Page 116 - The Petroleum System From Source to Trap

110 Peters and Cassa

HYDROGEN WELL HYDROCARBON
INDEX INDEX DATA INDICATIONS
DEPTH . DEPTH
' '
,.:. : i : � : i MUD fiEI ij IIODIClMI
INOD
I I I' "'�
15,1 TOC)IOO ��� LOG S , .. wr I � I
FEET ROC�YAL ' IOCIC-fAL
1
. . . . J ! '
GAS
';1
1 i5 1 11J I ·� ·� ·� ·�
1000
' - - - - , - � - � 500
-;·- - r - + '
I
I : �
JOOO
1000

ISOO
. . , '
.,
. '
- - - - - - ._�_
"
•
2000
')
.·�
2500

lOCO

3500

4000

4500

5000
S, =HCS ALREADY IN ROCK S2 =HCS FROM KEROGEN PYROLYSIS. S3 =C02 FROM KEROGEN PYROLYSIS.

Figure 5.1 1 . Geochemical log for well VIII shows the effects of a major thrust fault at about 2000 m in this well on T max• R0,
and Pl. The footwall shows good quantities of mature, gas-prone to inert organic matter, while the hanging wall contains
post mature organic matter. Sidewall cores indicated by dotted bars, drill cuttings by solid bars.

section for the fictitious Deer Shale source rock. graben formed on the right (east) side of the cross section
The fictitious Deer-Boar(.) petroleum system was during the Tertiary. To elaborate on this example, four
introduced by Magoon and Dow (Chapter 1 , this source rock maps and one cross section (Figure 5.12) that
1
volume) through four figures and a table (Figures . 2-15 represent the present-day geology show how a source
and Table 1.4). The map and cross section were drawn to rock is evaluated and placed into the context of a
show the essential elements of the petroleum system at petroleum system that was operating in late Paleozoic
the critical moment, or at the end of the Paleozoic. At that time. Sedimentary basin analysis techniques are used to
time, the Deer Shale was an active source rock, whereas evaluate the source rock, whereas the petroleum system
now, because of uplift, it is inactive. In addition, a rift is used to evaluate the hydrocarbons.