Review of Seismology Concepts
Faulting

Basic Types

Surface Faulting

  • Strike-slip
  • Dip-slip
    - Normal
    - Reverse
  • Combinations

Mid-Plate Events

No apparent fault rupture due to depth or cover by alluvial deposits

Subduction Zones

Common in Japan, Mexico, Puget Sound, Alaska, South America

 

Rupture Length and Offset

These can be signficant, as shown below.

Event
Length
Offset
1906 San Francisco
250 miles
21 feet
1960 Chile
600 miles
--
1971 San Fernando
15 miles
3 feet
1857 Fort Tejon
--
49 feet

 

Terminology

Plan View

View along Section E-E

OA - Epicentral distance
OB - Hypocentral distance
OC - Distance to surface trace
OD - Distance to rupture