• R1
• R2
• R3
• R4
• R5

• Ra
• Raga Conglomerate
• Raga Formation
• Raichodai Gravel Bed
• Raichodai Pyroclastic Fall Deposit
• Raidenyama Formation
• Raidenyama Unit, Hokkaido
• Raidenyama Unit, Tokyo
• Rakkodake Body
• Raku Andesite
• Ranpi Member
• Ranzan Complex
• Raunenai Formation

• Rb

• Rc

• Rebun Group
• Rebun-Kabato Belt
• Recent Sand Dune, Tottori Sand Dunes
• Red Pumice Tephra
• Refureppu Sandstone Member
• Reiho Tephra
• Reisenji Volcanics Member
• Rekifune Volcanic Rocks
• Rendaiji Conglomerate Member
• Rendaino Terrace Deposit
• Renge Belt
• Renge-dake Granodiorite
• Rengeji Formation
• Rengeji Fossil Forest Member
• Rengeji Granodiorite
• Renge Metamorphic Rocks
• Renkoji Formation
• Renkoji Interbedded Formation
• Rentaki Formation

• Rhyodacitic lapilli tuff
• Rhyodacitic welded tuff
• Rhyolite lava
• Rhyolitic lapilli tuff
• Rhyolitic tuff

• Rifu Formation
• Rifu Granitic Rocks
• Rikuchu Group
• Rikuzenotsuka Formation
• Rinsenji Formation
• Rishiri volcano
• River Terrace Deposits, Hidagawa river

• Rl

• Rm

• Rodai Formation
• Rokkakuzawa Tuff
• Rokkoku Tephra
• Rokugo Formation
• Rokumaebashi Formation
• Rokumantai Formation
• Rokutozawa Formation
• Rokuyaon Gravel Bed
• Ronden mass
• Ronji Formation
• Ronji Mudstone Member
• Roppoishi Lavas
• Roppongi Formation
• Rosse Formation
• Rotary Tephra

• RP

• Rt

• Ru
• Rubeshibe Pyroclastic Flow Deposit
• Rurikei Formation

• RW

• Ry
• Ryodenji Formation
• Ryodenji Member
• Ryokami Formation
• Ryokami Unit
• Ryokamiyama Chert Unit
• Ryoke Belt
• Ryoke Granitoids, Older
• Ryoke Granitoids, Younger
• Ryoke Metamorphic Belt
• Ryoke Metamorphic Complex
• Ryoke Metamorphic Rocks
• Ryori Formation
• Ryoseki Group
• Ryoshudani Member
• Ryoshudani Tephra
• Ryotsu-oki Group
• Ryozen Body
• Ryozen Formation, Fukushima pref.
• Ryozen Formation, Oita pref.
• Ryozen Granodiorite
• Ryozensan Formation
• Ryozen Volcanic Rocks
• Ryubasan Andesites
• Ryugaike Tephra
• Ryugaike Tephra
• Ryugamine Lavas
• Ryugamine volcanic body, Nagano pref.
• Ryugamine Volcanic Rocks, Gifu pref.
• Ryugamizu Andesite
• Ryugashima Dacite
• Ryuge Sands and Gravels Member
• Ryuhozan Metamorphic Rocks
• Ryujin Formation
• Ryukawa Formation
• Ryukoma Granite
• Ryukoma intrusion
• Ryukyu Group
• Ryumon Formation
• Ryuo Lava
• Ryuo Volcanic Rocks
• Ryusekisan Formation
• Ryusenji Formation, Aichi pref.
• Ryusenji Formation, Gifu pref.
• Ryusenzan Group
• Ryuso Group
• Ryuso Sheet
• Ryuso Volcanic Rocks
• Ryusozan Formation