Present

0 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Precambrian

1001 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Archean

1007 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Paleoarchean

1009 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Mesoarchean

1010 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Neoarchean

1011 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Proterozoic

1012 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Rhyacian

1015 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Orosirian

1016 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Statherian

1017 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Mesoproterozoic

1018 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Ectasian

1020 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Stenian

1021 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Neoproterozoic

1022 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Cryogenian

1024 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Ediacaran

1025 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper Edicaran

1027 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Phanerozoic

1028 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Tommotian

1033 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Lenian

1035 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Amgaian

1037 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Mayaian

1038 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Jiangshanian

1041 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Stage10

1042 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Ordovician

1043 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Middle Ordovician

1047 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Llanvirn

1048 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Llandeilo

1049 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Ordovician

1050 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Ashgill

1054 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Lower Ashgill

1055 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Silurian

1057 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Aeronian

1060 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Telychian

1061 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Wenlock

1062 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Homerian

1064 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Ludlow

1065 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Ludfordian

1067 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Pridoli

1068 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Devonian

1070 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper Lochkovian

1074 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Pragian

1075 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper Pragian

1077 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Emsian

1078 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Upper Emsian

1080 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Middle Devonian

1081 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Eifelian

1084 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Givetian

1085 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Givetian

1087 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Devonian

1088 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Upper Frasnian

1091 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Famennian

1092 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Famennian

1094 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Carboniferous

1095 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Upper Tournaisian

1099 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Visean

1102 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Namurian C

1107 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Westphalian

1108 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Westphalian A

1109 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Westphalian B

1110 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Westphalian D

1112 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Stephanian A

1114 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Stephanian B

1115 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Permian

1117 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Mesozoic

1124 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Olenekian

1128 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper Olenekian

1130 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Middle Triassic

1131 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Anisian

1134 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Ladinian

1135 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Upper Ladinian

1137 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Upper Triassic

1138 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Upper Carnian

1141 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Norian

1142 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Upper Norian

1144 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Rhaetian

1145 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper Rhaetian

1147 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Jurassic

1148 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Middle Hettangian

1152 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper Hettangian

1153 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Sinemurian

1154 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Upper Sinemurian

1156 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Pliensbachian

1157 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Upper Pliensbachian

1159 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Toarcian

1160 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Middle Toarcian

1162 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper Toarcian

1163 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Middle Aalenian

1167 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Aalenian

1168 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Bajocian

1169 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Bajocian

1171 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Bathonian

1172 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Middle Bathonian

1174 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Upper Bathonian

1175 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Callovian

1176 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Middle Callovian

1178 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Upper Callovian

1179 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Middle Oxfordian

1183 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper Oxfordian

1184 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Kimmeridgian

1185 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper Kimmeridgian

1187 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Tithonian

1188 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Middle Tithonian

1190 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Upper Tithonian

1191 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Cretaceous

1192 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Middle Berriasian

1197 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Upper Berriasian

1198 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Valanginian

1199 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Upper Valanginian

1201 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Hauterivian

1202 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Upper Hauterivian

1204 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Barremian

1205 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Barremian

1207 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Aptian

1208 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Aptian

1211 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Albian

1212 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Middle Albian

1214 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Albian

1215 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Upper Cretaceous

1216 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Middle Cenomanian

1219 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Cenomanian

1220 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Turonian

1221 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Middle Turonian

1223 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Upper Turonian

1224 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Coniacian

1226 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Middle Coniacian

1228 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Coniacian

1229 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Santonian

1230 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Middle Santonian

1232 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Santonian

1233 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Campanian

1234 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Middle Campanian

1236 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Campanian

1237 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Maastrichtian

1238 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Maastrichtian

1240 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Cenozoic

1241 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Selandian

1247 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Thanetian

1248 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Eocene

1249 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Upper Ypresian

