New Zealand geologic time scale

While also using the international geologic time scale, many nations - especially those with isolated and therefore non-standard prehistories - use their own system of dividing geologic time into epochs and faunal stages.

In New Zealand, these epochs and stages use local place names (mainly Maori in origin) back to the Permian. Prior to this time, they largely use the same terms as used in the Australian geologic time scale, and are not divided into epochs. In practice, these early terms are rarely used, as most New Zealand geology is of more recent origin. In all cases, New Zealand uses the same periods as used internationally; it is only the subdivisions of these periods that have been renamed. Very few epochs and stages cross international period boundaries. Of those that do, almost all are within the Cenozoic Era.

Though the New Zealand geologic time scale has not been formally adopted, it has become widely used by New Zealand earth scientists, geologists and palaeontologists since its proposal by J. S. Crampton in 1995.

A standard abbreviation is also used for these epochs and stages, mostly in the form Xx where the first letter is the initial letter of the epoch and the second (lower-case) letter is the initial letter of the stage. These are listed alongside the stage names in the list below.

Currently, we are in the Haweran stage of the Wanganui epoch. The Haweran, which started some 340,000 years ago, is named after the North Island town of Hawera.

List of New Zealand geologic time epochs and stages

Times given indicate the start of the respective stages and epochs. Several of these stages are further divided into upper and lower or upper, middle, and lower, although this has not been noted below unless unique names have been given to these sub-stages. As with the international geologic scale, these epochs and stages are largely named for locales where rock dating from these time periods is in evidence. Where known, these places are also linked in the list below.

Cenozoic Era

Name	Abbreviation	Start date (Ma)	International equivalent	Named after
Wanganui epoch	W		Pliocene, Pleistocene and Holocene	Wanganui
Haweran stage	Wq	0.34		Hawera
Castlecliffian stage	Wc	1.63		Castlecliff
Nukumaruan stage	Wn	2.40		Nukumaru
Mangapanian stage	Wm	3.00		Mangapani
Waipipian stage	Wp	3.60		Waipipi
Opoitian stage	Wo	5.33		Opoiti
Taranaki epoch	T		Upper Miocene	Taranaki
Kapitean stage	Tk	7.2		Kapiti Island
Tongaporutuan stage	Tt	11.01		Tongaporutu
Southland epoch	S		Middle Miocene	Southland
Waiauan stage	Sw	12.98		Waiau River
Lillburnian stage	Sl	15.1		Lillburn Valley
Clifdenian stage	Sc	15.9		Clifden
Pareora epoch	P		Lower Miocene	Pareora
Altonian stage	Pl	18.7		Alton
Otaian stage	Po	21.7		Otaio
Landon epoch	L		Oligocene to Lower Miocene
Waitakian stage	Lw	25.2		Waitaki River
Duntroonian stage	Ld	27.3		Duntroon
Whaingaroan stage	Lwh	34.5		Whaingaroa
Arnold epoch	A		Middle to Upper Eocene	Arnold River
Runangan stage	Ar	36.0		Runanga
Kaiatan stage	Ak	38.4		Kaiata
Bortonian stage	Ab	42.77		Bortons
Dannevirke epoch	D		Lower Palaeocene to Middle Eocene	Dannevirke
Porangan stage	Dp	45.3		Poranga
Heretaungan stage	Dh	49.3		Heretaunga Plains
Mangaorapan stage	Dm	53.3		Mangaorapa
Waipawan stage	Dw	55.8		Waipawa
Teurian stage	Dt	65.5		Te Uri

Mesozoic Era

Cretaceous Period

Name	Abbreviation	Start date (Ma)	Named after
Mata epoch	M
Haumurian stage	Mh	84.0	Haumuri Bluff
Piripauan stage	Mp	86.5	Piripaua
Raukumara epoch	R		Raukumara Range
Teratan stage	Rt	89.1
Mangaotanean stage	Rm	92.1	Mangaotane
Arowhanan stage	Ra	95.2	Arowhana
Clarence epoch	C		Clarence River
Ngaterian stage	Cn	100.2
Motuan stage	Cm	103.3	Motu River
Urutawan stage	Cu	108.4	Urutawa, a hill north of Matawai
Taitai epoch	U		Taitai, a hill near Ruatoria
Korangan stage	Uk	117.5	Koranga
Undifferentiated Taitai		145.5

Jurassic Period

Name	Abbreviation	Start date (Ma)	Named after
Oteke epoch	O
Puaroan stage	Op	148.5
Kawhia epoch	K		Kawhia Harbour
Ohauan stage	Ko	153.5
Heterian stage	Kh	157.5
Temaikan stage	Kt	175.6
Herangi epoch	H
Ururoan stage	Hu	188.0
Aratauran stage	Ha	199.6

