List of geological units in Hokkaido

Fukagawa group: Bibaushi formation; Ichinosawa formation; Horokaoshirarika formation; Ebeotsu formation; Inadazawa formation; Samebuchi formation; Horokura formation; Chippubetsu formation; Ichiyan formation

Takigawa formation

Minenobu formation

Kiyomappu formation

Mochikubetsu formation

Honhorobetsu formation

Shotonbetsu formation

Nakatonbetsu formation

Kawanishi formation

Ugetsuzawa welded tuff bed

Horokayubetsu formation (Horokayubetsu welded tuff bed)

Horo formation

Ishiyama formation

Noboribetsu volcano: Tachibanaike lava; Raibayama lava

Yoichi formation

Tomarugawa Formation

Pliocene-Pleistocene

Teineyama Debris Avalanche Deposit

Tate formation

Makomanai formation

Yuchi Formation

Quaternary

Nisshin formation

Pleistocene (2.58- 0.01Ma)

Kutcharo volcano

Furume Welded Tuff

Kutcharo Tephra: KpI (Kutcharo Pumice Flow Deposit I; KpII (Kutcharo Pumice Flow Deposit II; KpIII (Kutcharo Pumice Flow Deposit III; KpIV (Kutcharo Pumice Flow Deposit IV; KpV (Kutcharo Pumice Flow Deposit V; KpVI (Kutcharo Pumice Flow Deposit VI; KpVII (Kutcharo Pumice Flow Deposit VII; KpVIII (Kutcharo Pumice Flow Deposit VIII

Post-Kutcharo caldera volcanoes

Mashu volcano

Stratovolcano building stage: Ma-α; Ma-β; Ma-γ; Ma-δ; Ma-ε; Ma-ζ

Nakajima volcano

Atosanupuri volcano

Older Atosanupuri Volcano: Atosanupuri Somma Lava; Oyakkotsu Lava Dome; Atosanupuri Pyroclastic Flow Deposit

Lower Mashu Tephra Formation: Ml-a; Ml-b; Ml-c; Ml-d; Ml-e

Chanai Tephra Formation

Ch-a: Ch-a1; Ch-a2

Ch-b: Ch-b1; Ch-b2

Ch-c

Ch-d: Ch-d4

Upper Nakashumbetsu Tephra Formation

Nu-e: Nu-e1; Nu-e2

Nu-f

Nu-g: Nu-g1; Nu-g2

Nu-h: Nu-h1; Nu-h2

Nu-i: Nu-i1; Nu-i2; Nu-i3; Nu-i4; Nu-i5

Nu-l: Nu-l3; Nu-l4; Nu-l5

Nu-n: Nu-n1

Nu-o

Nu-p: Nu-p1; Nu-p2; Tokotan Pumice Formation (Nu-p3); Nu-p5

Taisetsu Volcano Group

Asahidake Subgroup

Asahidake volcanic edifice

Early stage

E-2: Asahidake Summit Pyroclastic Rock; Banno-sawa Pyroclastic Rock and Lava; Asahidake Upper Pyroclastic Rock and Lava; Susoaidaira Pyroclastic Rock and Lava; Jigoku-daki Lava and Pyroclastic Rock; Asahidaira Lava and Pyroclastic Rock

E-1: Asahidake West Upper Lava and Pyroclastic Rock; Asahidake West Lower Lavas; Asahidake South Lavas

Ushiro-Asahidake volcanic edifice: Ushiro-Asahidake Lavas

Kumagatake volcanic edifice: Kumagatake No.3 Crater Pyroclastic Rock; Kumagatake Upper Lava and Pyroclastic Rock; Kumagatake Lower Pyroclastic Rock and Lava

Ohachidaira Caldera Eruption Deposit: Hx-type Pyroclastic Flow Deposit; Hb-type Pyroclastic Flow Deposit

