DURATION AND EXTENT


Eyewitnesses timed the event using their wristwatches and gave varying accounts of between 1 1/2 and 7 minutes long. Most of the timings ranged from 3 to 4 minutes. The Great San Francisco earthquake of 1906 is said to have lasted only 1 minute.

Different factors can influence the shock variations from place to place. Seismic waves, generated by friction and crushing of rock as they slide past each other, travel outward like ripples on a pond. The amplitude and character of seismic waves are different for different mediums. Unconsolidated fills at Valdez will react quite differently than the bedrock in Chugach Mountains. In certain conditions the intensity of the ground motion may be amplified by the size of the building or, if other events have been triggered.

Seismic Waves

Photo courtesy of

http://www.geo.mtu.edu/UPSeis/waves.html

At any rate, even the shortest estimates of duration had remarkable effects on both man-made and earth-made structures. The main shock was reportedly felt as far away as 600 - 800 miles from the epicenter. The quake was recorded by seismographs around the world.

Table of Contents

Main

Abstract

Introduction

Time and Magnitude

Epicenter

Duration and Extent

Aftershocks

Deformation

Liquefaction

Tsunamis
References