Petra,
Do you remember the musical "Gigi" - I think there was a movie with Maurice
Chevalier too. Anyway, there is a song in that musical in which the man and
his wife recall a night in June (or was it May). The man would remember something
from that night, then the woman would remember it differently. The refrain was
"Ah yes, I remember it well".
The reason for catalogs and record keeping is to help us remember things like
when and where earthquakes occur.
In your post you note:
"..... No other activity of any note happened until the same date as the Turkey quake
on 9/22/99. I'm quite certain it would have been considered a far-field triggered quake as it
happened within hours of the Turkey event."

My memory was not the same, so I checked the catalogs. The event you are
referring to here did happen in the Rohnert Park area (Ml 4.2) on Sept. 22, 1999,
but was not associated with the Turkey earthquake. The earthquake which may
have triggered this event occurred in Taiwan (Mw 7.7 - the Chi-Chi earthquake)
on Sept. 20, 1999.

The reason you may recall an association with the Turkey earthquake was that
a few hours after the Turkey earthquake on August 17, 1999 a Ml 5.0 earthquake
occurred near Bolinas south of Rohnert Park (on August 18).

Anyway, you are correct that both of these could well have been triggered. All
that is required for far-field triggering is that the local ground motion be sufficient
to move a fault closer to rupture or to actually initiate rupture. This is sometimes
quite difficult to tell.

An interesting event (or non-event) that shows how difficult it is to distinguish
a local event from the seismic waves from a teleseismic earthquake is recorded
on the California listing for the day as an earthquake at Hot Creek NV as follows:

3.7 2001/07/07 02:49:09 38.319N 114.959W 15.0 18 km (11 mi) ESE of Hot Creek, NV

Note this is local time, U.T. time is 09:49:09

NEIS gives the following parameters for the Peru earthquake:
2001/07/07 09:38:43.4 17.4S 71.8W Ms7.2 M NEIR NEAR COAST OF PERU
about 10 minutes, 16 seconds earlier.

The P- wave will take around 10 minutes 30 seconds to travel from Peru to
Nevada. Was the event recorded at Hot Creek, NV an early arrival wave from Peru,
a real local event or a triggered event from an early p-wave arrival? Only
close examination of the seismogram will tell for sure. So, the point is a lot
of triggered earthquakes may be missed because they look like arrivals from
large teleseismic earthquakes.

Keep up the good observations, and keep a log as you and Don are doing -
it is the only way to keep memory at bay.

• California - Nevada earthquakes