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List of geological units in Gunma prefecture

A list of stratigraphic units, igneous bodies, and geological structures reported from Gunma prefecture, Kanto region, Honshu island, Japan.

Photographs of geological units in Gunma prefecture

Paleozoic
Kazekuchi Formation
Joetsu Belt
Katashina Belt
Shibutsusan Ultramafic Rocks
Kawaba Ultramafic Rocks-Metagabbros-Schist Complex
Kawaba Metamorphic Rocks
Iwamurotoho Ultramafic Rocks
Carboniferous (358.9-298.9 Ma)
Kawamo formation?
Mugiukoji formation
Carboniferous-Permian
Joetsu Belt
Tanigawadake Belt
Tanigawadake Body, Serpentinite
Permian (298.9-252.17 Ma)
Joetsu Belt
Katashina Belt
Tokura Ophiolite
Tanigawadake mélange
Okura formation
Mukuruma formation
Kuwashiro formation
Kurumigaito formation
Kinshozan Quartz Diorite
Jurassic (201.3-145.0 Ma)
Okutone group
Northern Chichibu Belt
Sumaizuku Unit
Kanozan Limestone
Hebiki Unit
Kamiyoshida Unit
Kamiyoshida Subunit
Manba Subunit
Kashiwagi Unit
Southern Chichibu Belt
Otchizawa Formation
Ashio Belt
Omama Complex
Kurohone-Kiryu Complex
Iwamuro formation
Tokurazawa Formation
Cretaceous (145.0-66.0 Ma)
Atokura Formation
Shimokanoya Mudstone Member
Nakanokaya Conglomerate Member
Miyamuro Sandstone and Mudstone Member
Okuwahara Sandstone Member
Atokura Conglomerate Member
Sori-type Granitic Rocks
Sori Granodiorite
Sanchu Graben
Sanyama Formation
Sebayashi Formation
Ishido Formation
Shirai Formation
Ashio group
Yorii Plutonometamorphic Complex
Yotsumatayama Quartz Diorite
Sudagai Granite
Tadamigawa Granites
Cretaceous-Paleogene
Daigenta Granite
Minakami Quartz Diorite
Cretaceous - Paleocene
Sanbagawa Belt
Mikabu Unit
South Unit
Middle Unit
North Unit
Paleogene
Okunikko rhyolites
Sudagai granite
Paleocene (66.0-56.0 Ma)
Kanayama Welded Tuff (Kanayama rhyolites)
Eocene (56.0-39.0 Ma)
Kottateyama formation
Neogene
Echigozawa Porphyrite
Doai Quartz Diorite
Nishikuro Diorite Porphyry
Keizuruyama Lava
Akagine Rhyolite
Neogene-Pleistocene
Omeshi volcano
Omeshi Lava
Kenashi Lava
Upper Myojin Lava
Lower Myojin Lava
Hafu Lava
Toyooka Lava
Kuresaka Lava
Horaguchi Lava
Tsubakuro Lava
Banki Lava
Takama Lava
Namasu Lava
Yodate Lava
Matsuiwa Lava
Yokoteyama Lava
Hidakayama Lava
Takaishiyama Lava
Iozawa Metasomatic Rocks
Miocene (23.03-5.33 Ma)
Nagaiwa formation
Kanohara formation
Shimonita group (Shimonita formation)
Annaka Group
Itahana Formation
Tate Tuff
Yamaguchi Tuff
Nakazeki Tuff
Masudagawabashi Tuff
Haraichi Formation
Kitamura Tuff
Baba Tuff
Niwaya Formation
Tomioka Group
Haradajino Formation
Obata Formation
Kojakui-sho
Ushibuse Formation
Garameki Formation
Hirosawa Conglomerate
Yabuzuka Formation
Midoricho Formation
Mamioka Tuff
Gokan formation
Akaya formation
Hara formation
Kassezawa formation
Fukiwari welded tuff bed
Motojuku formation
Shirasunayama welded tuff bed
Takadayama formation
Kirigakubo formation
Azuma formation
Daido formation
Tone welded tuff bed
Katashinagawa rhyolites (Katashina rhyolites)
Okkai group (Okkai formation)
Kinugawa rhyolites
Mamioka formation
Ozawa formation
