List of Global Boundary Stratotype Sections and Points

This is a list of Global Boundary Stratotype Sections and Points. Since 1977, Global Boundary Stratotype Sections and Points (abbreviated GSSPs) are internationally agreed upon reference points on stratigraphic sections of rock which define the lower boundaries of stages on the geologic time scale. They are selected by the International Commission on Stratigraphy based on multiple factors, but their accessibility and the degree to which they are representative of the same boundary on sections worldwide are among the most important.

Since GSSPs require well-preserved sections of rock without interruptions in sedimentation, and since most are defined by different stages of animal life, defining them becomes progressively more difficult as one goes further back in time.

Organization of this list

This list is divided first into the geologic eras of the Phanerozoic (the Cenozoic, the Mesozoic, and the Paleozoic) and then into the geologic periods of each era. Each period is marked below the era bar on top of its subdivided epochs and stages. Each stage is assigned an age in mya, an acronym for million years ago, which is the age at which it began. Most of these ages are derived from astronomical cycles in sediments, magnetic data, biostratigraphic data, and radiometric dating methods. The GSSP assigned to each stage is that stage's lower boundary and oldest point.

Ages are given in "million year ago" (mya). They are obtained with different radiometric dating methods depending on the type of rock and its age. Ages that have a tilde (~) prefix are approximate ages for GSSPs that have not been defined or not been accurately dated.

The Status column has a "golden spike" for every GSSP which has been formally agreed by the ICS. Those without have only candidate sections which have not yet been formally ratified. The clock stands for times that are currently defined only by an age.

The "Defining markers" column lists the evidence in the rock used to define the boundary. (Ideally, these are applicable in rock sections worldwide.) Most of the boundaries rely on the fossil record (biologic), paleomagnetic data (magnetic), and/or climate data determined by carbon and oxygen isotopes.

List

Cenozoic

Quaternary

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Holocene		0.0117		NGRIP2 ice core, Greenland	Climatic: End of the Younger Dryas stadial.	75°06′00″N 42°19′12″W / 75.1000°N 42.3200°W	[1]
Pleistocene
	Tarantian	0.126		Amsterdam-Terminal borehole, Netherlands	Climatic: Beginning of the Eemian interglacial stage.	52°22′45″N 4°54′52″E / 52.3792°N 4.9144°E	[2]
	Ionian	0.781		Candidate sections: Montalbano Jorica or Valle di Manche, Italy Chiba, Japan	Magnetic: Brunhes-Matuyama magnetic reversal.	-	[3]
	Calabrian	1.80		Vrica Section, Calabria, Italy	Magnetic: Approximately 15 ka after the end of magnetic polarity chronozone C2n (Olduvai). Biologic: Immediately above extinction Discoaster brouweri (Haptophyte). Sedimentologic: Boundary between a sapropelic bed and marine claystones.	39°02′19″N 17°08′05″E / 39.0385°N 17.1348°E	[4]
	Gelasian	2.58		Monte San Nicola Section, Gela, Sicily, Italy	Magnetic: Base of magnetic polarity chronozone C2r (Matuyama). Biologic: Extinction of Discoaster pentaradiatus and Discoaster surculus (Haptophyte).	37°08′49″N 14°12′13″E / 37.1469°N 14.2035°E	[5]

Neogene

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Pliocene
	Piacenzian	3.600		Punta Piccola Section, Porto Empedocle, Sicily, Italy	Magnetic: Base of magnetic polarity chronozone C2An (Gauss). Biologic: Extinction of Globorotalia margaritae and Pulleniatina primalis (Planktonic foraminifera).	37°17′20″N 13°29′36″E / 37.2889°N 13.4933°E	[6]
	Zanclean	5.333		Heraclea Minoa section Heraclea Minoa, Cattolica Eraclea, Sicily, Italy	Magnetic: Top of magnetic polarity chronozone C3r. Biologic: First appearance of Ceratolithus acutus and near extinction of Triquetrorhabdulus rugosus (Haptophyte).	37°23′30″N 13°16′50″E / 37.3917°N 13.2806°E	[7]
Miocene
	Messinian	7.246		Oued Akrech section, Rabat, Morocco	Magnetic: Within magnetic polarity chronozone C3Br.1r. Biologic: First regular occurrence of the Globorotalia miotumida (Planktonic foraminifera). Biologic: First appearance of Amaurolithus delicatus (Haptophyte).	33°56′13″N 6°48′45″W / 33.9369°N 6.8125°W	[8]
	Tortonian	11.63		Monte dei Corvi Beach section, Ancona, Italy	Magnetic: Within normal-polarity subchron C5r.2n Biologic: Last Common Occurrence of the Discoaster kugleri (Haptophyte). Biologic: Last Common Occurrence of the Globigerinoides subquadratus (Planktonic foraminifera). Climatic: Oxygen isotope event Mi-5.	43°35′12″N 13°34′10″E / 43.5867°N 13.5694°E	[9]
	Serravallian	13.82		Ras il Pellegrin section, Fomm ir-Riħ Bay, Malta	Magnetic: Within magnetic polarity chronozone C5ABr. Biologic: Below first appearance of Sphenolithus heteromorphus (Haptophyte) Climatic: Mi3b isotopic event (Global cooling episode).	35°54′50″N 14°20′10″E / 35.9139°N 14.3361°E	[10]
	Langhian	15.97		Candidate sections: La Vedova, Italy St. Peter's Pool, Malta Astronomically tuned Ocean Drilling Program-core	Magnetic: Top of magnetic polarity chronozone C5Cn.1n. Biologic: Near first appearance of Praeorbulina glomerosa (Planktonic foraminifera).	-	[3]
	Burdigalian	20.44		Candidate sections: Astronomically tuned ODP core (e.g. Ceara Rise, Leg 154)	Near FAD of Globigerinoides altiaperturus (planktonic foraminifer) or near top of magnetic polarity chronozone C6An	-	[3]
	Aquitanian	23.03		Lemme-Carrosio Section, Carrosio, Italy	Magnetic: Base of magnetic polarity chronozone C6Cn.2n. Biologic: Near first appearance of Paragloborotalia kugleri (Planktonic foraminifera).	44°39′32″N 8°50′11″E / 44.6589°N 8.8364°E	[11]

