Tuygn tap bao cao Hoi nghj KHCN "30 nam Phu khi Viet Nam: Ca hoi mdi, thach thuc mdi" 5 6 1
D A C D I E M D I A H O A CUA DAU N H E / C O N D E N S A T 6 LO 12W
• • •
BE T R A M TICH N A M C O N S O N
Phan Van Thang Viin Ddu Khi
TOM TAT
Viec thdm dd khai thde ddu khi & Viet Nam da dugc tiin hdnh tu khd lau vd khi ndi din ddu thd Viet Nam ngu&i ta thu&ng liin tu&ng den ddu thd ndng khai thac & bdn trung Ciru Long tir cdc md Bgch Hd, Rgng Ddng, Su Tu Den, Ruby, v.v... Tuy vdy, trong qud trinh tim kiim thdm dd ddu khi & bdn trung Nam Cdn Son ngodi khi tim thdy dugc ngir&i ta cdn phdt hiin ede logi ddu khdc nhu: condensat, ddu thd nhe, ddu thd ndng, v.v.. Trong khudn khd bdi bdo ndy chung tdi mudn trinh bdy nhirng ddc diim dia hda ciia cdc mdu ddu nhe/condensat dugc phdt hiin & Id 12W do Cdng ty Ddu khi Canadian Petroleum thu thdp tu giing khoan 12W-HA-IX thudc be trdm tieh Nam Cdn Son.
Cdc nghien ciiti dia hda dugc thuc hien v&i bon man ddu nhe/condensat trong khodng do sdu tir 3374,5m den 3594m cho thdy rdng cdc mdu ddu ndy cd ngudn gdc chii yeu tir vdt chdt him co luc dia dugc tdch ra cdy hgt kin.
Cdc ddu vit sinh vgt tim thdy trong cdc ddu ndy bao gdm cdc hgp chdt no da vdng nhu: bicydlc sesquiterpanes, non-hopanoid terpanes, hdm lugng thdp hodc hdu nhu vdng mat cdc tricyclic terpanes hay sir hiin diin rdt thdp cua C24 tetracyclic terpanes vd ddc bid Id su chiim uu thi cua C29 sterane so v&i C27 vd C28 sterane. Ddy Id nhirng ddu hiiu ddc trung cua cae logi ddu cd ngudn gdc tu vdt chdt hiru co luc dia.
Cdc n-alkane phdn bd diu tir Cl din xdp xi C30, ngodi ra, chi sd CPI xdp xi 1 ddi v&i tdt cd cdc mdu ddu cho thdy nhirng mdu ddu ndy khd tru&ng thdnh, ty sd pristane/phytane l&n hon 5 chirng td vdt chdt huv co sinh ddu dugc chdn viii trong mdi tru&ng oxy hda cao vd Id ddc diim cua mdi tru&ng trdm tich viing gdn b&, ddm lay hay cdc viing biin m& noi c& ddng gdp ddng ki cua vgt chat hiru ca luc dia.
DAC DIEM DIA HOA CUA CAC MAU DAU LO 12W
Trong bai bao nay cac dii lieu dia hoa dugc khao sat tren b6n mau dau d 16 12W (MDT-1 dau nhe, MDT-2 dau nhe, DST-2 condensat, DST-3 condensat). Nhirng mau dau nay d trang thai long linh dong, kha nhe co trgng lugng API tir 43,64 den 50,12" nen dugc xem la dau nhe hoae condensat. Ngoai ra, ham lugng paraffin kha cao d nhimg mau dau nay, ham lugng wax kha thap (0,9 - 3,2%), ham lugng luu hiiynh rit thip chi d dang vlt (< 0,1%), ham lugng kim loai nhu nickel va vanadium cung kha thip va ty s6 nickel/vanadium kha cao. Nhting dac diem nay phan anh vat chit him co sinh thanh nhirng diu nay co ngu6n g6c luc dia (R. Phiip va Gilberts, 1986) [9], va cung tir cac dac dilm neu tren diu nay cd the dugc phan theo loai D/E (Hinh 1). Nhung phan lich chi till sau se lam ro ngu6n g6c va m6i irudng lang dong ciia vat chit huu ca tao thanh diu nay .
