FEATURE OF THE 3 MARCH 1985 CHILE EARTHQUAKE - POSSIBLE TERRAIN AMPLIFICATION.

This paper presents results of site-response experiments performed five months after the M//s equals 7. 8 Central Chile Earthquake of 3 March 1985. The objectives of the experiments performed are to identify amplification due to topography and geology. Topographical amplification at Canal Beagle, a subdivision of Vina del Mar, was hypothesized immediately after the main event, when extensive damage was observed on the ridges of Canal Beagle. Spectral ratios determined from aftershock data obtained from a temporary dense array are used to show that there was substantial amplification of motions at the ridges of Canal Beagle.