Paleogene

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Oligocene
	Chattian	28.1		Candidate section: Monte Cagnero, Central Apennines, Italy	Potentially extinction of planktonic foraminifer Chiloguembelina (Base of Foram Zone P21b); or an isotopic/climatic event	-	-
	Rupelian	33.9		Massignano quarry section, Massignano, Ancona, Italy	Biologic: Extinction of Hantkenina and Cribrohantkenina (Planktonic foraminifera).	43°31′58″N 13°36′04″E / 43.5328°N 13.6011°E	[12]
Eocene
	Priabonian	37.8		Alano section, Piave river, Venetian Prealps, Belluno, Italy	Biologic: Near first appearance of Chiasmolithus oamaruensis (Haptophyte).	-	-
	Bartonian	41.2		Contessa highway section Gubbio, Central Apennines, Italy	Biologic: Near Extinction of Reticulofenestra reticulata (Haptophyte)	-	-
	Lutetian	47.8		Gorrondatxe sea-cliff section, Western Pyrenees, Basque Country, Spain	Biologic: First appearance of Hantkenina (Planktonic foraminifera).	43°22′47″N 3°00′51″W / 43.3796°N 3.0143°W	[13]
	Ypresian	56.0		Dababiya section, Luxor, Egypt	Climatic: Base of negative Carbon Isotope Excursion (CIE).	25°30′00″N 32°31′52″E / 25.5000°N 32.5311°E	[14][15]
Paleocene
	Thanetian	59.2		Zumaia Section, Basque Country, Spain	Magnetic: Base of magnetic polarity chronozone C26n.	43°17′59″N 2°15′39″W / 43.2996°N 2.2609°W	[16]
	Selandian	61.6		Zumaia Section, Basque Country, Spain	Chemical: Onset of sea-level drop and carbon isotope shift. Magnetic: 30 precession cycles after the top of magnetic polarity Chron 27n	43°17′57″N 2°15′40″W / 43.2992°N 2.2610°W	[16]
	Danian	66.0		El Kef Section, El Kef, Tunisia	Iridium enriched layer associated with a major meteorite impact and subsequent extinction event.	36°09′13″N 8°38′55″E / 36.1537°N 8.6486°E	[17]

Mesozoic

Cretaceous

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Upper
	Maastrichtian	72.1 ± 0.2		Grande Carrière quarry, Landes, France	Biologic: 12 biostratigraphic criteria Biologic: First appearance of Pachydiscus neubergicus (Ammonite) is just above the boundary.	43°40′46″N 1°06′48″W / 43.6795°N 1.1133°W	[18]
	Campanian	83.6 ± 0.2		Candidate sections: Seaford Head, Sussex, England Waxahachie dam spillway, Texas, USA	Biologic: Extinction of Marsupites testudinarius (Crinoid).	-	[3]
	Santonian	86.3 ± 0.5		Olazagutia, Spain	Biologic: First appearance of Cladoceramus undulatoplicatus (Inoceramid bivalve).	-	[3]
	Coniacian	89.8 ± 0.3		Candidate sections: Słupia Nadbrzeżna, Poland Pueblo, Colorado, USA Salzgitter-Salder quarry, Germany	Biologic: First appearance of Cremnoceramus rotundatus (Inoceramid bivalve).	-	[3]
	Turonian	93.9		Rock Canyon, Colorado, USA	Biologic: First appearance of Watinoceras devonense (Ammonite).	38°16′56″N 104°43′39″W / 38.2822°N 104.7275°W	[19]
	Cenomanian	100.5		Mont Risoux, Hautes-Alpes, France	Biologic: First appearance of Rotalipora globotruncanoides (Planktonic foraminifera)	44°23′33″N 5°30′43″E / 44.3925°N 5.5119°E	[20]
Lower
	Albian	~113.0		Candidate section: France	Candidates: Haptophyte FAD of Praediscosphaera columnata (= P. cretacea of some earlier studies) Carbon-isotope excursion (black-shale episode) Ammonite	-	-
	Aptian	~125.0		Candidate section: Gorgo a Cerbara, Piobbico, Central Apennines, Italy	Magnetic: Base of magnetic polarity chronozone M0r. Biologic: Near first appearance of Paradeshayesites oglanlensis (Ammonite).	-	-
	Barremian	~129.4		Candidate section: Río Argos, Caravaca de la Cruz, Murcia Province, Spain	Biologic: First appearance of Spitidiscus hugii or Spitidiscus vandeckii group (Ammonite).	-	-
	Hauterivian	~132.9		Candidate section: La Charce, Drôme, France	Biologic: First appearance of genus Acanthodiscus (Ammonite).	-	-
	Valanginian	~139.8		Candidates sections: Montbrun-les-Bains, Drôme, France Cañada Luenga, Betic Cordillera, Spain	Biologic: First appearance of Calpionellites darderi (Calpionellid). Biologic: First appearance of Thurmanniceras pertransiens (Ammonite).	-	-
	Berriasian	~145.0		-	Candidates: Magnetic—base of Chron M18r Base of Calpionellid zone B

Jurassic

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Upper
	Tithonian	152.1 ± 0.9		Candidate sections: Mt. Crussol, France Canjuers, France Fornazzo, Sicily	Magnetic: Base of magnetic polarity chronozone M22An. Biologic: Near first appearance of Hybonoticeras hybonotum (Ammonite). Biologic: First appearance of genus Gravesia (Ammonite).	-	-
	Kimmeridgian	157.3 ± 1.0		Candidate section: Flodigarry, Skye, Scotland	Biologic: First appearance of Pictonia baylei (Ammonite).	57°36′00″N 6°12′00″W / 57.6000°N 6.2000°W	-
	Oxfordian	163.5 ± 1.0		Candidate sections: Redcliff Point, Dorset, England Savouron, Provence, France	Biologic: Horizon of Cardioceras redcliffense (Ammonite).	-	-
Middle
	Callovian	166.1 ± 1.2		Candidate sections: Pfeffingen, Swabian Alb, Germany Russia	Biologic: First appearance of genus Kepplerites (Ammonite).	-	-
	Bathonian	168.3 ± 1.3		Ravin du Bès, Bas-Auran, Alpes de Haute, France	Biologic: First appearance of Gonolkites convergen (Ammonite).	43°57′38″N 6°18′55″E / 43.9606°N 6.3153°E	[21]
	Bajocian	170.3 ± 1.4		Cabo Mondego, Portugal	Biologic: First appearance of Hyperlioceras mundum, Hyperlioceras furcatum, Braunsina aspera, and Braunsina elegantula(Ammonite) Biologic: First appearance of genus Hyperlioceras (Ammonite).	40°11′57″N 8°54′15″W / 40.1992°N 8.9042°W	[22]
	Aalenian	174.1 ± 1.0		Fuentelsaz, Spain	Biologic: First appearance of Leioceras opalinum and Leioceras lineatum Biologic: First appearance of genus Leioceras (Ammonite).	41°10′15″N 1°50′00″W / 41.1708°N 1.8333°W	[23]
Lower
	Toarcian	182.7 ± 0.7		Peniche, Portugal	Biologic: Near first appearance of Eodactylites fauna (Ammonite). Biologic: Coincides with Protogrammoceras paltus horizon of NW-Europe.	-	-
	Pliensbachian	190.8 ± 1.0		Robin Hood's Bay, Yorkshire, England	Biologic: First appearance of Bifericeras donovani and genera Apoderoceras (Ammonite).	54°24′25″N 0°29′51″W / 54.4069°N 0.4975°W	[24]
	Sinemurian	199.3 ± 0.3		East Quantoxhead, West Somerset, England	Biologic: First appearance of the Vermiceras quantoxense, Vermiceras palmeri (Ammonite).	51°11′27″N 3°14′11″W / 51.1909°N 3.2364°W	[25]
	Hettangian	201.3 ± 0.2		Kuhjoch section, Karwendel mountains, Northern Calcareous Alps, Austria	Biologic: Near first appearance of smooth Psiloceras spela group (Ammonite).	47°29′02″N 11°31′50″E / 47.4839°N 11.5306°E

