Mass wasting triggered by the 5 March 1987 Ecuador earthquakes

Engineering Geology
By: , and 



On 5 March 1987, two earthquakes (Ms=6.1 and Ms=6.9) occurred about 25 km north of Reventador Volcano, along the eastern slopes of the Andes Mountains in northeastern Ecuador. Although the shaking damaged structures in towns and villages near the epicentral area, the economic and social losses directly due to earthquake shaking were small compared to the effects of catastrophic earthquake-triggered mass wasting and flooding. About 600 mm of rain fell in the region in the month preceding the earthquakes; thus, the surficial soils had high moisture contents. Slope failures commonly started as thin slides, which rapidly turned into fluid debris avalanches and debris flows. The surficial soils and thick vegetation covering them flowed down the slopes into minor tributaries and then were carried into major rivers. Rock and earth slides, debris avalanches, debris and mud flows, and resulting floods destroyed about 40 km of the Trans-Ecuadorian oil pipeline and the only highway from Quito to Ecuador's northeastern rain forests and oil fields. Estimates of total volume of earthquake-induced mass wastage ranged from 75-110 million m3. Economic losses were about US$ 1 billion. Nearly all of the approximately 1000 deaths from the earthquakes were a consequence of mass wasting and/ or flooding.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Mass wasting triggered by the 5 March 1987 Ecuador earthquakes
Series title Engineering Geology
DOI 10.1016/0013-7952(95)00024-0
Volume 42
Issue 1
Year Published 1996
Language English
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title Engineering Geology
First page 1
Last page 23