Felt reports
Sketchy news from the region indicates that all four tremors were sharply felt in the Trinidad area but there have been no reports of damage or injuries (and none would be expected for quakes of this magnitude). People reported windows jiggling, dishes rattling and light fixtures shaking. There were reports of some light items toppling from tables or shelves and a few pictures fell from walls.

The M3.7 aftershock was felt at the Primero School by student and staff.

The radius for felt reports is on the order of 15 -20 miles.

According to Mr. Thompson, who has lived in Cokedale for 85 of his 90 years, the quakes of September 4 passed without him noticing them, but the M4.5 on September 5 shook strong enough to jar him from sleep. He said it was a mild tremor, shaking the pictures on walls and jiggling the windows, although it was still quite minor yet the strongest he had felt since moving to Cokedale when he was 5 years old. He was more concerned with the bear problem and that the hot, dry weather has driven them out of the mountains and they are raiding the garbage bins, scattering the trash about. He was not aware of any rock falls on the roads, but he said he doesn't get out much any more.

Mr. Johnson also noted that the quake sounded like thunder and that's probably what really woke him up - not the shaking. "Probably get some more thunder later this afternoon", he said, "as there are some clouds a brewin' to the south".

Special notes
Cokedale and Bon Cabo are old coal mining districts of southern Colorado and there is a strong likelihood that the tremors are related to rock bursts in the underground mines and not of tectonic origin. Mr. Johnson said a number of mines excavated large quantities of coal leaving a catacomb of tunnels and caverns under the mountains.

For more info visit: Cokedale National Historic District.

Additional seismic information links:

• Seismo-Watch Links to Colorado Activity
• NEIC Earthquake Report Page.
  • Historical seismicity of the area
  • Phase (Arrival Time) Data
  • Earthquake History of Colorado
• More information about earthquakes and geology in Colorado
• Colorado Geologic Survey

Seismograms of the earthquake series from nearby stations:

• None at this time

Mainstream media news reports:

• Two more quakes rattle Trinidad area, The Pueblo Chieftain Online - Thursday September 06, 2001
• More quakes rattle Trinidad area, AP via Denver Post, September 5, 2001
• Trinidad quake latest in bunch rocking state, AP via Colorado Springs Gazette, September 5, 2001