Triassic

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Upper
	Rhaetian	~208.5		Candidate sections: Steinbergkogel, Austria Turkey British Columbia	Biologic: Near first appearance of genus Cochloceras (Ammonite). Biologic: Near first appearance of Misikella sp. and Epigondolella mosheri (Conodont). Biologic: Near first appearance of Proparvicingula moniliformis.	-	-
	Norian	~227		Candidate sections: Black Bear Ridge, British Columbia Pizzo Mondello, Sicily	Base of Stikinoceras kerri ammonoid zone and near FAD of Metapolygnathus echinatus within the M. communisti conodont zones.	-	-
	Carnian	~237		Prati di Stuores, Dolomites, Italy	Biologic: First appearance of Daxatina canadensis (Ammonite). Biologic: Near first appearance of Metapolygnathus polygnathiformis (Conodont). Magnetic: Above magnetic zone S2n.	46°31′37″N 11°55′49″E / 46.5269°N 11.9303°E	[26]
Middle
	Ladinian	~242		Bagolino, Lombardian pre-Alps, Italy	Biologic: First appearance of Eoprotrachyceras curionii (Ammonite). Biologic: First appearance of Budurovignathus praehungaricus (Conodont).	45°49′09″N 10°28′16″E / 45.8193°N 10.4710°E	[27]
	Anisian	247.2		Candidate sections: Desli Caira, Dobrogea, Romania Guandao, Guizhou, China	Biologic: First appearance of Chiosella timorensis (Conodont). Magnetic: Base of magnetic zone MT1n.	45°04′27″N 28°48′08″E / 45.0742°N 28.8022°E
Lower
	Olenekian	251.2		Candidate sections: Mud (Muth) village, Spiti valley, India Chaohu, China	Biologic: First appearance of Neospathodus waageni (Conodont). Biologic: Near first appearance of genera Flemingites and Euflemingites (Ammonite).	31°57′55″N 78°01′29″E / 31.9654°N 78.0246°E
	Induan	252.17 ± 0.06		Meishan, Zhejiang, China	Biologic: First appearance of Hindeodus parvus (Conodont).	31°04′47″N 119°42′21″E / 31.0798°N 119.7058°E

Paleozoic

Permian

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Lopingian
	Changhsingian	254.14 ± 0.07		Zhejiang, China	Biologic: Near first appearance of Clarkina wangi (Conodont).	31°04′55″N 119°42′23″E / 31.0819°N 119.7064°E	[28]
	Wuchiapingian	259.8 ± 0.4		Penglaitan Section, Laibin, Guangxi, China	Biologic: First appearance of Clarkina postbitteri postbitteri (Conodont).	23°41′43″N 109°19′16″E / 23.6953°N 109.3211°E	[29]
Guadalupian
	Capitanian	265.1 ± 0.4		Nipple Hill, Guadalupe Mountains, Texas, U.S.A.	Biologic: First appearance of Jinogondolella postserrata (Conodont).	31°54′33″N 104°47′21″W / 31.9091°N 104.7892°W	[3]
	Wordian	268.8 ± 0.5		Guadalupe Pass, Guadalupe Mountains, Texas, U.S.A.	Biologic: First appearance of Jinogondolella aserrata (Conodont).	31°51′57″N 104°49′58″W / 31.8658°N 104.8328°W	[3]
	Roadian	272.3 ± 0.5		Stratotype Canyon, Guadalupe Mountains, Texas, U.S.A.	Biologic: First appearance of Jinogondolella nanginkensis (Conodont).	31°52′36″N 104°52′36″W / 31.8767°N 104.8768°W	[3]
Cisuralian
	Kungurian	283.5 ± 0.6		Candidate section: Ural mountains	Biologic: Near first appearance of Neostreptognathus pnevi (Conodont).	-	[3]
	Artinskian	290.1 ± 0.26		Candidate section: Ural mountains	Biologic: First appearance of Sweetognathus whitei (Conodont).	-	[3]
	Sakmarian	295.0 ± 0.18		Candidate section: Kondurovsky, Orenburg, Russia.	Biologic: Near first appearance of Sweetognathus merrelli (Conodont).	-	[3]
	Asselian	298.9 ± 0.15		Aidaralash, Ural Mountains, Kazakhstan	Biologic: First appearance of Streptognathodus isolatus within the morphotype Streptognathodus wabaunsensis chronocline (Conodont).	50°14′45″N 57°53′29″E / 50.2458°N 57.8914°E	[30]

Carboniferous

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Pennsylvanian
	Gzhelian	303.7 ± 0.1		Candidate sections: Ural mountains Nashui, Luodian County, Guizhou, China	Biologic: First appearance Idiognathodus simulator and close to first appearance of Shumardites	-	[3]
	Kasimovian	307.0 ± 0.1		Candidate sections: Ural mountains USA Nashui, Luodian County, Guizhou, China	Biologic: First appearance of Protriticites or 1 millions years older Montiparus montiparus	-	[3]
	Moscovian	315.2 ± 0.2		Candidate sections: Ural mountains Nashui, Luodian County, Guizhou, China	Biologic: First appearance of Idiognathoides postsulcatus or Declinognathodus donetzianus	-	[3]
	Bashkirian	323.2 ± 0.4		Arrow Canyon, Nevada, USA	Biologic: First appearance of Declinognathodus nodiliferus (Conodont).	36°44′00″N 114°46′40″W / 36.7333°N 114.7778°W	[31]
Mississippian
	Serpukhovian	330.9 ± 0.2		Candidate sections: Verkhnyaya Kardailovka, Ural mountains Nashui, Luodian County, Guizhou, China	Biologic: First appearance of Lochriea ziegleri	-	[3]
	Visean	346.7 ± 0.4		Pengchong Section, Guangxi, China	Biologic: First appearance of Eoparastaffella simplex	24°26′00″N 109°27′00″E / 24.4333°N 109.4500°E	[3]
	Tournaisian	358.9 ± 0.4		La Serre, Montagne Noire, France	Biologic: First appearance of Siphonodella sulcata (Conodont). In 2006 it was discovered that this GSSP has biostratigraphic problems.	43°33′20″N 3°21′26″E / 43.5555°N 3.3573°E	[32]

