The seismic events that preceded the leaks in the Nordstream natural gas pipelines in the Baltic Sea have been interpreted as explosions on the seabed. We use a polarization-based location method initially developed for marsquakes to locate the source region without the need for a subsurface velocity model. We show that the 2 largest seismic events can be unambiguously attributed to the methane plumes observed on the sea surface. The two largest events can be located with this method, using 4 and 5 stations located around the source, with the uncertainties in elliptical bounds of 30 x 30 km and 10 x 60 km, respectively. We can further show that both events emitted seismic energy for at least ten minutes after the initial explosion, indicative of resonances in the water column or the depressurizing pipeline.
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