene ed sU chuyen tUdng theo quy luat t d tudng tram tfch luc dja, song hd, ddng b i n g ven b i l n sang tUdng tram tich b i l n ndng ven bd, b i l n ndng vdi mdi trudng tram tieh la b i l n nong (Hinh 5 va 6).
Dill KHI-so 3/2015 15
2.1.2. Dpc diem tudng tram tich
Theo k i t qua g i l n g khoan A, he t i n g dupc phat hien tai dp sau 2350 - 2.770m mang ten bai d i e Vung Miy. Tram tfch cua h i t i n g nay phu true t i l p t r i n eac t h i n h tao phun trao, phan dUdi cung cua l i t eat la tap cuoi ket eo sd day vai m i t (gdm eudi granite, granodiorite, it rhyolite, andesite..). Chuyen t i l p tin tren la cac t r i m tfch hat mjn cd mau x i m , xam tro, d i s i t bpt k i t dang phien xen ft eat ket dang quarzite hat nhd, cic Idp mong s i t than. Cat k i t cda h i t i n g cd dp lya chpn, mai tron tdt vdi thanh phan thach anh (25 - 50%), felspath {10 - 25%), manh da (5 - 20% da silica, quarzite, phun trao, carbonate, philn set) (Hinh 4).
Cae tram tich cda h i t i n g t h i n h tao trong dieu kiin nang lucffig t h i p thupc tUdng sdng, chlu tho, dam hd va phan tren cd chju i n h hUdng eda mdi trUcBig biln. Be d i y t r i m tieh cda he tang thay ddi t d 380 - 1.000m. Tai eac trung sau {Vdng Miy, Phdc Nguyin...) be d i y t r i m tieh Paleogene (ehu yeu la Oligocene) theo tai lieu dja vat ly ed t h i dat tOi t r i n 2.000m.
Cac tram tich phien set, phien set ehda than mau den, x i m den d gilng khoan A duge coi ia ed kha nang sinh (chu yeu sinh khi) vdi chat luong kem. Tuy nhiin, cd t h i hy vgng sU tdn tai v i co mat cae d l set ket, set than tudng dam hd va chau thd ven b i l n ed b l d i y Idn hem phan bo tai d c trdng siu, vdi dieu kiin dia chat thuan Igi, chic chan se cd k h i nang sinh d i u khi tdt hon.
So do tudng v i moi trudng t r i m tich Oligocene eho thay khu vue phia Tay ehu y l u la tram tich tue dja, ddng b i n g delta mdi trucmg tue dja. Tudng d p h i n trung tam eua be tram tfch dong b i n g delta, sdng hd vdi mdi tn/dng chuyin tiep, d i m hd chuyin sang mdi trudng bien ndng, phia Bic va p h i n Ddng Nam t r i m tfch cd tudng ddng b i n g ven b i l n , ddng bang delta dudi vdi mdi trudng btin nong tren Kmh 6.
2.2. Ddc diem tudng vd mdi trudng trdm tich Miocen dudi
2 J. 7. Dac diem tudng dia chdn
Trim tich Miocene ducri la tap n i m gida t i n g phan xa nde Oligocene va noc Miocene ducri, b l day tap nay thay ddi ldn t d vai tram met trong p h i n phia Ddng cua vung nghien cdu, mdt p h i n tren khdi nho phia Ddng eua Lo 135,136 va phan khdi nhd eda Lo
\ 16 ltonl-SO3/2015
100 Lim Hinh 4. Man o do sau 2.650m, mm tich Oligocene gieng khoan A
ifinh S. Varcof^o'Vu'c^giKrnrichnjyen j
Hinli6.Sod6tildngvanKitntangtrmtki]Oligo(ene
100 |im Hinh 9. Mlu ddd sdu 2.320m, trdm tich Miocene dUdi gieng khoan A
Hinh 10. Mdt cit mdi trudng trdm lich tuyen 5 131, 132 d i n 1.500m hole hon 2.500m d phan trdng d Ld 156 - 158, p h i n phfa Nam cua Ld 159,160 v l p h i n ria phfa Tay eua khu v y c n g h i i n c d u [ 2 , 1 4 , 1 5 ] .
D i e trung dja chin l i cic t i p t r i m tich song song, phan Idp rd, dp lien tye tdt, b i i n dp manh, d i e b i i t tai cac trdng va p h i n g i n d c khdi nhd hole ddt g i y tai khu vyc nghien cdu. Vdi eae
dac trung nay eho thay tudng tram tich b i l n . Dac biet, tdn tai eae ranh gidi phan xa n i m ngang d gida t i p , c6 d c tap nhd vdi bien dp Idn va dp l i i n tyc tdt, ed le lien quan tdi ddi phat trien cua cac Idp da vdi dang dja phuong va ed the l i cie tap than the h i i n tudng b i l n nong ven bd, bien ndng {?).
