0r9. 6e~hem. V~. 2~ N0. 1~11, pp. 947-955, 1996 C0pyf19~ • 1996 ~ 5~ence ~d

Pr1n~ed ~ 6reat 8r1ta1n. ~1 f19h~ ~5erved P1~ 50146-6380(96)00090-3 014~638~96 $15.00 + 0.~

Em~f1c~ car60n 150t0pe/matur1ty rdaf10n5~p5 ~r 9a5e5 ~0m ~9~ ker09en5 and ~rf19en0u5 0r9a~c ma~e~ 6a5ed 0n dr~ 0pe~5y5~m

pyr~y~5

ULR1CH 8ERNER and ECKHARD FA8ER

Feder~ 1n5t1tu~ f0r 6e0~nce5 and Natura1 R ~ 0 u ~ , 5t11~we9 ~ D-30631, Hann0v~, 6~many

A~act--Pyr01y5e5 expef1men~ (dry, 0pen-5y5~m) 0n f19~ ker09en5 and ~nd~ant m~ef1~ (8~n~ et a1., 199~ have 5h0wn that car60n ~0t0~c var1at10n5 0f m~han~ ~hane and pr0pane 06t~ned ~0m ~60r~0ry f1mdaf10n5 m1m1c ~0t0pe var1at10n5 0f n~urf1 therm~ 9 a ~ 7he~ ~0t0pe var1at10n5 can 6e appr0~ma~d thr0u9h ~net1c m0dd5 (8erner et a1., 199~. A150, m~ur1~ parame~ f1ke ~ t r 1 ~ ~f1e~ance and R0ck-Evf1 7m~ are re1~y cf1c~ed ~0m ~nef1c m0dd5 th~ a~ 6a~d 0n pyr~yf15 expef1men~. U~fr1endy verf10n5 0f 150t0pe/matur1ty m0dd5 f0r m~han~ ethane and pr0pane were 06t~ned ~0m appf1cat10n 0f ~at15t1ca1 curve-f1tt1n9 pr0cedu~5 t0 the m 5 ~ 0f 1n~an~ne0u5 ~nef1c m0dd5 0f 8erner ~ ~1. 099~. 7te re5u1t1n9 51mp1e em~r1c~ fur ct10n5 ~ car60n 150t0~c var1at10n5 0f f19ht hydr0car60n5 ~rect1y t0 50u~e r0ck m~ur1ty and can 6e app11ed whe~ 9a5e5 have accumu- 1a~d 1n5tantane0u51y. 7hey a110w f1ef1~e c~cdat10n5 that acc0unt f0r car60n ~0t0~c var1a6f1~y 0f precur50r f1~5 0f the 1nd1~du~ 9a~5. Ap~at10n 0f the m0dd e n a ~ detect10n 0f m1f1n9 6~ween 6acter1a1 and therm~ 9a5e5, a5 we11 a5 m1f1n9 6etween therm~ 9a5e5 0f ~ffe~nt m~uf1f1~. 7he app11- cat10n 0f the pr0p05ed m0dd5 15 dem0n~ra~d ~ tw0 ca5e ~ud~5 (6~en 7uff 8af1n, Japa~ C00per 8af1n, Au5tr~1a) w1th da~ ~ken ~0m the 11~tu~ (R~6y and 5m1th, 1981; 5 a k ~ 1991). C0pyr19ht ~C 1996 E1~v~r 5dence L~

Key w0rd5--car60n ~m0pe rat105, m~uf1ff m0dd~ m~han~ ~han~ pr0pan~ f1muht10n 0f 9~ 9ene~ at1~n, 0pen-5y5tem pyr01y515

1N7R0DUC710N

Dur1n9 the 1a5t tw0 decade5 a var1ety 0f m0de15 ha5 6een pr0p05ed that re1ate car60n 150t0pe rat105 0f natura1 9a5e5 t0 50urce r0ck matur1t1e5. 7he p10- neer1n9 w0rk5 0f 5tah1 (1968) and 5tah1 and Carey (1975) have 5h0wn that emp1r1ca1 re1at10n5 ex15t 6etween the matur1ty 0f 50urce r0ck5 (v1tr1n1te ref1ectance, VR) and the ~0t0p~ c0mp0rf10n 0f re- 1ated 9a5e0u5 hydr0car60n5.

6enera11y, car60n ~0t0pe va1ue5 0f therma1 9a5e5 are th0u9ht t0 1ncrea5e w1th 1ncrearn9 matur1ty 0f the1r precur50r5. 7h15 15 exp1a1ned thr0u9h a k1net1c ~0t0pe effect 6y wh1ch ~C-1~C 60nd5 0f the ker0- 9en are preferent1a11y cracked, ~ad1n9 t0 an enr1ch- ment 0f 13C 1n the precur50r r1te5 0f the 9a5e~ wherea5 119ht hydr0car60n5 are dep1eted 1n ~3C c0mpared t0 the ker09en.

5evera1 re5earcher5 (5und6er9 and 8ennetL 1983; P1n9 and Y0n9chan9, 1986; 5chf1t2e and M~h1e, 1986; Fa6eL 1987; Chun9 et a1., 1988; 6a11m0v, 1988; 8erneL 1989; 2han9 and Fen9, 1990; Jame5, 1990; C1ayt0n, 1991; 8erner et a1., 1992) have pr0p05ed the u5e car60n ~0t0pe5 0f 9a5e5 1n hydr0- car60n exp10rat10n. 7he advanta9e5 and d15advan- ta9e5 0f the 1nd1v1dua1 m0de15 are d15cu55ed e15ewhere (8erner and Fa6eL 1993).

8erner et aL (1995) pre5en~d a new appr0ach t0 the u5e 0f car60n ~0t0pe5 1n hydr0car60n exp10ra- t10n. 7hey have 5h0wn that car60n ~0t0p1c var1- at10n5 0f methane, ethane and pr0pane, 06ta1ned ~0m h60rat0ry rmu1af10n5 0f pr1mary ctack1n9, m1m~ ~0t0pe var1at10n5 0f natur~ therma1 9a5e5. 7hey c0nducted pyr01yr5 exper1men~ (dry, 0pen- 5y~em) 0n an ~ 9 ~ ker09en and h n d p h n t mater1~. 7he ~0t0p1c var1at10n5 0f the re5u1t1n9 9a5e0u5 hydr0car60n5 c0u1d 6e appr0~ma~d thr0u9h a c0m61nat10n 0f k1net1c and Ray1e19h-ffact10naf10n m0dd5 (8erner et a1., 1995). 7he5e ~0t0pe m0dd5 are c0m61ned w1th matur1ty parameter5 5uch a5 f1tr1n1~ ref1ectance ( V R ) and R0ck-Ev~ 7m~ that are re11a6~ ca~u1ated ~0m k1net1c m0dd5 6a5ed 0n pyr0~r5 exper1men~. 7he m0dd der1ved ~0m py- r01y5~ 0f the a~a1 ker09en may a150 6e appf1ca61e t0 9a5 9enerat10n ~0m th05e hpt1n1t1c and ex1n1f1c 5u6~ance5 that may n0t have a mar1ne 0r 1acu5tr1ne phyt0p1ankf1c 0r1~n. 7h15 a~umpf10n ~eem5 t0 6e va11d, a5 the5e 5pedf1c precur50r5 c0n515t 0f 10n9- ch~n hp1d5 rather than ar0mat1c 5tructure5.

