1. Continental shelf offshore San Pedro/Long Beach showing general location of the Wilmington Graben in red
Small circles are earthquake epicenters
Line of cross section for seismic Line 84 across Beta oil field southern portion of Wilmington Graben

2. Seismic cross section for Line 84 showing sedimentation southwest and northeast of the Palos Verdes fault through Beta oil field.

3. Typical log for the Beta oil field
Depth (ft)
2000
4000
Typical log for the Beta oil field
Production from zones A through F in the upper Miocene Delmontian
6000

4. Location of Beta 3D seismic survey data used by geophysical consultant Mark Legg of Legg Geophysical to evaluate the structure of Wilmington Graben

5. Stratigraphy of the San Pedro shelf
Beta field production from Delmontian (Monterey Formation)
Black areas represent missing section at unconformities

6. Time-slice from 3-D seismic volume at 1688 ms two-way-travel-time, at about the Mohnian/Delmontian boundary.
Major structural features are identified including small domes that may form closures for structural traps.
Fault picks are shown by X’s; stratigraphic horizon picks by small colored dots.
Grid shows California State Plane Coordinate System, Zone VI, NAD27 with labels in feet.

7. Structure contour map of basement in the Wilmington Graben based on Beta 3D seismic survey
Areas uplifted by two large basement blocks (light blues to oranges) in the northwest and southeast of the studied area
Average depth to basement 10,000 ft
Lines of seismic cross sections for lines 41, 181 and 556 shown

8. Structure contour map of the top Mohnian based on Beta 3D seismic survey
Miocene and Pliocene sediments are folded into anticlines above basement peaks\
Average depth to Mohnian approximately 5600 ft
Lines of seismic cross sections for lines 41, 181 and 556 shown

9. Seismic cross section for Line 556, northwest to southeast along the Wilmington Graben
Basement in purple
Mohnian –Delmontian boundary in blue

10. Seismic cross section for Line 181, southwest to northeast across southern end of Wilmington Graben

11. Seismic cross section for Line 41, southwest to northeast across northern end of Wilmington Graben
Uplifted basement block to NE end of line

12. Potential CO2 Sequestration Targets for the Wilmington Graben Based on Legg, 2007