Microfossils, such as diatoms, incorporated into coastal stratigraphy provide some of the most detailed reconstructions of the history of earthquakes and tsunamis. The application of diatoms to earthquake and tsunami studies is the bread and butter of our lab group. Our group has reviewed thebroader application of microfossils to earthquake, tsunami, and storm studies, the more specificapplication of diatoms to such studies, and an even deeper dive into the application of diatoms to tsunami studies.
Diatoms are photosynthetic, unicellular algae that inhabit freshwater, brackish, and marine environments. Diatoms are a valuable tool in reconstructing paleoenvironmental changes, such as those that occur on subduction zone coastlines during earthquakes and/or tsunami inundation, because of their sensitivity to environmental factors including salinity, tidal exposure, substrate, vegetation, pH, nutrient supply, and temperature found in specific coastal wetland environments. Over time, diatoms become incorporated in coastal sediments, resulting in buried assemblages that represent the environmental changes that have occurred due to earthquakes and tsunamis over thousands of year timescales.
Ongoing work includes developing taxonomic and photographic databases to aid in the identification of diatoms found in the coastal environments along the Cascadia subduction zone.