> They would have to transmit accelerometer data (at a reasonably high sampling rate) in real time. Not necessarily. They could also follow the SETI approach b

> They would have to transmit accelerometer data (at a reasonably high sampling rate) in real time. Not necessarily. They could also follow the SETI approach by providing an app for volunteers who collect the data. The app evaluates the data, filters the noise and sends the abstract data results to a server. There are already many data collections of past earthquakes which could be used as patterns for a neural network in the app.