Pon-Asahidake volcanic edifice

Oshima-Kojima volcano

Stage 3: Yamase-domari Lavas; Ai-domari Lavas; Benten-no-hana Lavas

Stage 2: Takino-ma Pyroclastic Rocks

Stage 1: Gome-saki Pyroclastic Rocks; Dai-Hiyakujima Intrusive Rock

Toya volcano

Toya Pyroclastic Flow Deposit: Tpfl I Unit; Tpfl II Unit; Tpfl III Unit; Tpfl IV Unit

Osarugawa Tephra

Usu volcano

Usu-b Tephra: Us-b1; Us-b2; Us-b3; Us-b4; Us-b5; Us-b6

Usu-a pumice bed (Us-a): Us-Ia; Us-IIa; Tateiwa pyroclastic flow deposit (Us-IIIa); Bunsei pyroclastic flow deposit (Us-IVa); Us-Va

Donkoroyama scoria cone

Kousuyama lava dome

Ousuyama lava dome

Usu somma lava

Nakajima volcano: Nj-Sk Tephra; Nakajima-Osarugawa Tephra

Kuttara volcano: Kt-1 Tephra; Kt-2 Tephra; Kt-Tk Tephra; Kt-3 Tephra (Kuttara-3 Tephra); Kt-Hy Tephra; Kt-4 Tephra (Kuttara-4 Tephra); Kt-6 Tephra (Kuttara-6 Tephra); Kt-7 Tephra; Kt-8 Tephra

Shikotsu volcano

Shikotsu Pyroclastic Flow Deposit

Shikotsu-1 Tephra

Shikotsu-3 pumice bed (Spfa-3)

Shikotsu-4 pumice bed (Spfa-4)

Shikotsu-5 Tephra

Shikotsu-6 Tephra

Shikotsu-7 pumice bed (Spfa-7, Shikotsu scoria bed)

Shikotsu-8 pumice bed (Spfa-8)

Shikotsu-9 pumice bed (Spfa-9)

Shikotsu-10 pumice bed (Spfa-10)

Shadai Tephra

Shadai Pyroclastic Flow Deposit

Eniwa volcano: Eniwa-a Tephra; Eniwa-b Tephra; Eniwa-c Tephra

Shiribetsu volcano: Kimobetsu Pyroclastic Flow Deposit; Shiribetsu Tephra

Yotei volcano: Y11 Tephra (Yotei-1 scoria bed, Yo.Ps-1); Y16 Tephra (Yo.Ps-2); Y25 Tephra (Yotei-3 scoria bed, Yo.Ps-3); Mpfa1 Tephra

Ishikaritakaoka formation

Dateyama formation: Shishinai formation

Sapporo Fan Deposit

Ebetsu Sand Formation

Motonopporo Clay Formation

Nopporo Group

Upper: Konopporo Formation; Momijidai Formation; Hongo Formation

Lower: Shimonopporo Formation

Takeyama Formation

Otoebetsugawa Formation

Uranosawa Formation

Zaimokuzawa Formation

Hakken Formation

Yamaguchi Formation

Tarukawa Formation

Hayakita formation

Karurusu clay bed

Shiretokomisaki formation

Utoro formation

Shiretokoiozan volcano: Ubushinottakabu lava; Shiretokoiozanchubu lava; Shiretokoiozanjobu lava

Unabetsudake volcano: Unabetsudakeshinki lava; Unabetsudakekyuki lava I; Unabetsudakekyuki lava II

Gotenyama lava

Fumizuki formation

Tomikawa formation

Ishikura formation

Zenigamezawa pyroclastic flow deposit

Setana formation

Oyachi formation

Ksfl

Kpfa-2

Kpfa-3

Kpfa-4 (Nishiki-2 pumice bed)

Kpfa-5 (Nishiki-1 pumice bed)

Aso-4 tuff bed (Aso-4)

Kpfl-1

Kpfl-2

Kpfl-3

Ng-a

Tpfa

Sipfa-1

Sipfa-2

Shikotsu old sand dune deposit (Izumi sand dune deposit)

