This is a view of Stevns' Cliffs (Stevns klint), Denmark in July 2005. Credit: Dan Simon.

Cenozoic geochronology is the science of applying dates in the past to apparently Cenozoic rocks.

Notations

Let

1. ALMA represent the Asian Land Mammal Age,
2. b2k represent before AD 2000,
3. BP represent before present, as the chart is for 2008, this may require an added -8 for b2k,
4. ELMMZ represent the European Land Mammal Mega Zone,
5. FAD represent first appearance datum,
6. GICC05 represent Greenland Ice Core Chronology 2005,
7. GRIP represent Greenland Ice Core Project,
8. GSSP represent Global Stratotype Section and Point,
9. ICS represent the International Commission on Stratigraphy,
10. IUGS represent the International Union of Geological Sciences,
11. LAD represent last appearance datum,
12. Ma represent Megaannum, or million years ago, or -10⁶ b2k,
13. NALMA represent the North American Land Mammal Age,
14. NGRIP represent North Greenland Ice Core Project, and
15. SALMA represent South American Land Mammal Age.

"The term b2 k [b2k] refers to the ice-core zero age of AD 2000; note that this is 50 years different from the zero yr for radiocarbon, which is AD 1950 [...]."^[1]

Cenozoic time frames

Cenozoic

Cretaceous-Paleogene clay is in the Geulhemmergroeve tunnels near Geulhem, The Netherlands. Credit: Wilson44691.

In the Badlands near Drumheller, Alberta, erosion has exposed the K-Pg boundary. Credit: Glenlarson.

The KT boundary at Trinidad Lake State Park, Colorado, USA, is at the color change. Credit: Nationalparks.

In the image on the right, the finger is pointing to the K/Pg boundary clay in the Geulhemmergroeve tunnels near Geulhem, The Netherlands.

The second from the top image on the right shows the K-Pg boundary in the Badlands near Drumheller, Alberta, where glacial and post-glacial erosion have exposed the boundary.

The cliffs at Stevns, in the image at the top of this page, have the highest iridium occurrence in the Alvarez analysis.

The K-Pg boundary at Trinidad Lake State Park, Colorado, USA, in the fourth image on the right, occurs at the color change from dark gray or black to the Cenozoic light tans and browns.

"Our assessment of published radiometric dates suggests the following best biochronologic age estimates for Cenozoic Epoch boundaries: Pliocene/Pleistocene: <2 Ma; Miocene/Pliocene: ~5 Ma; Oligocene/Miocene: ~23.5 Ma; Eocene/Oligocene: ~37 Ma; Paleocene/Eocene: ~56.5 Ma; Cretaceous/Tertiary: ~66 Ma. The radiometric data on which these age estimates are based, especially in the Paleogene, are biased toward those obtained from high-temperature minerals; age estimates based on radiometric dates from glauconites tend to be younger, particularly in the Paleogene (for example, Odin and others, 1982)."^[6]

Quaternary

Calculated Greenland temperatures are through the last 20,000 years. Credit: Willi Dansgaard.

The "whole change elapsed just opposite the course of events that characterized the great glacial oscillations with sudden warming followed by slow cooling. Therefore, the two phenomena hardly have the same cause."^[7]

"In the Greenland ice cores, the Pleistocene–Holocene transition is chronologically constrained between two clearly defined tephra horizons: the Saksunarvatn tephra (1409.83 m depth) and the Vedde Ash (1506.14 m depth). These are dated at 10 347 yr b2 k (counting uncertainty 89 yr) and 12 171 yr (counting uncertainty 114 yr) b2 k, respectively."^[1]

Holocene

The base of the Holocene Series/Epoch is defined in the NGRIP ice-core record at the horizon which shows the clearest signal of climatic warming, an event that marks the end of the last cold episode (Younger Dryas Stadial/Greenland Stadial 1) of the Pleistocene. Credit: Mike Walker, Sigfus Johnsen, Sune Olander Rasmussen, Trevor Popp, Jørgen-Peder Steffensen, Phil Gibbard, Wim Hoek, John Lowe, John Andrews, Svante Björck, Les C. Cwynar, Konrad Hughen, Peter Kershaw, Bernd Kromer, Thomas Litt, David J. Lowe, Takeshi Nakagawa, Rewi Newnham and Jakob Schwander.

The Holocene starts at ~11,700 b2k and extends to the present.

"A timescale based on multi-parameter annual layer counting provides an age of 11 700 calendar yr b2k (before AD 2000) for the base of the Holocene, with a maximum counting error of 99 yr."^[1]

"The base of the Holocene Series/Epoch is defined in the NGRIP ice-core record [above] at the horizon which shows the clearest signal of climatic warming, an event that marks the end of the last cold episode (Younger Dryas Stadial/Greenland Stadial 1) of the Pleistocene [...]."^[1]

19th Century

Napoleon I on his Imperial Throne is portrayed by Jean-Auguste-Dominique Ingres (French, 1806), oil on canvas. Credit: Jean-Auguste-Dominique Ingres.

A Navajo blanket was made circa 1880. Credit: Unknown Navajo weaver, pre-1889.

The painting Napoleon I on his Imperial Throne dates to 1806 by artist Jean-Auguste-Dominique Ingres.

"This blanket [in the image centered] was woven at the end of the "wearing blanket era," just as the railroad came into the Southwest in 1881. The heavier handspun yarns and synthetic dyes are typical of pieces made during the transition from blanket weaving to rug weaving."-Ann Hedlund, Arizona State Museum.

Charred material from the Lake Pátzcuaro Basin, Mexico, was radiocarbon dated at 1715-1895 AD (120 b2k intercept).^[8]

18th Century

The more recent dated logboat of Ireland is from or known as Bond's Bridge, Cos AmlaghJTyrone, to 245 ± 15 b2k.^[9]

17th Century

A logboat from Northern Ireland designated GrN-14744 dates to 305 ± 30 b2k.^[9]

16th Century

LiDAR gave the power to see underneath the lava that covers Angamuco. Credit: Chris Fisher.{{fairuse}}

A logboat from Ireland (Derryloughan B, Co. Tyrone) designated GrN-14738 dates to 410 ± 35 b2k.^[9]

Angamuco "occupied 26 square kilometers of land instead of 13 square kilometers."^[10]

"That is a huge area with a lot of people and a lot of architectural foundations that are represented."^[11]

"If you do the maths, all of a sudden you are talking about 40,000 building foundations up there, which is [about] the same number of building foundations that are on the island of Manhattan."^[11]

Angamuco "had an unusual layout, with big structures like pyramids and open plazas situated around the edges rather than in the center."^[10]

"The Purépecha people existed at the same time as the Aztecs. While they are nowhere near as popular as their rivals, they were still a major civilization and had an imperial capital called Tzintzuntzan in western Mexico. Based on [...] LiDAR scans, though, Angamuco is even bigger Tzintzuntzan. It likely wasn't as densely populated, but [...] it's now the biggest city in western Mexico during that period that we know of."^[10]

"In I523 Cortes quietly appropriated for himself the great Tarascan-held silver district of Tamazula (Jalisco)."^[12]

Late Middle Ages

Changes in the ¹⁴C record, which are primarily (but not exclusively) caused by changes in solar activity, are graphed over time. Credit: Leland McInnes.

The Shroud of Turin: modern photo of the face, is shown positive left, digitally processed image right. Credit: Dianelos Georgoudis.

The Late Middle Ages extends from about 700 b2k to 500 b2k.

Italian humanism began in the first century of the late Middle Ages (c.1350-1450).^[13]

The processed image at the right in the images on the right is the product of the application of digital filters. Digital filters are mathematical functions that do not add any information to the image, but transform it in such a way that information already present in it becomes more visible or easier to appreciate by the naked eye. The processed image was produced by inverting the brightness of the pixels in the positive image but without inverting their hue, and then by increasing both the brightness contrast and the hue saturation. Finally noise and so-called “salt and pepper” filters automatically removed the noisy information from the original image which hinders the appreciation of the actual face. To my knowledge the resulting image is the best available and indeed the only one that reveals the color information hidden in the original.

Radiocarbon dating of a corner piece of the shroud placed it between the years 1260 and 1390,^[14] in the High to Late Middle Ages, which is consistent with "its first recorded exhibition in France in 1357."^[15]

"Italy from the peace of Lodi to the first French invasion (1454-94): the era of equilibrium"^[13] is near the end of the late Middle Ages.

Charred materials from the Lake Pátzcuaro Basin, Mexico, were radiocarbon dated at 1170-1300 AD (680 b2k intercept), 1230-1315 AD (665 b2k intercept), 1300-1415 AD (605 b2k intercept), 1320-1535 AD (540 b2k intercept) and 1320-1435 AD (500 b2k intercept).^[8]

The Little Ice Age (LIA) appears to have lasted from about 1218 (782 b2k) to about 1878 (122 b2k).

High Middle Ages

The map shows the geographical distribution of the archaeological sites sampled. Credit: Nicole Maca-Meyer, Matilda Arnay, Juan Carlos Rando, Carlos Flores, Ana M González, Vicente M Cabrera, José M Larruga.

The High Middle Ages date from around 1,000 b2k to 700 b2k.

Mitochondrial "DNA analysis (HVRI sequences and RFLPs) [have been performed from] aborigine remains around 1000 years old. The sequences retrieved show that the Guanches possessed U6b1 lineages that are in the present day Canarian population, but not in Africans. In turn, U6b, the phylogenetically closest ancestor found in Africa, is not present in the Canary Islands. Comparisons with other populations relate the Guanches with the actual inhabitants of the Archipelago and with Moroccan Berbers. This shows that, despite the continuous changes suffered by the population (Spanish colonisation, slave trade), aboriginal mtDNA lineages constitute a considerable proportion of the Canarian gene pool. Although the Berbers are the most probable ancestors of the Guanches, it is deduced that important human movements have reshaped Northwest Africa after the migratory wave to the Canary Islands."^[16]

The "sublineage U6b1 is the most prevalent of the U6 subhaplogroup in the Canarian population,⁴ and has still not been detected in North Africa."^[16]

"This survey includes 131 teeth, corresponding to 129 different individuals, belonging to 15 archaeological sites sampled from four of the seven Canary Islands and dated around 1000 years old [image on the right]."^[16]

"The Canarian-specific U6b1 sequences are also found in high frequency (8.45%), corroborating the fact that these lineages were already present in the aboriginal population. Three additional founder haplotypes⁴ were also detected (260, 069 126 and 126 292 294), all of them showing equal or higher frequencies than in the present day Canarian population."^[16]

"The detection in the Guanches of the most abundant haplotype of the U6b1 branch, also found in present day islanders,⁴ points to a significant continuity of the aboriginal maternal gene pool."^[16]

"The [...] estimated age of the [U6b1] subgroup is around 6000 years,²⁹ which predates the arrival of the first human settlers to the Islands.¹"^[16]

Charred materials from the Lake Pátzcuaro Basin, Mexico, were radiocarbon dated at 970-1,170 AD (885 b2k intercept) and 1,010-1275 AD (775 b2k intercept).^[8]

Medieval Warm Period

Northern hemisphere temperature reconstructions are for the past 2,000 years. Credit: Global Warming Art.