Devonian

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Upper
	Famennian	372.2 ± 1.6		Coumiac quarry, Montagne Noire, France	Biologic: Abundant occurrence of Palmatolepis triangularis (Conodont). Biologic: Upper Kellwasser Extinction of all Ancyrodella and Ozarkodina and most Palmatolepis, Polygnathus, and Ancyrognathus. Biologic: Coincides with the first appearance of Phoenixites frechi (Goniatite).	43°27′41″N 3°02′25″E / 43.4613°N 3.0403°E	[33]
	Frasnian	382.7 ± 1.6		Col du Puech de la Suque, Montagne Noire, France	Biologic: First appearance of Ancyrodella rotundiloba (Conodont).	43°30′12″N 3°05′12″E / 43.5032°N 3.0868°E	[34]
Middle
	Givetian	387.7 ± 0.8		Jebel Mech Irdane, Tafilalt, Morocco	Biologic: First appearance of Polygnathus hemiansatus (Conodont). Biologic: Just below first appearance of Maenioceras (Goniatite).	31°14′15″N 4°21′15″W / 31.2374°N 4.3541°W	[35]
	Eifelian	393.3 ± 1.2		Wetteldorf Richtschnitt section, Wetteldorf, Eifel, Germany	Biologic: First appearance of Polygnathus costatus partitus (Conodont).	50°08′59″N 6°28′18″E / 50.1496°N 6.4716°E	[36]
Lower
	Emsian	407.6 ± 2.6		Zinzil'ban Gorge, Uzbekistan	Biologic: First appearance of Polygnathus kitabicus (Conodont).	39°12′00″N 67°18′20″E / 39.2000°N 67.3056°E	[37]
	Pragian	410.8 ± 2.8		Velká Chuchle quarry Velká Chuchle, Prague, Czech Republic	Biologic: First appearance of Eognathodus sulcatus (Conodont).	50°00′53″N 14°22′21″E / 50.0147°N 14.3726°E	[38]
	Lochkovian	419.2 ± 3.2		Klonk, Prague, Czech Republic	Biologic: First appearance of Monograptus uniformis (graptolite).	49°51′18″N 13°47′31″E / 49.8550°N 13.7920°E	[3]

Silurian

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Přídolí		423.0 ± 2.3		Požáry Section, Řeporyje District, Prague, Czech Republic	Biologic: First appearance of Monograptus parultimus (Graptolite).	50°01′40″N 14°19′30″E / 50.0277°N 14.3249°E	[39]
Ludlow
	Ludfordian	425.6 ± 0.9		Sunnyhill, Ludlow, England	Imprecise GSSP. Biologic: Near first appearance of Saetograptus leintwardinensis (Graptolite).	52°21′33″N 2°46′38″W / 52.3592°N 2.7772°W	[40]
	Gorstian	427.4 ± 0.5		Pitch Coppice, Ludlow, U.K.	Biologic: First appearance Saetograptus (Colonograptus) varians	52°21′33″N 2°46′38″W / 52.3592°N 2.7772°W	[40]
Wenlock
	Homerian	430.5 ± 0.7		Whitwell Coppice, Homer, England	Biologic: First appearance of Cyrtograptus lundgreni (Graptolite).	52°36′56″N 2°33′53″W / 52.6156°N 2.5647°W	[40]
	Sheinwoodian	433.4 ± 0.8		Hughley Brook, Apedale, U.K.	Imprecise GSSP. Will be reexamined. Biologic: Currently between acritarch biozone 5 and last appearance of Pterospathodus amorphognathoides. Candidate boundaries are a conodont boundary (Ireviken datum 2) which is close to the murchisoni graptolite biozone.	52°34′52″N 2°38′20″W / 52.5811°N 2.6389°W	[3][40]
Llandovery
	Telychian	438.5 ± 1.1		Cefn-cerig Road, Llandovery, England	Biologic: Above extinction of Eocoelia intermedia, below lowest succeeding species Eocoelia curtisi (Brachiopod). Biologic: Near first appearance of Monograptus turriculatus (Graptolite).	51°58′12″N 3°47′24″W / 51.9700°N 3.7900°W	[39]
	Aeronian	440.8 ± 1.2		Trefawr Track, Llandovery, U.K.	Biologic: First appearance of Monograptus austerus sequens (Graptolite).	52°01′48″N 3°42′00″W / 52.0300°N 3.7000°W	[39]
	Rhuddanian	443.8 ± 1.5		Dob's Linn, Moffat, U.K.	Biologic: First appearance of Akidograptus ascensus and Parakidograptus acuminatus (Graptolite). 1.6 m above the base of the Birkhill Shale Formation.	55°26′24″N 3°16′12″W / 55.4400°N 3.2700°W	[39]

Ordovician

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Upper
	Hirnantian	445.2 ± 1.4		Wangjiawan section Wangjiawan, Yichang, China	Biologic: First appearance of Normalograptus extraordinarius (Graptolite). Climatic: Base of major positive carbon isotope excursion. Climatic: Beginning of sea-level fall associated with onset of a major glaciation.	30°59′03″N 111°25′11″E / 30.9841°N 111.4197°E	[41]
	Katian	453.0 ± 0.7		Black Knob Ridge section, Oklahoma, USA	Biologic: First appearance of Diplacanthograptus caudatus (Graptolite). Climatic: Just below base of Guttenberg carbon isotope excursion.	34°25′50″N 96°04′29″W / 34.4305°N 96.0746°W	[42]
	Sandbian	458.4 ± 0.9		Fågelsång section Sularp Brook, Skåne, Sweden	Biologic: First appearance of Nemagraptus gracilis (Graptolite). 1.4 m below a phosphorite marker bed.	55°42′49″N 13°19′32″E / 55.7137°N 13.3255°E	[43]
Middle
	Darriwilian	467.3 ± 1.1		Huangnitang Section Huangnitang, Zhejiang, China	Biologic: First appearance of Undulograptus austrodentatus (Graptolite).	28°51′14″N 118°29′23″E / 28.8539°N 118.4897°E	[44]
	Dapingian	470.0 ± 1.4		Huanghuachang section Huanghuachang, Yichang, China	Biologic: Lowest appearance of Baltoniodus triangularis (Conodont).	30°51′38″N 111°22′26″E / 30.8605°N 111.3740°E	[45][46]
Lower
	Floian	477.7 ± 1.4		Diabasbrottet quarry, Västergötland, Sweden	Biologic: Lowest appearance of Tetragraptus approximatus (Graptolite).	58°21′32″N 12°30′09″E / 58.3589°N 12.5024°E	[47]
	Tremadocian	485.4 ± 1.9		Greenpoint section Green Point, Newfoundland, Canada	Biologic: First appearance of Iapetognathus fluctivagus (Conodont). Biologic: Planktonic graptolites occur 4.8 m above boundary. Climatic: Coincides with a peak in carbon isotopes.	49°40′58″N 57°57′55″W / 49.6829°N 57.9653°W	[48]