1253 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Lutetian

1255 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Middle Lutetian

1257 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Upper Lutetian

1258 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Bartonian

1259 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Upper Bartonian

1261 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Priabonian

1263 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Oligocene

1264 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Chattian

1268 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Neogene

1269 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper Aquitanian

1274 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Burdigalian

1275 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Upper Burdigalian

1277 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Langhian

1279 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Serravallian

1280 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Tortonian

1282 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Messinian

1283 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Pliocene

1284 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Piacenzian

1288 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Quaternary

1289 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Praetiglian

1292 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Tiglian

1293 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Eburonian

1294 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Waalian

1295 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Menapian

1296 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Bavelian

1297 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Cromerian

1298 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Middle Pleistocene

1299 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Cromerian I

1301 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Glacial a

1302 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Cromeriann II

1303 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Glacial b

1304 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Cromerian III

1305 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Glacial c

1306 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Cromerian IV

1307 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Elsterian

1308 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Holsteinian

1309 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Saalian

1310 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Fuhne

1311 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Wacken/Dömnitz

1312 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Drenthe

1313 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Saale/Warthe

1314 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Warthe

1315 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper/Late Pleistocene

1316 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Weichselian

1318 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Early Weichselian

1319 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Middle Weichselian

1320 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Lower Pleniglacial

1321 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Interpleniglacial

1322 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Upper Weichselian

1323 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Upper Pleniglacial

1324 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Late Glacial

1325 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Holocene

1326 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Boreal

1328 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Atlantic

1329 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Subboreal

1330 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Subatlantic

1331 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Icartian

2002 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Paleoproterozoic

2003 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Sturtian

2007 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Vendian

2008 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Stage2

2014 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Series2

2016 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Stage4

2018 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Miaolingian

2019 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Drumian

2021 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Guzhangian

2022 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Furongian

2025 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Floian

2034 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Darriwilian

2036 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Katian

2038 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Hirnantian

2039 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Couvinian

2044 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Middle Mississippian

2047 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Upper Mississippian

2048 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Strunian

2052 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Ivorian

2053 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Livian

2056 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Arundian

2057 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Holkerian

2058 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Asbian

2059 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Brigantian

2060 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Warnantian

2061 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Pennsylvanian

2067 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Middle Pennsylvanian

2069 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Upper Pennsylvanian

2070 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Gzhelian

2074 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Sakmarian

2080 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Artinskian

2081 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Kungurian

2082 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Guadalupian

2085 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Wordian

2087 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Capitanian

2088 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Lopingian

2089 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Changhsingian

2091 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Lotharigian

2117 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Domerian

2120 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Middle Jurassic

2121 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Upper Jurassic

2122 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Astartian

2128 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Sequanian

2129 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Pterocerian

2130 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Virgulian

2131 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Middle Volgian

2138 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Upper Volgian

2139 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Portlandian

2140 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Lower Portlandian

2141 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper Portlandian

2142 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Purbeckian

2143 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Purbeckowealdian

2144 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Gargasian

2151 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Clansayesian

2152 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Vraconian

2154 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Fuvelian

2164 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Danomontian

2169 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Montian

2170 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Heersian

2171 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Cuisian

2174 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Ledian

2177 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Wemmelian

2178 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Assian

2180 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Marinesian

2182 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Orleanian

2191 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Astaracian

2195 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Savignean

2196 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Redonian

2201 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Poederlian

2211 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Reuverian B

2214 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Reuverian C

2215 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper Villafranchian

2218 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Biber

2220 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Biber/Donau Interglacial

2221 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Calabrian

2222 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Emilian

2224 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Sicilian

2225 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Donau

2226 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Donau/Gunz Interglacial

2227 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Gunz

2228 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Gunz/Mindel Interglacial

2230 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Mindel

2231 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Mindel/Riss Interglacial

