kerogen, thermal maturity, crude oil inclusions, & pyrobitumens in bowser and hazleton group,...
TRANSCRIPT
Kerogen, thermal maturity, crude oil inclusions, & pyrobitumens in Bowser
and Hazleton Group, Bowser Basin, B.C.
L.D. Stasiuk and N.S.F. WilsonNatural Resources Canada
Geological Survey of Canada: Calgary
Purpose of todays presentation: kerogen (source rocks?), thermal maturity, distribution of crude oil-bitumen-
pyrobitumen, temperatures, paragenesis etc.
Review of most current petrology (organic & sedimentary)data collected at GSC Calgary in Bowser
Review (briefly) previous thermal maturity data from BowserBasin (Evenchick et al , 2002)
Methods
Organic Petrology: Reflected white and fluorescent light microscopy
Sedimentary Petrology: Transmitted & reflected light – fluorescence microscopy, fluid inclusion microthermometry
Organic Geochemistry – Rock Eval, biomarkers (?)
Samples in this study
Ritchie wells 56.417oN, 129.962oWRock Eval – TOC
010002000300040005000600070008000
0.0 0.5 1.0 1.5 2.0 2.5 3.0
Total Organic Carbon - wt %
Dep
th (
ft)
Ritchie A-3-JRitchie C-62-G
Bowser Gp ?
Hazleton Gp ?
Source rock ?
Rock Eval – kerogen type Ritchie wells 56.417oN, 129.962oW
0
100
200
300
400
500
600
700
800
0 50 100 150 200
(OI (mg CO2/g TOC)
HI (
mg
HC
/g T
OC
)
Ritchie A-3-J
Ritchie C-62-G
Type I
Type II
Type III
Terrestrial-dominated macerals in kerogen: deltaic, marine influence,
Ritchie wells 56.417oN, 129.962oW
Ritchie A-3-J, 2115-2960’,Bowser and uppermost Hazleton ?
Terrestrial-dominated macerals in kerogen: deltaic, marine influence
Ritchie A-3-J, 2115-2960’,Bowser and uppermost Hazleton ?
Probable potential SPENT source rock: marine kerogen precursor ?
Ritchie A-3-J, Hazleton Group ? Lower Jurassic6745’, TOC = 2.4 %
Equivalent to Nordegg of Alberta ??
Spent amorphous kerogen
Rock Eval – S1 and S2
0100020003000
40005000600070008000
0.00 0.05 0.10 0.15
S1 (mg Hcarbons/g Rock)
Dept
h (fe
et)
Ritchie A-3-J
Ritchie C-62-G
010002000300040005000600070008000
0.00 0.05 0.10 0.15 0.20
S2 (mgHcarbons/g Rock)
Dept
h (fe
et) Ritchie A-3-J
Ritchie C-62-G
Thermal maturity of Bowser and Hazleton groups – Vitrinite %Ro
0
1000
2000
3000
4000
5000
6000
7000
8000
0.5 1.5 2.5 3.5 4.5 5.5 6.5 7.5 8.5
Vitrinite %RoRandom
Dep
th (
feet
)
Ritchie A-3-J
Ritchie C-62-G
cond-drygas
dry gasrare
Bowser ?
Hazleton ?
~ 270-290 oC
Pyrobitumens – early high %Ro and late low %Ro
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
0.5 1.5 2.5 3.5 4.5 5.5 6.5 7.5
Isotropic pyrobitumen %RoRD
epth
(fe
et)
Ritchie A-3-J
Ritchie C-62-G
cond-drygas
dry gasrare
Bowser ?Hazleton ?