Shikotsu old sand dune deposit

Eniwa old sand dune deposit: I; II; III; IV; V

Kochien formation

Tokachi Group: Nakazato Formation; Shibusan Formation; Oribeyama Formation; Osarushinai Formation

Osarushinaigawa Formation

Tokachigaoka Formation: Tokachigaoka Tuffaceous Sand Member

Chiyoda Formation

Iwamatsu Formation

Shikaribetsu-2 pumice bed (Uguisuiro pumice bed)

Shikaribetsu volcano: Petoutorusan lava

Tokachimitsumata caldera: Tokachimitsumata Pyroclastic Flow Deposit; Tokachimitsumata Pyroclastic Fall Deposit

Tokachimitsumata Formation

Gunkanyama Lava

Penkenikoro welded tuff bed

Tokachibuto Formation

Kamishikaribetsu Pyroclastic Flow Deposit

Kamiasahigaoka Pyroclastic Flow Deposit

Tokachigawa formation

Biraotori formation: Horokayanto formation

Biman Gravel Bed

Aso welded tuff bed (AWT, Kuro tuff)

Akan pyroclastic flow deposit: Akan upper pyroclastic flow deposit (AUP); Akan lower pyroclastic flow deposit (ALP)

Kushiro Group

Toya Formation

Kushiro Formation: Toro Member; Takkobu Member

Shiroyama Formation

Otanoshike Formation

Miyajima Formation

Furenko formation

Bekanbeushigawa formation

Konsen formation

Furume pyroclastic flow deposit (Furume welded tuff bed)

Kusharo-shoro tuff bed (KSr)

Kusharo-horoiwa tuff bed (KHr)

Big pumice bed (Big Pm)

Ganpen pumice bed (Ganpen Pm)

Sanshoku tuff bed

Kiyosato-1 pumice bed

Kiyosato-2 pumice bed

Kuchoro formation

Bihoro formation

Horoiwa tuff bed

Toetoko tuff bed

Monbetsu-1 tuff bed

Monbetsu-2 tuff bed

Urausu formation

Higashichitose formation

Kakuta formation

Shiomi formation

Moseushi formation

Mukawa-3 pumice bed (Mpfa-3)

Azuma tuff bed

Tokachi Pyroclastic Flow Deposit

Kushuko formation

Yunputo shell bed

Keihoku formation

Wankonosawa pumice bed

Chikubetsu terrace deposit

Tomamae terrace deposit

Kamisarufutsu formation

Ponnitachinai formation

Asajino formation

Okhotsk loam bed

Fukinodai formation

Furen formation

Hatsuchashinai formation

Biei welded tuff bed

Sangoku Formation

Shiitokoro Lava

Tokorogawa Formation

Tonokari formation

Shirataki formation (Shirataki welded tuff bed)

Antaromagawa welded tuff bed

Aizankei welded tuff bed

Tokachidake volcano: Younger stage 1; Middle stage; Older stage; OKina lava

Orangeiro-1 tuff bed (Op-1)

Orangeiro-2 tuff bed (Op-2)

Orangeiro-3 tuff bed (Op-3)

Poanyoro pumice flow deposit

Poanyoro pumice bed

Kasabetsu formation

Noboribetsu pumice bed

Noboribetsu welded tuff bed

Noboribetsu formation

Ranpoge pumice bed

Nittaporo formation

Misato formation

Shimoabira formation

Shiomi formation

Maruyama formation

Shinkawa formation

Wattsu formation

Nishinosato formation

Hiroshima formation

Atsubetsu formation

Rishiri volcano

Final stage: Tanetomi Lava; Kutsugata Lava; Nozuka Lava; Senhoshi Lava; Nocchu Pyroclastics

Climactic stage: Ishiyama Lava Dome; Main part of stratovolcano; Chokan'yama stratovolcano