Yoshii formation
Minakami Group
Namezawa formation
Upper Namezawa formation
Lower Namezawa formation
Yubara formation
Awazawa formation
Okura formation
Sarugakyo group
Fukushima formation
Orida formation
Higashizawa formation
Kuryu formation
Iizuka formation
Negoya Formation
Kawarahata Formation, Sawatari Formation
Miocene-Pliocene
Takai Volcanic Rocks
Pliocene (5.33-2.58 Ma)
Yokokabe Formation
Kawarayutoge Formation
Yanba Formation
Kirizumi Volcano
Yunoiri member
Aimagawa Formation
Akima Formation
Upper part
Chausuyama Welded Tuff Member
Otogai Tuff Breccia Member
Nagaiwa Lapilli Tuff Member
Morikuma Volcanic Breccia Member
Kirizumi Formation
Dozen member
Yunosawa member
Usuiko member
Kubo member
Kogura Formation
Myogi formation
Kengamine formation
Sasatoya formation
Nagaone formation
Iwashima formation
Sakaue formation
Kadokai Formation
Kirigakubo formation
Oze lava
Byobuiwa formation
Kawarayu Quartz and Granodiorite Porphyry
Kumori Dacite
Osaka Dacite
Pliocene-Pleistocene
Godo Formation
Pleistocene (2.58- 0.01Ma)
Agatsuma Clay
Imai Gravels
Koneyama Formation
Kennomine formation
Onogami formation
Nenbutsudaira lava
Nakanojo lacustrine formation
Numata lacustrine formation
Tsumagoi formation
Aira-Tn pumice bed (AT)
As-BP Tephra
As-MP Tephra
As-SP Tephra
As-YP Tephra
As-Sj Tephra
Maebashi peat bed
Nakanojo lahar deposit
Omama alluvial fan deposit
Kanto loam formation
Lower loam formation
Middle loam formation
Hassaki pumice bed (HP)
Kanuma pumice bed (KP)
Iwajuku-I formation
Hanamagari formation
Nakanojo lapilli formation (JLP)
Sugao Formation
Ojo Formation
Kanpo volcano
Kanpo Volcanic Rocks
Sugaotoge Andesite and Dacite
Fudosawa Andesite
Shiraiwazawa Andesite
Azumaya volcano
Urakurayama volcanic edifice
Kamitokusa Lavas
Kaminokai Lavas
Akagawa Lavas
Nittazawa Lavas
Akagi Volcano
Younger Stratovolcano
Post-caldera stage
Jizodake Lava
Kono Lava
Pumice-eruption stage
Volcanic Fan 2 Deposit
Garan Pyroclastic Deposit
Nagumo Pumice Flow Deposit
Toshimaru Pumice Flow Deposit
Ogo Pumice Flow Deposit
Wakubara Pumice Flow Deposit
Fujiki Pumice Flow Deposit
Tanashita Pumice Flow Deposit
Fudo Pumice Flow Deposit
Younger volcanic-cone-building stage
Volcanic Fan 1 Deposit
Itoi Pumice Flow Deposit
Kurayamikubo Lavas
Arayama Lava
Kawaguchigawa Lava
Nabewariyama Lava
Funegahara Lava
Masugatayama Lava
Suzugatake Lava
Nashiki Debris Avalanche Deposit
Older Stratovolcano
Rashirashizawa Lava
Riheijaya Lava
Kurobiyama Lava
Nirezawa Lava
Mugikubo Lava
Haruna volcano
Older Haruna Fan Deposits
Miyazawa Pyroclastic Flow Deposit
Older Haruna Volcanic Dykes
Older Haruna Volcanic Products
Haruna Tuff Breccia
Younger Haruna volcano
Hr-HP Tephra
Shirakawa Pyroclastic Flow Deposit
Hassaki Fall Tephra
Harunafuji Lava
Jagatake Lava
Somayama Lava
Mizusawayama Lava
Mizusawayama Pyroclastic Flow Deposit and Talus Deposit
Younger Haruna Volcanic Fan Deposit
Jinba Debris Avalanche Deposit
Asama-Eboshi volcanoes
Stage I
Iwayakan'non stratovolcano
Iwayakan'non Lava
Stage II
Kokuzo Lava
Kanahara Lava
Omuro Lava
Ofuji Lava
Gotomiki Lava
Eboshidake stratovolcano