~ 180-190 oC
~ 270-290 oC
Late ‘low’ maturity pyrobitumens in Ritchie C-62-G
Ritchie C-62-G, late low %Ropyrobitumen in fractures, 7235’
Ritchie C-62-G, late highly anisotropic pyrobitumen in late calcites,
9699.6’
~ 180-190 oC
Late - high maturity crude oil inclusions in Ritchie A-3-J, 2115.7’
803-2002
Ritchie A-3-J, late crude oil inclusions in calcite and fractures, 2115.7’’
Ritchie A-3-J, late crude oil in intercrystalline areas in quartz
cement, 4723.4’
Ritchie A-3-J, late crude oil in in calcite cement, 6745.0’
Late - high maturity crude oil (condensate) inclusions in Ritchie
Ritchie A-3-J, 2115.7'
0
20
40
60
80
100
420 470 520 570 620 670 720
Wavlength (nm)
Inte
ns
ity
Ritchie A-3-J, 4337.0'
0
20
40
60
80
100
420 470 520 570 620 670 720
Wavelength (nm)
Inte
ns
ity
Ritchie A-3-J, 4723.4'
0
20
40
60
80
100
420 470 520 570 620 670 720
Wavelength (nm)
Inte
ns
ity
Ritchie A-3-J, 6745
0
20
40
60
80
100
420 470 520 570 620 670 720
Wavelength (nm)
Inte
ns
ity
35-45 oAPI
> 45-55 oAPI
redgreenblue
Late - high maturity crude oil and condensate inclusions in Ritchie A-3-J.
0
1000
2000
3000
4000
5000
6000
7000
8000
420 470 520 570 620
Wavelength (nm)
De
pth
(ft
)
condensate
condensate - oil
crude oil - low density
> 35-50/55 oAPI
> 50-55 oAPI
Tango Creek Formation
Bowser Lake Group
Late - high maturity crude oil inclusions in Muskaboo Creek Fm, Bowser Lake Group
Muskaboo Creek outcrop,
57.56oN, 129.96oW
0
20
40
60
80
100
420 470 520 570 620 670 720
Wavelength (nm)In
ten
sit
y > 55 oAPI
Late pyrobitumen in Muskaboo Creek Fm, Bowser Lake Group, Muskaboo Creek
outcrop, 57.56oN, 129.96oW
%RoRmean = 1.20, ~ 150oC
Pyrobitumen:%RoRmean = 1.58
Late - high maturity crude oil inclusions and late pyrobitumen, Bowser Lake Group,
57.441oN, 128.572oW, outcrop
Crude oil inclusions
Host rock has a thermal maturity level of ~ > 3.6 %Rovitrinite (>240oC). Late pyrobitumen altered to ~ 160-165oC
Late - high maturity crude oil inclusions, Bowser Lake Group, 57.441oN, 128.572oW, outcrop
0
20
40
60
80
100
420 470 520 570 620 670 720
Wavelength (nm)
Inte
nsi
ty> 50-55 oAPI
Tango Creek Group: Sustut, 57.509oN, 128.814oW
0
20
40
60
80
100
420 470 520 570 620 670 720
Wavelength (nm)
Inte
nsi
ty
Late - high maturity crude oil inclusions, Tango Creek Fm, Sustut Group, 57.709oN,
128.814oW, outcrop
> 50-55 oAPI
Late pyrobitumen: 1.91 %Ro, ~ 170-180 oCEarly pyrobitumen: 5.55 %Ro, ~ > 250oC
Crude oil inclusions
Evenchick et al., GSC Open File 4343, 2002
572475 6275547 94d12EP92-133.0 2.85 CHECK 1.64573161 6275910 94d12EP92-135.0 2.56 CHECK 1.67574135 6276192 94d12EP92-138.0 3.07 CHECK 2.17
UTM_East UTM_North NTSStation_Text vitrinite-%Ror vitrinite-%Romax_sdvitrinite-%RominBit1Conversion
443700 6312640 104a13EPC92-503.0 1.96 CHECK 1.31499932 6297537 104a14EPC92-510.0 2.07 1.98499592 6295700 104a14EPC92-513.0 1.99 CHECK 1.38
Tango Creek Formation
Bowser Lake Group