562 Dac digm dja hoa ciia dau nhe/ condensat d 16 12\V bg tr§m tich NamCon^o^n^
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Tuygn tap bao cao Hoi nghi KHCN "30 nam DSu khi Viet Nam: Cff hoi mdi, thach thuc mdi" 563^
1. Sic ky long va dai phan bo gasoline cua cac cau tir hydrocarbon
K i t qua phan tich sic ky long chu y l u la thanh phan nhdm hydrocarbon d ca bdn mau d i u d i u thiy su chiim uu t h i ciia nhdm hydrocarbon no so vdi cac nhdm cdn lai. Thanh p h i n nhdm hydrocarbon thom va phan phan cue (NSO) co ham lugng thip, trong khi do ti s6 hydrocarbon no/hydrocarbon thom la kha cao (7,63 -
12,30) phii hgp vdi ban chat nhe, paraffin tu nhien chua bi bien ddi cua nhOng mau dau nay.
Dai phan b6 hydrocarbon ciia nhirng mau dau nay cho thay sir co mat day dii cac hydrocarbon nhe vdi ham lugng kha cao, ngoai ra sir gi6ng nhau ciia thanh phan C7 d6i vdi tat ca cac mau dau chirng t6 cac dau nay dugc sinh ra tir ciing mgt ngu6n da me.
Chi tiet hon, dai phan b6 gasoline tren sac d6 da chi ro co sir khae nhau dang ke thanh phan tuong d6i cac hgp chat thom. Cu the la cac mau dau n6ng (MDT-1 va DST-3) c6 chi s6 thom tuong irng 1,50 va 1,78 thap hon so vdi cac mau sau hon (MDT-2 va DST- 2) tuong img vdi cac gia tri 2,89 va 3,17. Ket qua sac ky khi ciing cho thay sir chiem uu the ciia cac hgp chat thom gia tang theo do sau va thanh phan cac n-paraffm nhe giam theo chieu sau (Hinh 2). Su thay doi ve thanh phan cac hydrocarbon nhe co the giai thich la do he qua ciia cac qua trinh bien d6i thir sinh nhu bay hoi phan doan ciia h6n hgp khi va dau nhe ben trong via [?].
2. Sy phan bo ciia cac hydrocarbon no tren sac liy do dau toan phan va phan doan C15+ hydrocarbon no
Sir phan bo cac hydrocarbon no ciia cac mau dau nghien ciru tren sac d6 dau loan phan chi ro su n6i trgi ciia n-alkane so vdi cac thanh phan con lai va ham lugng 6xy hydrocarbon ciia cac mau sau cao hon so vdi cac mau nong mot lan nOa khang dinh them hien tugng phan doan do di cu. Ngoai ra, chi s6 CPI xap xi 1 (Bang 1) d6i vdi tat ca cac mau dau chung t6 cac mau nay kha trudng thanh.
Dang phan b6 ciia n-alkane tren sac ky d6 C15+ phan dgan no cua b6n mau dau nay kha gi6ng nhau. Hon niia ty so pristane/C17 kha cao ciing vdi ty s6 pristane/phytane tuong d6i cao (ldn hon 5) (Hinh 2). Nhung dac trung nay thudng gap d cac loai dau ma da me ciia chiing lang dgng trong m6i trudng oxy hoa nhu d cac viing gan bd, dam lay hoae cac vimg bien md vdi su g6p mat chii yeu cua vat chat hiru CO CO ngu6n g6c luc dia (Didyk et al.,1978 ) [3]. Trong nhirng nam gan day, dia hoa hOu CO da phat trien nhieu phuang phap nghien cuu mdi rat huu hieu trong tham do khai thac dau khi. Mgt trong nhirng phuong phap do la phuang phap sir dung sac ky khi ghep kh6i pho (GC-MS) de nghien ciiru diu vlt sinh vat ma cu the hon la cac cau tir hydrocarbon mach nhanh va mach vong ciia dau th6 va da me tir do tim ra ngu6n g6c ciing nhu m6i trudng lang dong cua vat chat htru co sinh dau. Nhtrng phan tiep theo sir dung dir lieu sac ky khi kh6i ph6 (GCMS) dl nghien cuu diu vet sinh vat trong nhtrng mau dau nay .