H0weveL the app1~at10n 0f the m0dd5 0f 8erner et aL (1995) re4u1re5 1nr9ht 1nt0 the the0ry 0f k1net1c m0dehn9 and c0mputer pr09ramm1n9 capa- 61~t1e5. 7h15 ~m~5 the app~cat10n 1n ca5e ~ud~5.

947

948 U1r1ch 8erner and Eckhard Fa6er

We theref0re pre5ent a new appr0ach that u5e5 a 5tat15t1ca1 eva1uat10n app11ed t0 the k1net1c m0de15 0f 9a5 9enerat10n ~0m a19a1 ker09en5 and 1andp1ant mater1a1 (8erner et a1., 1995). 7he re5u1t1n9 e4uat10n5 repre5ent f1mp1e 6ut f1ex161e m0dd5 f0r 1n5tantane0u5 accumu1at10n that re1ate ~0t0pe rat105 0f 9a5e5 t0 50urce r0ck matur1t1e5. 7he term ~1n5tantane0u9~ refer5 t0 the c0mp0~f10n 0f 9a5e5 9enerated at any 91ven matur1ty.

D E V E L 0 P M E N 7 0 F M 0 D E L 5

6a5e5 fr0m 7ype 11 ker09en5

50me m0dd5 (5chf1t2e and Mf1~e, 1986; 2han9 and Fen~ 1990; C1ayt0~ 1991) a55ume ~eady ac- cum~af10n 0f 9a~5 ~ a ~ r v ~ r even up t0 the ~9he~ matur1t1e5. 7~5, ~ 0ur 0 ~ 0 ~ 15 a de6ata- ~e p~nt , a5 f1111n9 a ~ r v ~ r ~ a dynam1c pr0ce55 1n w~ch hydr0car60n5 accumu1a~ 0ver a c e ~ n ran9e 0f m~uf1t1e5 6ut ~50 may 6e par t~ ~5t. E x a m ~ f0r the5e ~5~5 0f 9a5 a ~ ~ffuf10n thr0u9h the cap r0ck ~ £ Leythaeu5er and 5chae~L 1984) 0r tect0~c pr0ce55e~ a5 1nverf10n that ha5 6een 065erved ~ 50me ~ r v ~ 0f NW 6ermany ~£ 5ch0e11, 198~. A1th0u9~ we d0 n0t p05tuh~ that ~ r v ~ r f1111n9 15 an ent1re1y 1n5tantane0u5 pr0- ce55, we ~ c d v e ar9ument5 ff0m f1dd ~ u ~ (6er~n9, per5. c0mmun., 1995) that ~ many ca5e5 the pr0ce55 0f a c c u m ~ n can 6e d05e t0 an 1n- 5tantane0u5 f1tuat10n. We are t0ta1~ aware that

under 1de~ 9e010~c~ ~rcum~ance5 the pr0ce55 0f 9a5 accumu~t10n may 6e d05er t0 an 1nte9r~ f11~n9 when the 1055 0f 9a5 15 retarded, f0r examp1e 6y a t19ht cap r0ck.

7he re5u~5 0f c0mputat10n~ uf1n9 the k1net1c m0dd5 0f 8erner et aL (1995) that de5cr16e 1n5tan- tane0u5 9a5 9enerat10n w1th 1ncreaf1n9 matur1ty 0f an a19~ ker09en, are 5h0wn 1n F19. 1.

7he ~0t0p1c var1at10n5 0f methan~ ethane and pr0pane are rdated t0 an 1n1t1~ car60n ~0t0pe va1ue 0f the ker09en 0f -30%. Uf1n9 c 0 m m e r ~ 1 y ava11a61e curve-f1~1n9 pr09ram5, we are n0w a61e t0 06t~n f1mp~ n0n-11near e4uat10n5 that rdate matur1ty t0 h0t0pe rat105 0f methan~ ethane and pr0pane acc0rd1n9 t0 data 1n F19. 1.

7he var1at10n 0f 150t0pe rat105 0f methane (~1n) can 6e de5cr16ed a5 a funct10n 0f matur1ty (VR) thr0u9h the e4uat10n

81m = -4.0613VR 5 + 34.924VR 4 - 113VR 3

+171.26VR 2 - 111.86VR - 20.735

~ r e 1 a t 1 0 n : r 2 = 0999~. (1)

7~5 ~ncf10n app11~ t0 the 1n5tantane0u5 ca5e, and 15 va11d 6~ween 0~ and 25% VR.

7he appr0x1mat10n 0f ~ e ~net1c m0dd 0f ~ a ~ tane0u5 ethane 9enerat10n ~0m an M9M k e ~ n 6~ween 0.6 and 2.0% VR 15 ~ven ~ u 9 h

--20

--25

--30

~ -35 -- 00

--40

--45

M0de1

- k1net, e m ~

M ~ h ~ e 0

Ethane A ~

- Pr0pane [] [ ] ~

~ - ~ ~

~ ~ ~

• /

-

- -

- -

-50 1 1 1 1 1 1 0.5 1.0 1.5 2.0 2.5 3.0

V R ( % )

F1~ 1. Em~r1c~ m0d¢~ that de~r16¢ ~ a n t a n e 0 u 5 9a5 9enerat10n ~0m ~9a1 ker09en5 have 6een de- r1ved thr0u9h 5tat15t1ca1 ev~uat10n 0f ~nef1c m0dd5 0f 8erne ~ aL (199~.

Em~f1c~ ~ n ~ m f 1 ~ ~ 1 ~ 949

~m = 7.4~1VR 6 - 81.~6VR 5 + 3 ~ V ~

- - ~ 2 . ~ 3 + ~ 1 . ~ 2 -- ~ 2 ~ + 6 ~ 0 8 3

~ 0 ~ d ~ n : ~ = ~995~, (2)

whe~ 6~n den0te5 the 1n5tantane0u5 car60n ~ 0 ~ p e rat10 0f ethane (F19. 1).

