DEEP TIME THROUGH THE SENSES: SONIFICATION OF THE GEOLOGIC TIME SCALE

Geologic time is a major organizing idea in science. Since it's impossible through direct experience in the natural world to perceive changes over millions of years, scientists reason about the earth's past from rocks and through representational tools such as time scales and metaphors. For many people, however, deep time is a critical barrier to learning science; the meaning of immense spans of time is elusive and unfamiliar. This paper reports on some exploratory educational research involving the sonification of the geologic time scale. Sonification is the process of systematically transforming into dimensions of sound scientific data, such as delineated lengths of geologic time, for purposes of making hidden patterns audible. We based design decisions on important findings in music cognition, cross-modal, spatial, and temporal perception, and research on emotion and meaning through music. The sounds were organized according to four main principles that we think form the basic structure of deep time: the immensity principle, the people principle, the linearity principle, and the kinds of change principle. Pitch, loudness, timbre, note length, and note density were systematically varied to induce meaning around space and time according to these four principles. While listening for the structure of the time scale, students simultaneously watch a graphical interpretation of the sounds on a computer screen to support cross modal spatial reasoning. Supplemented with meaningful imagery and information about earth's rich history, this six-minute geologic time scale sonification could serve as an interactive clinical interview tool to probe students' knowledge of pivotal geoevents spanning 4,560 million years of earth history. By helping listeners construct the underlying structure of geologic time through a multi-sensory listening experience of time and space, this inherently sensory, spatial, and temporal tool might reduce the novelty of deep time.