The figure shows the number of samples in time for the Central European oak chronology. Credit: Stand.

The center of the graph shows the time axis of conventionally dated historical events. Upper and lower coordinates show reconstructed time tables. The black triangles mark the phantom years. Credit: Hans-Ulrich Niemitz.

The Medieval Warm Period (MWP) dates from around 1150 to 750 b2k.

"A proof-of-concept self-calibrating chronology [based upon the Irish Oak chronology] clearly demonstrates that third order polynomials provide a series of statistical calibration curves that highlight lacunae in the samples."^[17]

As indicated in the figures, the data used in the plots comes from radiocarbon dating of Irish Oaks.^[18]

Gaps occur near the 1070s and 1470s b2k during the rising Δ¹⁴C values.

"The number of suitable samples of wood, which connect Antiquity and the Middle Ages is very small [shown in the second figure on the left]. But only a great number of samples would give certainty against error. For the period about 380 AD we have only 3, for the period about 720 AD only 4 suitable samples of wood (Hollstein 1980,11); usually 50 samples serve for dating."^[19]

"The center of the graph [in the third image on the left] shows the time axis of conventionally dated historical events. Upper and lower coordinates show reconstructed time tables. The black triangles mark the phantom years."^[19]

"In Frankfurt am Main archaeological excavations did not find any layer for the period between 650 and 910 AD."^[19]

Early Middle Ages

Third order polynomials provide a series of statistical calibration curves that highlight lacunae in the carbon-14 samples. Credit: Gunnar Heinsohn.

The Δ¹⁴C values in a chronology can clearly be used to identify apparent catastrophic gaps and catastrophic rises in carbon-14. Credit: Gunnar Heinsohn.

The Early Middle Ages date from around 1,700 to 1,000 b2k.

At left is an attempt to correlate the change in ¹⁴C with time before 1950. The different data sets are shown with different colored third order polynomial fits to each data set.

"The Δ¹⁴C values in a chronology can clearly be used to identify catastrophic gaps and catastrophic rises in carbon-14."^[20]

The first four gaps have a jump up in ¹⁴C with a fairly quick return to the calibration curve shown in the figure on the second left. However, from about 2000 b2k there is a steady rise in the Δ¹⁴C values.

Imperial Antiquity

In Felix Romuliana, "the construction [...] is [...] Imperial Antique (1st-3rd c. [1900-1700 b2k]), and sometimes even late Hellenistic, [in] appearance."^[20]

Subatlantic period

The archaeological site of Tzintzuntzan is the capital of the Tarascan state. Credit: Hajor.{{free media}}

The "calibration of radiocarbon dates at approximately 2500-2450 BP [2500-2450 b2k] is problematic due to a "plateau" (known as the "Hallstatt-plateau") in the calibration curve [...] A decrease in solar activity caused an increase in production of ¹⁴C, and thus a sharp rise in Δ ¹⁴C, beginning at approximately 850 cal (calendar years) BC [...] Between approximately 760 and 420 cal BC (corresponding to 2500-2425 BP [2500-2425 b2k]), the concentration of ¹⁴C returned to "normal" values."^[21]

"The main discontinuity in the climatic condition during the Bronze Age and Iron Age transition can be identified in the boundary from Subatlantic to Subboreal (2800-2500 BP; 996/914-766/551 2σ cal. BC). Such period “has globally been identified as a time of marked climatic change. Stratigraphical, paleobotanical and archaeological evidence point to a change from a dry and warm to a more humid and cool climate in central and northwestern Europe” (Tinner et al. 2003). The climatic deterioration which characterizes this chronological range is directly responsible of the plateau in the calibration curve between 760 and 420 BC (2500-2425 BP) (see chapter 4.3.2.1). The climatic oscillation around 2700 BP (896/813 2σ cal. BC) has been detected worldwide. Van Geel et al. (1996, 1998) and Speranza et al. (2002) found an abrupt shift around 850 BC in changing species composition of peat-forming mosses in European Holocene raised bog deposits. The change was from mosses preferring warm conditions to those preferring colder and wetter environments. Archaeological evidence supports such a change. Bronze Age settlements located in the Netherlands were suddenly abandoned after a long period of occupation which last around one millennium (Dergachev et al. 2004). Other studies confirmed the climatic discontinuity; Schilman et al. (2001) studied δ18O and δ13C in deposits from the southeastern Mediterranean, off Israel, and recognized the presence of two humid events in the time ranges of 3500-3000 BP (1884/1772-1263/1215 2σ cal. BC) and 1700-1000 BP (332/389-1016/1030 2σ cal. AD) and a period of arid conditions between 3000 and 1700 BP (1263/1215 2σ cal. BC- 332/389 2σ cal. AD). Barber and Langdon (2001) identified three main long climatic deteriorations 2900-2830 BP (1119/1037-1012/934 2σ cal. BC), 2630-2590 BP (810/797-801/788 2σ cal. BC) and 1550-1400 BP (430/549-637/658 2σ cal. AD) through the analysis of plant macrofossils in a peat deposit of Walton Moss located in Northern England and comparing such data with a temperature reconstruction based on chironomids in the sediment of a nearby lake."^[22]

"Hallstatt disaster"

"Hallstatt disaster" refers to the plateau located in the calibration curve between 760 and 420 cal BC (2500-2425 BP). Credit: Giacomo Capuzzo.{{fairuse}}

"With the term “Hallstatt disaster” the scientific community refers to the plateau located in the calibration curve between 760 and 420 cal BC (2500-2425 BP) [the graph on the right]. The term is due to the chronological analogy to the Hallstatt society which developed in the late Bronze Age and the beginning of Iron Age in the northern part of the Alps (Austria). The flat shape of the calibration curve in this time-span is the result of the decrease, and hence the return to normal values, of the percentage of ¹⁴C after a period characterized by an increase in the concentration of radiocarbon in the atmosphere, which is mirrored in the calibration curve as a sharp descent between 850 and 760 BC (2700-2450 BP) (Speranza et al. 2000). As asserted by many authors (Van Geel et al. 1996; Van Geel et al. 1998; Tinner et al. 2003; Dergachev et al. 2004; Van der Plicht et al. 2004; Swindles et al. 2007) the chronological range 850-760 BC is characterized by an abrupt increase of the amount of ¹⁴C in the atmosphere and it corresponds chronologically to the boundary from Subatlantic to Subboreal (2800-2500 BP), which “has globally been identified as a time of marked climatic change. Stratigraphical, paleobotanical and archaeological evidence point to a change from a dry and warm to a more humid and cool climate in central and northwestern Europe” (Tinner et al. 2003)."^[22]

Subboreal period

The "period around 850-760 BC, [2850-2760 b2k, is] characterised by a decrease in solar activity and a sharp increase of Δ ¹⁴C [...] the local vegetation succession, in relation to the changes in atmospheric radiocarbon content, shows additional evidence for solar forcing of climate change at the Subboreal - Subatlantic transition."^[21]

The "Holocene climatic optimum in this interior part of Asia [Lake Baikal] corresponds to the Subboreal period 2.5–4.5 ka".^[23]

The "apparent reality of social equality testified by LBA urnfield burials can be definitely discarded at the Iron Age transition by the archaeological excavation at the Hexenbergle site, near Wehringen in Bayern (Germany). The monumental radiocarbon dated mound with a cremation burial of an adult male accompanied by a great amount of objects, including a sword, elements decorating a wagon and an extensive set of painted pottery (Hennig 1995). The dendrochronological date obtained on the wagon (778±5BC) provides a precise temporal location for an upper-class deceased with sepulchral paraphernalia in the Hallstatt period (Friedrich & Henning 1995, 1996)."^[22]

Iron Age

Photographs of three of the originally nine iron beads from Gerzeh, Lower Egypt, from left UC10738, UC10739 and UC10740. Credit: Thilo Rehren, Tamás Belgya, Albert Jambon, György Káli, Zsolt Kasztovszky, Zoltán Kis, Imre Kovács, Boglárka Maróti, Marcos Martinón-Torres, Gianluca Miniaci, Vincent C. Pigott, Miljana Radivojević, László Rosta, László Szentmiklósi, Zoltán Szőkefalvi-Nagy.

Comparison of neutron radiography and an optical photograph of an iron bead is shown. Credit: Thilo Rehren, Tamás Belgya, Albert Jambon, György Káli, Zsolt Kasztovszky, Zoltán Kis, Imre Kovács, Boglárka Maróti, Marcos Martinón-Torres, Gianluca Miniaci, Vincent C. Pigott, Miljana Radivojević, László Rosta, László Szentmiklósi, Zoltán Szőkefalvi-Nagy.

The iron age history period began between 3,200 and 2,100 b2k.

"The earliest known iron artefacts are nine small beads securely dated to circa 3200 BC, from two burials in Gerzeh, northern Egypt."^[24]

"Since both tombs are securely dated to Naqada IIC–IIIA, c 3400–3100 BC (Adams, 1990: 25; Stevenson, 2009: 11–31), the beads predate the emergence of iron smelting by nearly 2000 years, and other known meteoritic iron artefacts by 500 years or more (Yalçın 1999), giving them an exceptional position in the history of metal use."^[24]

The image on the left uses neutron radiography to show the metal underneath the corrosion.

"Bead UC10738 [in the image on the right] has a maximum length of 1.5 cm and a maximum diameter of 1.3 cm, bead UC10739 is 1.7 cm by 0.7 cm, and bead UC10740 is 1.7 cm by 0.3 cm. All three beads are of rust-brown colour with a rough surface, indicative of heavy iron corrosion. Initial analysis by [proton–induced X–ray fluorescence] pXRF indicated an elevated nickel content of the surface of the beads, in the order of a few per cent, and their magnetic property suggested that iron metal may be present in their body (Jambon, 2010)."^[24]

The earliest-known iron artifacts are nine small beads dated to 3200 BC, which were found in burials at Gerzeh, Lower Egypt. They have been identified as meteoric iron shaped by careful hammering.^[25] Meteoric iron, a characteristic iron–nickel alloy, was used by various ancient peoples thousands of years before the Iron Age. Such iron, being in its native metallic state, required no smelting of ores.^[26][27]

"After a typological analysis and a cross-dating of bronze artifacts recovered north and south of the Alps, the Roman school of Peroni set the 1020 [3020 b2k] as the beginning of the Iron Age (De Marinis 2005, p. 21; Pacciarelli 2005). The date is in agreement with the chronology supported by Lothar Sperber (Sperber 1987). The recent works of Nijboer based on the analysis of radiocarbon dates from Latial contexts agree with this high chronology (Nijboer et al. 1999-2000; Nijboer & Van der Plicht 2008; Van der Plicht et al. 2009)."^[22]

Bronze Age

A general world-wide use of bronze occurred between 5300 and 2600 b2k.