Initial stage

Lower part of stratovolcano

Lava dome group: Pon'moshirito Lava Dome; Peshi-misaki Lava Dome; Oshidomari-pon'yama Lava Dome; Fujino Lava Dome

Minamihama Lava

Oshidomari Lava

Tanetomi lava

Kutsugata lava

Giboshinuma lava

Nozuka lava

Ichinosawa scoria cone

Komagatake volcano

Stage II: P3; P4; P5; P6; P7; Ko-h

Stage I: Ko-i; Numajiri Debris Avalanche Deposit; P8; Matsuyazaki Debris Avalanche Deposit; Kengamine Lava; Sawaradake Agglutinate; Komagatake Debris Avalanche Deposit

Ak6: Ak6-a; Ak6-b; Ak6-c; Ak6-d

Ak7: Ak7-a; Ak7-b; Ak7-c; Ak7-d; Ak7-e

Ak8

Ak9: Ak9-a; Ak9-b; Ak9-c

Ak10

Ak11

Ak12: Ak12-a; Ak12-b; Ak12-c

Ak13: Ak13-a; Ak13-b

Ak14: Ak14-a; Ak14-b; Ak14-c; Ak14-d; Ak14-e; Ak14-f; Ak14-g

Ak15: Ak15-a; Ak15-b; Ak15-c; Ak15-d; Ak15-e; Ak15-f

Kuchoro Pyroclastic Flow Deposit

LowK-2

LowK-1

Pleistocene-Holocene

Nishihama Bed

Shikotsu volcano: Fuppushi volcano

Maruyama volcanic products

Nipesotsu volcanic products

Holocene (0.01-0 Ma)

Rishiri volcano

Final stage: Numaura Pyroclastics

Kutcharo volcano

Post-Kutcharo caldera volcano

Atosanupuri volcano

Younger Atosanupuri Volcano

Atosanupuri I Lava Domes: Maruyama Lava Dome; Nupuriondo Lava Dome; 274m-yama Lava Dome; Nifushioyakotsu Lava Dome; Tosamoshibe Lava Dome; Optateshuke Lava Dome

Atosanupuri II Lava Domes: Rishiri Lava Dome; Rishiri Pyroclastic Flow Deposit; Sawanchisappu Lava Dome; Makuwanchisappu Lava Dome; Atosanupuri Older Lava Dome; Atosanupuri Younger Lava Dome

Mashu volcano

Central cone building stage

Upper Mashu Tephra Formation

Ma-b: Ma-b5

Ma-c

Ma-d

Ma-e

Caldera forming stage

Upper Mashu Tephra Formation: Mashuko pyroclastic flow deposit (Ma-f); Mashu-g pumice bed (Ma-g); Mashu-h pumice bed (Ma-h); Mashu-i pumice bed (Ma-i); Ma-j; Ma-k; Ma-l

Taisetsu Volcano Group

Asahidake Subgroup

Asahidake volcanic edifice

Late stage: Jigokudani Volcaniclastic Rock 2; Jigokudani Volcaniclastic Rock 1

Shikotsu volcano

Tarumae volcano

Year1874 fall bed (Tarumae volcano)

Tarumae-a Tephra

Tarumae-b Tephra

Tarumae-c Tephra: Tarumae-c1 pumice bed (Ta-c1, Tarumae-c1 tuff bed); Tarumae-c2 pumice bed (Ta-c2, Tarumae-c2 tuff bed)

Tarumae-d Tephra

Kiiro pumice bed (Us-c)

Baitoushan-Tomakomai Tephra

Showashinzan volcano: Lava dome

Atsuma formation

Shiretokoiozan volcano: Shiretokoiozan debris flow deposit; Namakoyama lava dome; Nanpo lavadome

Sasihruidake lava

Me-a

Komagatake volcano

Stage IV: 1942; Ko-a; Ko-c1; Ko-c2; Ko-d; Kurumizaka Debris Avalanche Deposit

Stage III: Ko-f; P1; P2; Ko-g

Es-2

Motomura pyroclastic flow deposit

Tokachi-c1tuff bed (To-c1)