564 Pac digm dja hoa ciia dau nhe/ condensat d 16 12\V bg trhm tich Nam Cdn Son
Bang 1: Cac thong so dia hoa ciia dau nhe/condensat ff 16 12W be tram tich Nam Con So'n
STT
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A
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4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Thdng sd
Ty trong API Wax (% Kl) Diem chay ( C) Luu huynh (% Kl) Do nhdi (Csl) Saturate/Aromatic Pristane/Phytane Prislane/nC17 Phytane/n-C18 Chi s6 CPI H 1 H_2 H 3 H12 1 H12 2 H 15 H 18 H 19 S 1 S 2 M4
Gidig khoan 12W-HA-1X MDT-1
3374,5m
50,12 1,3
9 0,01 1333.000
12,3 7.56 1,87 0,22 1.00 0,57 0.63 0.83 20,17
8,67 81,52 72,84 107,72
0,57 0,45 86,51
DST-3 3504m
48.52 0.9
9 0,02 1102.000
7.63 8.8 1,91 0.22 1,05 0.6 0,6 0,73 11,93
2,53 117.63 190.39 11.98
0.51 0.46 87,7
MDT-2 3 572-3 594m
43.64 3.2
9 0.02 1655.000
11.33 7.61 2.09 0,23 1.06 0,59 0.61 0,86 23,71
8,92 96.91 95,79 184,53
0,55 0.48 85,72
DST-2 3 5'^ 6m
45.04 2,6
9 0,02 1348.000
6,1 7,59
1,39 0.18 1,03 0,57 0,6 0,84 42,13
8,09 94,1 130,45 103,58 0,59
0,6 81,21
CP1-0.5*((C21+C23+C25+C27)/(C20+C22+C24+C26)+(C21+C23+C25+C27)/(C22+C24+C H_l : C32 HOPANES 22S/(22S+22R)
H_2 : C31 HOPANES 22S/(22S-f22R)
H_3 : C30 HOPANE/(HOPANE+MORETANE)
H12_l : (DE-A OLEANANE/URSANE)/C30 HOPANE ( % ) H12_l : DE-A LUPANE/C30 HOPANE ( % )
H_15 : OLEANANE/HOPANE ( %) H_18 : (Rl+R2+R3)/HOPANE ( %) H_19 : BICADINANE/HOPANE ( %)
S_l : C29 STERANES aaa 20S/(20R+20S) TlT M/Z 217 S_2 : C29 STERANES a(3p 20S/(20R+20S) Tl/ M/Z 218
M4 : C30 HOPANE/{C30 HOPANE+SUM C29 STERANES) %
Tuygn tap bao cao Hgi nghj KHCN "30 nam Phu khi Viet Nam: Cff hoi mdi, thach thuc mdi" 565
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3. Sy phan bo cac cau tir dau vet sinh vat tren pho ciia sac ky khi khoi pho (GC-MS) Nhimg phan tich dau vet sinh vat tren phan doan no ciia cac mau dau nay co nhtrng dac trung sau:
a. Phdn mdnh m/z 123 (Tricycli sesquiterpanes)
Phan manh m/z 123 m6 ta sir phan b6 ciia cac cau tir sesquiterpanes ciia nhiJng mau diu nay dugc chi ro tren Hinh 3. Cac cau tir nay co mat hau nhu trong tat ca cac loai dau, dai phan bo ciia chung tir C15 - C17. Dai dien cac bicyclic sesquiterpanes trong cac mau diu nay la 8p(H)-Drimane va 8p(H)-Homodrimane. Sir phan b6 cac cau tir nay rat gi6ng vdi cac loai diu da tim thiy trudc day d Australia va Newzealand (R. Phiip et al., 1981 andJ^hilp, 1985) [7, 8], nhiing clu tir nay dugc biet la co ngu6n g6c tir vat chat htru co luc dia (Noble R.A., Alexander R., Kagi R.I and Knox J., 1986) [4]. Tac gia Alexander va n.n.k., 1984 [1] thi cho rang nhiing bicyclic alkane ciia cac loai drimane nay co the dugc hinh thanh do nhtrng qua trinh bien d6i sinh vat ciia cac tien hopanoid trong qua trinh hoa da.