"The first (purely typological) studies on Early Bronze Age (EBA) assemblages in the Jordan Valley settled on the turn of the 4th/3rd millennium BC [mark] the beginnings of the earliest Bronze Age culture (Albright 1932; Mallon 1932)."^[28]

"In the Chalcolithic/earliest Bronze Age I period (c. 4500±3000 cal BC), copper was mined in open galleries from the massive brown sandstone deposit, which consisted of thick layers of the copper carbonate malachite and chalcocite, a copper sulphide."^[29]

Late Bronze Ages

The Late Bronze Ages begin about 3550 b2k and end about 2900 b2k.

The Pátzcuaro Basin is "on the Central Mexican Altiplano [19° 36′ N 101° 39′ W 2,033–3,000 meters above sea level (m asl)] [...] The earliest occupation is indicated by maize pollen in lake cores [sometime between 1690 and 940 B.C. (43, 47, 49)]."^[8]

The "abandonment of lakeshore Swiss pile-dwellings has been dated to around 1520 BC [3520 b2k] (Menotti 2001). [Slightly] "later in time episodes of flood events and lake-level highstand at 3100 BP (1415/1311 2σ cal. BC) and 2800 BP (996/914 2σ cal. BC) have been recently detected in the Southern Alps, in the sediment cores extracted from the Lake Ledro, located in the province of Trento (Joannin et al. 2014)."^[22]

Radiocarbon "data indicate that the New Kingdom of Egypt started between 1570 and 1544 B.C.E [3570 - 3544 b2k]."^[30]

Middle Bronze Ages

Fresco of The Fisherman is from Akrotiri, Santorini, Greece at a height of 1.10 m. Credit: Yann Forget.{{free media}}

The Middle Bronze Ages begin about 4100 b2k and end about 3550 b2k.

The Fisherman is a Minoan Bronze Age fresco from Akrotiri, on the Aegean island of Santorini (classically Thera), dated to the Neo-Palatial period (c. 1640–1600 BC). The settlement of Akrotiri was buried in volcanic ash (dated by radiocarbon dating to c. 1627 BC [c. 3626 b2k]) by the Minoan eruption on the island, which preserved many Minoan frescoes like this.

High precision radiocarbon dating of 18 samples from Jericho, including six samples of carbonized cereal from the burnt stratum, gave the age of the strata as 1562 BC, with a margin of error of 38 years [3562 ± 38 b2k].^[31]

Early Bronze Ages

The Early Bronze Ages begin about 5300 b2k and end about 4100 b2k. A logboat from Ireland (Inch Abbey, Co. Down) was dendrochronology dated to 4140 b2k.^[9]

A logboat made from alder from Denmark (Verup l) designated K-4098B was radiocarbon dated to 4220 ± 75 b2k.^[9]

A logboat from Ireland (Ballygowan, Co. AmJagh) designated GrN-20550 was radiocarbon dated to 4660 ± 40 b2k.^[9]

Atlantic

Hieroglyphics found at El-Khawy in Egypt show two storks, back to back, with an ibis between them (left), as well as a bull's head (right). Credit: John Darnell, Yale University.{{fairuse}}

A little elephant is shown inside an adult elephant, an indication that the animal is pregnant. Credit: John Darnell, Yale University.{{fairuse}}

The "Atlantic period [is from] 4.6–6 ka [6,000 to 4,600 b2k]."^[23]

"This newly discovered rock art site of El-Khawy preserves some of the earliest — and largest — signs from the formative stages of the hieroglyphic script [such as the back-to-back storks in the image on the right dating back around 5,200 years] and provides evidence for how the ancient Egyptians invented their unique writing system."^[32]

Another "carving, [on the left, shows] a herd of elephants, created sometime between 4000 B.C. and 3500 B.C. One of the adult elephants in the scene was drawn with a little elephant inside its body [in the image on the right] — an incredibly rare way of representing a pregnant female animal."^[32]

The "reign of Djoser in the Old Kingdom started between 2691 and 2625 B.C.E."^[30]

"The last remains of the American ice sheet disappeared about 6000 years ago [6,000 b2k]".^[7]

Beginning with the temperatures, as derivable from Greenland ice core data, it is possible to define an 'Early' or 'Pre-Atlantic' period at around 8040 BC, where the ¹⁸O isotope line remains above 33 ppm in the combined curve after Rasmussen et al. (2006),^[33] which then would end at the well-known 6.2 ka BC (8.2 ka calBP)-cold-event.

"The Atlantic is equivalent to Pollen Zone VII."^[34]

Boreal transition

"In some cores a narrow band of clay interrupts the organic muds, at the horizon of the Boreal Atlantic transition."^[35]

Chalcolithic

The copper age history period began from 6990 b2k.

The Chalcolithic is often referred to as the Copper Age.

The "oldest securely dated evidence of copper making, from 7,000 years ago [6990 b2k], at the archaeological site of Belovode, Serbia."^[36]

The "Scandinavian one 2000 years earlier [8,000 b2k]."^[7]

Neolithic

The base of the Neolithic is approximated to 12,200 b2k. The transition to the Chalcolithic is between 6,500 and 4,000 b2k.

Pre-Boreal transition

The last glaciation appears to have a gradual decline ending about 12,000 b2k. This may have been the end of the Pre-Boreal transition.

"About 9000 years ago the temperature in Greenland culminated at 4°C warmer than today. Since then it has become slowly cooler with only one dramatic change of climate. This happened 8250 years ago [...]. In an otherwise warm period the temperature fell 7°C within a decade, and it took 300 years to re-establish the warm climate. This event has also been demonstrated in European wooden ring series and in European bogs."^[7]

"The Pre-boreal period marks the transition from the cold climate of the Late-glacial to the warmer climate of Post-glacial time. This change is immediately obvious in the field from the nature of the sediments, changing as they do from clays to organic lake muds, showing that at this time a more or less continuous vegetation cover was developing."^[35]

"At the beginning of the Pre-boreal the pollen curves of the herbaceous species have high values, and most of the genera associated with the Late-glacial fiora are still present e.g. Artemisia, Polemomium and Thalictrum. These plants become less abundant throughout the Pre-boreal, and before the beginning of the Boreal their curves have reached low values."^[35]

Mesolithic

Mesolithic artefacts (most Wommersom quartzite) were found during excavation in Stevoort, 2008 (Collection Prehistoric Archeology K.U. Leuven). Credit: Vaneiles.{{free media}}

The Shigir Idol is displayed. Credit: Владислав Фальшивомонетчик.{{free media}}

Two skeletons of women aged between 25 and 35 years, dated between 6740 and 5680 BP, both of whom died a violent death. Found at Téviec, France, in 1938. Credit: Didier Descouens.{{free media}}

The mesolithic period dates from around 13,000 to 8,500 b2k.

By the time of Vere Gordon Childe's work, The Dawn of Europe (1947), which affirms the Mesolithic, sufficient data had been collected to determine that a transitional period between the Paleolithic and the Neolithic was indeed a useful concept.^[37]

The Mesolithic began with the Holocene warm period around 11,660 BP and ended with the introduction of farming, the date of which varied in each geographical region. Regions that experienced greater environmental effects as the last glacial period ended have a much more apparent Mesolithic era, lasting millennia.^[38]

Late Pleistocene

Late Pleistocene spans ca. 11,000-150,000 yr BP.^[39]

Flandrian interglacial

The first part of the Flandrian, known as the Younger Atlantic, was a period of fairly rapid sea level rise,^[40] known as the Flandrian transgression and associated with the melting of the Fenno-Scandian, Scottish, Laurentide and Cordilleran Cordilleran glaciers.

Fjords were formed during the Flandrian transgression when U-shaped glaciated valleys were inundated with water.^[41]

The Flandrian began as the relatively short-lived Younger Dryas climate downturn came to an end. This formed the last gasp of the Devensian glaciation.

Younger Dryas

Percentages of Neogloboquadrina pachyderma are shown with depth and ¹⁴C dates from cores. Credit: Scott J. Lehman & Lloyd D. Keigwin.

The "Alleröd/Younger Dryas transition [occurred] some 11,000 years ago [11,000 b2k]."^[42]

"The Younger Dryas interval during the Last Glacial Termination was an abrupt return to glacial-like conditions punctuating the transition to a warmer, interglacial climate."^[43]

"From former cirque glaciers in western Norway, it is calculated that the summer (1.May to 30.September) temperature dropped 5-6°C during less than two centuries, probably within decades, at the Alleröd/Younger Dryas transition, some 11,000 years ago."^[42]

Allerød Oscillation

The "Allerød Chronozone, 11,800 to 11,000 years ago".^[42]

"During the Allerød Chronozone, 11,800 to 11,000 years ago, western Europe approached the present day environmental and climatic situation, after having suffered the last glacial maximum some 20,000 to 18,000 years ago. However, the climatic deterioration 11,000 years ago led to nearly fully glacial conditions on this continent for some few hundreds of years during the Younger Dryas. This change is completely out of phase with the Milankovitch (orbital) forcing as this is understood today, and therefore its cause is of major interest."^[42]

"Excess ¹⁴C in Cariaco Basin sediments indicates a slowing in thermohaline circulation and heat transport to the North Atlantic at that time, and both marine and terrestrial paleoclimate proxy records around the North Atlantic show a short-lived (<400 yr) cold event (Intra-Allerød cold period) that began ca. 13,350 yr B.P."^[44]

Pleistocene

The Pleistocene dates from 2.588 x 10⁶ to 11,700 b2k.

People appear.

Paleolithic

Cave of Altamira and Paleolithic Cave Art of Northern Spain are shown. Credit: Yvon Fruneau, photographer.

The paleolithic period dates from around 2.6 x 10⁶ b2k to the end of the Pleistocene around 12,000 b2k.

The Paleolithic or Palaeolithic is a period in human prehistory distinguished by the original development of stone tools that covers c. 95% of human technological prehistory.^[45] It extends from the earliest known use of stone tools by hominins c. 3.3 million years ago, to the end of the Pleistocene c. 11,650 cal BP.^[46]

Older Dryas

Comparison of the GRIP ice core with cores from the Cariaco Basin shows the Older Dryas. Credit: Konrad A Hughes, Jonathan T. Overpeck, Larry C. Peterson & Susan Trumbore.

"Older Dryas [...] events [occurred about 13,400 b2k]".^[48]

"The most negative δ ¹⁸O excursions seen in the GRIP record lasted approximately 131 and 21 years for the [inter-Allerød cold period] IACP and [Older Dryas] OD, respectively. The comparable events in the Cariaco basin were of similar duration, 127 and 21 years. In addition to the chronological agreement, there is also considerable similarity in the decade-scale patterns of variability in both records. Given the geographical distance separating central Greenland from the southern Caribbean Sea, the close match of the pattern and duration of decadal events between the two records is striking."^[48]

In the figures on the right, especially b, is a detailed "comparison of δ ¹⁸O from the GRIP ice core²⁴ with changes in a continuous sequence of light-lamina thickness measurements from core PL07-57PC. Both records are constrained by annual chronologies, although neither record is sampled at annual resolution. The interval of comparison includes the inter-Allerød cold period (12.9-13 cal. kyr BP) and Older Dryas (13.4 cal. kyr BP) events (IABP and OD from a). The durations of the two events, measured independently in both records, are very similar, as is the detailed pattern of variability at the decadal timescale."^[48]

Marine Isotope Stage 1

The Earth is currently experiencing an interglacial period (warming) during the present Quaternary Ice Age, identified as the "Marine Isotope Stage 1" (MIS1) in the Holocene epoch (or recently the Anthropocene epoch).