Cambrian

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Furongian
	Stage 10	~489.5		Candidate sections: Duibian, Zhejiang, China Lawson Cove, Utah, USA	Candidates: Biologic: First appearance of Lotagnostus americanus (Trilobite). Biologic: First appearance of Cordylodus andresi (Conodont). Biologic: First appearance of Eoconodontus notchpeakensis (Conodont).	-	[49]
	Jiangshanian	~494		Duibian B Section Duibian, Zhejiang, China	Biologic: First appearance of Agnostotes orientalis (Trilobite).	28°48′57″N 118°36′54″E / 28.815967°N 118.614933°E	[50]
	Paibian	~497		Paibi section Paibi, Hunan, China	Biologic: First appearance of the agnostoid Glyptagnostus reticulatus (Trilobite). Climatic: Coincides with base of the Steptoean positive carbon isotope excursion (SPICE).	28°23′22″N 109°31′33″E / 28.3895°N 109.5257°E	[51]
Series 3
	Guzhangian	~500.5		Luoyixi section Luoyixi, Guzhang, Hunan, China	Biologic: First appearance of Lejopyge laevigata (Trilobite).	28°43′12″N 109°57′53″E / 28.7200°N 109.9647°E	[52]
	Drumian	~504.5		Drumian section Wheeler Shale, Utah, U.S.A.	Biologic: First appearance of Ptychagnostus atavus (Trilobite).	39°30′42″N 112°59′29″W / 39.5117°N 112.9915°W	[53]
	Stage 5	~509		Candidate sections: Wuliu-Zengjiayan, Guizhou, China Split Mountain, Nevada, USA Molodo river section, Bulunsky District, Sakha Republic	Biologic: First appearance of Oryctocephalus indicus (Trilobite). Biologic: First appearance of Ovatoryctocara granulata (Trilobite).	-	[54]
Series 2
	Stage 4	~514		None	Biologic: First appearance Arthricocephalus chauveaui (Trilobite species). Biologic: First appearance Olenellus or Redlichia (Trilobite genera).	-	[55]
	Stage 3	~521		None	Biologic: First appearance of trilobites (possibly Lemdadella)	-	[56][57]
Terreneuvian
	Stage 2	~529		None	Biologic: First appearance of small shelly fauna or archaeocyathids	-	-
	Fortunian	541.0 ± 1.0		Fortune head section, Newfoundland, Canada	Biologic: First appearance of Treptichnus pedum (trace fossil).	47°04′34″N 55°49′52″W / 47.0762°N 55.8310°W	[58]

Precambrian

Proterozoic

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Neoproterozoic
	Ediacaran	~635		Enorama Creek section Flinders Ranges, South Australia	Geologic: Worldwide distinct cap carbonates. Isotopic: Beginning of a distinctive pattern of secular changes in carbon isotopes.	31°19′53″S 138°38′00″E / 31.3314°S 138.6334°E	[59]
	Cryogenian	~720		Defined chronometrically now. GSSP is in progress.	-	-	[60]
	Tonian	1000		Defined chronometrically	-	-	[60]
Mesoproterozoic
	Stenian	1200		Defined chronometrically	-	-	[60]
	Ectasian	1400		Defined chronometrically	-	-	[60]
	Calymmian	1600		Defined chronometrically	-	-	[60]
Paleoproterozoic
	Statherian	1800		Defined chronometrically	-	-	[60]
	Orosirian	2050		Defined chronometrically	-	-	[60]
	Rhyacian	2300		Defined chronometrically	-	-	[60]
	Siderian	2500		Defined chronometrically	-	-	[60]

Archean

Epoch	Stage	Age (mya)	Status	GSSP location	Defining markers	Geographic Coordinates	References
Neoarchean		2800
Mesoarchean		3200
Paleoarchean		3600
Eoarchean		4000
Hadean		4567

See also

• Global Boundary Stratotype Section and Point (GSSP)
• International Commission on Stratigraphy (ICS)
• Geologic Time Scale
• History of the Earth
• Geological history of Earth

External links

• International Commission on Stratigraphy (ICS)