b. Phdn mdnh m/z 191 (gdm tricyclic, tetracyclic vd pentacyclie terpanes)
Phan manh m/z 191 bieu thi sir phan b6 cac tricyclic, tetracyclic va pentacyclie terpanes cua cac mau dau d 16 12W nhu d Hinh 4 va bang dinh danh cau tir (Bang 2).
• Tricyclic terpanes
Sir hien dien ciia cac tricyclic terpanes nhin chung la dau hieu ciia ngudn vat lieu bien hoae tao (Aquino Neto et al., 1983, Oung, 1987) [2, 7]. Tuy nhien, cac cau tir nay hau nhu vang mat hoae cd hien dien vdi n6ng do rat thap trong cac mau dau d 16 12W. Dieu nay chimg to rang thuc vat bae cao la ngu6n vat lieu chinh sinh ra dau nay. Day ciing la mgt dac trung ro net ciia dau thudng gap d mgt s6 noi tren the gidi dugc xem la co ngu6n g6c tir luc dia nhu: Ind6nexia, Dai Loan, Oxtraylia, Niu Dilan, v.v... (Phiip and Gilbert,
1986) [9].
• Tetracyclic terpanes
Cac nhom tetracyclic terpanes chii yeu g6m cac cau tir 24/4-l+24/4-2(De-A oleanane/ursane), 24/4-3(De-A lupane) dugc dinh danh tren Hinh 4, ciang gi6ng nhu oleanane co ngu6n g6c tir nhtrng tien than la thuc vat bae cao ma chu yeu la cay hat kin hay noi each khae la tir phan huy nhiet cua tien than pentacyclane. Do vay, su xuat hien de-A oleanane/ursane va de-A lupane vdi n6ng do tuong d6i cao trong cac mau dau nay co the khang dinh rang cac loai thuc vat bae cao la ngu6n vat lieu chinh sinh ra cac dau nay.
• Pentacyclie terpane
Cau tir C30 hopane (m/z 191) cua b6n mau dau cd n6ng do tuong d6i cao so vdi cau tir C30 sterane (m/z 217) vdi gia tri M4 tir 81,21% din 87,70% (Bang 1) va n6ng do tuong d6i ciia ciia hg hopane tir C32-C35 giam dan mgt each deu dan cho thay rang, m6i trudng lang dgng ciia vat chat htm co tao thanh cac dau nay co tinh oxy hoa cao. Ty s6 d6ng phan hoa ciia C31 22S/(22S+22R) d6i vdi nhtrng mau dau nay xap xi 0,6%) (Bang 1) dat nguong can bang, mgt lan ntra khang dinh cac dau nay dugc sinh ra tir da me co do trudng thanh tuong d6i cao.
