Table T11. Geomagnetic polarity timescale used during Expedition 346.
|
Geological age |
Base age (Ma) |
Chron | Subchron |
Age top (Ma) |
Age base (Ma) |
Duration (m.y.) |
Remarks |
|---|---|---|---|---|---|---|---|
| Neogene | |||||||
| Holocene | 11.5 ka | ||||||
| Pleistocene | C1 | C1n (Brunhes) | 0 | 0.781 | 0.781 | Base of middle Pleistocene (Ionian) is base of Brunhes Chron | |
| Late (Tarantian) | 0.126 | C1r.1r (Matuyama) | 0.781 | 0.988 | 0.207 | ||
| Middle (Ionian) | 0.781 | C1r.1n (Jaramillo) | 0.988 | 1.072 | 0.084 | ||
| C1r.2r | 1.072 | 1.173 | 0.101 | ||||
| C1r.2n (Cobb Mountain) | 1.173 | 1.185 | 0.012 | Cobb Mountain cryptochron is within early part of Matuyama (C1r) Chron | |||
| C1r.3r | 1.185 | 1.778 | 0.593 | ||||
| Early (Calabrian) | 1.806 | C2 | C2n (Olduvai) | 1.778 | 1.945 | 0.167 | Base of Calabrian is in lower part of Olduvai Chron |
| C2r.1r | 1.945 | 2.128 | 0.183 | ||||
| C2r.1n (Reunion) | 2.128 | 2.148 | 0.020 | ||||
| C2r.2r (Matuyama) | 2.148 | 2.581 | 0.433 | Base of Pleistocene is near base of Matuyama Chron | |||
| (Gelasian) | 2.588 | ||||||
| Pliocene | C2A | C2An.1n (Gauss) | 2.581 | 3.032 | 0.451 | “Gauss Normal Chron” (C2An) contains two reversed intervals: Kaena (2An.1r) and Mammoth (2An.2r) | |
| C2An.1r (Kaena) | 3.032 | 3.116 | 0.084 | ||||
| C2An.2n | 3.116 | 3.207 | 0.091 | ||||
| C2An.2r (Mammoth) | 3.207 | 3.330 | 0.123 | ||||
| Late (Piacenzian) | 3.600 | C2An.3n (Gauss) | 3.330 | 3.596 | 0.266 | Base of Piacenzian is base of Chron C2An.3n | |
| C2Ar (Gilbert) | 3.596 | 4.187 | 0.591 | “Gilbert Reversed Chron” spans Chrons C2Ar through C3r | |||
| C3 | C3n.1n (Cochiti) | 4.187 | 4.300 | 0.113 | |||
| C3n.1r | 4.300 | 4.493 | 0.193 | ||||
| C3n.2n (Nunivak) | 4.493 | 4.631 | 0.138 | ||||
| C3n.2r | 4.631 | 4.799 | 0.168 | ||||
| C3n.3n (Sidufjall) | 4.799 | 4.896 | 0.097 | ||||
| C3n.3r | 4.896 | 4.997 | 0.101 | ||||
| Early (Zanclean) | 5.332 | C3n.4n (Thvera) | 4.997 | 5.235 | 0.238 | Base of Miocene is in uppermost Chron C3r | |
| Miocene | C3r (Gilbert) | 5.235 | 6.033 | 0.798 | |||
| C3A | C3An.1n | 6.033 | 6.252 | 0.219 | |||
| C3An.1r | 6.252 | 6.436 | 0.184 | ||||
| C3An.2n | 6.436 | 6.733 | 0.297 | ||||
| C3Ar | 6.733 | 7.140 | 0.407 | ||||
| C3B | C3Bn | 7.140 | 7.212 | 0.072 | |||
| Late (Messinian) | 7.246 | C3Br.1r | 7.212 | 7.251 | 0.039 | Base of Messinian is in lowermost Chron C3Br.1r | |
| C3Br.1n | 7.251 | 7.285 | 0.034 | ||||
| C3Br.2r | 7.285 | 7.454 | 0.169 | ||||
| C3Br.2n | 7.454 | 7.489 | 0.035 | ||||
| C3Br.3r | 7.489 | 7.528 | 0.039 | ||||
| C4 | C4n.1n | 7.528 | 7.642 | 0.114 | |||
| C4n.1r | 7.642 | 7.695 | 0.053 | ||||
| C4n.2n | 7.695 | 8.108 | 0.413 |
Previous | Close | Next | Top of page