References

1. Walker, Mike; Johnsen, Sigfus; Rasmussen, Sune Olander; Popp, Trevor; Steffensen, Jørgen-Peder; Gibbard, Phil; Hoek, Wim; Lowe, John; Andrews, John; Björck, Svante; Cwynar, Les C.; Hughen, Konrad; Kershaw, Peter; Kromer, Bernd; Litt, Thomas; Lowe, David J.; Nakagawa, Takeshi; Newnham, Rewi; Schwander, Jakob (1 January 2009). "Formal definition and dating of the GSSP (Global Stratotype Section and Point) for the base of the Holocene using the Greenland NGRIP ice core, and selected auxiliary records". Journal of Quaternary Science 24 (1): 3–17. doi:10.1002/jqs.1227. Cite uses deprecated parameter |coauthors= (help)
2. Litt, Thomas; Philip Gibbard (2008). "Definition of a Global Stratotype Section and Point (GSSP) for the base of the Upper (Late) Pleistocene Subseries (Quaternary System/Period)" (PDF). Episodes 31 (2). Archived from the original (PDF) on 22 March 2014. Retrieved 14 September 2012.
3. "Global Boundary Stratotype Section and Point". International Commission of Stratigraphy. Retrieved 14 September 2012.
4. Aguirre, E; G. Pasini (1985). "The Pliocene - Pleistocene Boundary" (PDF). Episodes 8 (2): 116–120. Retrieved 14 September 2012.
5. Rio, Domenico; R. Sprovieri; D. Castradori; E. Di Stefano (1998). "The Gelasian Stage (Upper Pliocene): A new unit of the global standard chronostratigraphic scale" (PDF). Episodes 21 (2): 82–87. Retrieved 14 September 2012.
6. Castradori, D.; D. Rio; F. J. Hilgen; L. J. Lourens (1998). "The Global Standard Stratotype-section and Point (GSSP) of the Piacenzian Stage (Middle Pliocene)" (PDF). Episodes 21 (2): 88–93. Retrieved 14 September 2012.
7. Couvering, John A. Van; Davide Castradori; Maria Bianca Cita; Frederik J. Hilgen; Domenico Rio (2000). "The base of the Zanclean Stage and of the Pliocene Series" (PDF). Episodes 23 (3): 179. Retrieved 14 September 2012.
8. Hilgen, F. J.; S. Iaccarino; W. Krijgsman; G. Villa; C. G. Langereis; W. J. Zachariasse (2000). "The Global Boundary Stratotype Section and Point (GSSP) of the Messinian Stage (uppermost Miocene)" (PDF). Episodes 23 (3): 172–178. Retrieved 14 September 2012.
9. Hilgen, F. J.; Hayfaa Abdul Aziz, David Bice, Silvia Iaccarino, Wout Krijgsman, Klaudia Kuiper, Alessandro Montanari, Isabella Raffi, Elena Turco, Willem-Jan Zachariasse (2005). "The Global boundary Stratotype Section and Point (GSSP) of the Tortonian Stage (Upper Miocene) at Monte Dei Corvi" (PDF). Episodes 28 (1): 6–17. Retrieved 14 September 2012. Cite uses deprecated parameter |coauthors= (help)
10. Hilgen, F. J.; H. A. Abels; S. Iaccarino; W. Krijgsman; I. Raffi; R. Sprovieri; E. Turco; W. J. Zachariasse (2009). "The Global Stratotype Section and Point (GSSP) of the Serravallian Stage (Middle Miocene)" (PDF). Episodes 32 (3): 152–166. Retrieved 14 September 2012.
11. Steininger, Fritz F.; M. P. Aubry, W. A. Berggren, M. Biolzi, A. M. Borsetti, Julie E. Cartlidge, F. Cati, R. Corfield, R. Gelati, S. Iaccarino, C. Napoleone, F. Ottner, F. Rögl, R. Roetzel, S. Spezzaferri, F. Tateo, G. Villa, D. Zevenboom (1997). "The Global Stratotype Section and Point (GSSP) for the base of the Neogene" (PDF). Episodes 20 (1): 23–28. Retrieved 14 September 2012. Cite uses deprecated parameter |coauthors= (help)
12. Silva, Isabella Premoli; D. Graham Jenkins (1993). "Decision on the Eocene-Oligocene boundary stratotype" (PDF). Episodes 16 (3): 379–382. Retrieved 14 September 2012.
13. Molina, Eustoquio; Laia Alegret, Estibaliz Apellaniz, Gilen Bernaola, Fernando Caballero, Jaume Dinarès-Turell, Jan Hardenbol, Claus Heilmann-Clausen, Juan C. Larrasoana, Hanspeter Luterbacher, Simonetta Monechi, Silvia Ortiz, Xabier Orue-Etxebarria, Aitor Payros, Victoriano Pujalte, Francisco J. Rodríguez-Tobar, Flavia Tori, Josep Tosquella, Alfred Uchman (2011). "The Global Stratotype Section and Point (GSSP) for the base of the Lutetian Stage at the Gorrondatxe section, Spain" (PDF). Episodes 34 (2): 86–108. Retrieved 14 September 2012. Cite uses deprecated parameter |coauthors= (help)
14. Dupuis, C.; Aubry, M.-P., Steurbaut, E., Berggren, W.A., Ouda, K., Magioncalda, R., Cramer, B.S., Kent, D.V., Speijer, R.P. and Heilmann-Clausen, C. (2003). "The Dababiya Quarry section: lithostratigraphy, clay mineralogy, geochemistry and paleontology" (PDF). Micropaleontology 49 (1): 41–59. doi:10.2113/49.suppl_1.41. Retrieved 14 September 2012. Cite uses deprecated parameter |coauthors= (help)
15. Aubry, Marie-Pierre; Khaled Ouda, Christian Dupuis, William A., Berggren, John A. Van Couvering and the Members of the Working Group on the Paleocene/Eocene Boundary (2007). "The Global Standard Stratotype-section and Point (GSSP) for the base of the Eocene Series in the Dababiya section (Egypt)" (PDF). Episodes 30 (4): 271–286. Retrieved 14 September 2012. Cite uses deprecated parameter |coauthors= (help)
16. Schmitz, B.; Pujalte, V., Molina, E., Monechi, S., Orue-Etxebarria, X., Speijer, R. P., Alegret, L., Apellaniz, E., Arenillas, I., Aubry, M.-P., Baceta, J.-I., Berggren, W. A., Bernaola, G., Caballero, F., Clemmensen, A., Dinarès-Turell, J., Dupuis, C., Heilmann-Clausen, C., Orús, A. H., Knox, R., Martín-Rubio, M., Ortiz, S.,Payros, A., Petrizzo, M. R., von Salis, K., Sprong, J., Steurbaut, E., and Thomsen, E. (2011). "The global Stratotype Sections and Points for the bases of the Selandian (Middle Paleocene) and Thanetian (Upper Paleocene Paleocene) stages at Zumaia, Spain". Episodes 34 (4): 220–243. Cite uses deprecated parameter |coauthors= (help)
17. Molina, Eustoquio; Laia Alegret; Ignacio Arenillas; José A. Arz; Njoud Gallala; Jan Hardenbol; Katharina von Salis; Etienne Steurbaut; Noel Vandenberghe; Dalila Zaghibib-Turki (2006). "The Global Boundary Stratotype Section and Point for the base of the Danian Stage (Paleocene, Paleogene, "Tertiary", Cenozoic) at El Kef, Tunisia - Original definition and revision" (PDF). Episodes 29 (4): 263–278. Retrieved 14 September 2012.