Tuygn tap bao cao Hoi nghj KHCN "30 nam Dau i<hi Viet Nam: Co' hoi mdi, thach thuc mdi" 567
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568 Bae digm dja h6a ciia dhu nhe/ condensat d 16 12W bl tr§m tich Nam Con Son
Bang 2: Djnh danh cac hop chat terpanes tren manh ph6 m/z 191 va cac hop chat steranes tren manh phi m/z 217
Ten hgp chdt Pic
C23H42 Tricyclic terpane C24H44 Tricyclic terpane C25H45 Tricyclic terpane Des A-Oleanane/Ursane Des A-Lupane
C24H42 Tetracyclic terpane
^26^48 Tricyclic terpane^
C27H50 Tricyclic terpane^
C28H52 Tricyclic terpane^
Cis-cis-tran-bicadinane Tran-tran-tran-bicadinane Bicadinanes
C29 Resine derived cyclic alkanes C30 Resin derived cyclic alkanes 18a(H)-22,29,30-Trisnomeohopane 17a(H)-22,29,30-Trisnorhopane 17a(H), 21p(H)-28,30- Bisnorhopane 17a(H), 2ip(H)-30- Norhopane 18a(H)-30- Nomeohopane PENTACYCLANE PI
17p(H), 21a(H)- 30- Norhopane(moretane) 18a(H)- Oleanane
17a(H), 2lp(H)-Hopane
17P(H). 21a(H)- Hopane(moretane) 17a(H). 21p(H). 22(S)- Homohopane 17a(H), 21 P(H). 22(R)- Homohopane 17a(H). 21p(H), 22(S)- Bishomohopane 17a(H), 21p(H), 22(R)- Bishomohopane 17a(H), 2ip(H), 22(S)- Trishomohopane 17a(H), 21p(H), 22(R)- Trishomohopane 17a(H), 2ip(H), 22(S)- Tetrakishomohopane 17a(H). 21p(H). 22(R)- Tetrakishomohopane
23/3 24/3 25/3
24/4-1+24/4-2 24/4-3
24/4 26/3 27/3 28/3 W T
R,R',W,W' R2'
Rr,Rl,R2,R3 27Ts
27Tm 28aP 29ap 29Ts PI 29pa 300 30ap 30Pa 3 laps 31apR 32apS 32aPR 33apS 33apR 34apS 34apR
Tuygn tap b^o cao Hoi nghj KHCN "30 nSm Dau khi Viet Nam: Cff hoi moi, thach thuc mdi' 569
Bang 2 (tiep theo): Djnh danh cac hyp chat terpanes tren manh pho m/z 191 va cac hop chat steranes tren manh pho m/z 217
Ten hgp chdt Pic
17a(H), 21 p(H), 22(S)- Pentakishomohopane 17a(H), 21p(H), 22(R)- Pentakishomohopane 13p(H), 17a(H), 20S- Diasterane
13p(H),17a(H), 20R-Diasterane 13a(H), 17p(H), 20R- Diasterane 13a(H), 17p(H), 20S- Diasterane
5a(H), 14a(H), 17a(H), 20S- Cholestane 5a(H), 14p(H), 17P(H), 20R- Cholestane 5a(H), 14p(H), 17p(H), 20S- Cholestane 5a(H), 14a(H), 17a(H), 20R- Cholestane 24-Methyl-13 P(H), 17a(H),20S- Cholestane 24-Methyl-13p(H), 17a(H),20R- Cholestane 24-Methyl-13a(H),17p(H),20R-Cholestane 24-Methyl-13a(H),17p(H),20S-Cholestane
24-Methyl-5a(H), 14a(H), 17a(H), 20S-Cholestane 24-Methyl-5a(H), 14p(H), 17p(H), 20R-Cholestane 24-Methyl-5a(H), 14P(H), 17p(H), 20S-Cholestane 24-Methyl-5a(H), 14a(H), 17a(H), 20R-Cholestane 24-Ethyl-13p(H), 17a(H), 20S- Cholestane
24-Ethyl-13P(H), 17a(H), 20R- Cholestane 24-Ethyl-13a(H), i7P(H), 20S- Cholestane 24-Ethyl-13a(H), 17P(H), 20R- Cholestane
24-Ethyl-5a(H), 14a(H), 17a(H), 20S-Cholestane 24-Ethyl-5a(H), 14P(H), 17p(H), 20R-Cholestane 24-Ethyl-5a(H), 14p(H), 17p(H), 20S-Cholestane 24-Ethyl-5a(H), 14a(H), 17a(H), 20R-Cholestane 24-Propyl-5a(H), 14a(H), 17a(H), 20S-Cholestane 24-Propyl -5a(H), 14p(H), 17p(H), 20R-Cholestane 24-Propyl -5a(H), 14p(H), 17p(H), 20S-Cholestane 24-Propyl -5a(H), 14a(H), 17a(H), 20R-Cholestane
