Development of Seismic Intensity Maps Using Low-Cost Micro-Electro-Mechanical Systems Seismic Network

The low-cost IoT seismometer (LCIS), which embeds a micro-electro-mechanical systems accelerometer and LTE communication sensor, has been developed and deployed in South Korea. Currently, approximately 7,000 stations (with an average density of 0.07/km2) with LCIS devices are operating in real-time, which is about 25 times higher density than the national seismic network with high performance seismometers. This study shows a method for processing LCIS data and plotting an intensity map considering its installation characteristics and density. The majority of LCISs are installed inside buildings, so an adjustment converting to the free-surface equivalent vibration is applied. Seismic intensity maps are derived using only high-density LCIS network data, which showed very similar distributions to the maps from the high-performance seismometer network. This validates the usefulness of the LCIS, a low-cost but new technology on seismic network devices, for the generation of high-resolution seismic intensity map and earthquake early warning systems.