Association of volcanoes with plate boundaries. (Source: USGS)
USGS image, public domain. https://pubs.usgs.gov/gip/dynamic/Vigil.html
Artist’s cross section illustrating the main types of plate boundaries (see text); East African Rift Zone is a good example of a continental rift zone. (Cross section by José F. Vigil from This Dynamic Planet — a wall map produced jointly by the U.S. Geological Survey, the Smithsonian Institution, and the U.S. Naval Research Laboratory.)