1n5tantane0u5 car60n 150t0pe rat105 0f pr0pane 63111 and m~ur1~ VR 0f an ~ 9 ~ ker09en are de~r16ed ~r0u9h e4uat10n

33m = -2~174VR 6 + 8.294VR 5 + 1~76VR 4

- 1 ~ . 8 7 V R 3 + ~ 4 ~ 2 -- 165.11 ~ + 3.875

~0rrdat10n : ~ = ~9947). (3)

E4uat10n (3) 15 v~1d 6etween 0.6 and 2.0% VR (F19. 1).

A5 e4uat10n5 (1)-(3) 0n1y de5cr16e car60n ~0t0p1c var1at10n5 0f 9a5e5 ~0m a19a1 ker09en5 w1th an 1n- 1t1a1 150t0pe rat10 0 f - 3 0 % , we have t0 m0d1fy (1)- (3) 5119ht1y t0 acc0unt f0r d1fferent ~0t0p1c c0mp0- f1t10n5 0f ker09en5. 7he 9enera1 f0rm5 0f the

e4uat10n5 that rdate the ma~r1ff 0f ~ 9 ~ ker09e~ t0 ~ 0 ~ p e rat105 0f m~han~ ethane and pr0pane are ~ven ~ u 9 h

~ 1 = 3~1n + N 0 - 18~1] (~5~nmne0u5 m e ~ a n ~ ,

(4)

* ~2111 = ~2n1 + N 0 -- 1~1] (~5mn~ne0u5 e~an~ , (5)

~1f1 = ~3111 + N 0 -- 1~11] (~5mnmHe0U5p90pa~,

~)

whe~ 6n den0te5 the 1~f1f1 car60n ~0t0pe rat105 0f f19a1 9a5 precur50r5.

A5 5h0wn 1n F195 2a and 6, the new maan- tane0u5 m0dd5 ~4uat10n5 (4)-(~) der1ved ~0m py- rCyf15 exper1ment5, c0u~ed w1th a ~net1c c0ncept and a ~ a t 1 ~ ev~uat10n, are f1m11ar t0 the enf1rdy em~r1cM 0n~anmne0u~ m0dd5 f0r 9a5e5 ~0m 5apr0pef1c ker09en5 0f 5 ta~ and Carey (1975) and Fa6er (198~. F0r t~5 c0mpar150n we a55ume that the 9a5 p ~ c u ~ 0 ~ 0f the 5apr0pe11c ker09en5 0f the VM V ~ d ~ D d a w a ~ 8af1n5 have ~1f1~ 150t0pe rat105 0 f - 2 7 % ~£ R00ney ~ a1., 1995).

-15

-20 --

3 ~ -25 - -

N ~ -30 - -

-35 --

-~0 -50

-15 --

-20 --

~ -25 - -

r0 ~ -30 --

-35 --

-40 -45

(a)

2.4

Fa6er 1987• ~

~ 2 0 ~

VR (%) 1 ~

~ . ~

0 . 6 ~

-45 -40 -35 -30 25 -20

81~Methan e (°/m)

(6) Fa6er 1987] 2.4

/ 0 . 6 ~

-40 -35 -30 -25 -20 - 15

~13CEthane (°/c0)

F1~ 2. C0mpar150n 6etween the emp1f1cM m0d~ 0f Fa6er (1987) (fr0m re5erv~r 9a5e~ and the ~nef1- ca~emp1f1ca1 m0dd ~h15 pape~.

950 U1r1ch 8erner and Eckhard Fa6er

- 1 8

- 2 0

- 2 2

5 ~ - 2 4 ~

--

--26

--28

--30

1 ~

1.0 1.5 2.0 2.5

V R ( % )

0 0.5

1 3.0

F19. 3. 5 t a t 1 ~ ev~uaf10n 0f car60n ~0t0pe rat105 0f methane, ethane and pr0pane ~0m pyr01yf15 0f xy11~ (8emer et a1., 1995). Ref1ectance data (VR %) ha5 6een ca~u1ated ~0m the k1net1c m0de1 0f f1tf1n1~ ~rat10n 0f

8erner et aL (1995).

6a5e5 f r0m 1andp1ant ker09en5 and c0a~ (7ype 111 9a5e5)

D1fferent ~0m the der1vat10n 0f m0dd5 0f 9a5e5 0f M9a1 type ker09en~ we f1t re9re5510n curve5 t0 the mea5ured 150t0pe data and ca~u1a~d matur1t1e5 f0r 9a5e5 0f 1andp1ant ker09en5 and c0M5. We have ch05en th15 appr0ach, a5 the k1net1c m0dd5 0f 8erner et aL (1995) d0 n0t 5at~fact0r1~ c0unt f0r the N0t0p1c var1a6111ty 0f the 9a5e5 6ecau5e 0f the 150t0p1c c0mp1e~ty and heter09en~ty 0f the 0r9an1c precur50r5. Car60n 150t0pe rat105 0f methane, ethane and pr0pane ~0m a pyr01yN5 exper1ment 0f 8erner et aL (1995), u~n9 1andp1ant xy11~ 0f a

Hd~0cene c0n1fe~ have 6een c0rre1ated w1th ca~u- 1ated VR-va1ue5 (F19. 3). Va1ue5 0f VR were c0m- puted fr0m the k1net1c v1tr1n1te-a1terat10n m0dd 0f 8erner et aL (1995) app1y1n9 a heat1n9 rate 0f 5°C/ m1n wh1ch wa5 u5ed 1n the 1a60rat0ry exper1ment.