Phin tren va phan day eua tap nay d i e trUng dja chan ed dp l i i n tyc trung binh, phan Idp I song song tdi p h i n ky tai cic sUdn cau tao, b i i n do thap d i n rat thap, chju anh hudng cda manh cda d e h i thdng dut gay, bien thien bien dp ngang t r i n khoing each Idn.Trlm tieh gan ngudn vat lieu, d i e trung cho tUdng bien ven bd cd t h i d i m hd va b i l n ndng tUong dng vdi moi trUdng 11 b i l n ndng, b i l n the hien t r i n Hinh 7 v i 8.
2.2.2. Dac diem ti/dng tram tich
Theo k i t qua gieng khoan A, tram tich eda h i tang bao gdm nhieu eat ket, bgt k i t va set kit, xen it ldp set vdi da vdi hole da vdi dolomite. Cit k i t m i u xam, xam den gan ket bdi carbonate v i sit hat nhd d i n mm, do lua chon tdt, mai trdn tdt. Hiu h i t d t k i t thude nhom lithic arkose vdi t h i n h p h i n chu yeu thach anh (25 - 35%), felspath (20 - 40%), m i n h da (5 -15%) va it minh vun sinh vit.
Tram tieh cda h i tang dUOc hinh t h i n h trcng dieu kien ddng bang chau thd ven b i l n (phin dudi) chuyen tiep ten b i l n ven bd, bien ndng (phan tren) vdi be day thay ddi t d 250 - 600m (Hinh 9), mat d t mdi trudng tram tfch duoe xay dung Hinh 10.
Tren so do tUdng va mdi trUdng tram tich tap Miocene dUdi (Hinh 11) khu vUc phia Tay d i e tryng tUdng dong bang ven b i l n , b i l n ndng mdi trydng b i l n ndng p h i t trien da vdi d khu vyc nude ndng. Phan cdn lai co tUdng bien vdi mdi trudng bien ndng chuyen sang b i l n siu, mpt phan phia ddng d khu vUc nude ndng co the p h i t t r i l n cie ddi carbonate them vdi mdi trudng bien s i u tren.
2.3. Ddc diim tUcmg vd mdi trUdng trdm tich Miocene gida
2.3.1. Dac diim tUdng dia chdn
Tap t r i m tieh Miocene gida nam gida tang phan xa Miocene dudi va Miocene gida, chieu d i y khdng Idn {khoing v i i chye met d i n khoing 1.500m), phan bd deu tren toan vung nghien ciJu [2, 14, 15]. Dae trung dja ehan bien dp t h i p d i n
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HmhU.Sa do hmg va moi trudng tram tich Miocene \
100 (im ffinhU.Mdudddsdu2.000m.trdmtidiMiocenegiiiagiengl!hoanA 18 Diu nil-SO 3/2015
trung binh, bien do g i i m d i n t d dUdt l i n tren, do lien tye t d kem tdi trung binh, phan Idp phan ky, ke ap d i y cic p h i n xa I song song, trirdng song tho, ddt doan phan Idp phan ky v l hdn ddn 6 p h i n t r i n eua tap lien quan den hoat dpng bao mdn eat cut, mdt vai vung dac trung II eac ph^n xa trang thay doi manh theo d i i n ngang va ed stf thay ddi bien do theo ehieu sau, anh hydng manh me eda d c dut gay va ndi Ida vi eac hoat ddng ddt g i y h i u h i t k i t thdc trong t i p nay. Dae tri/ng tudng tram tieh gan bd, tram tfch gan nguon vat lieu trong mdi tru'dng b i l n , d c mat d t the hien d i e trung t r i n Hinh 12 va 13.
Phan dudi cda t i p b i i n dd tuang ddi manh, phan ldp song song, dp lien tuc tdt xult hien cac tfn h i i u g i day k l thCra t r i n tap Miocene dudi. Vdi d e dae trurig ve trudng sdng dja chin va ket qua phan tich t d gieng khoan A co t h i dy doan tudng v i mdi trudng tram tich eho tap Miocene giCfa la ddng b i n g ven bien, moi trudng bien den bien siu, t r i m tieh g i n ngudn d e da carbonate phat tnen tren d e ddi nudc ndng phan bd tuong doi phd b i l n trong khu vye hinh thanh trong vdi moi trudng bien den bien siu.