2232 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Riss

2233 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Wurm

2237 

geochronologic boundary
, Concept
, era boundary

experimental

Base of Würm I

2238 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Würm II

2239 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Würm III

2240 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Würm IV

2241 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Oldest Dryas

2242 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Bølling

2243 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Older Dryas

2244 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Allerød

2245 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Younger Dryas

2246 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Dienerian

3003 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Spathian

3005 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Middle Anisian

3007 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Bithynian

3008 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Pelsonian

3009 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Illyrian

3010 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Longobardian

3012 

Concept
, era boundary
, geochronologic boundary

experimental

Base of Tuvalian

3014 

era boundary
, geochronologic boundary
, Concept

experimental

Base of Alaunian

3016 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Sevatian

3017 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Middle Holocene

3020 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Upper/Late Holocene

3022 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Paniselian

3026 

era boundary
, Concept
, geochronologic boundary

experimental

Base of Toyonian

3028 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Botomian

3029 

Concept
, geochronologic boundary
, era boundary

experimental

Base of Middle Visean

3030 

geochronologic boundary
, era boundary
, Concept

experimental

Base of Middle Norian

3032 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GS26

3036 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI25c

3037 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GI25b

3038 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI25a

3039 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GS25

3040 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI24.2

3041 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GS24.2

3042 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI24.1c

3043 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI24.1b

3044 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GI24.1a

3045 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GS24.1

3046 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GI23.2

3047 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GS23.2

3048 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI23.1

3049 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GS23.1

3050 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GI22g

3051 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GI22f

3052 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI22e

3053 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GI22d

3054 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GI22c

3055 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GI22b

3056 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GI22a

3057 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GS22

3058 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GI21.2

3059 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GS21.2

3060 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GI21.1e

3061 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI21.1d

3062 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI21.1c

3063 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GI21.1b

3064 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI21.1a

3065 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GS21.1

3066 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI20c

3067 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI20b

3068 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI20a

3069 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GS20

3070 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI19.2

3071 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GS19.2

3072 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GI19.1

3073 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GS19.1

3074 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI18

3075 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GS18

3076 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI17.2

3077 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GS17.2

3078 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GI17.1c

3079 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GI17.1b

3080 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI17.1a

3081 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GS17.1

3082 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GI16.2

3083 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GS16.2

3084 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI16.1c

3085 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GI16.1b

3086 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GI16.1a

3087 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GS16.1

3088 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI15.2

3089 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GS15.2

3090 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GI15.1

3091 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GS15.1

3092 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GI14e

3093 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GI14d

3094 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GI14c

3095 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI14b

3096 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI14a

3097 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GS14QS

3098 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GI13c

3099 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GI13b

3100 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI13a

3101 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GS13

3102 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GI12c

3103 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GI12b

3104 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI12a

3105 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GS12

3106 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GI11

3107 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GS11

3108 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI10

3109 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GS10

3110 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI9

3111 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GS9

3112 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI8c

3113 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GI8b

3114 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI8a

3115 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GS8

3116 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI7c

3117 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GI7b

3118 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GI7a

3119 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GS7

3120 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GI6

3121 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GS6

3122 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GI5.2

3123 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GS5.2

3124 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI5.1

3125 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GS5.1

3126 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI4

3127 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GS4

3128 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GI3

3129 

geochronologic boundary
, Concept
, era boundary

experimental

Base of GS3

3130 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GI2.2