F0r 0ur methane 150t0pe and matur1ty c0rre- 1at10n, we 0n1y u5e data 6etween matur1t1e5 0f 1.5% and 2.5% VR (F19. 3), f0r wh1ch 8erner et aL (1995) de5cr16e an 1ncrea5e 0f ~3C 1n methan~ typ1- ca1 f0r a k1net~ ~0t0pe effect that 0ne w0u1d expect a550dated w1th car60n-60nd 6reaka9e 0f the pre- cur50r. F0r 10wer matur1t1e5, 8erner et a1. (1995) 065erved m1x1n9 6etween methane 0f d1fferent methane 9enerat1n9 react10n5 that p01nt t0 a c0n- f1dera61e ~0t0p1c 1nh0m09en~ty 0f the methane f0rm1n9 f1te5 w1th1n the 0r9an1c mater1a1. H0weve~ 0ur f1near re9re5f10n

8~n, = 3.6848 V R - 31.292

(c0rrdat10n : ~ = ~9707) (7)

acc0unt5 very we11 f0r the var1at10n 0f car60n 150- t0pe rat105 0f 1n5tantane0u5 methane 6~m 0ver a matur1ty ran9e fr0m 1.5% t0 2.5% VR (F19. 3), We have extrap01ated th15 f1near 150t0pe trend t0 10wer matur1t1e5, h0p1n9 that 1t 15 ~50 vahd f0r matur1t1e5 6etween 0.6 and 1.5% VR (a1th0u9h we have n0 ev1dence ~0m the pyr01y~5 exper1ment). 7hat th15 extrap01at10n 0f the m0dd ~ ju5t1f1ed 5h0w5 a c0m- par150n 6etween natura1 9a5e5 ~0m Car60n1fer0u5 c0a15 0f NW 6ermany and the pyr01y~5 data (F19. 4). 7he ~0t0pe/matur1ty trend 0f (7) acc0unt5 very we11 f0r the 150t0p1c var1a61f1ty 0f u n ~ r e d c0M 9a5e5 fr0m NW 6ermany that are r d a ~ d t0

- 1 6 - -

• • . . . . - ° • "

- 2 8 - - ~

•

-32 1 1 1 1 [ 1 0 0.5 1.0 1.5 2.0 2.5 3.0

vR (%)

~9. • c0mp~50n 6etween the em~r1c~ m0dd ~ r c0~ 9a5e5 0f 8erner (198~ ~0m re5erv01r 9a5e~ and the em~r1c~ m0dd ~ 5 p a ~ der1ved ~0m pyr~y~5 ex~r1men~ 0f 1andp~nt m~er1~. ~ack ~rde5 and 54ua~5 are mea5u~d 1 ~ r~05 ~ me~ane a ~ ~Mne, ~ 5 ~ v e ~ ~0m c0~ 9 ~ 0f

~ 6 e ~ a n y ~ 8erne~ 1989 and ~ r ~ u ~ ~ted ~ e ~ .

Em~f1c~ ear60n 150t0pe]matur1ty re1at10n5h1p5 951

matur1t~5 6etween 0.6% and 2.0% VR (8erneL 1989). 7he 9raph 0f e4uat10n (7) 15 a150 very d05e (F19. 4) t0 the pref10uf1y 5u99e5ted emp1r1ca1 f1near 150t0pe/matudty m0dd 0f 8erner (1989). We there- f0re a55ume that the 1n5tantane0u5 m0dd 0f (7) 15 va11d 6etween 0.6% and 2.5% VR.

F0r pyr01yt1c ethane f 0 m h19her 1andp1ant5 we 065erve a f1near 1ncrea5e 0f ~0t0pe rat105 w1th 1ncrea51n9 matur1ty 6etween 0.6% and 2.5% VR. 7he ~0t0p1c var1at10n 0f 1n5tantane0u5 ethane can theref0re 6e de5cr16ed thr0u9h the emp1f1ca1 func- t10n

~211~ = 3.1987VR - 26.901

~0rre1at10n : ~ = ~9837) (8)

where ~ m 5tand5 f0r the car60n ~0t0pe rat10 0f ethane at a matur1ty VR ( 0 ~ - 2 5 % L A c0mpar150n w1th 150t0pe/matur1ty p~r5 0f ethane f 0 m c0M5 f 0 m NW 6ermany (8erner, 1989) 5h0w5 (F19. 4) a 5h1~ 0f 1% 6etween c0M 9a5e5 and pyr01y515 pr0- duct5 0f 8erner et aL (1995). H0weve~ the hnear c0rre1at10n 06t~ned f 0 m the ~hane/matur1ty p ~ 0f c0M 9a5e5 (8erne~ 1989) reveM5 the 5ame ~0pe a5 (8). 7h15 065ervat10n 5u99e~5 that the a55umed k1net1c ~0t0pe effect may 6e the 5ame f0r pyr01y515 ethane and ethane ~0m naturM c0a11f1cat10n pr0- ce55e5, 6ut that the 150t0p1c precur50r f1te5 w1th1n the Car60n1~r0u5 c0~5 and the xy11~ have d1fferent ~0t0p1c c0mp0~t10n5.

Car60n ~0t0p1c var1at10n 0f pr0pane f 0 m the pyr01yf15 exper1ment (8erner et a1., 199~ 5h0w5 n0n-hnear1ty w1th 1ncreaf1n9 matur1ty (F19. ~ 0.6% t0 1.8% VR). We acc0unt f0r the chan~n9 ~0pe 0f the ~3C-1ncrea5e 0f pr0pane thr0u9h a 3rd-0rder fun~10n

~31H1 = 4.903 VR 3 - 21.033VR 2 + 30.436VR - 3~164

(c0rre1at~n : ~ = 0.9782) (9)

where 6311n 15 the 1n5tantane0u5 car60n ~0t0pe va1ue 0f pr0pane 9enerated f 0 m h19her ~ndp1an~.

E4uat10n5 (7)-(9) refer t0 the 5pe~f1c re5u~5 0f the pyr01yf15 exper1men~ 0f 8erner et aL (1995~ and d0 n0t acc0unt f0r 150t0p1c var1a61f1ty 0f d1ffer- ent 7ype 111 precur50r5. 70 06t~n f0rmuhe that are 9enera11y app11ca61e 1n exp10rat10n, we have t0 add a term t0 the a60ve e4uat10n5 that c0rrec~ f0r d1fference5 0f the ~0t0pe rat105 0f the hndp1ant precur50~. 8erner et aL (1995) 5u99e5ted an 150t0- p1c c0mp051t10n 0 f - 2 2 % f0r the methane precur50r f1te5 w1th1n the x~1te 0f the 1a60rat0ry exper1ment, wherea5 the precur50r5 0f ethane and pr0pane may have 6een 5119hf1y dep1eted 1n ~3C (c0mpared t0 methane precur50r5) and can 6e5t 6e de5cr16ed thr0u9h 6~3C-va1ue5 0 f - 2 2 A % and -22.8%, re- 5pect1ve1y. Accept1n9 the5e v~ue5, we n0w can c0r- rect e4uat10n5 (7)-(9) f0r ~0t0p1c var1a61~ty 0f the

0 ~ a ~ c ~ n ~ 7he ~ a e n0w have the 9en- em1 ~

~n1 = ~nn + ~ 2 ~ - 1~m1]

~ ~ ~ , (1 ~

~ m = h~m + ~2.4 - [~nf1

( ~ 5 m n t ~ e ~ , (11)

~ . 1 = hm1 + ~2.8 - 1~11

( ~5mn~ne0u5 ~ a n ~ , (1 ~

where 6m den0te5 the 1~f1a1 car60n ~ 0 ~ p e rat105 0f ~ n d ~ a n t 9a5 precu~0~.