2.3.2. Dac diem tudng tram tich
He tang d I c t r U n g bdi tram tfch lyc nguyen eat k i t mau x i m , hat nhd tdi min, dp lua chpn tdt, mai trdn tdt, gan k i t ehac bdi xi mang carbonate va set, xen k i bdt k i t va set k i t doi khi set voi hoac d t k i t vdi (Hinh 14). Da voi am tieu v i da vdi dang nen xen k i nhau. Carbonate co kha n i n g ehda tdt do sy xuat hien nhieu eua cat 16 rdng d gida va b i n trong tinh t h i , cae hang hde/vi hang hoc.
Tai cic ddi nang t r i m tieh chu y l u la cac da carbonate duoc hinh t h i n h trong d i l u kiin bilrf ndng ven bd, chilu day thay ddi t d 300 - 750m. 0 nhdng trdng sau nhu Vung M i y v i Phdc Nguyin, khdng loai trd kha nang cd sy tdn tai d c t | p trim tieh lue nguyin bao gdm da set, bdt kit, d t l(et, set vdi v i da vdi dang t h i m .
Cac da carbonate cda h i t i n g cd dp rdng, do tham tdt den rat tdt v i dugc eoi la t i n g chdaco chat lugng tdt tuang t y nhu da carbonate b i t i n g Thdng - M i n g Cau ehda khi cd g i i trj thi/ongiiai da phat h i i n duoe d md Lan Tly b l Nam C d F ^ n .
Hinh 15 the h i i n so dd tudng va mdi trudng tram tieh Miocene gida chc khu vye biTuChinh - Vung Miy.
Trong giai doan nay tram tfch ehd y l u la tudng bien ndng d phan phfa Tay Bie, edn lai la cac tram tich mdi trydng bien siu.Trong khu Wc cac dd] nUde nong p h i n bd d phan trung tam va phia Nam trong Miocene gida va p h i t trien cac khdi carbonate mdi trudng bien siu.
2.4. Bgc diem tUdng vd mdi trUdng tram tich Miocen trin
2.4.h Dac diim tUdng dia chdn
Tram tieh Miocene t r i n l i tap nam giQa tang phan xa Miocene gida v i Miocene tren, chieu day cda t i p mdng, mpt sd vung ed t h i v i n g mat nhu vung nhd cao d phi'a Ddng Bac eua khu vyc nghiin cdu, va mdng dan d d c khdi nhd lien quan den d c hoat dpng kien tao ndi ICTa. Chilu d i y thay ddi Idn eho toan khu vye n g h i i n cdXi, khoing v i i met d i n hang tram m i t t r i n hau h i t t o i n bp vung nghiin cdu. NhUng co nai ehilu day cd t h i l i n tdi han 3.000m nhu d khu vUc trung tam Ld 158; p h i n Ddng Nam cda Ld 135,136; mdt phan Ddng Tay eua Ld 159; phia Tly Ld 160 [2,14,15].
Die trung dja chan Ici d c tap tram tich p h i n Idp song song, I song, b i i n dp trung binh den kha va thay ddi manh dan tddudi l i n t r i n , dd l i i n tuc tuong ddi tdt, tinh phan nhjp eda d c tram tich t h i h i i n qua sy thay ddi pha dja chan mdt sd vung tham chf trong suot, t i n sd trung binh den cao d h i u h i t khu vye nghien cdu (Ld 130 - 136, mdt p h i n Ld 154 - 156, Lo 157 - 160), d i y cd t h i la tap set hole bdt set hat mjn hinh t h i n h trong mdi trudng bien sau. Phan edn lai d phfa Ddng khu vye nghien euXi dac trung la d c tap phan xa hdn dpn khdng p h i n ldp, x i i n chio, b i i n dp trung binh d i n cao ed t h i l i cic t i p c i t hole d t k i t xen ke, lien quan d i n khu vyc g i n ngudn vat lieu hoac nguon v i t lieu ke thda t d d e hoat ddng nui Ida.
Nhin chung, tap dia chan nay khdng chju anh hudng cua eae hoat ddng ddt gay t r i n toan khu vye n g h i i n edxi. Vdi d i e d i l m v l dia chin nhu t r i n cd t h i d y doan tram tfch g i n ngudn, sing Ipc tdt trong giai doan bang h i vdi dac trUng bdt s i t l i tudng b i l n trong mdi trudng t r i m tfch chd y l u ia b i l n siu vdi sy p h i t trien cda carbonate t r i n d c ddi nudc ndng mdi trudng b i l n siu (Hinh 16 v i i 7).
