Extended Data Fig. 1: Map of the Baltic Sea region with coring sites.
From: Methane leakage through the sulfate–methane transition zone of the Baltic seabed
a) Details of the framed areas are shown in subsequent figures as numbered: Extended data figure (EDF) 3 covers Arkona Basin, Extended Data Fig. 4 covers Bornholm Basin, Extended Data Fig. 5 covers Bothnian Sea, and Extended Data Fig. 6 covers Bothnian Bay. Brown areas represent organic-rich, Holocene mud (Geological Survey of Denmark and Greenland). b) Detail of coring sites in the Gotland Basin showing coring locations across two transects with details shown in Fig. 1 and Extended Data Fig. 2. The bathymetry basemap was acquired from HELCOM (https://helcom.fi/baltic-sea-trends/data-maps/) and is used also in subsequent figures. Credit: basemap, ESRI, GEBCO, NOAA, National Geographic, Garmin, HERE, Geonames.org, and other contributors.
