Earthquake swarms on the Mid-Atlantic Ridge: assessing the applicability of a global catalogue for seismic analysis

The Mid-Atlantic Ridge is mostly positioned at great distances from on-land seismic stations. As a result, analyses of earthquakes are challenging, with focused studies often coming through temporary local recording devices. Although previous work has explored batches of local earthquakes (known as swarms) to uncover information on plate tectonic boundary kinematics, there has been limited large-scale analysis of swarms across the ridge. Here, we take a global earthquake dataset and apply cluster analysis to produce an overview of swarm dynamics across the Mid-Atlantic Ridge latitudes 52 o N and 63 o N (a portion of Reykjanes Ridge). Our work produces over 150 swarms as compared to only 6 swarms discussed in previous work for the same location and time period. In particular, the swarms generated from this dataset are fleeting in time (<24 h) and stable in location (<20 km). The work here also outlines the limitations of using such a generic global dataset and highlights that this study is unable to fully capture the seismic dynamics of a Mid-Atlantic Ridge earthquake event. However, this methodology of large-scale analysis of a broad dataset can supplement local high-resolution data with quantity of swarm events over quality of seismic characteristics. Here, we provide an overview of timing, location, and occurrence of swarms–identifying potential areas for future exploration.