Earthquake-Induced Liquefaction Near Lake Amatitlan, Guatemala

One of the effects of the February 4, 1976, Guatemala earthquake was the extensive liquefaction which occurred at the settlement of La Playa on the northeast shore of Lake Amatitlan. Ground accelerations in the area resulting from the magnitude 7.5 earthquake are estimated to be of the order of 0.12 g to 0.15 g. The characteristics of the sand are investigated, including its standard penetration resistance and its cyclic loading characteristics. Despite the fact that the sand is somewhat lighter in weight than sand deposits which have liquefied in other earthquakes, its liquefaction characteristics are apparently influenced by the same factors as other sand deposits; its overall behavior is consistent with that exhibited by other sands. The high degree of liquefaction at the La Playa site was probably due in large measure to the lightweight nature of the pumiceous sands.