The Strongest Earthquake to Hit Colorado: Strongest Denver, CO Earthquake

#1 Fort Collins (about 66 miles north of Denver)- 6.5 magnitude August 9, 1967

The Closest Faults to Denver Colorado: 

#1 Graben Fault: Near Golden

#2 Golden Fault: Near Golden and to the North Boulder

#3 Rampart Range Fault: North of Colorado Springs

#4 Ute Pass Fault: Near Ute, Woodland Park, Manitou, Pikes Peak

According to the Colorado Division of Energy Management "Geologic studies indicate there are 100 potentially active faults in Colorado and 400+ earthquake tremors of magnitude 2.5 to 6.5 (most are magnitude 3.5 and below) have occurred in Colorado in 140 years".

The Sangre de Cristo Fault, which lies at the base of the Sangre de Cristo Mountains (near Great Sand Dunes National Park) along the eastern edge of the San Luis Valley, (near Alamosa) and the Sawatch Fault, which runs along the eastern margin of the Sawatch Range (near Buena Vista), are two of the most prominent potentially active faults in Colorado.

Not all of Colorado’s potentially active faults are in the mountains and some can not be seen at the earth’s surface. For example, the Cheraw Fault, which is in the Great Plains in southeast Colorado (near La Junta), appears to have had movement during the recent geologic past (possibly 200,000 years ago).

The Strongest Earthquakes in the World

#1 Great Chilean Earthquake - 9.5 magnitude May 22, 1960

#2. Indian Ocean Earthquake - 9.3 magnitude December 26, 2004

#3. Great Alaskan Earthquake - 9.2 magnitude March 27, 1964.

Most Recent Significant Earthquakes:

Magnitude 8.8 OFFSHORE MAULE, CHILE February 27, 2010

Magnitude 7.0 RYUKYU ISLANDS, JAPAN February 26, 2010

Magnitude 6.9 CHINA-RUSSIA-NORTH KOREA BORDER REGION February 18, 2010

Magnitude 5.9 OFFSHORE NORTHERN CALIFORNIA February 04, 2010

Magnitude 7.0 HAITI REGION January 12, 2010

What to do is an Earthquake Strikes:

Earthquakes come without any warning signs that you or I could tell before hand.

If outdoors: Be aware of hazards around you at the time you first feel the tremors start.  If outside Look up first and then head for open ground.

If indoors: Get under a heavy sturdy piece of furniture.  Don't try to leave a building because this could fall on you as you try to leave.

If Driving: Try to steer safely in the open away from tall buildings, power lines, street lights. Stop the vehicle and stay inside.  Once the shaking is over do not drive over bridges, overpasses or near tall buildings.