BackgroundGunung Raja (or Raya) appears to be a remnant stratovolcano with a large caldera open towards the entire SE side that may originally have been about 3 km in diameter. The Bukit Sabanda cone lies about 2 km NE of the caldera. Although eroded, the volcanic features are still evident. Mapping related to geothermal exploration of the adjacent Kunyit volcano identified a "Raja volcanic unit" as Middle Pleistocene, but did not include this volcano in the mapped area that was published (Silitonga et al., 2015).
Source: Smithsonian / GVP volcano information
See also: Sentinel hub | Landsat 8 | NASA FIRMS