Marcellus natural gas trend Experts believe that these were induced seismicity triggered by disposal of wastewater from Marcellus gas wells into Class II underground injection wells. The Ohio Department of Natural Resources Ohio Seismic Network (OhioSeis) determined that the 2011 earthquakes are distinct from previous seismic activity in the region because of their proximity to the Northstar 1, a Class II deep injection well. All of the earthquakes were clustered less than a mile around the well. ODNR then ordered the company to shut down operations and plug the well. ODNR has continued to report increased seismic activity through 2017 in eastern Ohio in
Seismic microzonation characteristics on the ground surface. Regional geology can have a large effect on the characteristics of ground motion. The site response of the ground motion may vary in different locations of the city according to the local geology. A seismic zonation map for a whole country may, therefore, be inadequate for detailed seismic hazard assessment of the cities. This necessitates the development of microzonation maps for big cities for detailed seismic hazard analysis. Microzonation maps can serve as a basis for evaluating site-specific risk analysis, which is essential for critical structures like nuclear power plants, subways, bridges, elevated highways, sky