The geology, compiled by Th. H. F. Klompe in 1954 from published and unpublished maps of the Direktorat Geologi, has been brought up to date on the basis of investigations carried out to 1962 (Ref. Sigit, Soetarjo, "I. A brief outline of the geology of the Indonesian Archipelago, and II. Geological map of Indonesia;" Direktorat Geologi publication, 1962.)
Base compiled by Th. H. F. Klompe and printed on a Mercator projection.
Geographic names are as of 1962 and in general follows the system of United States Board on Geographic Names.