PUEBLO-FT. REYNOLDS
Earthquake ID:  1 Date: 12/04/1870
Intensity:  VI
Time: 12:00 PM
Magnitude:  
Earthquake Depth:   (kM)
Magnitude USGS:  
Latitude: 38.5
Magnitude Other:   Longitude: -104
 
Earthquake Information:
The first earthquake of record to center in Colorado occurred on December 4, 1870. The most complete description of this event is contained in the Pueblo Chieftain on December 8, 1870. Included in this issue are the reactions of various community members to the earthquake and reference is made to a letter from Fort Reynolds that states “Bottles on my washstand standing about one inch apart were violently knocked together. The shock was accompanied by a rumbling noise and appeared to move from east to west. It was also felt on the opposite side of the [Arkansas] river.” Maximum intensity for this event was VI (Hadsell, 1968). According to the Colorado Transcript on December 7, 1870 the earthquake was felt by a least two citizens in Golden. Other references to this earthquake are found in the Rocky Mountain News (12/10/1870) and the Central City Register (12/11/1870). Hadsell (1968) suggested the earthquake was felt over about 160,000 km 2 .
 
References:
35 - Docekal, J., 1970, Earthquakes of the stable interior, with emphasis on the midcontinent: University of Nebraska, Ph.D. Dissertation, 332 p.
45 - Hadsel, F.A., 1968, History of earthquake activity in Colorado, in Hollister, J.C., and Weimer, R.J., eds., Geophysical and geological studies of the relationship between the Denver earthquakes and the Rocky Mountain Arsenal well: Colorado School of Mines Quarterly, v. 63, no. 1, p. 57-72.
90 - Rizzari, F.B., 1951, It CAN’ T happen here: A brief history of earthquakes in Colorado: The Denver Westerner’s Monthly Roundup, v. 15, no. 12, p. 5-15.