Dansgaard–Oeschger events are considered switches between states of the climate system.^[49]

The Holocene period began around 11,700 years ago and continues to the present.^[50] Identified with the current warm period, known as "Marine Isotope Stage 1", or MIS 1, the Holocene is considered an interglacial period in the Quaternary glaciation or current Ice Age.

Bølling Oscillation

The Greenland ice-core oxygen isotope (δ ¹⁸O) stratigraphy. Credit: Barbara Wohlfarth.

The "intra-Bølling cold period [IBCP is a century-scale cold event and the] Bølling warming [occurs] at 14600 cal [calendar years] BP (12700 ¹⁴C BP)".^[51]

The "Bølling was originally defined as starting from 13000 ¹⁴C BP (calibrated to ~15650 cal BP; Stuiver et al., 1998). [...] independent annual chronology indicate a much later onset of the Bølling (e.g., 14600 cal BP".^[51]

"During the IBCP and perhaps also IACP, δ ¹⁸O values inversely correlate with δ ¹³C, but during the OD δ ¹⁸O shows positive correlation with δ ¹³C, suggesting dry conditions with high evaporation, as well as cold."^[51]

The Bølling interstadial corresponds to GIS 1 as shown in the diagram on the right.^[52]

MIS Boundary 1/2 is at 14 ka.^[53]

Marine Isotope Stage 2

Termination I, also known as the Last Glacial Termination, is the end of Marine isotope stage 2.

Oldest Dryas

"During the Late Weichselian glacial maximum (20-15 ka BP) the overriding of ice streams eventually lead to strong glaciotectonic displacement of Late Pleistocene and pre-Quaternary deposits and to deposition of till."^[54]

"The synchronous and nearly uniform lowering of snowlines in Southern Hemisphere middle-latitude mountains compared with Northern Hemisphere values suggests global cooling of about the same magnitude in both hemispheres at the [Last Glacial Maximum] LGM. When compared with paleoclimate records from the North Atlantic region, the middle-latitude Southern Hemisphere terrestrial data imply interhemispheric symmetry of the structure and timing of the last glacial/interglacial transition. In both regions atmospheric warming pulses are implicated near the beginning of Oldest Dryas time (~14,600 ¹⁴C yr BP) and near the Oldest Dryas/Bølling transition (~12,700-13,000 ¹⁴C yr BP). The second of these warming pulses was coincident with resumption of North Atlantic thermohaline circulation similar to that of the modern mode, with strong formation of Lower North Atlantic Deep Water in the Nordic Seas. In both regions, the maximum Bølling-age warmth was achieved at 12,200-12,500 ¹⁴C yr BP, and was followed by a reversal in climate trend. In the North Atlantic region, and possibly in middle latitudes of the Southern Hemisphere, this reversal culminated in a Younger-Dryas-age cold pulse."^[55]

Meiendorf Interstadial

Temperature curve of late glacial period, from NGRIP greenland ice core oxygen isotope ratio. Credit: Merikanto.{{free media}}

The period spans starting at the far right of the image on the right from Lascaux interstadial to Heinrich event H1, and to Meiendorf/Bölling warm stage, and Alleröd warm stage, to Younger dryas and early holocene.

The Meiendorf Interstadial is typified by a rise in the pollens of dwarf birches (Betula nana), willows (Salix sp.), sandthorns (Hippophae), junipers (Juniperus) and Artemisia.

The beginning of the Meiendorf Interstadial is around 14,700 b2k.

Heinrich event H1

This stadial starts about 17.5 ka, extends to about 15.5 ka and is followed after a brief warming by H1.

Lascaux interstadial

The Lascaux interstadial begins about 21 ka and extends to about 18 ka.

Jylland stade

"After c. 22 ka BP during the Jylland stade (Houmark-Nielsen 1989), Late Weichselian glaciers of the Main Weichselain advance overrode Southeast Denmark from the northeast and later the Young Baltic ice invaded from southeasterly directions. Traces of the Northeast-ice are apparently absent in the Klintholm sections, although large scale glaciotectonic structures and till deposits from this advance are found in Hjelm Bugt and Møns Klint (Aber 1979; Berthelsen 1981, 1986). At Klintholm, the younger phase of glaciotectonic deformation from the southeast and south and deposition of the discordant till (unit 9) were most probably associated with recessional phases of the Young Baltic glaciation. In several cliff sections, well preserved Late Glacial (c. 14-10 ka BP) lacustrine sequences are present (Kolstrup 1982, Heiberg 1991)."^[54]

Laugerie Interstadial

Diagram showings the position of the Lascaux interstadial (marked in red and orange) within the time range 10 to 30 ky BP. Credit: Rudolf Pohl.{{free media}}

The weak interstadial corresponding to GIS 2 occurred about 23.2 kyr B.P.^[52]

The δ18O values from GISP-2 follow the diagram of Wolfgang Weißmüller. The positions of the Dansgaard-Oeschger events DO1 to DO4 and the Heinrich events H1 to H3 are also indicated. DV 3-4 and DV 6-7 are cold events marked by ice wedges in the upper loess of Dolní Veštonice.

Letzteiszeitliches Maximum

This glacial advance begins about 26 ka and ends abruptly at about 23.4 ka.

GIS 3

The stronger GIS 3 interstadial occurred about 27.6 kyr B.P.^[52]

It begins abruptly at 29 ka and ends about 26 ka.

"GIS 3 (start) 25.571 [to] GIS 3 (end) 25.337 ka BP".^[56]

Stadial

Heinrich Event 3 (H3) "occurs at 26.74 ka BP, coincident with the start of the transition into GIS 4."^[56]

MIS Boundary 2/3 is at 29 ka.^[53]

"Stadial duration 0.768 ka".^[56]

Møn interstadial

The Møn interstadial corresponds to GIS 4.^[52]

Klintholm advance

This advance occurred after the Møn and ended with GIS 6.^[52]

"Stadial duration 2.899 ka".^[56]

GIS 5

GIS 5 interstadial occurred during the Klintholm advance about 33.5 kyr B.P.^[52]

"GIS 5 (start) 30.013 [to] GIS 5 (end) 29.526 ka BP".^[56]

Stadial

Stadial duration 0.836 ka""^[56]

Ålesund Interstadial

The Ålesund interstadial began with GIS 6 and ended after GIS 8.^[52]

"GIS 6 (start) 31.218 [to] GIS 6 (end) 30.849 ka BP".^[56]

Stadial

"Stadial duration 0.932 ka".^[56]

GIS 7 interstadial

"GIS 7 (start) 32.896 [to] GIS 7 (end) 32.15 ka BP".^[56]

Stadial

"Stadial duration 0.642 ka".^[56]

Huneborg interstadial

The Huneborg interstadial is a Greenland interstadial dating 36.5-38.5 kyr B.P. GIS 8.^[52]

The Denekamp interstadial corresponds to the Huneborg interstadial.

"GIS 8 (start) 35.716 [to] GIS 8 (end) 33.977 ka BP".^[56]

Heinrich Event 4

Heinrich Event 4 "33-39.93 ka BP".^[56]

Hengelo interstadial

The Hengelo interstadial [is] > 35 ka BP".^[54]

The "Hengelo Interstadial [is] (38–36 ka ago)."^[57]

"An evolution with the coldest phases (coarsest grains) between 27,000 and 10,000 years B.P., 52,000 and 34,000 years B.P., and 76,000 and 60,000 years B.P. and relatively warmer intervals (finer grain size) in between is obvious. Apparently, they reflect a 21,000-year periodicity. This trend is superposed by much shorter oscillations of a duration of one to a few thousand years. Their duration is similar to the Dansgaard-Oeschger oscillations in the ice-core records. Some well-defined stadials and interstadials from the terrestrial records show also such a duration: for instance, the Hengelo interstadial around 37-38,500 ¹⁴C years B.P. (Zagwijn, 1974; Kasse et al., 1995) and the preceding Hasselo stadial at approximately 40-38,500 ¹⁴C years B.P. (Van Huissteden, 1990)."^[58]

Hasselo stadial

The polarity reversal some 41,000 years ago was a global event. Credit: Norbert Nowaczyk and Helge Arz, Helmholtz Centre Potsdam - GFZ German Research Centre for Geosciences.

The "Hasselo stadial [is] at approximately 40-38,500 ¹⁴C years B.P. (Van Huissteden, 1990)."^[58]

The "Hasselo Stadial [is a glacial advance] (44–39 ka ago)".^[57]

"One of two strongly rounded fragments of the mammoth maxilla from the Shapka Quarry in the southern Leningrad region was recently dated at 38450 + 400/–300 years (GrA-39 116) and rhinoceros remains (spoke bone), back to 38360 + 300/–270 years ago (GrA-38 819) [7]. The maxilla fragments occurred in sediments of the Leningrad Interstadial, which correspond to the transition between the Hasselo Stadial (44–39 ka ago) and the Hengelo Interstadial (38–36 ka ago)."^[57]

The Hasselo stadial corresponds to the Skjonghelleren stadial in Norway but to the Sejrø interstadial in Denmark.^[52]

"Paleomagnetic samples were obtained from cores taken during the drilling of a research well along Coyote Creek in San Jose, California, in order to use the geomagnetic field behavior recorded in those samples to provide age constraints for the sediment encountered. The well reached a depth of 308 meters and material apparently was deposited largely (entirely?) during the Brunhes Normal Polarity Chron, which lasted from 780 ka to the present time."^[59]

"Three episodes of anomalous magnetic inclinations were recorded in parts of the sedimentary sequence; the uppermost two we correlate to the Mono Lake (~30 ka) geomagnetic excursion and 6 cm lower, tentatively to the Laschamp (~45 ka) excursion."^[59]

"Some 41,000 years ago, a complete and rapid reversal of the geomagnetic field occured. Magnetic studies on sediment cores from the Black Sea show that during this period, during the last ice age, a compass at the Black Sea would have pointed to the south instead of north."^[60]

"[A]dditional data from other studies in the North Atlantic, the South Pacific and Hawaii, prove that this polarity reversal was a global event."^[60]

"The field geometry of reversed polarity, with field lines pointing into the opposite direction when compared to today's configuration, lasted for only about 440 years, and it was associated with a field strength that was only one quarter of today's field."^[60]

"The actual polarity changes lasted only 250 years. In terms of geological time scales, that is very fast."^[60]

"During this period, the field was even weaker, with only 5% of today's field strength. As a consequence, Earth nearly completely lost its protection shield against hard cosmic rays, leading to a significantly increased radiation exposure."^[60]

"This is documented by peaks of radioactive beryllium (¹⁰Be) in ice cores from this time, recovered from the Greenland ice sheet. ¹⁰Be as well as radioactive carbon (¹⁴C) is caused by the collision of high-energy protons from space with atoms of the atmosphere."^[60]

"The polarity reversal [...] has already been known for 45 years. It was first discovered after the analysis of the magnetisation of several lava flows near the village Laschamp near Clermont-Ferrand in the Massif Central, which differed significantly from today's direction of the geomagnetic field. Since then, this geomagnetic feature is known as the 'Laschamp event'."^[60]

The "new data from the Black Sea give a complete image of geomagnetic field variability at a high temporal resolution."^[60]

Moershoofd interstadial

These three maps show a succession of artefacts in western and southern Europe. Credit: Catherine Brahic.