2.4.2. Dac diem tUdng trdm tich
Trim tfch cda h i t i n g dUOC d i e trung bdi sU cd mat da carbonate m l u t r i n g , t r i n g phdt xam, dang
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Hinh 15 Sddo tuong va mo traong tram I ch M ocene g Ua
ffmh 16 Ket quo mnhga phan ch a tap da chon M ocene tren tuyen 3 [1]
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Hinh 17 Trch doan mat cat phuc hd trdm tich M ocene trin tuyen 3
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Hinh 18. Mou ado sou 1860m, tram tich Miocene trin gieng khoan A DJhind-s03/2oi5 19 \
Hiah19.Sad6tadngvdmditrUcmgtramtichMioienelrin khdi, r i n chic bao gom da vdi I m t i i u , dang am tieu (Hinh 18), da vdi ehda sinh v i t v i d i vdi dang n l n thudc d c nhdm da packston, wackeston va mudston. Cae khung xuong sinh vat chilm t d 15 - 90% (trung binh 35 - 50%) khae nhau nhieu ve kfch thude, phong phd ve gidng loai gdm d e dang san hd, t i c dd, tao lue.
B l day d e t r i m tich carbonate cda h i t i n g thay ddi td400 - 900m va dUOc eoi l i cac ddi tUOng cd k h i nang ehda rat tdt vdi sU ed mat nhilu d e Id rong hang hoc/
vi hang hdc dugc hinh thanh do sy hoa tan, rda lua cie khoing cda sinh v i t va qua trinh dolomite hda lam co ngot the tich. Ngoai ra, d d e trdng siu ehd y l u la set vdi mdi trudng b i l n d i n b i l n siu eung l i t i n g ehan tot.
Hinh 19 t h i h i i n so dd tudng va mdi trudng t r i m tfch Miocene tren cho khu vyc beTUChfnh -Vung May.Trong giai doan nay tram tich chd y l u la tudng b i l n ndng d p h i n phia Tly Bac, cdn lai la d e t r i m tich moi trUdng bien sau. Khu vye d c ddi nudc nong phan bd phia Tay phit t r i l n cic khdi carbonate moi trudng bien sau.
3. K^t luSn
K i t q u i p h i n tieh die diem tUdng dja ehan k i t hgp t i i lieu gieng khoan A d l xlc djnh va xly dung dUOc d e so do p h i n bd dae diem tudng, mdi trudng tram tich b l Tu Chinh - Vdng M i y vdi d e dac trung sau:
Be TU Chinh - Vdng M i y edng nhu elc be khic tren ria Tay Thii Binh DUOng d l trai qua cie giai doan taeh gian, syt lun nhiit va dugc l i p day bdi d c t h i n h tao ed ngudn gdc va mdi trudng khie nhau:
20 DiUI[Hl-S03/2015
Trong giai doan Oligocene phia Tay cda be phin b6 tudng tram tich luc ^ a , ddng b i n g chiu tho va d i m ti6 cdn d phfa Ddng la tudng tram tich bien ndng.
Trong giai doan Miocene sdm, hau bet dien tieh eiia be duge lap day bdi tram tich bien ven bd va bien ndng.
Cdn trcng giai doan tu'Mioeene gida den Plioeene- D i T d ehu yeu la tudng tram tich bien va bien sau.
Tai lieu tham IthSo
1 Le Ddc Cdng, Mai Thanh Tan, Nguyen Trgng Tin, IVIinh giai tai li$u dja chdn 2D khu vUc Tu Chlnh - Vung Mdy theo phuang phdp dia chan dia tdng. Tap chf Khoa hpc Ky thuat Md - Dia chat. 2011; 34: trang 14-18.
2. LiDdcCdng, Nguyen Trgng Tin, Trjnh Xuan Cudng, Nguyen HCru Quynh, Nguyen Dang Hoang. Ddc diem cSu true dia chat khu vUc be TU Chinh - Vung May dUa tren ket qud minh gidi tai lieu dia chan. Tap chf Dau khi. 2012; 5:
trang 24-30.
3 Le Ddc Cdng, Nguyen Trpng Tin. Dac diem dia chat, phan vung cdu trdc khu vUc be TU Chinh - Vung Mdy. Tuyln tap Hoi nghj Khoa hpc l l n thd 20 Dai hpc Md - Dia chit.