APPL1CA710N 0 F 7 H E M 0 D E L 5 1N CA5E 57UD1E5

W~h e4uat10n5 (4)-(6) we n0w have a 5et 0f f0~ mu1ae that can 6e u5ed f0r the the0ret1ca1 pred1ct10n 0f car60n ~0t0pe rat105 0f therm~ methan~ ethane and pr0pane 1n re1at10n t0 the matur1ty 0f mar1n~ a19a1 precur50r 5u65tance5. Add1t10na11~ e4uat10n5 (10)-(12) a110w the c~cu1af10n 0f car60n ~0t0pe rat105 0f therm~ methan~ ethane and pr0pane f 0 m 1andp1ant mater1~. 80th 5et5 0f e4uat10n5 can 6e u5ed t0 06t~n ~t3C-va1ue5 0f 1n5tantane0u5 9a5e5 1n the f0110w1n9 5ect10n we w111 pre5ent tw0 appf1cat10n5 0f 0ur m0dd5 that 5h0w the 6enef1~ and a150 the 11m1tat10n5 that mu5t 6e p1aced 0n the u5e 0f the5e e4uat10n5.

6a5e5 fr0m m~cene mar~e 50urce r0ck5 0 f the 6reen 7uf f 8a5~ (Japan)

7he 6reen 7uff 8a~n 0f NE Japan can 6e 5u6d1- v1ded 1nt0 tw0 5u6-6af1n5, the N119ata and Ak1ta 6af1n5, re5pect1ve~. 7he 50urce r0ck5 f0r hydr0ca~ 60n5 are mar1ne 61ack 5ha~5 0f the M1dd~- t0 Upper M10cene Nanatan1 and 7erad0mar1 F0rmat10n5 that c0nt~n am0rph0u5 ker09en5. 0ccurrence5 0f 01~ and c0nden5ate5 that are a~0d- ated w1th 9a5e5 p01nt t0 d1fference5 1n the matur1ty 0f the 50urce r0ck5 5akata (1991) pu6115hed car60n ~0t0pe rat105 0f natura1 9a5 methan~ ethane and pr0pane fr0m d1fferent 011 and c0nden5ate re5er- v01r5. H0wever, 5akata (1991) wa5 n0t a6~ t0 exp1a1n 5uff1~enf1y the d15crepan~e5 6etween car60n ~0t0pe rat105 0f 9a5e0u5 hydr0car60n5 0f the 6reen 7uff 8af1n and th05e pred1cted f 0 m d1ver5e m0dd5 a v ~ h 6 ~ at the t1me 0f pu611cat10n.

0ne e55ent1a1 parame~r f0r the app1~af10n 0f 0ur m0dd5 15 the 313C-v~ue 0f the 0r9an~ precu~0r 0f the 9a5e5. A 5uff1denf1y c0rrect appr0~mat10n 0f the ~0t0p1c c0mp0f1t10n h r9dy determ1ne5 the 4ua11ty 0f the pred1ct10n. 1n th15 5pe~f1c ca5e, we d0 n0t kn0w the car60n 150t0pe rat10 0f the M10cene 61ack 5h~e5 0f Japan. F0r 0ur ca1cu1at10n5 we have

952 U1r1ch 8erner and Eckhard Fa6er

- 1 0 - (a)

A • ~D -2~ --

M ~ 9 ~ 6ac~f1M m~hane

-30 -- • • •

•

-35 1 1 1

M0de1

01101ffC0nde~ e ~ C ~ ~ 1 ~ 2.2 C 0 n d e ~ e ~ 2.0 /

~ ~ 1•6VR (%)

~ 1 D ~ a : 5akata, 19911

-60 -55 -50 -45 -40 -35 -30 -25 -20 -15

~ 1~Methane (0/~)

(0) 2.0 .-•"

1.6 ,-" " ~ VR (%) ~

•

1.0 -" ~ -- ~ .0"

--~8~-~~ ~ " " 16reen7uff8af1mjapan 1

-30 -25 -10 -15

-16 --

-18 --

-20 --

-22

-24

-26

-28

-30 -35

~ 13CEthane (°]00)

F19. 5. 150t0pe/matur1ff m0dd5 ~ c0mpar150n w1th car- 60n ~0t0pe rat105 0f 9a5e5 0f the 6~en 7uff 8a~n ~apan). (a) 1n5tantane0u5 m0dd5 f0r p~r5 0f m~hane and ~hane; (6) 1n5tantane0u5 m0dd5 f0r p~r5 0f ethane

and pr0pane.

e5t1m~ed the 6 ~ 0f the am0~h0u5 and f1kdy mar1ne der1ved ~ r 0 ~ n 5 0f the 6 ~ e n 7uff 8a~n t0 ~ ~ m th05e d e p 0 ~ d at the 5ame t1me ~ the M0~erey 8a~n ~ 0 ~ h Amer1c~. U~n9 a ~ v ~ u e 0 f - 2 3 % ~ 0 rL 198~, we p r e ~ ~ a ~ a n e 0 u 5 ~ 0 ~ p e rat105 0f m~han~ ethane and pr0pane ~0m e 4 u ~ n 5 ~ , (5) and ~ , re~ect1ve~ ~ 9 5 5a and ~.

1t ~ 06f10u5 that mea5ured hm0pe data 0f m~hane p a ~ y def1~e ~ a ~ y ff0m the c~cu- ~ d v ~ u ~ . H0weveL ~ 0 p e v~ue5 0f ethane 0f 0f1-a550~ated 9a5e5 p ~ m t0 m~ur1t1~ 0f 0.6% t0 0.85% VR, wherea5 9a5e5 that are a ~ 0 ~ a ~ d ~ t h ~xmre5 0f ~ and c0nden5a~ 0r c0nden5ate H0ne 5 u 9 ~ m~ur1t1~ 6~ween 1.1% and 1.6% VR ~ 9 . 5~. 1t ~pea r5 that car60n ~m0pe rat105 0f ~hane, 6ut n0t m~han~ f1t t0 the expec~d m ~ u v ky trend. A5 ~ready pr0p05ed 6y 5akata (1991) t~5 def1at10n 0f m~hane ~ 0 ~ 5 ff0m t ~ m0dd mwa~5 v~ue5 that ~ c ~ e an e n ~ h m e m 0f ~2C ~ 9 . 5~ can 6e e x ~ n e d 6y an ~ u r e 0f 6ac- ~r1~ m~hane t0 therm~ 9a~5. At ~a5t ~ r the c0nden5ate a ~ 0 ~ a ~ d 9a~5 we 065erve a ~ n 9

trend w1th a 9r0up 0f therm~ endmem6er5 fa111n9 0n the matur1ty f1ne (F19. 5a).

