Earthquakes

2 Pages 457 Words

Earthquakes

The Mapleton, Utah area is near an active fault. This fault’s name is the Wasatch Fault. The Wasatch Fault actually runs right through the center of Mapleton. According to the Utah Geological Survey map showing earthquake faults (which I have enclosed in my portfolio), my family’s house is located less than a mile away from the fault. This was a scary thought to me that I live so close to a fault and even more of a scary thought that the fault is an active fault.
The Wasatch Fault’s most recent earthquake-at the time I wrote this report-was Feb 16, 2005 at 8:03 am (2). Although this quake was very small and close to invisible in magnitude, it still shows that the fault is indeed active. This particular quake had a magnitude of 1.4. An earthquake this small does not tend to create any immediate harm or fear since they usually go unfelt, but that doesn’t mean the chances of having a big dangerous quake is out of the question. Many little earthquakes have occurred along this fault. One would be a .5 magnitude quake on Feb 13, 2005, and another Feb 11, 2005 with a magnitude of 1.1 (2). Because the fault has not had any major earthquakes recently does not mean it is safe and cannot happen.
The recurrence interval for the Wasatch Fault is displayed below (3);
Recurrence Intervals for the Wasatch Front Region
Magnitude Range Estimate of Recurrence Interval Time Since Last Earthquake
Greater than 3.0 4 months 10 months
Greater than 4.0 18 months 28 months
Greater than 5.0 8.7 years 11.8 years
Greater than 6.0 48 years 25 years
Greater than 6.5 120 years 66 years
Between 3.5 and 4.5 11 months 10 months
Between 4.5 and 5.5 4.6 years 11.8 years
Between 5.5 and 6.5 24 years 25 years

My house is built on loose, water-saturated, sandy soil. This geologic material has very moderate potential for liquefaction. Same goes for our Elementary School in Mapleton. WE don’t have a hospital in Mapleton, we have to ...