Tokachi-c2 tuff bed (To-c2)

Meakan-a1 tuff bed

Meakan-a2 tuff bed

Meakan-a3 tuff bed

Meakan-b scoria bed

Rawan pyroclastic flow deposit

Atosanupuri lava dome

Hotoku tuff bed

Shizen shell bed

Wakkaoi formation

Tateyama loam bed

Zenkoji lahar deposit

Noboribetsu volcano: Hiyoriyama lava dome; Oyunuma volcanic product; Jigokudani volcanic product; Kuttara pyroclastics bed; Kitayama lava

Niikappu mud volcano

Tokachidake volcano

Younger stage 2

Volcanic Fan 3 Deposit

1926AD Lahar Deposit: Unit A; Unit B; Unit C

Ground Crator Pyroclastic Flow Deposit 0

Shirogane Mudflow Deposit

Ground Crator Pyroclastic Flow Deposit 1

Ground Crator Pyroclastic Flow Deposit 2

Age unknown

Chashikotsunai Formation

Penke Formation

Koganeyu andesite

Hyakumatsuzawa quartz porphyry

Hyakumatsuzawa formation

Moiwayama volcano

Moiwayama lava: Moiwayama-I lava; Moiwayama-II lava; Moiwayama-III lava

Gunkanmisaki lava

Rusutsu pyroclastic flow deposit

Chisenupuri debris flow deposit

Hongo formation

Horoman peridotite

Oshinkoshin intrusion

Unabetsudake volcano: Unabetsudake873mpeak lava dome; 735.3mpeak lava; Kounabetsudake dike; Kounabetsudake pyroclastic rocks; Kounabetsudake lava

Tachimachimisaki lava

Koryuji lava

Mohejigawa formation

Esan lava dome

Futoro formation: Tsukunai member

Shikaribetsu-1 pumice bed (Tangara pumice bed)

Kamishihoro formation

Kitaoribe formation

Kamihoroka welded tuff bed

Uesakayama formation

Higashimeto tuff bed

Kakkomi tuff bed

Osatsube formation

Meakan volcano: Meakanfuji lava; Ponmachineshiri lava; Nakamachineshiri lava; Nakamachineshiri somma lava; Kengamine lava; Sanchobu lava dome; Futatsudake lava; Meakandake lava; Furebetsukazan950mpeak lava

Rausudake volcano: Rausudaira lava; Rausudake lava dome; Rausudake lava

Abashiri tuff bed

Horonari trondhjemite

Takadomari serpentinites

Irumukeppu volcano: Otoeyama lava; 800msan lava; Okirikawa lava; Irumukeppu lava; 805msan lava; Okirikawakosenzawa lava

Raijo formation

Ochiai formation

Penke lava

Shirogane formation

Shirogane lava

Shirataki granite

Shirataki bodies

Esan volcano: Misaki lava

Choshimisaki formation

Otoebetsugawa formation

Takinoue welded tuff bed

Maruyama lava

Nakagawa formation

Furano formation

Geological structures

Hidaka main thrust

Tobetsu fault

Izumisato fault

Naganuma fault

Yakumo fault

Oribe fault

Satsunaigawa-Otofukegawa fault

Urahoro fault

Kotanuka fault

Sakaemori fault

Omagari fault

Nayoro fault

Chiebun fault

Rokugo fault

Abashiri tectonic line: Urahoro fault

Abashirikotoho faults

Bannosawa thrust

Urausu fault

Yamabe fault

Oribe fault

Shirataki tectonic line

Kamishiyubetsu tectonic line

Tokachichuo tectonic zone

Shunbetsu anticline

Sarubetsu anticline

Shintotsukawa anticline

Otanikaigan anticline

Sorachi anticline

Tobetsu syncline

Oshirarika syncline

Chikubetsu syncline

Hatonosu dome

Manji dome

Harutoritaro clastic dike