Earthquake Focal
Mechanisms
Open database file with
Geology options popup menu,
"Earthquake focal mechanisms" choice.
Actions with focal mechanisms
- Plot on map,
Earthquake focal mechanisms.
Plot with symbols colored by fault type, or the beach balls.
- Each type of earthquake with colors
denoting the type of focal mechanism. Get a legend with
Plot, Legend menu choice.
- A beach ball for each focal mechanism. This may be too
cluttered for a small scale map, or one with a large number of
earthquakes. Options to plot on
the map.
- Export beach balls to KML.
- Plot a single focal mechanism by double
clicking an entry in the data table, and picking
Earthquake focal mechanism from the popup menu.
- Stats,
Earthquake Focal mechanisms.
- Options to plot
Multiple Faults on stereo nets,
can help show groupings of earthquakes with similar
focal planes (and hence fault planes). This can be a better option than
trying to make a long table.
- Plot all mechanisms shown in the table
with the Stats button on the database table, and
picking from the popup menu. You should not do
this unless the number of records displayed is
reasonable, after Filtering the
database. This will give you a page with just the focal
mechanisms.
- Create a table by Hiding
fields you do not want to see, and dragging the remaining fields into a good order.
Geology options
and pick
Focal plane analysis.
This allows you to identify ridges as potential fault scarps. You are
looking for ridges parallel to the strike of the faults. While you would
love to match the dips, this might not be possible or might be harder.
Focal mechanism theory
Fault types and focal
mechanisms
Global CMT catalog (earthquake centroids)
Last revision 11/20/2016