Basin and Petroleum System Modeling in the Los
Angeles Basin, California
Lauren Schultz
Basin and Petroleum System Modeling Group (BPSM)
Introduction
• Education
• Washington and Lee University ‘13• B.S. Geology, German minor
• Senior Honors Thesis: Sequence Stratigraphic and Structural Interpretation, Modeling and Restoration in the National Petroleum Reserve in Alaska (NPRA)
• Stanford University• Advisor: Steve Graham, Basin and Petroleum System
Modeling Group
• Current work: Basin and petroleum system modeling of the Los Angeles Basin, California
• Basin and Petroleum System Modeling Group (BPSM)
Outline
• Basin Background• Structure
• Stratigraphy
• Petroleum System
• Recent/Active Work• Data Collection and Digitization
• 1D Basin Modeling
• Future Plans
Project Goals
• Create 1D and 2D Petromod models of L.A. Basin
• Incorporate wide variety of available subsurface data, including formation tops, ages, lithology, TOC, etc. and calibration data, including pressures, temperatures and vitrinite reflectance
• Better understand unique L.A. Basin Petroleum System• Geochemical diversity of oils
• Role of structural evolution of basin in traps
Los Angeles Basin Background
Edited from Biddle, 1991
• Strike-slip basin, formed in Neogene (Wright, 1991)
Luyendyk et al., 1980Biddle, 1991; Crowell, 1974
Los Angeles Basin Background
Yerkes et al., 1965
Basement Structure
NW trending synclinal depression near center of basin, as deep as 31,000 ft below sea-level
N
Yerkes et al., 1965
Basement Structure
NW trending synclinal depression near center of basin, as deep as 31,000 ft below sea-level
N
Deep NW trending trough
Depth to Basement
• Newport-Inglewood deformation zone cuts through eastern part of basin, separating southwestern and central blocks• 3000-5000 ft right-lateral displacement for faults in
deformation zone
• Active since late-middle Miocene
• Whittier fault zone cuts through basin to the West, separates central and northwestern blocks• ~15,000 ft net right-lateral displacement
• Active since Miocene
• Series of east-trending faults form boundary between Transverse Ranges and Peninsular Ranges
Yerkes et al., 1965
Structural Features
Yerkes et al., 1965
Yerkes et al., 1965
Yerkes et al., 1965
Yerkes et al., 1965
Shaw and Shearer, 1999
Puente
Lower Fernando
Upper Fernando
Stratigraphy
Beyer, 1995
• Source rocks are middle to late Miocene, include Monterey, Modelo and Puente Formations• TOC as high as 10-16%
• Miocene-Pliocene submarine fan sands form important reservoir units• Include Fernando, Pico and Repetto
Fm sands
Jeffrey et al., 1970
Petroleum Background
• Rapid accumulation of sediment in deep (1600+ feet), cool water, as well as poor circulation resulted in excellent preservation of organic matter (Yerkes et al., 1965)
• Long history of oil exploration and production, first oil discovered 1880 (Barbat, 1958)
(Yerkes et al., 1965)
Mo
lass
e
Mag
alle
nes
Vie
nn
a
Pers
ian
Gu
lf
Hyd
roca
rbo
n P
rod
uct
ivit
y(1
00
0 O
EB/C
U M
I To
tal S
ed
)
Individual Basins0
200
400
600
4000
L.A. Basin Petroleum Background
LA Basin Petroleum Province
• Roughly triangular in shape, covers ~2200 mi2
• Assessed in 1995 by USGS NOGA
• Estimated 1.4-5.6 BBO undiscovered reserves still in Basin (Gautier et al., 2012)
Beyer, 1995
980 1610 60
L.A. Basin Petroleum Background
LA Basin Petroleum ProvinceL.A. Basin Oil Geochemistry
Project Objectives
• Collect relevant data, including archiving historical data
• Create 1D and 2D Petromod models of L.A. Basin
• Incorporate subsurface data, including formation tops, ages, lithology, TOC, etc. and calibration data, including pressures, temperatures and vitrinite reflectance
Current Work
• Field trip with Rick Behl to view Monterey Fmoutcrops in LA Basin• Collected phosphatic source rock sample for possible
kinetics analysis
• LA Basin Overview field trip with Ray Ingersoll
Current Work: Field Observations
Current Work
Base of Upper Miocene Structure MapCreated by Tom Wright
Current Work
Base of Upper Miocene Structure MapCreated by Tom Wright
• Cuts through depocenter of basin
• Runs perpendicular to strike of major fault trends
PS-AAPG Cross-Section CS-3R
PS-AAPG Cross-Section CS-3R
• T.D. 21,215’
• Bottoms out in basal Repettounit
• Cross-section runs perpendicular to strike of many major faults
• Selected for preliminary 1D basin model
American Petrofina Central Corehole #1
1D Basin Model: Boundary Conditions
• Estimated using benthic foraminifera assemblages
• Estimated using mean surface temp (Wygrala, 1989) and paleo water depth
• Subduction through early Paleogene associated with lower heat flow
• High heat flow (~65W/m2) became significant at ~20Ma (Wright, 1991)
Paleo Water Depth
Dep
th (
m)
Hea
t Fl
ow
(W
/m2)
Tem
per
atu
re (
C)
Sediment-Water Interface Temperature (C)
Heat Flow
Time (Ma)
Time (Ma)
10.0
10.0
5.0
5.0
0
0
050
Time (Ma)100150200
0
0
0
2000
3000
4000
1000
10
20
60
40
40
20
30
80
-Spreading center
-Subduction Zone
-Fault
Explanation
(Modified from Dickinson, 1981; USGS)
• Low heat flow during subduction (estimated at 30 W/m2)
• Higher heat flow during Miocene-recent with initiation of strike-slip faulting (estimated at 65 W/m2)
1D Basin Model: Heat Flow
1D Basin Model: Preliminary Results
Temperature (C) Vitrinite Reflectance (%Ro)
Dep
th (
m)
1D Basin Model: Preliminary Results
Time (Ma)
Dep
th b
elo
w S
edim
ent
Surf
ace
(m)
1D Basin Model: Preliminary Results
Time (Ma)
Dep
th b
elo
w S
edim
ent
Surf
ace
(m)
Future Plans
• Refine current 1D model with additional calibration data and supplement with further 1D models in areas of interest
• Generate 2D Basin Model along CS-3R cross-section of LA Basin
• Supplement with additional 1D models where necessary
Thank You!