Submarine Volcanoes Polygons (100k)

Submarine volcanic structures and eruption centers including hydrothermal activity, mapped by various national and regional mapping projects and recovered in the literature. Locally polygons are extended on land to include the emerged portions of the volcanoes. Polygons represent areas larger than 4 hectares. (for smaller areas, see volcanoes points layer) Note: blank areas do not necessarily correspond to no occurrence.