Tap chi Khoa hpc Md -Dja chat. 2012: trang 3 - 1 1 . 4. Mai Thanh Tin. Thdm do dia chdn trong dia chdt dau khi. Nha xuat b i n Giao thdng Van tai. 2007:239 trang, 5. Ngo Xuan Vinh. Dja chdt va tiem nang ddu khi khu vuc ddi nang Tu Chinh, Tay Nam quan ddo TrUdng Sa tren ca sd nghien cdu gieng khoan PV-942X. Tap chi Dau khi. 2000;
4-I-5: trang 2 - 1 4 .
6 Nguyen Trpng Tin, L i Ddc Cong va nnk. Dia chdt ddu khi cdc be trdm tich Kainozoi d viing bien Viet nam.
Tuyen tap Hdi nghj Khoa hpc v l Cdng nghe bien toin qudc lan thd 5. Nha xuat b i n Khoa hgc Ty nhien vaCdng n g h i . 2011: trang 178 - 188.
7. L.F.Brown, W.L.Fisher. Seismic stratigraphy interpretation of depositional systems: Examples from Brazilian rift and pull-apart basins. Seismic Stratigraphy - Applications to Hydrocarbon Exploration, AAPG Memoir.
1977; 26: p. 213-248.
8. B.U.Haq, J.Hardenbol, PR.Vail. IVIesozoic and Cenozoic chronostratigraphy and cycles of sea level change.
Sea-Level Changes. 1988; 42: p. 71 - 108.
9. Mai Thanh Tan. Seismic stratigraphic studies of the continental shelf of SouthernVietnam.Journa\ of Petro\eurt\
Geology. 1995; 18(3): p. 345 - 354.
10. R.M.Mitehum Jr., P.R.Vail.Sejsm/cstrof/grophyand global changes of sea level: Part 7 - Seismic stratigraphic interpretation procedure. Seismic Stratigraphy Applications to Hydrocarbon Exploration. AAPG Memoir.
1977;26,p.l35-143.
11. R.M.Mitehum Jr., PR.Vail, S.Thomson 111. Seismic stratigraphy and global changes of sea level: Part 2 - The depositional sequences as a unit for stratigraphic analysis:
Section 2 - Application of seismic reflection configuration to stratigraphic interpretation. Seismic Stratigraphy Applications to Hydrocarbon Exploration. AAPG Memoir.
1977; 26, p. 53-62.
12. R.M.Mitehum JI., RR.Vail, J.B.Sangree. Seismic stratigraphy and global changes of sea level: Part 6 - Stratigraphic interpretation of seismic reflection patterns in depositional sequences: Section 2 - Application of seismic
reflection configuration to stratigraphic interpretation.
Seismic Stratigraphy Applications to Hydrocarbon Exploration. AAPG Memoir. 1977; 26, p.l 17 - 133.
13. Tdng edng tyTham dd Khai thae Dau khf (PVEP).
Sdo cdo tong ket dia chdt giing khoan PV-94-2X cdu tgo Tu Chinh. ^/^995.
14. Nguyen Trpng Tin va nnk. Nghien cUu cau true dja chdt va ddnh gid tiem nang ddu khi cdc khu vUc TrUdng Sa va Tu Chinh - Vung Mdy". De tai khoa hgc cap Nha nUde KC.09.25/06-10.Vien Dau khiViit Nam. 2011.
15. Tnnh Xuan Cudng va nrik. Tiem nang dau khi khu vuc TuChinh - Vung May - TrUdng Sa. DUan "Danh g i i t i l m nang d i u khi t r i n vdng b i l n v i t h i m lyc dja Viet Nam"
(thudc "De an tdng the ve dieu tra co b i n v i q u i n ly tai nguyin mdi trudng b i l n d i n nam 2010, tam nhin d i n nam 2020"). Viin Dau khiViit Nam. 2012.
Characteristics of facies and depositional environment of Tu Cininh - Vung May basin by the results of seismic data analysis
Le Due Cong\ Mai Thanh Tan' Nguyen Trong Tin''Van Thi Thom^
'Petrovietnam Exploration Production Corporation 'University of Mining and Geology
'Vietnam Association of Petroleum Geology Summary
Tu Chinh - Vung May is a sedimentary basin characterised by complex geology and tectonic and volcanic pro- cesses affecting sedimentation. Through the analysis and interpretation of seismic stratigraphy based on sequence stratigraphy, the results of the study conducted by the authors allow distribution diagrams, characteristics of facies and depositional environment of Oligocene, lower Miocene, middle Miocene and upper Miocene periods to be con- structed and matched with the results of A well's geological materials. The results of this study are the premise for further studies to assess the oil and gas potential of Tu Chinh - Vung May basin.
Key words: Seismic stratigraphy, seismic facies, sediment facies, sedimentary environment, Tu Chinh - Vung May basin.
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