If it were possible to place seismometers and seismic vibrators anywhere below the ground in, for example, an induced-earthquake-sensitive area, we could measure the source mechanism of actual earthquakes, monitor the geomechanical state of the area over time, and quantify the ground motion caused by possible future earthquakes. Moreover, we could monitor fluid flow in aquifers, geothermal reservoirs or CO2 storage reservoirs, with unprecedented resolution. Unfortunately, placing seismic instruments anywhere below the ground is not practically feasible. In this project novel methodology is developed for creating virtual seismic sources (earthquakes or seismic vibrators) and virtual seismometers anywhere in the subsurface, from seismic measurements (active and passive) at the earth’s surface. This is called Virtual Seismology (VS). VS accurately mimics the responses to actual earthquakes that would be recorded by actual buried seismometers, including all multiple scattering effects.