Triassic Period

Name	Abbreviation	Start date (Ma)	Named after
Balfour epoch	B		Balfour
Otapirian stage	Bo	204.6
Warepan stage	Bw	212.0	Warepa
Otamitan stage	Bm	217.0
Oretian stage	Br	227.5	Oreti River
Gore epoch	G		Gore
Kaihikuan stage	Gk	238.5
Etalian stage	Ge	244.5
Malakovian stage	Gm	245.5
Nelsonian stage	Gn	250.4	Nelson
Makarewan stage (see Permian Period, below)

Palaeozoic Era

Permian Period

Name	Abbreviation	Start date (Ma)	Named after
D'Urville epoch	YD		D'Urville Island
Makarewan stage	YDm	253.8	Makarewa River
Waiitian stage	YDw	?	Wai-iti River
Puruhauan stage	YDp	260.4
Aparima epoch	YA		Aparima River
Flettian stage	YAf	266.5
Barettian stage	YAr	273.0
Mangapirian stage	YAm	280.0
Telfordian stage	YAt	283.0
Pre-Telfordian epoch (not subdivided into stages)	Ypt	299.0

Carboniferous Period

Name	Abbreviation	Start date (Ma)
Carboniferous Period (not subdivided)	F	359.2

Devonian Period

Stages prior to the beginning of the Carboniferous Period use either international (Devonian/Silurian) or Australian (Ordovician/Cambrian) geologic stage names; very little New Zealand rock is known from these geologic periods.

Name	Abbreviation	Start date (Ma)
Upper Devonian epoch	JU
Famennian stage		374.5
Frasnian stage		385.3
Middle Devonian epoch	JM
Givetian stage		391.8
Eifelian stage		397.5
Lower Devonian epoch	JL
Emsian stage	Jem	407.0
Pragian stage	Jpr	411.2
Lochkovian stage	Jlo	417.2

Silurian Period

Name	Abbreviation	Start date (Ma)
Pridoli epoch (not subdivided into stages)	Epr	419.7
Ludlow epoch	Elu
Ludfordian stage		422.0
Gorstian stage		423.5
Wenlock epoch	Ewe
Homerian stage		426.2
Sheinwoodian stage		428.4
Llandovery epoch	Ela
Telychian stage		435.9
Aeronian stage		439.7
Rhuddanian stage		443.2

Ordovician Period

Name	Abbreviation	Start date (Ma)
Upper Ordovician epoch
Bolindian stage	Vbo	449.7
Eastonian stage	Vea	456.1
Gisbornian stage	Vgi	460.5
Middle Ordovician epoch
Darriwilian stage	Vda	468.1
Yapeenian stage	Vya	468.9
Castlemainian stage	Vca	472.0
Lower Ordovician epoch
Chewtonian stage	Vch	473.9
Bendigonian stage	Vbe	476.8
Lancefieldian stage	Vla	488.7
Pre-Lancefieldian stage	Vpl	490.0

Cambrian Period

Name	Abbreviation	Start date (Ma)
Datsonian stage	Xda	491.5
Payntonian stage	Xpa	494.0
Iverian stage	Xiv	498.5
Idamean stage	Xid	501.0
Mindyallan stage	Xmi	503.0
Boomerangian stage	Xbo	504.0
Undillan stage	Xun	505.0
Floran stage	Xfl	507.0
Ordian/Templetonian stage	Xor	513.0
Early Cambrian (not subdivided)	XL	542.0

Proterozoic and Archaean Aeons

Name	Abbreviation	Start date (Ma)
(Not subdivided)	Z

Footnotes to time scale

^ This stage is sometimes further divided into Mangaoran (lower) and Waikatoan (upper).
^ This stage is sometimes further divided into Kiriteherean (lower) and Marokopan (upper).
^ Until recently, the Flettian and Barettian stages were together known as the Braxtonian stage.

References

Bishop, D.G., and Turnbull, I.M. (compilers) (1996). Geology of the Dunedin Area. Lower Hutt, NZ: Institute of Geological & Nuclear Sciences. ISBN 0-478-09521-X.
Hollis, C.J., Beu, A.G., Crampton, J.S., Crundwell, M.P., Morgans, H.E.G., Raine, J.I., Jones, C.M., Boyes, A.F. (2010). Calibration of the New Zealand Cretaceous - Cenozoic Timescale to GTS2004, GNS Science Report, 2010/43, 20p.

External links

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