Upper Eboshidake Lava
Iwashimizu Formation
Narahara Lava
Lower Eboshidake Lava
Stage III
Kakuma-Nabebuta stratovolcano
Kakuma-Nabebuta volcanic products
Yunomaru lava dome
Yunomaru lava
Sajikiyama lava dome
Sajikiyama Lava
Kosajikiyama lava dome
Kosajikiyama Lava
Sanpogamine stratovolcano
Kagonotoyamakita Lava
Sanpogaminenishi Lava
Ikenotaira pyroclastic cone
Takamineyama stratovolcano
Takamineyama Lava
Stage IV
Murakamiyama lava dome
Murakamiyama Lava
Mizunoto stratovolcano
Nishikagonotoyama lava dome
Nishikagonotoyama Lava
Higashikagonotoyama lava dome
Higashikagonotoyama Lava
Kurofu stratovolcano
Zappa stage
Kengamine stage (80 ka)
Mitsuone stage
Sennin stage
Sekisonzan lava dome
Koasama lava dome
Hanareyama lava dome
Hotokeiwa stratovolcano
Hotokeiwa Lava
Maekake stratovolcano
Takatsuya stratovolcano
Okuwa Debris Avalanche Deposit
Tsumagoi Pyroclastic Flow Deposit
Kusatsu-Shirane volcano
1st stage
Matsuozawa volcano
Yumiike Lava
Komenashi Lava
Udogasawa Lava
Yahazudaira Lava
Aoba Lava
Matsuozawa Lava
Yatoko Lava
Shirane Tuff Breccia
2nd stage
Oshi Pyroclastic Flow Deposit
3rd stage
Heibeike Lava
Sarabuseyama volcano
Sarabuseyamanikurayama Lava
Nikurayama volcano
Sarabuseyamanikurayama Lava
Ayamedaira volcano
Suzugadake Lava
Shirodake volcano
Shirodake Lava
Mitsugamine Lava
Kesamaru volcano
Honkesamaru Lava
Maekesamaru Lava
Sukai volcano
Sukaiyama Lava
Kaminokai Clay Beds
Miyukida Fan Deposit
Hagiu Formation
Nodono Formation
Lower Agatsuma Loam
Ata-Th Tephra
Minohara Tephra
YoP-2 Tephra
Higher Terrace Deposit, Shirasuna river
Higher Terrace Deposit, Nurukawa river
Lower Terrace Deposit, Agatsuma river
Tazawa Formation
Higher Terrace Deposit, Watarase river
Middle Terrace Deposit, Watarase river
Lower Terrace Deposit, Watarase river
Kiribara Terrace Deposit
Iwajuku Terrace Deposit
Yabuzuka Terrace Deposit
Omama Terrace Deposit
Aioi Terrace Deposit
Nippa Terrace Deposit
Ishigami Terrace Deposit
Syori Terrace Deposit
Pleistocene - Holocene
Kusatsu-Shirane volcano
3rd stage
Shirane pyroclastic cone
Ainomine pyroclastic cone
Motoshirane pyroclastic cone
Yumi-ike maar
Shirane volcano
Keitsukasan Lava
Okkai Tephra
Holocene (0.01-0 Ma)
Haruna volcano
Younger Haruna volcano
Hr-FA Tephra
Haruna-Futatsudake-Shibukawa Pyroclastic Flow Deposit
Haruna-Futatsudake-Shibukawa Fall Tephra
Hr-FP Tephra
Haruna-Futatsudake-Ikaho Pyroclastic Flow Deposit
Haruna-Futatsudake-Ikaho Fall Tephra
Futatsudake Lava
Kanto loam formation
Upper loam formation
Asama-Eboshi volcanoes
Onioshidashi Lava
Kanbara Mudflow Deposit
Oiwake Pyroclastic Flow Deposit
Kusatsu-Shirane volcano
3rd stage
Kagusa Lava
Sessho Lava
Motoshirane Lava
Kumakura Pumice Bed
Hr-AA Tephra
As-C Tephra
As-B Tephra
As-A Tephra
Age unknown
Yunokuchi pumice bed (UP)
Maebashi formation
Hirosegawa formation
Wagobashi formation
Numata conglomerate formation
Hiuchigatake lava
Tadamigawa granite
Zazenyama lava
Okushiranekita lava
Okushiranechuo lava
Kono formation
Naritahara pumice bed? (RP)
Aoba lava
Geological structures
Kashiwazaki-Choshi tectonic line
Okitano-Iwayama fault