Fr0m car60n ~0t0pe rat105 0f ethane and pr0- pane ~ appear5 that 011 a550dated 9a5e5 were 9ener- ated ~0m 50urce r0ck5 that have reached matur1t1e5 1n the 011 w1nd0w 6etween 0.6% and 0.85% VR (F19. 56). H0wever, the matur1ty v~ue (F19. 56) ~0m 150t0pe rat105 0f ethane 0f 0f1/c0nden5ate and c0nden5ate a550c1ated 9a5e5 r e h ~ d t0 the 1naan- tane0u5 m0de1 are h19her (1.1% t0 1.6% VR) than th05e ~0m ~0t0pe5 0f pr0pane (1.0% t0 1.3% VR). 06v10u~y the 9a5e5 ~0m 50urce5 0f a pre5umed h19her matur1ty dev1ate ~0m the 1n~antane0u5 m0de1 t0ward5 h19her ethane ~0t0pe va1ue5. We 5u99e5t that th15 phen0men0n 15 r d a ~ d t0 m1~n9 0f 9a5e5 ~0m 50urce5 0f d1fferent matur1t1e5, a5 w0u1d 0ccur when 9a5e5 accumu1ate 0ver a hr9er matur1ty ran9e 0f the 50urce r0ck.

A1th0u9h the e5t1mate5 ~0m 0ur m0dd 100k c0n- v1n~n~ we 5u5pect that the m0dd appr0ach can 6e ~9n1f1cant1y 1mpr0ved when mea5ured car60n 150- t0pe va1ue5 0f the am0rph0u5 ker09en5 are av~1- a61e.

6a5e5 fr0m Perm1an c0a• 0f the C00per 8a5• ( Au~ra11a)

7he C00per 8a~n w1th ~5 Perm1an c0a1 mea5ure5 15 0ne 0f Au5~a11~5 m05t pr011f1c hydr0car60n area5 w1th re5erv01r5 that c0nt~n 9a5e5 wh1ch are a550dated w1th 0115 0r c0nden5ate5 (R196Y and 5m1th, 1981; Kan5f1er et a1., 1983). 1t c 0 n ~ 5 0f three m~0r ~0u9h~ 0f wh1ch the cen~a1 NE-5W ~end1n9 Nappamerr1 7r0u9h 15 the d0m1nant de- pre5~0n (Kan5t1er et a1., 1983), where matur1t1e5 0f the 50urce r0ck5 can reach m0re than 2% VR (F19. 6). Pr0duct1ve re5erv01r5 are f0und 1n area5 where the matur1t1e5 0f the 5ed1mentary r0ck5 d0 n0t exceed 2% VR (F19. 6).

Car60n ~0t0pe rat105 0f methane and ethane 0f n1ne 9a5e5 c011ec~d fr0m pr0du~n9 hydr0car60n re5erv01r5 and D57•5 are 5h0wn 1n F19. 7 050t0pe data fr0m R196y and 5m1th, 1981; matur1t1e5 fr0m Kan5f1er et a1., 1983, c0mpare F19. 6). 7he 150t0p1c var1at10n 0f the C00per 8a~n 9a5e5 wa5 a~r16uted t0 chan9e5 0f the 50urce r0ck9 matur1t1e5. 7he type 0f 0r9an1c mat~r 15 a55umed t0 6e 0f 1andp1ant 0ff- ~n (R196y and 5m1th, 1981). H0wever, Kan5f1er et aL (1983) 5tate that 50urce r0ck 4ua11ty may 6e 10ca11y enhanced thr0u9h e~n1te 0r 6acter1aHy de9raded p1ant t155ue~

70 te5t the a~umpf10n5 0f R196y and 5m1th (1981L we app11ed th~r e4uat10n5 (19) and (21) t0 pred1ct 1n5tantane0u5 ~0t0pe rat105 0f 9a5e5 fr0m h19her 1andp1ant5 0f the C00per 8a~n. 7he avera9e car60n ~0t0pe va1ue 0f 0115 and c0nden5a~5 ( -24%) 0f the C00per 8a~n (a~er R196Y and 5m1th, 1981) 5u99e5t5 that the terre~r1~ 0r9an1c matter may have a 6~3C 0 f - 2 3 % , a5 f14u1d hydr0- car60n5 are u5ua11y dep1eted 1n ~3C 6y 1% c0m-

Em~f1c~ car60n ~0t0p~matuf1~ rdat10n5~p5 953

NW 0

1 0 0 0 -

m-

4•00

~ 7R~K R1~E

04n111 : 5EA LE¥~L

~ R R A 7 R ~ H

CU7~RR~

NAP~M~R1 ~ N A ~ A 7 ~ 7 ~ H

~ n m U ~ ~6 t ~ 5 ~ 1 5E

~ C R E ~ ~ • ~E1

" ~ ~ - - - - - - - ~ - - - - ~ - - - - - - - - -- 0 .50

/ ~ . ~

~ ~ . ~

~ - ~

----~10---- V1~1~ 1~F1EC~

F19. 6. Cr0~ 5ect10n 0f the C00per 8a~n (Au5tra11a) w1th ~0-matuf1ty f1ne5 (m0d1f1ed after Kan5f1er et a1., 1983L 0pen (dry 9a5e5) and f111ed (011 a~0c1a~d) 5tar5 mark 5amp11n9 depth (D57 a ~ re5erv~.

pared t0 thdr precur50r. F0110w1n9 C1ayt0n•5 (1991) ar9umenL 9a5 precur50r5 0f terre5tr1a1 p1an~ (51de ch~n5 0f ar0mat1c 5tructure5) are n0rm~1y ~0t0p1- c~1y ~9hter than the ar0mat1c 9r0up5 0f the ~9n1n. 70 acc0unt f0r the5e d1fference5, we u5e 1n 0ur c~- cu1af10n5 an 1n1t1a1 150t0pe rat10 0f 9a5 precur50r5 0f -25%, 5u99e5t1n9 an 0ff-5et 0 f - 2 % ~0m the 150- t0pe rat10 0f the 0r9an1c mat~r.

