GSA GEOLOGIC TIME SCALE v. 5.0
C5A
5B C5B
5C C5C
5D C5D
20
5E C5E
6 C6
SERRAVALLIAN
15.97
12
13
18
19
C18
20
C20
45
21
50
C21
22 C22
23
130
140
150
RUPELIAN
37.8
170
BARTONIAN
41.2
LUTETIAN
180
190
47.8
YPRESIAN
60
27
C27
28 C28
65
29
C29
30 C30
PALEOCENE
C26
~113
320
APTIAN
EARLY
BARREMIAN
HAUTERIVIAN
~125
340
~129.4
~132.9
~139.8
HIST
CHRON.
TITHONIAN
M22
LATE
MIDDLE
KIMMERIDGIAN
OXFORDIAN
CALLOVIAN
BATHONIAN
BAJOCIAN
AALENIAN
~152.1
380
~157.3
~163.5
~166.1
~168.3
~170.3
~174.1
400
420
440
~190.8
SINEMURIAN
HETTANGIAN
~199.3
~201.3
460
220
THANETIAN
59.2
230
SELANDIAN
61.6
240
DANIAN
66.0
250
~208.5
480
LATE
500
CARNIAN
ANISIAN
EARLY
OLENEKIAN
INDUAN
EARLY
BASHKIRIAN
LATE
SERPUKHOVIAN
MIDDLE
VISEAN
EARLY
TOURNAISIAN
LATE
~237
520
~242
247.2
251.2
251.90
EON
MIDDLE
259.1
265.1
268.8
272.95
~283.5
1250
315.2
323.2
1500
330.9
346.7
NEOPROTEROZOIC
750
1000
290.1
295.0
298.9
303.7
307.0
1750
358.9
~372.2
GIVETIAN
EIFELIAN
ERA
~382.7
~387.7
~393.3
2000
PRIDOLI
LUDLOW
WENLOCK
LLANDOVERY
LATE
MIDDLE
EARLY
Epoch 3
Epoch 2
TERRENEUVIAN
LUDFORDIAN
GORSTIAN
HOMERIAN
SHEINWOODIAN
TELYCHIAN
AERONIAN
RHUDDANIAN
HIRNANTIAN
KATIAN
SANDBIAN
DARRIWILIAN
DAPINGIAN
FLOIAN
TREMADOCIAN
AGE 10
JIANGSHANIAN
PAIBIAN
GUZHANGIAN
DRUMIAN
AGE 5
AGE 4
AGE 3
AGE 2
~407.6
~410.8
~419.2
~423.0
~425.6
~427.4
~430.5
~433.4
~438.5
~440.8
~443.8
~445.2
~453.0
~458.4
~467.3
~470.0
635
720
1000
1200
MESOPROTEROZOIC
ECTASIAN
1400
CALYMMIAN
1600
STATHERIAN
1800
OROSIRIAN
PALEOPROTEROZOIC
2050
RHYACIAN
2300
SIDERIAN
2500
2500
NEOARCHEAN
2750
2800
3000
3250
3500
MESOARCHEAN
3200
PALEOARCHEAN
3600
3750
EOARCHEAN
~521
~529
FORTUNIAN
540
541
TONIAN
2250
~477.7
~485.4
~489.5
~494
~497
~500.5
~504.5
~509
~514
CRYOGENIAN
BDY.
