Cool! Here's an image [1] of an earthquake recorded on another DAS tap from an article [2] linked to in the extensive description on the livestream.

  Fig. 2. This sample data plot shows ground deformation along the fiber-optic cable deployed at Grímsvötn over about 50 seconds. A large event arrived near the middle of the cable at about 18:44:50 on this day as it propagated through the glacier. The signal observed around kilometers 10–12 of the fiber, which sat on top of the subglacial lake, oscillated with longer periods than the large event and may have been caused by bending of the ice sheet on top of the lake.

[1]: https://i0.wp.com/eos.org/wp-content/uploads/2021/12/ground-...

[2]: https://eos.org/science-updates/sensing-icelands-most-active...