We propose using geomicrobiology to overcome the primary issue in documenting prehistorical coastal hazards which is the faint distinction between storm and tsunami deposited sediments. In 2017, we completed our study in Phra Thong Island, Thailand that shows that microbial community analysis can be used to successfully distinguish between sediment deposits of 2004 Indian Ocean tsunami and a 2007 storm. We aim to publish our Thailand dataset in 2018. We will then analyze another site sampled in 2017 where the 2004 Indian Ocean tsunami deposit is overlain by a known storm deposit near Cuddalore, India. The Indian dataset will further test the robustness of this approach in different settings and allow us to test a new technique for extracting intracellular DNA.