I use seismology to answer fundamental questions about ice-covered environments. I am very interested in the changes occurring at the edges of Earth's polar ice sheets, including iceberg calving in Greenland and fracture within the Antarctic's ice shelves. I also apply my understanding of ice dynamics and seismic-wave generation on Earth to investigate the surfaces and interiors of distant ice-covered moons within our Solar System.

My work on glacial earthquakes has received multiple press write-ups:
A recent Science Highlight on IRIS
An article in EOS
An EOS Editors' highlight

My current postdoctoral research focuses on testing hypotheses for the formation of surface features on the icy moons Europa (of Jupiter) and Enceladus (of Saturn). I am pursuing this work through geophysical study of rifts within the Ross Ice Shelf in Antarctica, using seismic events generated within the ice to constrain the stress state surrounding those rifts. Europa and Enceladus both have heavily fractured icy surfaces, and it is thought that tidal stresses drive this deformation. Beneath their icy shells, both moons are thought to have oceans of liquid water, and these environments may host life. We have no direct observations from the surface of either moon, which make analog studies on Antarctic ice shelves extremely valuable. Seismic data is uniquely well suited to answer questions about both deformation on the surface and on the structure within these moons (like ice-shell thickness), and future missions to land seismometers on icy moons are in the planning stages at NASA. My analog work in this field also helps us prepare to collect seismic data directly on these icy worlds.

My PhD research centered on investigating Greenland's largest glaciers and how they are changing. Iceberg calving at marine-terminating glaciers accounts for up to half of the net ice lost from the Greenland ice sheet annually, yet many glaciers around Greenland are extremely remote and few of the largest calving events at these glaciers have ever been observed. I used seismic data to investigate buoyancy-driven calving and glacier evolution by studying glacial earthquakes. These are seismic events up to magnitude ~5 that are generated when icebergs up to a cubic kilometer in volume calve from marine-terminating glaciers. Through analysis of these events we can constrain the grounded state of a glacier, identify the type of calving event, and track multiple-iceberg calving sequences across an individual glacier terminus. In recent work I demonstrate that the masses of iceberg that generate glacial earthquakes span three orders of magnitude, reaching sizes much smaller than previously recognized. These results suggest that buoyancy-driven calving is the primary driver of dynamic mass loss at Greenland's largest tidewater glaciers during the calving season (Olsen & Nettles, 2019). I have also developed new models to describe the glacial-earthquake source, and these models improve estimation of the magnitude of glacial earthquakes. I continue to work to understand the relationship between the iceberg that calves and the size of the glacial earthquake it generates.