18. Odin, Gilles S.; Michèle A. Lamaurelle (2001). "The global Campanian-Maastrichtian stage boundary" (PDF). Episodes 24 (4): 229–238. Retrieved 16 September 2012.
19. Kennedy, W. J.; I. Walaszczyk; W. A. Cobban (2005). "The Global Boundary Stratotype Section and Point for the base of the Turonian Stage of the Cretaceous: Pueblo, Colorado, U.S.A." (PDF). Episodes 28 (2): 93–104. Retrieved 16 September 2012.
20. Kennedy, W. J.; A. S. Gale; J. A. Lees; M. Caron (2004). "The Global Boundary Stratotype Section and Point (GSSP) for the base of the Cenomanian Stage, Mont Risou, Hautes-Alpes, France" (PDF). Episodes 27 (1): 21–32. Retrieved 16 September 2012.
21. Fernández-López, Sixto Rafael; Giulio Pavia; Elisabetta Erba; Myette Guiomar; Maria Helena Henriques; Roberto Lanza; Charles Mangold; Nicol Morton; Davide Olivero; Daniele Tiraboschi (2009). Episodes (PDF) 32 (4): 222–248 http://www.stratigraphy.org/GSSP/file16.pdf. Retrieved 17 September 2012. Missing or empty |title= (help)
22. Pavia, G.; R. Enay (1997). Episodes (PDF) 20 (1): 16–22 http://www.stratigraphy.org/GSSP/file17.pdf. Retrieved 17 September 2012. Missing or empty |title= (help)
23. Cresta, S.; A. Goy, S. Ureta, C. Arias, E. Barrón, J. Bernad, M. L. Canales, F. García-Joral, E. García-Romero, P. R. Gialanella, J. J. Gómez, J. A. González, C. Herrero, G. Martínez, M. L. Osete, N. Perilli, J. J. Villalaín (2001). "The Global Boundary Stratotype Section and Point (GSSP) of the Toarcian-Aalenian Boundary (Lower-Middle Jurassic)" (PDF). Episodes 24 (3): 166–175. Retrieved 17 September 2012. Cite uses deprecated parameter |coauthors= (help)
24. Meister, Christian; Martin Aberhan, Joachim Blau, Jean-Louis Dommergues, Susanne Feist-Burkhardt, Ernie A. Hailwood, Malcom Hart, Stephen P. Hesselbo, Mark W. Hounslow, Mark Hylton, Nicol Morton, Kevin Page, and Greg D. Price (2006). "The Global Boundary Stratotype Section and Point (GSSP) for the base of the Pliensbachian Stage (Lower Jurassic), Wine Haven, Yorkshire, UK" (PDF). Episodes 29 (2): 93–106. Retrieved 17 September 2012. Cite uses deprecated parameter |coauthors= (help)
25. Bloos, Gert; Kevin N. Page (2002). "Global Stratotype Section and Point for base of the Sinemurian Stage (Lower Jurassic)" (PDF). Episodes 25 (1): 22–28. Retrieved 17 September 2012.
26. Mietto, P.; Manfrin S., Preto N., Rigo M., Roghi G., Gianolla P., Posenato R., Muttoni G., Nicora A., Buratti N., Cirilli S., Spötl C. (2012). "The Global Boundary Stratotype Section and Point (GSSP) of the Carnian stage (Late Triassic) at Prati di Stuores/Stuores Wiesen section (Southern Alps, NE Italy)" (PDF). Episodes 35: 414–430. Retrieved 4 February 2013. Cite uses deprecated parameter |coauthors= (help)
27. Brack, Peter; Hans Rieber; Alda Nicora; Roland Mundil (2005). "The Global boundary Stratotype Section and Point (GSSP) of the Ladinian Stage (Middle Triassic) at Bagolino (Southern Alps, Northern Italy) and its implications for the Triassic time scale" (PDF). Episodes 28 (4): 233–244. Retrieved 18 September 2012.
28. Yugan, Jin; Yue Wang; Charles Henderson; Bruce R. Wardlaw; Shuzhong Shen; Changqun Cao (2006). "The Global Boundary Stratotype Section and Point (GSSP) for the base of Changhsingian Stage (Upper Permian)" (PDF). Episodes 29 (3): 175–182. Retrieved 18 September 2012.
29. Yugan, Jin; Shuzhong Shen; Charles M. Henderson; Xiangdong Wang; Wei Wang; Yue Wang; Changqun Cao; Qinghua Shang (2006). "The Global Stratotype Section and Point (GSSP) for the boundary between the Capitanian and Wuchiapingian Stage (Permian)" (PDF). Episodes 29 (4): 253–262. Retrieved 18 September 2012.
30. Davydov, Vladimir I.; Brian F. Glenister; Claude Spinosa; Scott M. Ritter; V. V. Chernykh; B. R. Wardlaw; W. S. Snyder (1998). "Proposal of Aidaralash as Global Stratotype Section and Point (GSSP) for base of the Permian System" (PDF). Episodes 21 (1): 11–18. Retrieved 18 September 2012.
31. Lane, H. Richard; Paul L. Brenckle; J. F. Baesemann; Barry Richards (1999). "The IUGS boundary in the middle of the Carboniferous: Arrow Canyon, Nevada, USA" (PDF). Episodes 22 (4): 272–283. Retrieved 18 September 2012.
32. Paproth, Eva; Raimund Feist; Gerd Flajs (1991). "Decision on the Devonian - Carboniferous boundary stratotype" (PDF). Episodes 14 (4): 331–336. Retrieved 18 September 2012.
33. Klapper, G.; R. Feist; R. T. Becker; M. R. House (1993). "Definition of the Frasnian/Famennian Stage boundary" (PDF). Episodes 16 (4): 433–441. Retrieved 20 September 2012.
34. Klapper, Gilbert; Raimund Feist; Michael R. House (1987). "Decision on the Boundary Stratotype for the Middle/Upper Devonian Series Boundary" (PDF). Episodes 10 (2): 97–101. Retrieved 20 September 2012.
35. Walliser, O. H.; P. Bultynck; K. Weddige; R. T. Becker; M. R. House (1995). "Definition of the Eifelian-Givetian Stage boundary" (PDF). Episodes 18 (3): 107–115. Retrieved 20 September 2012.
36. Ziegler, W.; G. Klapper (1985). "Stages of the Devonian System" (PDF). Episodes 8 (2): 104–109. Retrieved 20 September 2012.
37. Yolkin, E. A.; A. I. Kim; K. Weddige; J. A. Talent; M. R. House (1997). "Definition of the Pragian/Emsian Stage boundary" (PDF). Episodes 20 (4): 235–240. Retrieved 20 September 2012.
38. Chlupac, Ivo; William A. Oliver Jr. (1989). "Decision on the Lochkovian - Pragian Boundary Stratotype (Lower Devonian)" (PDF). Episodes 12 (2): 109–113. Retrieved 20 September 2012.
39. Holland, C. H. (1985). "Series and Stages of the Silurian System" (PDF). Episodes 8 (2): 101–103. Retrieved 19 September 2012.