The Moershoofd interstadial has a ¹⁴C date of 44-46 kyr B.P. and corresponds to GIS 12 at 45-47 kyr B.P.^[52]

Marine Isotope Stage 3

Inca Huasi was a paleolake in the Andes named by a research team in 2006.^[61]

It existed about 46,000 years ago in the Salar de Uyuni basin.^[61] Water levels during this episode rose by about 10 metres (33 ft). Overall, this lake cycle was short and not deep,^[61] with water levels reaching a height of 3,670 metres (12,040 ft). The lake would have had a surface of 21,000 square kilometres (8,100 sq mi).^[62] Most water was contributed to it by the Uyuni-Coipasa drainage basin, with only minimal contributions from Lake Titicaca.^[63] Changes in the South American monsoon may have triggered its formation.^[64]

Radiocarbon dates on tufa which formed in Lake Inca Huasi were dated at 45,760 ± 440 years ago.^[61] Uranium-thorium dating has yielded ages between 45,760 and 47,160 years.^[61] Overall the lake existed between 46,000 and 47,000 years ago.^[62] The Inca Huasi cycle coincides with the marine isotope stage 3,^[65] the formation of a deep lake in the Laguna Pozuelos basin and the expansion of glaciers in several parts of South America.^[66]

This lake cycle took part during a glacial epoch, along with the Sajsi lake cycles.^[61] A more humid climate in northeastern Argentina and elsewhere in subtropical South America has been linked to the Inca Huasi phase.^[64] However, rainfall might not have increased by much on the Altiplano during the Inca Huasi cycle.^[62]

Other paleolakes are Coipasa, Ouki, Minchin, Sajsi, Salinas and Tauca.^[61] Research made in 2006 attributed the "Lake Minchin" to this lake phase.^[64]

In archaeology, a bout-coupé is a type of handaxe that constituted part of the Neanderthal Mousterian industry of the Middle Palaeolithic. The handaxes are bifacially-worked and in the shape of a rounded triangle. They are only found in Britain in the Marine Isotope Stage 3 (MIS 3) interglacial between 59,000 and 41,000 years BP, and are therefore considered a unique diagnostic variant.^[67][68]

Lynford Quarry is the location of a well-preserved in-situ Middle Palaeolithic open-air site near Mundford, Norfolk.^[69]

The site, which dates to approximately 60,000 years ago, is believed to show evidence of hunting by Neanderthals (Homo neanderthalensis). The finds include the in-situ remains of at least nine woolly mammoths (Mammuthus primigenius), associated with Mousterian stone tools and debitage. The artefactual, faunal and environmental evidence were sealed within a Middle Devensian palaeochannel with a dark organic fill. Well preserved in-situ sites of the time are exceedingly rare in Europe and very unusual within a British context.^[70]

The site also produced rhinoceros teeth, antlers, as well as other faunal evidence. The stone tools on the site numbered 600, made up of individual artefacts or waste flakes. Particularly interesting were the 44 hand axes of sub-triangular or ovate form.^[71]

The site was dated to Marine Isotope Stage 3 using Optically Stimulated Luminescence dating of the sand from the two layers of deposits within the channel.^[71]

Eruptions occurred at Monte Burney (a volcano in southern Chile, part of its Austral Volcanic Zone which consists of six volcanoes with activity during the Quaternary) during the Pleistocene. Two eruptions around 49,000 ± 500 and 48,000 ± 500 years before present deposited tephra in Laguna Potrok Aike,^[72] a lake approximately 300 kilometres (190 mi) east of Monte Burney;^[73] there they reach thicknesses of 48 centimetres (19 in) and 8 centimetres (3.1 in) respectively.^[72] Other Pleistocene eruptions are recorded there at 26,200 and 31,000 years ago,^[74] with additional eruptions having occurred during marine isotope stage 3.^[74]

Glinde interstadial

The Glinde interstadial has a ¹⁴C date of 48-50 kyr B.P. and corresponds to GIS ?13/14 with a GIS age of 49-54.5 kyr B.P.^[52]

Ebersdorf Stadial

This map of Australia combines genetic and archaeological data to show the movements of Aboriginal populations going back tens of thousands of years. Credit: Alan Cooper and Ray Tobler, University of Adelaide.{{fairuse}}

"Genetics suggests Neanderthal numbers dropped sharply around 50,000 years ago. This coincides with a sudden cold snap, hinting climate struck the first blow."^[75]

This corresponds to the Skjonghelleren Glaciation of Scandinavia where ice crosses the North Sea between 50-40 ka BP.

"The first humans probably reached Australia around 50,000 years ago, which is the age of the oldest human skeletons and tools found."^[76]

All "the Aborigines likely descend from a single population, which reached the Australian continent 50,000 years ago. Populations then spread rapidly – within 1,500 to 2,000 years – around the east and west coasts of Australia, meeting somewhere in South Australia. Over the following millennia, the population groups remained practically isolated."^[76]

"Australia 50,000 years ago was part of the same landmass as New Guinea. So that the first Aborigines could have reached New Guinea by way of South East Asia and then have gone farther to Australia. There, they settled in groups over the whole continent."^[76]

Many "groups of Aborigines used similar tools and shared a similar language. If humans did not move, how could tools and languages?"^[77]

Oerel interstadial

The Oerel interstadial has a ¹⁴C date of 53-58 kyr B.P. and corresponds to GIS 15/16 with a GIS age of 56-59 kyr B.P.^[52]

MIS Boundary 3/4 is at 57 ka.^[53]

Karmøy stadial

The Karmøy stadial begins in the high mountains of Norway about 58 kyr B.P. and expands to the outer coast by 60 kyr B.P.^[52]

The Schalkholz Stadial in North Germany is equivalent.

Odderade interstadial

The Odderade interstadial has a ¹⁴C date of 61-72 kyr B.P. and corresponds to GIS 21.^[52]

MIS Boundary 4/5 is at 71 ka.^[53]

Marine Isotope Stage 4

The glacial episode of Marine Isotope Stage 4, about 57-71,000 years ago, resulted in cooler and drier climatic conditions and the expansion of grassland vegetation. Credit: ROCEEH.{{free media}}

Neanderthal skull, Museum d'Anthropologie, campus universitaire d'Irchel, Université de Zurich (Suisse), is imaged. Credit: Guerin Nicolas.{{fairuse}}

"During the Middle Stone Age of Southern Africa, technological and behavioral innovations led to significant changes in the lifeways of modern humans. The glacial episode of Marine Isotope Stage 4, about 57-71,000 years ago, resulted in cooler and drier climatic conditions and the expansion of grassland vegetation. Sea level dropped by as much as 80 meters below its current level. During this period the cultural phase known as the Howieson’s Poort appeared across much of Southern Africa, peaking at about 60-65,000 years ago, and then disappeared. The lithic industry of the Howieson’s Poort is exemplified by changes in technology, such as the use of the punch technique, an increase in the selection of fine-grained silcrete, and the predominance of retouched pieces including backed tools, segments, scrapers and points. Segments are the type fossil of the Howieson’s Poort and represent multi-purpose armatures that were hafted onto wooden spear shafts. The standardized design and refined style of segments convey information about the behavior of their makers and provide insight about group identity. Increasing use of ochre, the presence of engraved ostrich eggshells, and a bone tool industry are associated with these stone artifacts. Also evident is an intensified use of space. Taken together, these behaviors suggest that the Howieson’s Poort represents a clear marker of modern human culture."^[78]

"Using stone tool residue analysis with supporting information from zooarchaeology, we provide evidence that at the Abri du Maras, Ardèche, France, Neanderthals [a skull is imaged on the left from Abri du Maras] were behaviorally flexible at the beginning of MIS 4. Here, Neanderthals exploited a wide range of resources including large mammals, fish, ducks, raptors, rabbits, mushrooms, plants, and wood. Twisted fibers on stone tools provide evidence of making string or cordage."^[79]

Wisconsinian glacial

Wisconsinian glacial began at 80,000 yr BP.^[39]

Rederstall Stadial

MIS Boundary 5.3 is at 96 ka.^[53]

MIS Boundary 5.2 (peak) is at 87 ka.^[53]

MIS Boundary 5.1 (peak) is at 82 ka.^[53]

Brørup interstadial

The "Brørup interstade [is about] 100 ka BP".^[54] It corresponds to GIS 23/24.^[52]

MIS Boundary 5.4 (peak) is at 109 ka.^[53]

Herning Stadial

MIS Boundary 5.5 (peak) is at 123 ka.^[53]

Eemian interglacial

The "controversially split Eemian period, the predecessor of our own warm period about 125,000 years ago."^[7]

"The Eem interglaciation […] lasted from 131 to 117 kyr B.P."^[7]

Late Pleistocene

Late Pleistocene spans ca. 11,000-150,000 yr BP.^[39]

MIS Boundary 5/6 is at 130 ka.^[53]

Sangamon Episode interglacial

"OSL dates also suggest that last interglacial (MIS 5; Sangamon Ep.) fluvial deposits are preserved locally."^[80]

Age "assignment of Sangamonian (sense alto = 80,000-ca. 220,000 yr BP) [is] to Illinoian (ca. 220,000-430,000 yr BP)".^[39]

MIS Boundary 6/7 is at 191 ka.^[53]

Middle Pleistocene

Middle Pleistocene spans ca. 150,000-730,000 yr BP.^[39]

Illinois Episode glaciation

"Ages of sediments immediately beneath the oldest till (Kellerville Mbr.) in the bedrock valley average 160 ka and provide direct confirmation that Illinois Episode (IE) glaciation began in its type area during marine isotope stage (MIS) 6. The oldest deposits found are 190 ka fluvial sands on bedrock in the deepest part of the valley. These correlate to earliest MIS 6. We now correlate the lowest deposits to the IE (Pearl Fm.)."^[80]

The "last two glacial cycles [span] MIS 6 through 2".^[80]

"Illinoian [is] (ca. 220,000-430,000 yr BP)".^[39]

MIS Boundary 10/11 is at 374 ka.^[53]

MIS Boundary 9/10 is at 337 ka.^[53]

MIS Boundary 8/9 is at 300 ka.^[53]

MIS Boundary 7/8 is at 243 ka.^[53]

Yarmouthian interglacial

"Clay deposition in the Piauí River floodplain around 436 ± 51.5 ka occurred during a warmer period of the [Yarmouthian interglaciation] Aftonian interglaciation, corresponding to isotope stage 12 (Ericson and Wollin, 1968)."^[81]

