Group or Formation Period Notes Abasheva Formation Jurassic Abashevo Suite Formation Jurassic Abrekskaya Suite Formation Permian Acheshbok Formation Triassic Admiralty Formation Triassic Adz'va Formation Permian Agabyt Formation Triassic Agitkan Formation Triassic Agulak Suite Formation Jurassic Akachan Formation Permian, Carboniferous Akatievo Formation Carboniferous Akatuevskaya Formation Jurassic Akavassky Formation Carboniferous Akchalym Formation Silurian Akdurug Formation Cambrian Aksai Suite Formation Jurassic Aksaisk Formation Jurassic Aktash Formation Silurian Aktash Suite Formation Jurassic Aktasty Formation Permian Aleksandrovskii Formation Carboniferous Aleksin Formation Carboniferous Altatka Suite Formation Jurassic Aluginskaya Formation Paleogene Alykaevskaya Formation Carboniferous Alyutovo Formation Carboniferous Amanak Formation Permian Amanakskaya Formation Permian Amaninskaya Formation Paleogene Amata Formation Devonian Amba Formation Triassic Amkanzhin Formation Permian Amkin Formation Cretaceous Angachi Formation Silurian Antibes Formation Cretaceous Antiinsky Formation Permian Antiya Formation Permian Apsat Formation Cretaceous Arakay Group/Arakayskaya Formation Paleogene Arakay Group/Gastellovskaya Formation Paleogene Arakay Group/Gennoyshinskaya Formation Paleogene Argun Formation Cretaceous Arkachan Formation Permian Arkagalinskaya Formation Cretaceous Asatausky Formation Carboniferous Askyn Formation Devonian Askynbashsky Formation Carboniferous Astronomicheskogo Mysa Formation Paleogene Atkan Formation Permian Ausinskaya Formation Neogene Avamskaya Suite Formation Permian Avlandian Formation Permian Ayach'yaga Formation Permian Ayak Suite Formation Jurassic Aykhal Formation Carboniferous Ayyuvinskiy Formation Carboniferous Babuk Formation Triassic Badin Formation Jurassic Bagan Formation Ordovician Baigendzhi Formation Permian Baigendzhin Formation Permian Baikur Formation Permian Baital Formation Silurian Baitugan Formation Permian Bajtugan Formation Permian Bakalinskian Suite Formation Permian Baksanii Formation Ordovician Balakhtison Formation Cambrian Baley Formation Cretaceous Barabash Formation Permian Barabashskaya Formation Permian Baraniy Formation Ordovician Barents Formation Carboniferous Basal and coal Formation Jurassic Batylykh Formation Cretaceous Bayan Kol Formation Cambrian Baytugan Formation Permian Bazaikha Formation Cambrian Bazanov and Bokhtin Suite Formation Jurassic Bazanovo and Bokhto Suites Formation Jurassic Bazarli Suite Formation Jurassic Bazhenov Formation Cretaceous Begichev Formation Cretaceous Beglyi Formation Permian Begunovskaya Formation Neogene Belalabinskaya Group/Nikitin Formation Permian Belalabinskaya Group/Urushten Formation Permian Belaya Kalitva Formation Carboniferous Belebeevo Formation Permian Belebei Formation Permian Belebeyeoskaya Suite Formation Permian Belkovskaya Formation Permian Belogorsk Formation Silurian Beloshchel'e Formation Permian Belovo Horizon Formation Devonian Belushkin Formation Permian Belushkinskaya Suite Formation Permian Belyi Yar Formation Carboniferous Berchogur? Formation Devonian Bereza Beds Formation Cretaceous Berge Suite Formation Jurassic Berikul Formation Cambrian Bezymyanny Formation Permian Biertdag Formation Devonian Bilir Formation Cambrian Bitak Suite Formation Jurassic Bizovskaya Suite Formation Permian Blinovo Formation Neogene Bochara Formation Permian Boets Formation Permian Boguchan Formation Permian Boguchany Formation Permian Bokhtin Formation Jurassic Bokhto Suite Formation Jurassic Bol'shaya Kheta Group/Nadoyakh Formation Jurassic Bol'sheishin Formation Cambrian Bolshekinelskaya Formation Permian Bolshesininskaya Series Group/Mishayagskaya Suite Formation Triassic Bolshesininskaya Series Group/Vyatkinskaya Suite Formation Triassic Borodino Suite Formation Jurassic Botchi Formation Neogene Britvinskaya Series Formation Permian Bugali Formation Permian Bugarikta Formation Triassic Bugryshikhinskaya Formation