We 065erve that the 9a5e5 0f the C00per 8af1n de~ate ~0m the pred1cted 1n5tantane0u5 ~0t0pe rat105 (e4uat10n5 (10) and (11~ 0f 9a5e5 ~0m h19her 1andp1an~ (F19. 8) t0ward5 h19her ~C c0ncen- trat10n5. 7he de~at10n 5u99e5~ m1x1n9 6etween a terre5tr1a1 50urce and a 5ec0nd c0mp0nent 0f 0ther 6acter1a1 0r therm~ 0r1~n, the 1atter 9enerated ~0m e~n1t1c 0r9an1c matter when we f0~0w the 5u99e5t10n5 0f Kan5f1er et aL (1983). 70 acc0unt f0r th15 hyp0thef15 we have cMcu1ated 1n5tantane0u5 car60n ~0t0pe rat105 f0r methane and ethan~ a55um1n9 an 1n1t1a1 ~0t0pe rat10 0 f - 2 5 % f0r the ex1n1te, app1~n9 e4uat10n5 (4) and (5). Fr0m the c0mpar150n 0f m0dd5 and mea5ured ~0t0pe rat105 1t appear5 that 9a5e5 p10tt1n9 d05er t0 the terre5tr1a1 ~ne can 6e exp1~ned thr0u9h 9enerat10n ~0m hum1n1t1c precur50r5, wherea5 5amp1e5 d05er t0 the ~ne 0f 9a5e5 ~0m e~n1t1c 5u65tance5 may 6e exp1~ned a5 5uch. 6a5e5 p10tt1n9 1n6etween the matur1ty ~ne5 can 6e exp1a1ned a5 m1xture5 0f the tw0 50urce5 (F19. 8).

06~0u51~ what 100ked a5 0ne f1n~e matur1ty trend 1n F19. 7, n0w can 6e 1nterpre~d a5 tw0 d1fferent 0ne5, rdamd t0 tw0 d1fferent type5 0f 0r- 9an1c precur50r5 (F19. 8). 1ntere5t1n91y, pred1c~d matur1t~5 0f ex1n1t1c precur50~ match the matur1- t1e5 that 0ccur at the depth ~ v d at wh1ch the 5amp1e5 were c01~cted. 7he 5amp1e5 ~0m 5tr2e1eck1 3 (0.7% VR) and Merf1md1a are a~0~ated w1th 011

wherea5, D57 5amp1e5 ~0m Cuttap1rr1e 1 (1.1% VR) and 7001achee 9 (1.2% VR) are n0t a5- 50~ated w1th 011 (Kan5f1er et a1., 1983). 7he c0rre- ht10n 6etween ca~u1ated and mea5ured matur1t1e5 5u99e~5 that the 9a5e5 were 9enera~d ~0m 50urce5 that 0ccur at the depth ~vd at wh1ch the 5amp1e5 were c011ec~d. F0r 9a5e5 that pre5uma61y were 9en- erated ~0m a m0re hum1n1t1c 50urce (Merr1me11~ 819 Lake and M00m6a) we 065erve (F19. 8) that 0ur m0de1 pred1ct5 a 10wer matur1ty w1th1n the 011- w1nd0w f0r Merr1mdh (011-a550da~d 9a5 and mea5ured VR 0f 0.9%, Kan5f1er et aL, 1983) wherea5 the 9a5e5 ~0m 819 Lake and M00m6a (n0t a550c1ated and mea5ured VR 6etween 1.8 and 2.0%, Kan5f1er et a1., 1983) are pred~ted t0 c0me ~0m 50urce5 6ey0nd the 011-w1nd0w. 7he p00r re501ut10n 0f the h n d p h n t m0dd d0e5 n0t a~0w a deta11ed

-20

-24 - - • •

•

• •

Merf1md1a 700~chee

- - e

Cm~rr1e 5tr2e1eck1 •

-40 -- •

-44 1 1 1 1 1 0 .5 0 . 7 0 . 9 1.1 1.3 1.5

VR (%)

-28

~ -32 2

- -36

• •

M00m6a• 5 •

819 L a k e

• • MethaneEthane 1

1 1 L

~.7 1.9 2.1

F1~ 7. Car60n 150t0pe rat105 0f m~hane and ethane ~0m 9a5e5 0f the C00per 8a~n (Au59a11~ v5. m~uf1~ 0f 0r-

9a~c m ~ r (VR %) ~ 5ampf1n9 depth.

954 U1f1Ch 8erner and ECkhard Fa6er

15 -

-20

-25

% ~ -30

~ -35 %

-40

-45

-50

N~a55°d~edA55°c~d ~ 1 2.6 //2.4

VR111 (%~0~6 ~ ~ 0 / ~ ~ / / 1 , 6 VR11 (%)

//1.2 ~ ~ ~ 1.2

"-0.6---------~7 ~ ,., • 1

-35 -30 -25 -20 15 - 10

~13CEthane (~]~)

-40

F19. 8. 1n~antane0u5 ~0t0pe/matuf1ty m0deh f0r 9a5e5 0f 7ype 11 and 7ype 111 50urce r0ck5 app11ed t0 9a5e5 0f the C00per 8a~n (Au5~a11a).

pred1ct10n 0f matur1t1e5. D1fferent ~0m the a55umpt10n5 0f R196y and

5m1th (1981), 0ur m0de11n9 5u99e5t5 that 150t0p1c vaf1a61f1ty 0f C00per 8af1n 9a5e5 15 0n1y part1y 1nduced 6y matur1ty. 7he m~n 5h1~ 0f car60n 150- t0pe rat105 15 hkdy t0 6e rdated t0 d1fference5 6etween 0r9an1c precur50r5 (hum1n1t1c v5. e~n1t1c). H0wever, 0ur m0dd can 6e 519n1f1cant1y 1mpr0ved thr0u9h 1nc0rp0rat10n 0f mea5ured ~13C-v~ue5 0f 9a5 precur50r~ 1n5tead 0f uf1n9 appr0~maf10n5.

hydr0car60n5, the m0dd5 can 6e ~9n1f1canf1y 1mpr0ved when mea5ured ~0t0pe rat105 0f the 9a5 precur50r5 are u5ed 1n the ca1cu1af10n5.

Ackn0w1ed9emen~--7he auth0r5 are 9ratefu1 t0 W. 5tah1 and A. H01~r6ach f0r d15cu5~0n5 and 5u99e5t10n5 that 1mpr0ved the m0dd5 at d1ver5e ~a9e5 0f th0r devd0p- ment. We M50 thank M. A. R00ney and J. R. 60rm~ f0r c0n5truct1ve ~f1ew5 0f 0ur paper. 7he w0rk 0f U. 8. wa5 f1nanc1a11y 5upp0rted thr0u9h 8MF7-6rant 0326686D.