"The extinctions and earliest known first occurrences of the 26 extant and 8 extinct cyst taxa in the three samples (with a minimum 430,000 yr BP Yarmouthian age) corroborate a likely assemblages with a maximum age of Illinoian (ca. 220,000-430,000 yr BP) in Unit I."^[39]

Yarmouthian spans 420,000-500,000 yr BP.^[39]

MIS Boundary 12/13 is at 478 ka.^[53]

MIS Boundary 11/12 is at 424 ka.^[53]

Kansan glacial

Kansan glacial spans 500,000-600,000 yr BP.^[39]

MIS Boundary 14/15 is at 563 ka.^[53]

MIS Boundary 13/14 is at 533 ka.^[53]

Aftonian interglacial

Examples of pre–Illinoian stratigraphic sections are shown. Credit: M. Roy, P.U. Clark, R.W. Barendregt, J.R. Glasmann, and R.J. Enkin.{{fairuse}}

Aftonian interglacial spans ca. 600,000-650,000 yr BP.^[39]

"N tills [...] show the greatest amount of feldspar and carbonate minerals in the silt fraction. This group includes at least one till unit overlain by the 0.6 Ma Lava Creek ash, thus suggesting that some of these units were deposited between 0.8 and 0.6 Ma, but also later, as indicated by two sites with a till overlying the 0.6 Ma ash (Boellstorff, 1973). The N till group is considered to include the A1, A2, and A3 tills of Boellstorff (1973, 1978b)."^[82]

Lava Creek B ash is dated at 602 ka.^[82]

MIS Boundary 15/16 is at 621 ka.^[53]

The Yellowstone Lava Creek B ash is dated at 639 ± 2 ka ka.^[83]

"The Lava Creek B ash bed (0.64 Ma) originated from one of several Yellowstone Plateau plinian eruptions that produced extensive ashfall over much of the west-central United States (Izett and Wilcox, 1982)."^[83]

"The second, and geochemically analyzed, occurrence of Lava Creek B ash is in Kelso Gulch, along sloping hillsides slightly above the valley floor (Fig. 2). The tephra layer intermittently follows the contour of the hillslope at an elevation of 1,591 m. It is variably cemented with calcite and up to 5 cm thick. At this locality, geochemical confirmation of the Lava Creek B ash by co-author Wan (Table 1) comes from sample K06CO3, collected from an indurated, ca. 5-cm-thick ash bed exposed on a hillside (Fig. 2). This ash bed is thinly mantled by slope-wash."^[83]

"Processing, petrographic analysis, and geochemical fingerprinting of tephra sample K06CO3 and its identification as the Lava Creek B ash was performed at the USGS Tephrochronology Laboratory and the Electron Microprobe Laboratory in Menlo Park, California."^[83]

"The age of the [stag moose Cervalces] roosevelti type specimen is pre-Wisconsin (Aftonian)".^[84]

"Examples of pre–Illinoian sections [are in the images on the right]. (A) Two till units with paleosols separated by nonglacial silt and clay unit at site 19 (blow-up of units to left). (B) Lava Creek B ash (0.602 Ma) cropping out near site 4. (C) Two-till unit sequence capped by loess deposits at site 15. Lower till is truncated by sand and gravel unit whereas upper till is affected by paleosol development. Sandy diamicton is present between lower till and bedrock."^[82]

Nebraskan glacial

Nebraskan glacial spans ca. 650,000-1,000,000 yr BP.^[39]

The magnetic field reversal to the present geomagnetic poles (Brunhes chron) occurred at 780,000 yr BP.

"The R1-till group includes two till units that overlie the 1.3 Ma Mesa Falls ash, thus indicating at least two glaciations between 1.3 Ma and 0.8 Ma."^[82]

The magnetic field reversal to the opposite geomagnetic poles (subchron) occurred at 900,000 yr BP.

MIS Boundary 27/28 is at 982 ka.^[53]

MIS Boundary 26/27 is at 970 ka.^[53]

MIS Boundary 25/26 is at 959 ka.^[53]

MIS Boundary 24/25 is at 936 ka.^[53]

MIS Boundary 23/24 is at 917 ka.^[53]

MIS Boundary 22/23 is at 900 ka.^[53]

MIS Boundary 21/22 is at 866 ka.^[53]

MIS Boundary 20/21 is at 814 ka.^[53]

MIS Boundary 19/20 is at 790 ka.^[53]

MIS Boundary 18/19 is at 761 ka.^[53]

MIS Boundary 17/18 is at 712 ka.^[53]

MIS Boundary 16/17 is at 676 ka.^[53]

Early Pleistocene

Early Pleistocene spans ca. 730,000-1,600,000 yr BP.^[39]

Mesa Falls ash is dated at 1293 ka.^[82]

Calabrian

Lithologic and magnetostratigraphic correlations are for the Calabrian GSSP. Credit: Maria Bianca Cita, Philip L. Gibbard, Martin J. Head, and the ICS Subcommission on Quaternary Stratigraphy.

The Vrica section and surrounding area includes specifically the GSSP of the Calabrian Stage fixed at the top of layer ‘e’. Credit: Maria Bianca Cita, et al.

The magnetic field reversal to the present geomagnetic poles (Jaramillo subchron) occurred at 1,060,000 yr BP.

The magnetic field reversal to the opposite, back to the present, then opposite geomagnetic poles (Cobb Mountain subchron) occurred at 1,190,000 yr BP.

The magnetic field reversal to the opposite geomagnetic poles (Olduvai subchron) occurred at 1,780,000 yr BP.

"The [Calabrian] GSSP occurs at the base of the marine claystone conformably overlying sapropelic bed ‘e’ within Segment B in the Vrica section. This lithological level represents the primary marker for the recognition of the boundary, and is assigned an astronomical age of 1.80 Ma on the basis of sapropel calibration."^[85]

MIS Boundary 63/64 is at 1782 ka.^[53]

MIS Boundary 62/63 is at 1758 ka.^[53]

MIS Boundary 61/62 is at 1743 ka.^[53]

MIS Boundary 60/61 is at 1715 ka.^[53]

MIS Boundary 59/60 is at 1697.5 ka.^[53]

MIS Boundary 58/59 is at 1670 ka.^[53]

MIS Boundary 57/58 is at 1642.5 ka.^[53]

MIS Boundary 56/57 is at 1628.5 ka.^[53]

"The boundary falls between the highest occurrence of Discoaster brouweri (below) and the lowest common occurrence of left-coiling Neogloboquadrina pachyderma (above), and below the lowest occurrences of medium-sized Gephyrocapsa (including G. oceanica) and Globigerinoides tenellus."^[85]

In the image on the right, the Vrica section includes specifically the GSSP of the Calabrian Stage fixed at the top of layer 'e'.

Gelasian

The base of the marly layer overlying sapropel MPRS 250, located at 62 m in the Monte San Nicola section, is the defined base of the Gelasian Stage. Credit: D. Rio, R. Sprovieri, D. Castradori, and E. Di Stefano.

Some number of N tills occurred during the Olduvai subchron.^[82]

The magnetic field reversal to the present geomagnetic poles (Olduvai subchron) occurred at 2,000,000 yr BP.

The oldest till group, R2 tills, consists of till units with a reversed polarity and >77% of sedimentary clasts. Low amounts of expandable clays, substantial amounts of kaolinite, and the absence of chlorite characterize the clay mineralogy of R2 tills. The mineralogy of the silt fraction of R2 tills is rich in quartz and depleted in calcite, dolomite, and feldspar. This till group includes a till unit that underlies the 2.0-Ma Huckleberry Ridge ash, thus indicating deposition sometime between ~2.5 Ma (onset of Northern Hemisphere glaciations) (Mix et al., 1995) and 2.0 Ma.^[82]

The magnetic field reversal to the present geomagnetic poles (Reunion subchron) and back occurred at 2,080,000 yr BP.

The magnetic field reversal to the present geomagnetic poles (Reunion subchron) and back occurred at 2,140,000 yr BP.

"The base of the Quaternary System [shown in the image on the right] is defined by the Global Stratotype Section and Point (GSSP) of the Gelasian Stage at Monte San Nicola in Sicily, Italy, currently dated at 2.58 Ma."^[86]

"The astrochronological age of sapropel MPRS 250 (mid-point), corresponding to precessional cycle 250 from the present, is 2.588 Ma (Lourens et al., 1996), which can be assumed as the age of the boundary."^[87]

MIS Boundary 102/103 is at 2575 ka.^[53]

MIS Boundary 101/102 is at 2554 ka.^[53]

MIS Boundary 100/101 is at 2540 ka.^[53]

MIS Boundary 99/100 is at 2510 ka.^[53]

MIS Boundary 98/99 is at 2494 ka.^[53]

MIS Boundary 97/98 is at 2477 ka.^[53]

MIS Boundary 96/97 is at 2452 ka.^[53]

MIS Boundary 95/96 is at 2427 ka.^[53]

MIS Boundary 94/95 is at 2407 ka.^[53]

MIS Boundary 93/94 is at 2387 ka.^[53]

MIS Boundary 92/93 is at 2373 ka.^[53]

MIS Boundary 91/92 is at 2350 ka.^[53]

MIS Boundary 90/91 is at 2333 ka.^[53]

MIS Boundary 89/90 is at 2309 ka.^[53]

MIS Boundary 88/89 is at 2291 ka.^[53]

MIS Boundary 87/88 is at 2273 ka.^[53]

MIS Boundary 86/87 is at 2250 ka.^[53]

MIS Boundary 85/86 is at 2236 ka.^[53]

MIS Boundary 84/85 is at 2207.5 ka.^[53]

MIS Boundary 83/84 is at 2192 ka.^[53]

MIS Boundary 82/83 is at 2168 ka.^[53]

MIS Boundary 81/82 is at 2146 ka.^[53]

MIS Boundary 80/81 is at 2125 ka.^[53]

MIS Boundary 79/80 is at 2103 ka.^[53]

MIS Boundary 78/79 is at 2088 ka.^[53]

MIS Boundary 77/78 is at 2043 ka.^[53]

MIS Boundary 76/77 is at 2017 ka.^[53]

Huckleberry Ridge ash is dated at 2003 ka.^[82]

MIS Boundary 75/76 is at 1990 ka.^[53]

MIS Boundary 74/75 is at 1965 ka.^[53]

MIS Boundary 73/74 is at 1941 ka.^[53]

MIS Boundary 72/73 is at 1915 ka.^[53]

MIS Boundary 71/72 is at 1898 ka.^[53]

MIS Boundary 70/71 is at 1875 ka.^[53]

MIS Boundary 69/70 is at 1859.5 ka.^[53]

MIS Boundary 68/69 is at 1849 ka.^[53]

MIS Boundary 67/68 is at 1832.5 ka.^[53]

MIS Boundary 66/67 is at 1826 ka.^[53]

MIS Boundary 65/66 is at 1816 ka.^[53]

MIS Boundary 64/65 is at 1802.5 ka.^[53]

Tertiary

The Tertiary Period extends from 65.5 ± 0.3 to 2.588 x 10⁶ b2k.

Neogene

The Neogene dates from 23.03 x 10⁶ to 2.58 x 10⁶ b2k.