Ordovician Bukachacha Formation Cretaceous Bukobai Formation Triassic Bukobaiskaya Suite Formation Triassic Bukobay Formation Triassic Bukukun Formation Jurassic Bukukun Suite Formation Jurassic Bulunkan Formation Triassic Buregi Formation Devonian Burgali Formation Permian Burguklinskaya Formation Permian Burguklinskaya Suite Formation Permian Burkguklinian suite Formation Permian Burskii Formation Ordovician Burtsevsky Formation Permian Byankino Formation Jurassic Byankinskaya Formation Jurassic Bykov Formation Cretaceous Byrranga Formation Permian Bystraya Formation Cambrian Bytantay Formation Permian Byzovaya Formation Triassic Cabanin Horizon Formation Devonian Cape Zhurinskiy outcrop Formation Cambrian Carbonate Formation Triassic Carbonate, Clastic carbonate Formation Triassic Chagachan Suite Formation Jurassic Chakyr Formation Ordovician Chalmak Formation Silurian Chambin Formation Permian Chandalaz Formation Permian Charkabozh Formation Triassic Chebalsinskaya Formation Permian Chechuma Suite Formation Jurassic Chegitun Formation Ordovician Chekhan Formation Cambrian Chelyabinskaya Series Group/Kalachevskaya Suite Formation Triassic Chelyabinskaya Series Group/Korkinskaya Suite Formation Triassic Chelyabinskaya Series Group/Kozirevskaya Suite Formation Triassic Chepa Suite Formation Jurassic Cheremkhovo Formation Jurassic Cheremkhovo Suite Formation Jurassic Cheremkhovskaya Formation Jurassic Cheriyusskaya Suite Formation Permian Chernaya Bay Horizon Formation Devonian Chernorechian Suite Formation Permian Chernovskaya Group/Doronino Formation Cretaceous Cherpel' Suite Formation Jurassic Chertovskia Formation Ordovician Chichikan Formation Triassic Chigan Formation Cretaceous Chikoi Formation Neogene Chinka Formation Permian Chisyan Formation Permian Chochaskaya Suite Formation Permian Chopko Formation Cambrian Chusovitino Suite Formation Jurassic Cladochonus Limestone Formation Permian Clastic carbonate Formation Triassic Coal Suite Formation Jurassic Conglomerate Suite Formation Jurassic Coryphyllia Beds Formation Triassic Dadoy Formation Permian Daekhuriin Group/Daekhuriinskaya Formation Paleogene Daekhuriin Group/Mutnovskaya Formation Paleogene Dagi Group/Agnevskaya Formation Neogene Dagi Group/Daginskaya Formation Neogene Dainskaya Formation Cretaceous Dal'nii Suite Formation Jurassic Daratuiskiy Formation Permian Dashtygoi Formation Silurian Dashtygoi Beds Formation Silurian Daya Formation Cretaceous Degali Formation Permian Degibadam Suite Formation Jurassic Delendzha Formation Permian Delendzhin Formation Permian Delenzhinskaya Suite Formation Permian Dem'yanovskaya Formation Triassic Dep Suite Formation Jurassic Dietken Formation Ordovician Div'ya Formation Permian Djaskoian Formation Jurassic Dmitriyevskaya Formation Cambrian Dolborskii Formation Ordovician Dolgan Formation Cretaceous Domanik Formation Devonian Donguz Formation Triassic Dulankhora Suite Formation Jurassic Dulgalakh Formation Permian Dulgalakhskaya Suite Formation Permian Duraisk Formation Jurassic Durnayu Formation Silurian Dvuroginskaya Suite Formation Triassic, Permian Dyby Formation Permian Dzharsu Suite Formation Jurassic Dzhaskoi Suite Formation Jurassic Dzhelon Suite Formation Jurassic Dzheltin Formation Permian Dzheltinskaya Formation Permian Dzhiakunian Formation Permian Dzhigdali Formation Permian Dzhil' Suite Formation Jurassic Dzhuptagin Formation Permian Echii Formation Permian Echinosphaerites Chalk Formation Ordovician Echiy Formation Permian Edzhid Formation Carboniferous Efremov Formation Permian Eksenya Formation Cretaceous Ekushanskaya Suite Formation Permian El'gyan Formation Cambrian Elegest Suite Formation Jurassic Elets Formation Devonian Emanra Formation Cretaceous Emjaksin Formation Cambrian Emyaksin Formation Cambrian Endybal Formation Permian Endybal Formation Permian Enemtenskaya Formation Neogene Er Formation Permian Erbek Suite Formation Jurassic Erkeket Formation Cambrian Ermanovka Group/Etolon Formation Neogene