35apS 35aPR 27dpS 27dpR 27daS 27daR 27aaS 27ppR 27ppS 27aaR 28dpS 28dpR 28daR 28daS 28aaS 28ppR 28ppS 28aaR 29dpS 29dpR 29daS 29daR 29aaS 29ppR 29PPS 29aaR 30aaS 30ppR 30ppS 30aaR
570 DSc digm dja hda ciia dhu nhe/ condensat d 16 12W bg tr§m tich Nam Cdn Son
Tuygn tap bao cao Hpi nphlKHCN "30 n^m DSu khi Viet Nam: Cff hoi mdi, thach thuc mdi" 571
572 Dac diem dja hda ciia dau nhe/ condensat d 16 12\V bg trhm tich Nam Con Son
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Tuygn tap bao cao Hoi nghj KHCN "30 nam D5u khi Viet Nam: Co hoi mdi, thach thuc mdi" 573
• Non-hopanoid terpanes
Phan manh m/z 191 tren Hinh 4 chi ro mgt vai non-hopanoid co mat trong cac mau diu nay. Dac biet la 18a(H)-oleanane (pic 30O tren Hinh 4) va cac d6ng phan ciia bicadinane cac pic W, W , T ,R ,R' tren Hinh 4 la dau hieu cua vat chat hiru co luc dia dong gop vao su sinh thanh dau nay. Ban dau tac gia Grantham ky hieu cac cau tir n6i bat mdi tim thiy nay lin lugt la W, T, X cho cac mau dau d viing Vien D6ng, ve sau tac gia Cox va n.n.k.. 1986 xac dinh dugc day la cac d6ng phan ciia bicadinane co ngu6n g6c tir cac tien than t6n tai ben trong dammar resins. Sir c6 mat cua cac cau tir nay trong tat ca cac mau dau d 16 12W la dau hieu ciia vat chat htm co luc dia hinh thanh nen da me ciia nhiing dau nay, nhtrng hgp chat nay da dugc tim thay d6i vdi cac loai dau co ngu6n g6c luc dia nhu d Brunei, Sabah va Ind6nexia (Grantham et al., 1983; Whitehead, 1974) [4, 10]. Tuy vay, cac tac gia Phiip va Gilbert chi ro rang 18a(H)-oleanane kh6ng hoan loan vang mat trong tat ca cac loai dau d ky Triat/Jura b6n triing Surat/Bowen d Oxtraylia mac dii CO dau vet ciia thuc vat bae cao trong da me cua cac dau nay. Do d6, co the noi mgt each hgp ly la sir xuat hien ciia oleanane d6ng thdi vdi su tien hoa ciia cay hat kin tir Creta thugng cho tdi hien tai. Ngoai ra, cac C30 resin co ngu6n g6c tir alkane (cac pic R r , R l , R2, R3 d Hinh 4 va dugc dinh danh d Bang 2), cac cau tir nay xuat hien vdi n6ng do kha cao, gia tri HI8 tir 72,84%) den 190,39% (Bang 1) mac dii viec xac nhan cac cau tir nay chua ro rang song sir xuat hien ciia chiing trong cac loai dau cd ngu6n g6c bien va kha ph6 bien trong cac loai dau ma d do oleanane hien dien vdi n6ng do cao. Do vay, sir xuat hien ciia cac cau tir nay trong cac mau dau d 16 12W co the khang dinh cac loai dau nay dugc sinh ra tir da me co ngu6n g6c luc dia.
• Sterane (Phdn mdnh m/z 217)
Su phan b6 ciia sterane trong b6n mau dau nghien cim tren day la kha gi6ng nhau chimg to chiing dugc sinh ra tir mgt ngu6n vat chat hiin co. Pho sac d6 m6 ta su phan b6 cua sterane tren Hinh 5 va dugc dinh danh d Bang 2, tren phd sac d6 nay chi ro sir trgi n6i ciia C29 regular va rearranged steranes so vdi n6ng do tuong d6i thap cua C27 va C28 steranes. Dac trung nay khang dinh vat chat htru co luc dia la ngu6n vat lieu chinh sinh diu d 16 12W.