C0NCLU510N5

~0t0pe/matUr1ty m0dd5 f0r methan~ ethane and pr0pane Were 06t~ned ~0m an app1~at10n 0f 5tat- 15f1c~ curve-f1tt1n9 pr0cedure5 t0 the re5u1~ 0f 1n- 5tantane0u5 k1net1c m0dd5 6a5ed 0n re5u1t5 0f pyr01y~5 exper1men~ that ~ m u ~ p~mary crack- 1n9. 7he ~mp1e emp1r1c~ e4uat10n5 re1ate car60n 150t0p1c var1at10n5 0f ~9ht hydr0car60n5 d1rect~ t0 50urce r0ck matur1ty and car60n ~0t0p1c va~a61~ty 0f the precur50r5 and can 6e app~ed where 9a5e5 have a c c u m u ~ d 1n5tantane0u51y.

App11cat10n 0f the m0d~5 t0 9a5e5 ~0m the 6reen 7uff 8a~n 0f Japan (data ~0m 5akata, 1991) 5h0w5 a remarka61e c 0 ~ a t 1 0 n 6etween pre- d~ted matu6ty 0f the mar1ne 50urce r0ck5 and the a550~at10n 0f 9a5e5 w1th 0115 and c0nden5ate5 a5 an 1nd~at0r 0f the matur1ty.

6a5e5 0f the C00per 8a~n 0f A u ~ r ~ (data ~0m R196y and 5m1th, 1981) are da5~f1ed thr0u9h 0ur m0dd a5 9a5e5 ~0m hum1n1t1c and e~n1t1c pre- cur50r5. 1ncrea~n9 matur1t1e5 0f the 50urce r0ck5 are expre55ed thr0u9h 1ncrea51n9 ~3C 0f methane and ethane.

A1th0u9h 0ur c~cu1at10n5 pr0v1de a 5at15fy1n9 ex- p1anat10n t0 the mea5ured ~0t0pe rat105 0f 119ht

R E F E R E N C E 5

8erner U. (1989) Entw~k1un9 und Anwendun9 emp1r1- 5cher M0de11e ff1r d~ K0h1en5t0ff150t0penvar1at10nen 1n M15chun9en therm09ener Erd9a5e. Ph.D 7 h e ~ 7ech. Un1v. C~u~h~, 162 pp.

8erner U., Fa6er E. and 5tah1 W. (1992) Mathemat1ca1 ~mu1at10n 0f car60n 150t0p1c ffact10nat10n 6etween hum1n1t1c c0a15 and re1ated m~han~ Chem. 6e0L 94, 315 319.

8erner U. and Fa6er E. (1993) 2u5ammenf~hrun9 und W0~rentw1ck1un9 ~0t0pen9e0chem15cher Meth0den 1n der Exp10rat10n v0n K0h~nwa~er~0ffen. 86R-Rep0~ Fed 112 083, 1n5t. 6e05c. Nat. Re5. Hann0ve~ 48 pp.

8erner U., Fa6er E., 5cheeder 6. and Pan~n D. (1995) Pr1mary crack1n9 0f a19~ and hndphnt ker09en~ K1net~ m0dd5 0f ~0t0pe var1at10n5 1n m~han~ ethan~ and pr0pane. 1n Pr0ce55e5 0f Natura1 6a5 F 0 r m a t ~ (Ed1~d 6y R1ce D. D. and 5ch0d1 M.). Chem. 6e0L 12~ 233-245.

Chun9 H. M., 60rm1y J. R. and 54~re5 R. M. (1988) 0f1~n 0f 9a5e0u5 hydr0car60n5 1n 5u65urface env1r0n- ment5:7he0ret1ca1 c0n~derat10n5 0f car60n 150t0pe d15- tr16ut10n5. Chem. 6e0L 71, 97-103.

Chyt0n C. (1991) Car60n h0t0pe ffact10nat10n dur1n9 natura1 9a5 9enerat10n ~0m ker09en. Mar. Pe~0L 6e0L 8, 232-240.

Fa6er E. (1987) 2ur 150t0Pen9e0chem~ 9a5f6rm~er K0h~nwa55er5t0ffe. Erdd1, Erd9a5, K0h• 10~ 210-218.

6M1m0v E.M. (1988) 50urce5 and mechan15m5 0f f0r- mar10n 0f 9a5e0u5 hydr0car60n5 1n 5ed1mentary r0ck5. 0r1~n5 0f Methane 1n the Ea~h. Chem. 6e01. 71, 77-95.

Em#f1cM car60n ~0t0p~mMuf1~ re1at10n5h~5 955

Jame5 A.7. (1990) C0~daf10n 0f ~ r v ~ r e d 9a5e5 u51n9 the car60n 150t0~c c0mp0~f10n5 0f wet 9a5 c0m- p0nent~ AAP6 8u~ 74, 1441-145~

Kan5f1er A. J., Prudence 7. J. C., C00k A. C. and 2w19u115 M. (1983) Hydr0car60n ha~mt 0f the C00pe~ Er0man9a 8a~n, Au~r~1a. 1n Petr01eum 6e0chem15try and 8a5~ Eva~at~n (Ed1ted 6y DemM50n 6. and Murf15 R. J.L AAP6 Mem01r 35, 373-390.

Le~haeu~r D. and 5chae~r R.6. (198~ D1ffu~0n ~edf1~ m0~kuh~r K0h~nwa5~r5t0ffe du~h den P0~nraum 5ed1men~r 6~t~ne . M~t. 6e0L -Pa1~0nt, 1n5t. Un~. Ham6ur9, Fe5~and 6ec r9 Knet5ch 56, 287-306.

0 ~ W. L. (198~ K~09en~5phM~ne~dfur ~ t10r5~p5 M 5u1fu~6ch M0nterey 0115. 1n: Advanc~ M 0r9~n~ 6e0chem~try 1985 (Ed1ted 6y Leythaeu5er and Ru11k6tte), pp. 499-516. Per9am0~ 0xf0rd.

~n9 5. and Y0n9chan9 X. (198~ Chara~ef12at10n 0f the car60n and hydr09en ~0t0#c c0mp051t10n ~ naturM 9a5e5 fr0m c0nt1nent~ ~ m e n t 5 ~ C~na. Academ~ 5 ~ ¢ 185-199.

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R00ney M. A., C1ayp0~ 6. E. and Chun9 H. M. (199~ M0de11n9 therm09en1c 9a5 9enerat10n uf1n9 car60n 150- t0pe rat105 0f natura1 9a5 hydr0car60n5. 1n: P r 0 c e ~ 0f Natur~ 6a5 F0rmat10n ( E ~ d 6y R1ce D. D. and 5ch0e11 M.~ Chem. 6e0L 12~ 219-232.

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