Ermanovskaya Formation Neogene Erunakov Formation Permian Erunakovskaya Group/Gramoteinskaya Formation Permian Erunakovskaya Group/Leninskaya Formation Permian Etolon Formation Neogene Etolonskaya Formation Neogene Evenkskaya Formation Permian Evlanovo Formation Devonian Evtropina Formation Devonian Ezhovyi Formation Neogene Fedorovskiy Formation Permian Filipp'el Formation Silurian Fol'k Formation Permian Gabdrashidov Formation Permian Gabdrashitovian Suite Formation Permian Gabdrashitovian Suite? Formation Permian Gabirut and Dzhizhikrut Suites Formation Jurassic Gakkhinskaya Formation Paleogene Galindai Formation Permian Gamskaya Group/Yarenskian Formation Triassic - Ganin Formation Devonian Gankin Formation Cretaceous Gapshima Formation Cretaceous Gazov Formation Permian Gerkinskaya Formation Permian Getkilninskaya Formation Paleogene Gidarin Formation Jurassic Gidarinskaya Formation Cretaceous Gizhiga Formation Permian Glubokaya Formation Devonian Glushinskaya Formation Jurassic Glushkovo Formation Jurassic Godymboy Formation Cretaceous Godymboyskaya Formation Cretaceous Golomyannyj Formation Silurian Gorbiyachin Formation Cambrian Gorbousha Formation Cretaceous, Jurassic Goryachikh Klyuchey Formation Neogene Granatovoya Formation Neogene Greben Formation Silurian Gremyashchij Formation Devonian Gundara Formation Cretaceous Gurimisskaya Suite Formation Triassic Gurud Suite Formation Jurassic Gusinaya Formation Permian Gusinozemelskaya Formation Permian Herbesskaya Formation Carboniferous Holmsk Formation Neogene Holodnolog Formation Permian Honto Formation Neogene Honto Group/Aushi Formation Neogene Honto Group/Hacchorei Formation Neogene Ichetuy Formation Jurassic Ichetuy Suite Formation Jurassic Il'chir Formation Cambrian Il'inskaya Formation Neogene Il'inskaya Formation Permian Il'inskaya Formation Permian Il'inskaya Group/Uskatskaya Formation Permian Il'khatunskaya Formation Paleogene Ilanskaya Suite Formation Jurassic Ilek Formation Cretaceous Ilibei Formation Permian Ilibeiskaya Formation Permian Imtachan Formation Permian Inta Formation Permian Intian Suite Formation Permian Ionayskaya Formation Paleogene Irbitey Formation Cambrian Irbychan Formation Permian Iren Formation Permian Irga Formation Permian Ishanovskaya Formation Permian Ishanovskaya Suite Formation Permian Itat Formation Jurassic Itat Suite Formation Jurassic Iva Formation Permian Kabanka Formation Silurian Kadyr Formation Jurassic Kakanaut Formation Cretaceous Kakertskaya Formation Neogene Kalenda Suite Formation Jurassic Kalga Suite Formation Jurassic Kalgan Formation Jurassic Kalinovka Formation Permian Kalitvenskaya Formation Permian Kalvitza Formation Silurian Kalyan Formation Jurassic Kamala Suite Formation Jurassic Kamchikskaya Formation Paleogene Kamenka Bay Horizon Formation Devonian Kamennyi Yar Formation Triassic Kameshkovskiy Formation Cambrian Kamyshin Formation Paleogene Kamyshla Formation Permian Kamyshlinskie Formation Permian Kanarai Formation Jurassic Kangauz Formation Cretaceous Kanyon Formation Ordovician Karadan Formation Triassic Karadiirmen' Suite Formation Jurassic Karagan Formation Neogene Karakhem Formation Silurian Karalda Suite Formation Jurassic Karasinskaya Formation Ordovician Karazin Formation Triassic Kardasyn Suite Formation Jurassic Karmakula Formation Permian Karmyssian Suite Formation Permian Karpinsk Formation Devonian Kata Formation Carboniferous Katanga Formation Cambrian Kazan Formation Permian Kazankovo Formation Permian Kazankovo Formation Permian Kazarka Formation Carboniferous Kech'pel Formation Permian Kedrovsk Formation Russian Federation Kemerovskaya Formation Permian Kemerovskaya Suite Formation Permian Kemskaya Formation Cretaceous Keryamaelskaya Suite Formation Triassic Kessyusa Formation Cambrian Keteme Formation Cambrian Khabakh Formation Permian Khabakhskaya Suite Formation Permian Khakanchanskaya Suite Formation Permian Khalagai Formation Neogene Khalalin Formation Permian Khaldzhin Formation Permi