3131 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GS2.2

3132 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GI2.1

3133 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GS2.1c

3134 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GS2.1b

3135 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GS2.1a

3136 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GI1e

3137 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI1d

3138 

era boundary
, Concept
, geochronologic boundary

experimental

Base of GI1c3

3139 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GI1c2

3140 

era boundary
, geochronologic boundary
, Concept

experimental

Base of GI1c1

3141 

Concept
, geochronologic boundary
, era boundary

experimental

Base of GI1b

3142 

Concept
, era boundary
, geochronologic boundary

experimental

Base of GI1a

3143 

geochronologic boundary
, era boundary
, Concept

experimental

Base of GS1

3144 

Concept
, era boundary
, geochronologic boundary

experimental

End of Lenian

e1035 

era boundary
, Concept
, geochronologic boundary

experimental

End of Amgaian

e1037 

Concept
, geochronologic boundary
, era boundary

experimental

End of Mayaian

e1038 

era boundary
, geochronologic boundary
, Concept

experimental

End of Arenig

e1046 

Concept
, era boundary
, geochronologic boundary

experimental

End of Caradoc

e1051 

Concept
, geochronologic boundary
, era boundary

experimental

End of Upper Caradoc

e1053 

geochronologic boundary
, era boundary
, Concept

experimental

End of Namurian

e1104 

era boundary
, geochronologic boundary
, Concept

experimental

End of Namurian C

e1107 

Concept
, geochronologic boundary
, era boundary

experimental

End of Stephanian C

e1116 

geochronologic boundary
, era boundary
, Concept

experimental

End of Lower Olenekian

e1129 

geochronologic boundary
, era boundary
, Concept

experimental

End of Lower Anisian

e1133 

era boundary
, Concept
, geochronologic boundary

experimental

End of Lower Ladinian

e1136 

era boundary
, geochronologic boundary
, Concept

experimental

End of Lower Carnian

e1140 

era boundary
, Concept
, geochronologic boundary

experimental

End of Lower Norian

e1143 

geochronologic boundary
, Concept
, era boundary

experimental

End of Lower Pliensbachian

e1158 

geochronologic boundary
, era boundary
, Concept

experimental

End of Middle Toarcian

e1162 

geochronologic boundary
, Concept
, era boundary

experimental

End of Middle Berriasian

e1197 

era boundary
, Concept
, geochronologic boundary

experimental

End of Upper Lutetian

e1258 

geochronologic boundary
, Concept
, era boundary

experimental

End of Lower Bartonian

e1260 

Concept
, geochronologic boundary
, era boundary

experimental

End of Bavelian

e1297 

geochronologic boundary
, era boundary
, Concept

experimental

End of Holsteinian

e1309 

geochronologic boundary
, era boundary
, Concept

experimental

End of Eemian

e1317 

geochronologic boundary
, era boundary
, Concept

experimental

End of Early Weichselian

e1319 

Concept
, geochronologic boundary
, era boundary

experimental

End of Middle Weichselian

e1320 

Concept
, geochronologic boundary
, era boundary

experimental

End of Interpleniglacial

e1322 

geochronologic boundary
, Concept
, era boundary

experimental

End of Upper Pleniglacial

e1324 

Concept
, geochronologic boundary
, era boundary

experimental

End of Icartian

e2002 

Concept
, geochronologic boundary
, era boundary

experimental

End of Paleoproterozoic

e2003 

Concept
, geochronologic boundary
, era boundary

experimental

End of Sturtian

e2007 

Concept
, geochronologic boundary
, era boundary

experimental

End of Acadian

e2023 

era boundary
, geochronologic boundary
, Concept

experimental

End of Devillian

e2024 

era boundary
, Concept
, geochronologic boundary

experimental

End of Skiddavian

e2033 

Concept
, geochronologic boundary
, era boundary

experimental

End of Molinacian

e2055 

era boundary
, Concept
, geochronologic boundary

experimental

End of Livian

e2056 

geochronologic boundary
, Concept
, era boundary

experimental

End of Arundian

e2057 

era boundary
, Concept
, geochronologic boundary

experimental

End of Holkerian

e2058 

geochronologic boundary
, Concept
, era boundary

experimental

End of Upper Namurian

e2066 

Concept
, era boundary
, geochronologic boundary

experimental

End of Carixian

e2119 

era boundary
, Concept
, geochronologic boundary

experimental

End of Neuzivian

e2123 

Concept
, geochronologic boundary
, era boundary

experimental

End of Villersian

e2124 

Concept
, era boundary
, geochronologic boundary

experimental

End of Lusitanian

e2125 

geochronologic boundary
, era boundary
, Concept

experimental

End of Sequanian

e2129 

geochronologic boundary
, era boundary
, Concept

experimental

End of Pterocerian

e2130 

Concept
, era boundary
, geochronologic boundary

experimental

End of Volgian

e2136 

geochronologic boundary
, era boundary
, Concept

experimental

End of Upper Volgian

e2139 

Concept
, geochronologic boundary
, era boundary

experimental

End of Portlandian

e2140 

geochronologic boundary
, Concept
, era boundary

experimental

End of Upper Portlandian

e2142 

era boundary
, geochronologic boundary
, Concept

experimental

End of Urgonian (Provence)

e2146 

geochronologic boundary
, Concept
, era boundary

experimental

End of Urgonian (Vercors)

e2147 

era boundary
, Concept
, geochronologic boundary

experimental

End of Urgonian (Jura)

e2148 

geochronologic boundary
, era boundary
, Concept

experimental

End of Bedoulian

e2150 

geochronologic boundary
, era boundary
, Concept

experimental

End of Rognacian

e2166 

geochronologic boundary
, era boundary
, Concept

experimental

End of Ilerdian

e2175 

Concept
, era boundary
, geochronologic boundary

experimental

End of Biarritzian

e2179 

era boundary
, Concept
, geochronologic boundary

experimental

End of Assian

e2180 

geochronologic boundary
, Concept
, era boundary

experimental

End of Auversian

e2181 

geochronologic boundary
, era boundary
, Concept

experimental

End of Lattorfian

e2184 

era boundary
, geochronologic boundary
, Concept

experimental

End of Tongrian

e2185 

Concept
, era boundary
, geochronologic boundary

experimental

End of Upper Tongrian

e2187 

Concept
, era boundary
, geochronologic boundary

experimental

End of Sannoisian

e2189 

geochronologic boundary
, era boundary
, Concept

experimental

End of Astaracian

e2195 

geochronologic boundary
, Concept
, era boundary

experimental

End of Savignean

e2196 

era boundary
, geochronologic boundary
, Concept

experimental

End of Villafranchian

e2216 

era boundary
, Concept
, geochronologic boundary

experimental

End of Upper Villafranchian

e2218 

geochronologic boundary
, Concept
, era boundary

experimental

End of Biber/Donau Interglacial

e2221 

Concept
, geochronologic boundary
, era boundary

experimental

End of Tyrrhenian

e2235 

era boundary
, geochronologic boundary
, Concept

experimental

End of Riss/Wurm interglacial

e2236 

era boundary
, geochronologic boundary
, Concept

experimental

End of Oldest Dryas

e2242 

geochronologic boundary
, era boundary
, Concept

experimental

End of Smithian

e3004 

geochronologic boundary
, era boundary
, Concept

experimental

End of Aegean

e3006 

era boundary
, Concept
, geochronologic boundary

experimental

End of Middle Anisian

e3007 

geochronologic boundary
, Concept
, era boundary

experimental

End of Pelsonian

e3009 

geochronologic boundary
, Concept
, era boundary

experimental

End of Fassanian

e3011 

geochronologic boundary
, Concept
, era boundary

experimental

End of Julian

e3013 

Concept
, geochronologic boundary
, era boundary

experimental

End of Lacian

e3015 

geochronologic boundary
, Concept
, era boundary

experimental

End of Alaunian

e3016 

Concept
, geochronologic boundary
, era boundary

experimental

End of Toyonian

e3028 

Concept
, era boundary
, geochronologic boundary

experimental

End of Botomian

e3029 

era boundary
, Concept
, geochronologic boundary

experimental

End of Middle Norian

e3032 

Concept
, geochronologic boundary
, era boundary

experimental
