Abstract
<jats:p>The Kefalonia Transform Fault (KTF) hosts repeated M&gt;6 ruptures with a recurrence interval of 10--20 years, yet its interseismic microseismicity---critical for hazard assessment---remains poorly resolved by sparse land-based networks. This study utilizes a two-month Distributed Acoustic Sensing (DAS) dataset acquired on the seafloor near the KTF in 2024. We applied a matched-filter method, using only five template events, to scan the continuous data. We detected 17,325 microearthquakes, nearly 20 times the 893 events in the concurrent regional catalog produced by land-based monitoring. The newly detected events follow a Gutenberg-Richter distribution within each template family. This newly revealed seismicity manifests as intense, episodic swarms, with one cluster accounting for over 72% of all detections. Our work lowers the local magnitude of completeness by approximately 2 units near the template clusters, indicating that the KTF releases strain near-continuously during its interseismic period through persistent episodic swarm-like activity.</jats:p>