Volcanological map of Nyiragongo and Nyamulagira volcanoes with the digital seismic network sourrounding the volcanoes. The northwestern side of the volcanoes cannot be covered because of (i) a highly forested area and (ii) the presence of armed local militias bringing strong insecurity in the whole area.
View of the inside crater in 1995, showing on the crater floor the presence of a thick solified crust of the old lava lake. On January 2002, before the eruption, the situation was substantially unchanged.
On January 21st, the central part of the crater was showing an intense fumarolic activity from circural fractures.
The situation, radically changes the day after.