Development of a web based 3d visualization and analytics platform for post-earthquake assessment

Earthquakes are one of the frequently encountered natural hazards. The natural hazards may cause losses of lives, properties, and sometimes both. A thorough investigation of different forms of geoinformation is needed to understand the occurrence conditions and the risks associated with seismic hazards. With the availability of multi-platform and high-resolution geospatial datasets, vast amount of geodata can be obtained and evaluated in order to analyze land surface information before and after an earthquake event promptly; and to help the first responses and emergency management agencies with the mitigation efforts. An earthquake with Mw 6.8 occurred on January 24, 2020, in Elazig, Turkey; and 41 people were killed, and buildings and infrastructure were damaged. Even though geomatic professionals were able to gather and process various geo datasets, their accessibility and usability were still limited due to the requirement of advanced visualization, processing, and analysis tools by other participants, such as geoscientists, local authorities, and residents. Therefore, it was aimed in this study to design and implement a web-based framework called EQ4D that offers various functionality to the users for the multi-sensor and multi-platform 4D data. The platform presents several geoanalytic methods, including change detection, 3D surface measurements, etc. The 3D visualization of geospatial datasets in EQ4D was implemented using the Cesium JS and Potree libraries. For storing and handling measurement data and spatial queries PostGRE/PostGIS spatial database management system was used. The EQ4D accommodates efficient visualization and analysis of geodata by geoscientists and is customizable for other natural hazards and for the use of non-professionals such as citizen scientists.