KET LUAN
Cac mau dau dugc xem xet d 16 12W trong nghien ciru nay la loai dau nhe/condensat CO ham lugng wax thap, ham lugng luu huynh va asphaltene kha thap ben canh do ham lugng cac kim loai nhu nikel va vanadium ciing kha thap. Nhiing dac diem nay phan anh vat chat huu co sinh dau nay co ngu6n g6c luc dia . Hon the ntra su phan b6 kha cao cac n- alkane va ty s6 pristane/phytane kha cao (ldn hon 5) ciing vdi sir hien dien cua cac C24 tetracyclic terpanes, sir trgi n6i cua C29 sterane, sir hien dien ciia cac dau vet sinh vat kbac nhu: de-A oleanane/ursane, de-A lupane va dac biet la sir xuat hien vdi n6ng do cao cau tir oleanane. Tir nhting dac diem dia hoa tren cho thiy ring nhting mau dau nay dugc sinh ra tir mgt ngu6n da me ma d do thuc vat bae cao la ngu6n vat lieu chinh cu thi hon la cay hat kin da xuat hien tir Creta thugng cho din hien tai.
574 Dac digm dja hoa ciia dau nhe/ condensat d 16 12W bg trhm tich Nam C6n Son^
Nhimg dii: lieu dia hoa ndi tren ciing chi ro m6i trudng trim tich ciia da me hinh thanh nen diu nay d vimg gan bd, dam lay hay bien md dieu kien tuong d6i oxy hoa ma d do thuc vat bae cao la ngu6n vat lieu chinh dong gop su tao thanh diu nay.
Nhiing diu nhe/condensat nay co the kh6ng dugc tao thanh tir da me qua trudng thanh, ham lugng cac hgp chit thom phan di theo chieu sau (cang xudng sau cang tang) co thi do anh hudng ciia qua trinh di cu.
TAI LIEU THAM KHAO
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2. Aquino Neto F.R., Trendal J.M., Resile A., Albrechtp, Connan J., 1983. Occurrence and formation of tricyclic and tetracyclic terpanes in sediment and petroleum. In Advances in organic geochemistry 1981 (edited by Bjoroy M. et al.).
3. Didyk B.M., Simoneit B.R.T., Brassell S.C, Eglinton G., 1978. Organic geochemical indicators ofpalioenvironmental conditions of sedimentation. Nature 271, p. 216 - 222.
4. Grantham P.J., Posthuma J., Baak A., 1983. Triterpanes in a number of Far Eeatern crude od. In Advances in organic geochemistry 1981, p. 710 - 724.
5. Noble R.A., Alexxander R., Kagi R.L, Knox J., 1986. Identification of some diterprenoid hydrocarbon in petroleum. In: Advances in organic geochemistry 1985.
Org Geochem 10, p. 825 - 829, Perganon press, Oxford.
6. Noble R., Knox J., Alexander R., Kagi R.L, 1985. Identification tetracyclic terpanes hydrocarbons in Australia crude oils and sediments. J. chem. soc. chem. common, p. 32 - 3 3 .
7. Oung J.N., 1987. Tricyclic terpanes and related compounds in crude oils and source rock extracts. M.Sc. Thesis, University of Oklahoma.
8. Phiip R.P., 1985. Biological markers In fossil fuel production. Spectrom, Rev., p. 41 - 54.
9. Phiip R.P., Gilbert T.D., 1986. Biomarker distribution in Australia oil predominantly derived from terrigenous source material. In: Advances in organic geochemistry 1988.
10. Whitehead E.V., 1974. The structure of petroleum pentacyclie. In: Advanced in organic geochemistry 1973.
11. Pham Thi Toan, Nguyen Xuan Thanh, 1996. Geochemical evaluation two mdt oils and gas at 3374.5m and 3576m in the 12W-HA-lXwell.
