On the Perception of Audified Seismograms

Abstract

ABSTRACT Recordings of the Earth’s oscillations made by seismometers, following earthquakes or other geophysical phenomena, can be made audible by simply accelerating and playing them through an audio reproduction system. We evaluate quantitatively the possibility of using such an acoustic display of seismic data for practical applications. We first present to listeners examples of two categories of data, based on geophysical parameters that are not revealed to them. In the first test, the control parameter is the terrain, either oceanic or continental, sampled by the propagating seismic wave. In the second test, it is the geometry of the seismic fault, which can be either thrust or strike slip. The listeners are asked to associate each of a set of audified seismograms, that are presented to them binaurally, to either one of the two categories. At the end of the test, they are asked to define the features of audified signals that helped them in completing their task. The third and final test consists of repeating the fault‐geometry categorization exercise after a brief training session. About 35, 27, and 17 listeners participate in the first, second, and third tests, respectively. Both sexes, a wide range of ages, and three different backgrounds (acousticians, geoscientists, and physicists) are represented. Although the number of listeners is too small for a definitive statistical analysis, our results suggest that listeners are able, at least in some cases, to categorize signals according to all the geophysical parameters we had chosen. Importantly, we clearly observe that listeners’ performance can be improved by training. Our work opens the way to a number of potentially fruitful applications of auditory display to seismology.