Pliocene

The Pliocene ranges from 5.332 x 10⁶ to 2.588 x 10⁶ b2k.

"All of Pliocene time, without a gap, is physically represented in the three stages of which it is composed, in a single demonstrably uninterrupted sequence of highly fossiliferous Upper Cenozoic deep-water strata on the southern coast of Sicily. From bottom to top, the Pliocene consists of the Lower Pliocene Zanclean Stage, with a boundary-stratotype at Eraclea Minoa and a unit-stratotype at Capo Rossello; the Middle Pliocene Piacenzian Stage, defined at Punta Piccola (Castradori et al., 1998); and the Upper Pliocene Gelasian Stage, defined at Monte San Nicola near Gela (Rio et al., 1994, 1998) [...]."^[88]

"The base of the Quaternary System is defined by the Global Stratotype Section and Point (GSSP) of the Gelasian Stage at Monte San Nicola in Sicily, Italy, currently dated at 2.58 Ma."^[86]

Piacenzian

Chronology of the Rossello composite section is based on the correlation of small-scale carbonate cycle patterns to precession and insolation curves. Credit: D. Castradori, D. Rio, F. J. Hilgen, and L. J. Lourens.

The magnetic field reversal to the present geomagnetic poles (Matuyama chron) occurred at 2,590,000 yr BP.

MIS Boundary MG12/Gi1 is at 3592 ka.^[53]

MIS Boundary MG11/MG12 is at 3578 ka.^[53]

MIS Boundary MG10/MG11 is at 3566 ka.^[53]

MIS Boundary MG9/MG10 is at 3546 ka.^[53]

MIS Boundary MG8/MG9 is at 3532 ka.^[53]

MIS Boundary MG7/MG8 is at 3517 ka.^[53]

MIS Boundary MG6/MG7 is at 3471 ka.^[53]

MIS Boundary MG5/MG6 is at 3444 ka.^[53]

MIS Boundary MG4/MG5 is at 3387 ka.^[53]

MIS Boundary MG3/MG4 is at 3372 ka.^[53]

MIS Boundary MG2/MG3 is at 3347 ka.^[53]

MIS Boundary MG1/MG2 is at 3332 ka.^[53]

MIS Boundary M2/MG1 is at 3312 ka.^[53]

MIS Boundary M1/M2 is at 3264 ka.^[53]

MIS Boundary KM6/M1 is at 3238 ka.^[53]

MIS Boundary KM5/KM6 is at 3212 ka.^[53]

MIS Boundary KM4/KM5 is at 3184 ka.^[53]

MIS Boundary KM3/KM4 is at 3167 ka.^[53]

MIS Boundary KM2/KM3 is at 3150 ka.^[53]

MIS Boundary KM1/KM2 is at 3119 ka.^[53]

MIS Boundary K2/KM1 is at 3097 ka.^[53]

MIS Boundary K1/K2 is at 3087 ka.^[53]

MIS Boundary G22/K1 is at 3055 ka.^[53]

MIS Boundary G21/G22 is at 3039 ka.^[53]

MIS Boundary G20/6G21 is at 3025 ka.^[53]

MIS Boundary G19/G20 is at 2999 ka.^[53]

MIS Boundary G18/G19 is at 2982.5 ka.^[53]

MIS Boundary G17/G18 is at 2966 ka.^[53]

MIS Boundary G16/G17 is at 2937 ka.^[53]

MIS Boundary G15/G16 is at 2913 ka.^[53]

MIS Boundary G14/G15 is at 2893 ka.^[53]

MIS Boundary G13/G14 is at 2876 ka.^[53]

MIS Boundary G12/G13 is at 2858 ka.^[53]

MIS Boundary G11/G12 is at 2838 ka.^[53]

MIS Boundary G10/G11 is at 2820 ka.^[53]

MIS Boundary G9/G10 is at 2798 ka.^[53]

MIS Boundary G8/G9 is at 2777 ka.^[53]

MIS Boundary G7/G8 is at 2759 ka.^[53]

MIS Boundary G6/G7 is at 2730 ka.^[53]

MIS Boundary G5/G6 is at 2704 ka.^[53]

MIS Boundary G4/G5 is at 2690 ka.^[53]

MIS Boundary G3/G4 is at 2681 ka.^[53]

MIS Boundary G2/G3 is at 2652 ka.^[53]

MIS Boundary G1/G2 is at 2638 ka.^[53]

MIS Boundary 104/G1 is at 2614 ka.^[53]

MIS Boundary 103/105 is at 2595 ka.^[53]

"The base of the beige marl bed of the small-scale carbonate cycle 77 (sensu Hilgen, 1991b) is the approved base of the Piacenzian Stage (that is the Lower Pliocene-Middle Pliocene boundary). It corresponds to precessional excursion 347 as numbered from the present with an astrochronological age estimate of 3.600 Ma (Lourens et al., 1996a)."^[89]

Zanclean

A view of the Eraclea Minoa section has the GSSP of the Zanclean Stage and of the Pliocene Series. Credit: John A. Van Couvering, Davide Castradori, Maria Bianca Cita, Frederik J. Hilgen, and Domenico Rio.

"The boundary-stratotype of the stage is located in the Eraclea Minoa section on the southern coast of Sicily (Italy), at the base of the Trubi Formation. The age of the Zanclean and Pliocene GSSP at the base of the stage is 5.33 Ma in the orbitally calibrated time scale, and lies within the lowermost reversed episode of the Gilbert Chron (C3n.4r), below the Thvera normal subchron."^[88]

In the chronostratigraphic correlation in the Piacenzian section, the base of the Zanclean is marked as the '0' point.

MIS Boundary TG5/TG6 is at 5315 ka.^[53]

MIS Boundary TG4/TG5 is at 5301 ka.^[53]

MIS Boundary TG3/TG4 is at 5289 ka.^[53]

MIS Boundary TG2/TG3 is at 5266 ka.^[53]

MIS Boundary TG1/TG2 is at 5241 ka.^[53]

MIS Boundary T8/TG1 is at 5188 ka.^[53]

MIS Boundary T7/T8 is at 5165 ka.^[53]

MIS Boundary T6/T7 is at 5116 ka.^[53]

MIS Boundary T5/T6 is at 5094 ka.^[53]

MIS Boundary T4/T5 is at 5070 ka.^[53]

MIS Boundary T3/T4 is at 5038 ka.^[53]

MIS Boundary T2/T3 is at 5016 ka.^[53]

MIS Boundary T1/T2 is at 5002 ka.^[53]

MIS Boundary ST4/T1 is at 4985 ka.^[53]

MIS Boundary ST3/ST4 is at 4976 ka.^[53]

MIS Boundary ST2/ST3 is at 4952.5 ka.^[53]

MIS Boundary ST1/ST2 is at 4931 ka.^[53]

MIS Boundary Si6/ST1 is at 4904 ka.^[53]

MIS Boundary Si5/Si6 is at 4883 ka.^[53]

MIS Boundary Si4/Si5 is at 4860 ka.^[53]

MIS Boundary Si3/Si4 is at 4840 ka.^[53]

MIS Boundary Si2/Si3 is at 4821 ka.^[53]

MIS Boundary Si1/Si2 is at 4807 ka.^[53]

MIS Boundary NS6/Si1 is at 4778 ka.^[53]

MIS Boundary NS5/NS6 is at 4766 ka.^[53]

MIS Boundary NS4/NS5 is at 4737 ka.^[53]

MIS Boundary NS3/NS4 is at 4722.5 ka.^[53]

MIS Boundary NS2/NS3 is at 4702.5 ka.^[53]

MIS Boundary NS1/NS2 is at 4684 ka.^[53]

MIS Boundary N10/NS1 is at 4658 ka.^[53]

MIS Boundary N9/N10 is at 4648 ka.^[53]

MIS Boundary N8/N9 is at 4622 ka.^[53]

MIS Boundary N7/N8 is at 4603 ka.^[53]

MIS Boundary N6/N7 is at 45887 ka.^[53]

MIS Boundary N5/N6 is at 4570 ka.^[53]

MIS Boundary N4/N5 is at 4538 ka.^[53]

MIS Boundary N3/N4 is at 4523 ka.^[53]

MIS Boundary N2/N3 is at 4508 ka.^[53]

MIS Boundary N1/N2 is at 4487 ka.^[53]

MIS Boundary CN8/N1 is at 4457 ka.^[53]

MIS Boundary CN7/CN8 is at 4446 ka.^[53]

MIS Boundary CN6/CN7 is at 4420 ka.^[53]

MIS Boundary CN5/CN6 is at 4395 ka.^[53]

MIS Boundary CN4/CN5 is at 4371 ka.^[53]

MIS Boundary CN3/CN4 is at 4356 ka.^[53]

MIS Boundary CN2/CN3 is at 4335 ka.^[53]

MIS Boundary CN1/CN2 is at 4327 ka.^[53]

MIS Boundary Co4/CN1 is at 4303 ka.^[53]

MIS Boundary Co3/Co4 is at 4286 ka.^[53]

MIS Boundary Co2/Co3 is at 4259 ka.^[53]

MIS Boundary Co1/Co2 is at 4232 ka.^[53]

MIS Boundary Gi28/Co1 is at 4211 ka.^[53]

MIS Boundary Gi27/Gi28 is at 4192 ka.^[53]

MIS Boundary Gi26/Gi27 is at 4175 ka.^[53]

MIS Boundary Gi25/Gi26 is at 4146 ka.^[53]

MIS Boundary Gi24/Gi25 is at 4098 ka.^[53]

MIS Boundary Gi23/Gi24 is at 4085 ka.^[53]

MIS Boundary Gi22/Gi23 is at 4048 ka.^[53]

MIS Boundary Gi21/Gi22 is at 4029 ka.^[53]

MIS Boundary Gi20/Gi21 is at 4007 ka.^[53]

MIS Boundary Gi19/Gi20 is at 3978 ka.^[53]

MIS Boundary Gi18/Gi19 is at 3952 ka.^[53]

MIS Boundary Gi17/Gi18 is at 3939 ka.^[53]

MIS Boundary Gi16/Gi17 is at 3923 ka.^[53]

MIS Boundary Gi15/Gi16 is at 3912 ka.^[53]

MIS Boundary Gi14/Gi15 is at 3879 ka.^[53]

MIS Boundary Gi13/Gi14 is at 3862 ka.^[53]

MIS Boundary Gi12/Gi13 is at 3835 ka.^[53]

MIS Boundary Gi11/Gi12 is at 3822 ka.^[53]

MIS Boundary Gi10/Gi11 is at 3798 ka.^[53]

MIS Boundary Gi9/Gi10 is at 3768 ka.^[53]

MIS Boundary Gi8/Gi9 is at 3752 ka.^[53]

MIS Boundary Gi7/Gi8 is at 3742 ka.^[53]

MIS Boundary Gi6/Gi7 is at 3719 ka.^[53]

MIS Boundary Gi5/Gi6 is at 3705 ka.^[53]

MIS Boundary Gi4/Gi5 is at 3676 ka.^[53]

MIS Boundary Gi3/Gi4 is at 3660 ka.^[53]

MIS Boundary Gi2/Gi3 is at 3637 ka.^[53]

MIS Boundary Gi1/Gi2 is at 3619 ka.^[53]

Miocene

The Miocene dates from 23.03 x 10⁶ to 5.332 x 10⁶ b2k.

