山丘 (行星地質) 山丘 pl tholi是在行星地質學用來描述一個小小的圓頂的山或小山這個詞是從希臘文θόλος 轉過來的原本的意思是有著圓錐形或拱形屋頂的建築物羅馬人翻譯這個字成為拉丁文的tholus意思是圓頂 cupola 或 窟窿 dome 在年代早期國際天文學聯合會 IAU 將tholus作為官方描述火星和其他行星與衛星地形特徵的術語使用中性的拉丁文或羅馬字描述的理由是在其地質或地貌被測量或確認之前就可以為它命名 例如許多山丘似乎是源自火山而這個名詞並未意味著特定的地質成因目前IAU確認了個術語 參見行星命名山丘使用在金星火星和木星的衛星艾歐 Map of the Tharsis quadrangle showing major features several of which are tholi Tharsis contains many volcanoes including Olympus Mons the tallest known volcano in the solar system Lower volcano is Ceraunius Tholus and upper volcano is Uranius Tholus as seen by Mars Global Surveyor Mars Orbiter Camera Ceraunius Tholus is about as high as Earths Mount Everest Western part of Jovis Tholus as seen by THEMIS on Mars Odyssey spacecraft Jovis Tholus is in the Tharsis quadrangle