40. Holland, C. H. (1982). "The State of Silurian Stratigraphy" (PDF). Episodes 5 (3): 21–23. Retrieved 19 September 2012.
41. Chen, Xu; Jiayu Rong; Junxuan Fan; Renbin Zhan; Charles E. Mitchell; David A. T. Harper; Michael J. Melchin; Ping'an Peng; Stan C. Finney; Xiaofeng Wang (2006). "The Global Boundary Stratotype Section and Point (GSSP) for the base of the Hirnantian Stage (the uppermost of the Ordovician System)" (PDF). Episodes 29 (3): 183–196. Retrieved 20 September 2012.
42. Goldman, Daniel; Stephen A. Leslie; Jaak Nõlvak; Seth Young; Stig M. Bergström; Warren D. Huff (2007). "The Global Stratotype Section and Point (GSSP) for the base of the Katian Stage of the Upper Ordovician Series at Black Knob Ridge, Southeastern Oklahoma, USA" (PDF). Episodes 30 (4): 258–270. Retrieved 20 September 2012.
43. Bergström, Stig M.; S. C. Finney; Chen Xu; Christian Pålsson; Wang Zhi-hao; Yngve Grahn (2000). "A proposed global boundary stratotype for the base of the Upper Series of the Ordovician System: The Fågelsång section, Scania, southern Sweden" (PDF). Episodes 23 (2): 102–109. Retrieved 20 September 2012.
44. Mitchell, C. E.; Chen Xu; S. M. Bergström; Zhang Yuan-dong; Wang Zhi-hao; B. D. Webby; S. C. Finney (1997). "Definition of a global boundary stratotype for the Darriwilian Stage of the Ordovician System" (PDF). Episodes 20 (3): 158–166. Retrieved 20 September 2012.
45. Wang, Xiaofeng; Svend Stouge, Bernd-D. Erdtmann, Xiaohong Chen, Zhihong Li, Chuanshang Wang, Qingluan Zeng, Zhiqiang Zhou, Huiming Chen (2005). "A proposed GSSP for the base of the Middle Ordovician Series: the Huanghuachang section, Yichang, China" (PDF). Episodes 28 (2): 105–117. Retrieved 20 September 2012. Cite uses deprecated parameter |coauthors= (help)
46. Wang, Xiaofeng; Svend Stouge, Chen Xiaohong, Li Zhihong, Wang Chuanshang, Stan C. Finney, Zeng Qingluan, Zhou Zhiqiang, Chen Huiming, Bernd-D. Erdtmann (2009). "The Global Stratotype Section and Point for the base of the Middle Ordovician Series and the Third Stage (Dapingian)" (PDF). Episodes 32 (2): 96–113. Retrieved 20 September 2012. Cite uses deprecated parameter |coauthors= (help)Note: there is an apparent typo in the article referenced; they give the coordinates as "a latitude of 30°51’37.8"N and a longitude of110°22’26.5"E", but their map and location description better corresponds to 30°51’37.8"N 111°22’26.5"E.
47. Bergström, Stig M.; Anita Löfgren; Jörg Maletz (2004). "The GSSP of the Second (Upper) Stage of the Lower Ordovician Series: Diabasbrottet at Hunneberg, Province of Västergötland, Southwestern Sweden" (PDF). Episodes 27 (4): 265–272. Retrieved 20 September 2012.
48. Cooper, R. A.; G. S. Nowlan; S. H. Williams (2001). "Global Stratotype Section and Point for base of the Ordovician System" (PDF). Episodes 24 (1): 19–28. Retrieved 20 September 2012.
49. Landing, E.; Westrop, S.R.; Adrain, J.M. (19 September 2011). "The Lawsonian Stage - the Eoconodontus notchpeakensis FAD and HERB carbon isotope excursion define a globally correlatable terminal Cambrian stage". Bulletin of Geosciences: 621–640. doi:10.3140/bull.geosci.1251.
50. "GSSP for Jiangshanian". Retrieved 12 November 2012.
51. Peng, Shanchi; Babcock, Loren; Robison, Richard; Lin, Huanling; Rees, Margaret; Saltzman, Matthew (30 November 2004). "Global Standard Stratotype-section and Point (GSSP) of the Furongian Series and Paibian Stage (Cambrian)" (PDF). Lethaia 37 (4): 365–379. doi:10.1080/00241160410002081. Retrieved 14 September 2012.
52. Peng, Shanchi; Loren E. Babcok; Jingxun Zuo; Huanling LIn; Xuejian Zhu; Xianfeng Yang; Richard A. Ribosn; Yuping Qui; Gabriella Bagnoli; Yong'an Chen (2009). "The Global Boundary Stratotype Section and Point (GSSP) of the Guzhangian Stage (Cambrian) in the Wuling Mountains, Northwestern Hunan, China" (PDF). Episodes 32 (1): 41–55. Retrieved 14 September 2012.
53. Babcock, Loren E.; Richard A. Robison; Margaret N. Rees; Shanchi Peng; Matthew R. Saltzman (2007). "The Global boundary Stratotype Section and Point (GSSP) of the Drumian Stage (Cambrian) in the Drum Mountains, Utah, USA" (PDF). Episodes 30 (2): 85–95. Retrieved 14 September 2012.
54. Gozalo, Rodolfo; Álvarez, María Eugenia Dies; Vintaned, José Antonio Gámez; Zhuravlev, Andrey Yu.; Bauluz, Blanca; Subías, Ignacio; Chirivella Martorell, Juan B.; Mayoral, Eduardo; Gursky, Hans-Jürgen; Andrés, José Antonio; Liñán, Eladio (1 December 2011). "Proposal of a reference section and point for the Cambrian Series 2-3 boundary in the Mediterranean subprovince in Murero (NE Spain) and its intercontinental correlation". Geological Journal: n/a–n/a. doi:10.1002/gj.1330. Cite uses deprecated parameter |coauthors= (help)
55. Peng, S.C.; Babcock, L.E. (21 September 2011). "Continuing progress on chronostratigraphic subdivision of the Cambrian System" (PDF). Bulletin of Geosciences: 391–396. doi:10.3140/bull.geosci.1273. Retrieved 21 November 2012.
56. "GSSP Table - Paleozoic Era". Retrieved 15 November 2012.
57. Yuan, J.L.; Zhu, X.J.; Lin, J.P.; Zhu, M.Y. (22 September 2011). "Tentative correlation of Cambrian Series 2 between South China and other continents" (PDF). Bulletin of Geosciences: 397–404. doi:10.3140/bull.geosci.1274. Retrieved 23 November 2012.
58. Brasier, Martin; John Cowie; Michael Taylor (1994). "Decision on the Precambrian-Cambrian boundary stratotype" (PDF). Episodes 17 (1-2): 95–100. Retrieved 14 September 2012.
59. Knoll, Andrew; Walter, Malcolm; Narbonne, Guy; Christie-Blick, Nicholas (28 February 2006). "The Ediacaran Period: a new addition to the geologic time scale" (PDF). Lethaia 39 (1): 13–30. doi:10.1080/00241160500409223. Retrieved 14 September 2012.
60. Plumb, K. A. (1991). "New Precambrian timescale" (PDF). Episodes 14 (2). Retrieved 14 September 2012.