Messinian

Photograph of section Oued Akrech, shows sedimentary cycles OA 1–7 and the position of the Tortonian-Messinian boundary at the base of a reddish bed of cycle OA-15. Credit: F.J. Hilgen, S. Iaccarino, W. Krijgsman, G. Villa, C.G. Langereis, and W.J. Zachariasse.{{fairuse}}

Integrated magnetostratigraphy, calcareous plankton biostratigraphy and cyclostratigraphy of section Oued Akrech is diagrammed. Credit: F.J. Hilgen, S. Iaccarino, W. Krijgsman, G. Villa, C.G. Langereis, and W.J. Zachariasse.{{fairuse}}

"The GSSP of the Messinian Stage, which per definition marks the base of the Messinian and, hence, the boundary between the Tortonian and Messinian Stages of the Upper Miocene Subseries, is Oued Akrech (Morocco) where the Messinian GSSP is now formally designated at the base of the reddish layer of sedimentary cycle no. 15. This point coincides closely with the first regular occurrence (FRO) of the planktonic foraminiferal Globorotalia miotumida group and the first occurrence (FO) of the calcareous nannofossil Amaurolithus delicatus, and falls within the interval of reversed polarity that corresponds to C3Br.1r. The base of the reddish layer and, thus, the Messinian GSSP has been assigned an astronomical age of 7.251 Ma."^[90]

"The correlation of characteristic sedimentary cycle patterns to the astronomical record resulted in an astronomical age of 7.24 Ma (Hilgen et al., 1995), in good agreement with the radiometric age estimates of Vai et al. (1993) and Laurenzi et al. (1997)."^[90]

The integrated magnetostratigraphy, calcareous plankton biostratigraphy and cyclostratigraphy of section Oued Akrech is diagrammed on the left.

Tortonian

G. bilaspurensis jaw is displayed. Credit: Ghedoghedo.

The Tortonian lasted from 11.63 Ma to 7.246 Ma.

Gigantopithecus is an extinct genus of ape that existed from perhaps nine million years to as recently as one hundred thousand years ago, at the same period as Homo erectus would have been dispersed,^[91] in what is now India, Vietnam, China and Indonesia placing Gigantopithecus in the same time frame and geographical location as several hominin species.^[92][93] The primate fossil record suggests that the species Gigantopithecus blacki were the largest known primates that ever lived, standing up to 3 m (9.8 ft) and weighing as much as 540–600 kg (1,190–1,320 lb),^{[91][94][95][96]} although some argue that it is more likely that they were much smaller, at roughly 1.8–2 m (5.9–6.6 ft) in height and 180–300 kg (400–660 lb) in weight.^{[97][98][99][100]}

Paleogene

The Paleogene Period extends from 65.5 ± 0.3 to 23.03 ± 0.05 x 10⁶ b2k.^[101]

Oligocene

The Oligocene dates from 33.9 ± 0.1 x 10⁶ to 23.03 x 10⁶ b2k.

The Oligocene Epoch covers 34 - 23 Mya.

Chattian

The Chattian began 27.82 Ma and ended 23.03 Ma.^[102]

During the Chattian the largest known single-event volcanic eruption occurred: the Fish Canyon Tuff (Fish Canyon eruption) of the La Garita Caldera with a magnitude of 9.2 and VEI of 8.^[103] It has been dated to 27.51 Ma ago.^[104]

Holarctic-Antarctic Ice Age

"This late Cenozoic ice age began at least 30 million years ago in Antarctica; it expanded to Arctic regions of southern Alaska, Greenland, Iceland, and Svalbard between 10 and 3 million years ago. Glaciers and ice sheets in these areas have been relatively stable, more-or-less permanent features during the past few million years."^[105]

Rupelian

The Rupelian began 33.9 Ma and ended 27.82 Ma.^[106]

Eocene

The Eocene dates from 55.8 ± 0.2 x 10⁶ to 33.9 ± 0.1 x 10⁶ b2k.

Priabonian

The Priabonian began 37.8 Ma and ended 33.9 Ma.^[107]

Bartonian

The Bartonian began 41.2 Ma and ended 37.8 Ma.^[108]

Lutetian

The Lutetian began 47.8 Ma and ended 41.2 Ma.^[109]

Ypresian

The Ypresian began 56.0 Ma and ended 47.8 Ma.^[110]

Paleocene

The Paleocene dates from 65.5 ± 0.3 x 10⁶ to 55.8 ± 0.2 x 10⁶ b2k.

Thanetian

The Thanetian began 59.2 Ma and ended 56.0 Ma.^[111]

Selandian

The Selandian began 61.6 Ma and ended at 59.2 Ma.^[112]

Danian

The figure shows the integrated stratigraphy across the K/Pg boundary in the El Kef section. Credit: Eustoquio Molina, Laia Alegret, Ignacio Arenillas, José A. Arz, Njoud Gallala, Jan Hardenbol, Katharina von Salis, Etienne Steurbaut, Noël Vandenberghe, and Dalila Zaghbib-Turki.

This image is a detail of the K/Pg boundary with a Tunisian coin as scale on the rusty layer. Credit: Eustoquio Molina, Laia Alegret, Ignacio Arenillas, José A. Arz, Njoud Gallala, Jan Hardenbol, Katharina von Salis, Etienne Steurbaut, Noël Vandenberghe, and Dalila Zaghbib-Turki.

"Many correlation criteria are present at the GSSP of which the most useful are the meteorite impact evidence (iridium anomaly, Ni-rich spinel, etc.) and the mass extinction of plankic micro- and nannofossils."^[113]

The "GSSP of the K/Pg boundary [is defined] at the base of the boundary clay at the section near El Kef, Tunisia."^[113]

"The section [specifically shown in a closeup on the right] contains marine sediments and sedimentation was as continuous as it could be at a K/Pg boundary. There is a facies change from a grey marl to a black clay (Boundary Clay), at the base of which is a thin rusty layer. This is the fingerprint of continuous sedimentation over the K/Pg boundary interval."^[113]

"Neither magnetostratigraphy nor geochronometry are available at the section near El Kef."^[113]

"The GSSP section near El Kef contains one main feature that allows for a direct correlation of this marine section with continental sections: the Ir anomaly at the base of the Boundary Clay."^[113]

The Global Boundary Stratotype Section and Point for the base of the Danian Stage is also the base GSSP for the Paleocene, Paleogene, "Tertiary", and Cenozoic at El Kef, Tunisia.

"Although crinoids appear not to have been involved in the great change in diversity at the Cretaceous-Paleogene (K-Pg) boundary extinction event, it has been assumed that representatives of order Roveacrinida became extinct during this time. Well-preserved fossils from the Danian (early Paleocene) of Poland demonstrate that these crinoids survived into the earliest Cenozoic."^[114]

Hoploscaphites constrictus johnjagti subsp. nov., adult macroconchs are ammonites from the Danian. Credit: Marcin Machalski.

Post-"Cretaceous ammonites of the genus Hoploscaphites have been found at Stevns Klint in Denmark (Machalski & Heinberg, 2005; Machalski et al., 2009)."^[115]

"The maximum age for Danian scaphitid survivors from the Cerithium Limestone at Stevns Klint, Denmark, has recently been estimated to be around 0.2 Ma following the K–Pg boundary event (Machalski and Heinberg in press). Assuming the Cretaceous– Paleogene boundary at 65.4 ± 0.1 Ma (Jagt and Kennedy 1994), the present study covers more than 4 Ma of the final stages in scaphitid evolution."^[116]

"Scaphitid material from subunit IVf−7 at the very top of the Meerssen Member [...] traditionally regarded to be uppermost Maastrichtian, has recently been reassigned to the lowermost Danian, based on microfossil and strontium isotope evidence (Smit and Brinkhuis 1996). According to Jagt et al. (2003), the scaphitid and baculitid ammonites preserved in subunit IVf−7 are early Danian survivors."^[116]

Above center are Hoploscaphites constrictus johnjagti subsp. nov., adult macroconchs, ammonites from the Danian: A. MGUH 27366, lowermost Danian, Stevns Klint, Denmark, in apertural (A1), lateral (A2, A3), and ventral (A4) views.

Locations on Earth

The diagram shows a composite stratigraphic column for the stratigraphy of the lower part of the Ojo Alamo Sandstone at the San Juan River site. Credit: JE Fassett, SG Lucas, RA Zielinski, and JR Budahn.

The images show the right femur of a hadrosaurian dinosaur from the San Juan River site. Credit: JE Fassett, SG Lucas, RA Zielinski, and JR Budahn.

"A hiatus of about 8 m.y. separates Late Cretaceous from Tertiary rocks in the [San Juan] Basin. Most of the missing strata are from the Maastrichtian Stage. The unconformity is overlain by the Ojo Alamo Sandstone in the south and underlain by the Kirtland or Fruitland Formation at most other places in the basin."^[117]

The right femur of the hadrosaurian dinosaur is shown at left where the bone is in place in A and after excavation, preparation, and mounting in B.

"[P]ollen was the more accurate age indicator and therefore the Ojo Alamo dinosaurs were Paleocene in age. The conclusion was tentative because Paleocene pollen nowhere occurred at exactly the same locality as dinosaur bone. Paleocene pollen is present, however, in the Ojo Alamo near Barrel Spring, within one mile of the Alamo Wash bone locality [...]."^[117]

"A Cretaceous dinosaur bone collected from just below the Cretaceous-Paleogene interface yielded a U-Pb date of 73.6 ± 0.9 Ma, in excellent agreement with a previously determined ⁴⁰Ar/³⁹Ar date of 73.04 ± 0.25 Ma for an ash bed near this site. The second dinosaur bone sample from Paleocene strata just above the Cretaceous-Paleogene interface yielded a Paleocene U-Pb date of 64.8 ± 0.9 Ma, consistent with palynologic, paleomagnetic, and fossil-mammal biochronologic data."^[118]

"The second bone sample BB-1, a fragment of a large sauropod femur (Alamosaurus sanjuanensis) was collected from the Paleocene Ojo Alamo Sandstone. This bone shows much less geochemical variation than bone 22799-D and is very well preserved. The weighted average ²⁰⁶Pb/²³⁸U date of 64.8±0.9 Ma is interpreted to record the time of bone fossilization. Considering that fossilization times are typically less than a few thousand years, the age result from BB-1 confirms the existence of Paleocene dinosaurs. The strontium isotopic composition of both bones are relatively unradiogenic (0.70811±3 and 0.70860±3, respectively). The strontium content of both bones is remarkably homogeneous, in contrast to the chemical variability displayed by most elements, therefore we interpret the strontium isotope values to reflect the indigenous bone composition."^[119]

Hypotheses

1. Each time frame or span of time in the geochronology of the Cenozoic has at least one dating technique.

See also

References