AGES
(Ma)
STENIAN
EMSIAN
PRAGIAN
PERIOD
EDIACARAN
FRASNIAN
FURONGIAN
~227
MIDDLE
MOSCOVIAN
AGE
(Ma)
251.90
254.14
FAMENNIAN
NORIAN
LADINIAN
SAKMARIAN
ASSELIAN
GZHELIAN
KASIMOVIAN
LOCHKOVIAN
~182.7
PLIENSBACHIAN
LATE
PICKS
(Ma)
ARTINSKIAN
MIDDLE
EARLY
TOARCIAN
EARLY
Cisuralian
360
~145.0
200
210
56.0
C25
300
RHAETIAN
C24
25
280
93.9
100.5
BERRIASIAN
160
PRIABONIAN
83.6
86.3
89.8
ALBIAN
VALANGINIAN
M25
33.9
C23
26
CENOMANIAN
M12
M14
M16
M18
M20
M29
24
55
M0r
M1
M3
M5
TURONIAN
M10
27.82
C17
C19
120
CHATTIAN
C13
15 C15
16 C16
17
40
C12
EOCENE
35
C11
PALEOGENE
30
OLIGOCENE
TERTIARY
10 C10
11
110
BURDIGALIAN
23.03
7 C7
7A C7A
8 C8
34 C34
LANGHIAN
6C C6C
C9
100
AQUITANIAN
6B C6B
9
13.82
20.44
6A C6A
25
90
11.63
SANTONIAN
CONIACIAN
PERMIAN
TORTONIAN
LATE
Guadalupian
CHANGHSINGIAN
WUCHIAPINGIAN
CAPITANIAN
WORDIAN
ROADIAN
KUNGURIAN
PRECAMBRIAN
PROTEROZOIC
15
C5
260
CAMPANIAN
PENNSYLVANIAN
5A
C4A
C33
80
7.246
Lopingian
72.1
33
AGE
66.0
MISSISSIPPIAN
5
MIOCENE
10
NEOGENE
4A
C4
5.333
MAASTRICHTIAN
32 C32
CARBONIFEROUS
MESSINIAN
3A C3A
4
ZANCLEAN
30 C30
31 C31
AGE
PERIOD EPOCH
(Ma)
DEVONIAN
PLIOCENE
C3
70
PICKS
(Ma)
ORDOVICIAN SILURIAN
3
0.012
1.8
2.58
3.600
AGE
PALEOZOIC
CAMBRIAN
5
CALABRIAN
GELASIAN
PIACENZIAN
PERIOD EPOCH
CRETACEOUS
2A C2A
AGE
(Ma)
JURASSIC
HOLOCENE
QUATERNARY PLEISTOCENE*
PICKS
(Ma)
TRIASSIC
C1
C2
AGE
RAPID POLARITY CHANGES
1
2
EPOCH
ANOM.
PERIOD
CHRON.
HIST.
ANOM.
AGE
(Ma)
MAGNETIC
POLARITY
ARCHEAN
MESOZOIC
CENOZOIC
MAGNETIC
POLARITY
541.0
4000
4000
HADEAN
Walker, J.D., Geissman, J.W., Bowring, S.A., and Babcock, L.E., compilers, 2018, Geologic Time Scale v. 5.0: Geological Society of America, https://doi.org/10.1130/2018.CTS005R3C. ©2018 The Geological Society of America
*The Pleistocene is divided into four ages, but only two are shown here. What is shown as Calabrian is actually three ages—Calabrian from 1.80 to 0.781 Ma, Middle from 0.781 to 0.126 Ma, and Late from 0.126 to 0.0117 Ma.
The Cenozoic, Mesozoic, and Paleozoic are the Eras of the Phanerozoic Eon. Names of units and age boundaries usually follow the Gradstein et al. (2012), Cohen et al. (2012) , and Cohen et al. (2013, updated) compilations. Numerical age estimates
and picks of boundaries usually follow the Cohen et al. (2013, updated) compilation. The numbered epochs and ages of the Cambrian are provisional. A “~” before a numerical age estimate typically indicates an associated error of ±0.4 to over 1.6 Ma.
REFERENCES CITED
Cohen, K.M., Finney, S., and Gibbard, P.L., 2012, International Chronostratigraphic Chart: International Commission on Stratigraphy, www.stratigraphy.org (accessed May 2012). (Chart reproduced for the 34th International Geological Congress, Brisbane,
Australia, 5–10 August 2012.)
Cohen, K.M., Finney, S.C., Gibbard, P.L., and Fan, J.-X., 2013, The ICS International Chronostratigraphic Chart: Episodes v. 36, no. 3, p. 199–204 (updated 2017, v. 2, http://www.stratigraphy.org/index.php/ics-chart-timescale; accessed May 2018).
Gradstein, F.M, Ogg, J.G., Schmitz, M.D., et al., 2012, The Geologic Time Scale 2012: Boston, USA, Elsevier, https://doi.org/10.1016/B978-0-444-59425-9.00004-4.
Previous versions of the time scale and previously published papers about the time scale and its evolution are posted to http://www.geosociety.org/timescale.