Yakima Earthquake Case Study

Situation On March 16th 1980, in the usually calm and tranquil southeast region of Washington State located in the Cascade Mountains, began to tremble with earthquake activity lasting until the afternoon of the 26th of March. This was the first of many warnings to geographers and local authorities of the impending dangerous eruption coming from the normally silent Mount Saint Helens. The richter magnitude range was 2.6-4.2. There were 142 recorded earthquakes over 2.4 in the 24 hours between March 26 and 27th. The volcano began to spew ash at 1236. (Girty, P. 2) The ash column reached 829 meters above the peak. The ash spewed intermittently through the 21st of April lasting seconds all the way to nearly an hour. Due to the activity, a new crater in the mountain formed and merged with it's mother. Activity briefly ceased in late April until May 7th. This kept up until May 16th. Nearly 10k earthquakes were recorded for the first half of May 1980. The activity came to a head on Sunday May 18th when the volcano dramatically erupted bright and early at 0832. The explosion was catalyst to a debris avalanche
Cities such as Yakima, Washington recorded over three meters deep of ash fall coverage throughout the city. Yakima was incorporated in 1886. The City is located in the center of the State of Washington, approximately one hundred and forty miles southeast of Seattle, and approximately one hundred and fifty miles east of Mount Saint Helens with a population of about 55,000 in 1980 (Carson, 2000).
The Yakima Valley is commonly referred to as "The Fruit Bowl of the Nation" with major production of fruits such as apples, and wine grapes, and multitude dairy products. The total agricultural production of the Yakima basin is nearly $2 billion annually (Zais,2001). The ash fallout was detrimental to the season’s production and caused a decrease in production and revenue that year