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Postglacial human colonization of Fennoscandia
Postglacial human colonization of Fennoscandia
1.1
Paul M. Dolukhanov Newcastle University, Newcastle upon Tyne, Great Britain The early man communities were settling Fennoscandia and the entire basin of the Baltic Sea throughout the Late Glacial time. As has been proven by numerous investigators, the Paleolithic population over a greater part of extraglacial Europe was dramatically reduced in density during the Last Glacial Maximum (Housley et al., 1997; Tarberger and Street, 2002). There existed, however, two refugia where the population density was steadily growing through that interval. One of the refugia developed in the southwest of Europe (Franco-Cantabrian region), and another developed in the east, including the drainage basin of the Vistula and the upper reaches of the Dniester, Dnieper, and Don rivers (Dolukhanov, 1986; Dolukhanov et al., 2002; Gamble et al., 2006). In the course of the Late Glacial, under conditions of increasing heat and moisture supply, along with growing efficiency of the hunting activities, the resource base of the Paleolithic groups became drastically diminished. That stimulated a gradual outflow of people from the refugia into other regions of Northern Europe and Fennoscandia noted for a greater food potential (Fig. 1.1.1). Having analyzed the frequency distribution of the radiocarbon dates, Gamble et al. (2006) distinguished several stages in the demographic dynamics of the dispersal process from the western refugium as follows: • initial: 29.5–16 ka BP; • principal: 16–14 ka BP; • static: 14–13 ka BP; • recessionary: 13–11.5 ka BP.
It has been supposed (Dolukhanov, 1986; Nuñez, 1987; Bjerck, 2008; Zvelebil, 2008) that the European North was colonized by people arriving from both refugia (Fig. 1.1.1). The tool typology suggests that the west of Scandinavia was settled by newcomers from the area of the “Ahrensburgian technocomplex”; the new settlers arrived by way of the so-called “Northern Corridor,” that is, part of the North Atlantic shelf between the Scandinavian ice sheet lobe and the coastline having retreated westward at that time. The further movement of the people northward and the appearance of the Komsa culture sites on the coasts of Norway and the Kola Peninsula resulted from a high-speed migration, probably with the usage of floating crafts, about 10,200–8900 yr BP (9500–8900 cal. yr BC). In the process of this migration the hunting activities were somewhat reoriented: instead of hunting reindeer exclusively, they began to use various marine resources, marine mammals in particular.
Human Colonization of the Arctic: The Interaction Between Early Migration and the Paleoenvironment http://dx.doi.org/10.1016/B978-0-12-813532-7.00001-2 Copyright © 2017 Elsevier Inc. All rights reserved.
8
Human Colonization of the Arctic
>9,600
10,280
1
9,610
9,500-9,100
9,400
2
9,200
8,290
Ice sheet
3
~ 8,000 yr BP
9,400
4
8,950 8,440
5
8,150
Ice sheet
8,840 9,300-8,900
~ 10,000 yr BP 10,300
9,600
9,200
9,000 9,400 10,100
9,400
10,100
9,300
13,200
9,500 9,310
11,000 10,300
9,700
11,200
10,550-9,820
13,600 13,400 13,200
13,400 13,400 14,200
Figure 1.1.1 Postglacial colonization of Northern Europe (Zvelebil, 2008). 1: recolonization from Eastern Europe; 2: recolonization from Southwestern Europe; 3: first regional settlements and their age; 4: Late Glacial coastlines and emerged sea floor; 5: the Yoldia sea.
The earliest sites in the Scandinavian North (Finmarken) are traditionally attributed to the Komsa culture, while those in the south of western Norway to Fosna culture. The earlier phase (1) is dated to the Preboreal period, its age being established by correlation with coastlines as 10–9 ka BP (9500–8250 cal. yr BC) (Olsen, 1994; Woodman, 1993). Typological correlations with complexes of Ahrensburgian type in Germany and Holland confirm the notion of the initial peopling from south to north. At earlier stages the economy was based of the reindeer hunt; later, it was replaced by red deer and seals (Phoca vitulina, Halichoerus grypus) as the main objects of hunting. The earliest site in the inner part of Finnish Lapland is Sujala on Vetsijarvi Lake dated at 8600–7800 cal. yr BC. Judging from the presence of Post-Swiderian elements in the stone inventory, one may suppose that the inhabitants of the site could come here from the drainage basin of the Upper Volga River (Rankama and Kankäänpaa, 2007). The earlier stages in colonization of the northeastern Baltic region are marked by sites of Mesolithic type. The earliest dates were obtained for the Antrea Korpilahti locality northeast of Vyborg. Some implements of the Mesolithic type, including a birchbark fishing net and some floats, were dated at 9200–8250 yr BC (Matiskainen,
Postglacial human colonization of Fennoscandia
9
Alces Castor Rangifer Phoca
9 РВ В Ancylus
8 АТ1
7 Litorina
АТ2
6
5 ka BP SB
Figure 1.1.2 Changes in proportions of animals: objects of hunt in the Mesolithic of Finland (Matiskainen, 1989).
1989). Judging from the geological context, the Mesolithic type artifacts were initially deposited in a lagoon or a pool belonging to the Ladoga-Baltic strait system. A similar date was obtained for Saarenoja locality, Joutseno region (9300 ± 75 yr BC). In the course of time, there appeared a network of Mesolithic sites attributed to Suomusjärvi culture. According to classification developed by Zvelebil (2008), the Mesolithic sites of the European North belong to the type of “foraging economy with some elements of long-term preservation of products (delayed consumption).” Having analyzed the available data on fauna obtained from the Mesolithic sites of southern Finland, Matiskainen (1989) identified a certain regularity in the hunting, fishing, and gathering activities and their specific distribution over seasons (Figs. 1.1.2 and 1.1.3). Since 9500 yr BP the seal hunting had acquired a considerable importance in the Mesolithic economy of coastal regions (Ukkonen, 2002), particularly so after the beginning of pottery production; the faunal materials recovered from the Early Ceramic sites include remains of two species of seals: Phoca hispida and Phoca groenlandica. Judging from the data available, the economy of Mesolithic settlements in Karelia and in northeastern Russia was oriented to hunting forest animals (reindeer, red deer, boar, beaver) and waterfowl, with fishing being also of great importance (Oshibkina, 1996). The Mesolithic sites were concentrated on the coasts of the Gulf of Finland, inner lakes, and streams connecting them (Fig. 1.1.4). Inland sites occurred usually on terraces of large rivers (such as the Severnaya Dvina, Pechora, Sukhona, Vychegda, and their tributaries). Large settlements have been discovered on low terraces of lakes Kubenskoye, Vozhe, and Lacha. At the Nizhnee Veretye 1 settlement excavated over an area of ∼1500 m2, there have been found remains of surface dwellings with postholes and a hearth, indicative of a sedentary lifestyle. Large Mesolithic burials are found in the north of Russia: Oleni Ostrov (Gurina, 1956) and Popovo (Oshibkina, 1996). The materials retrieved from the largest in Europe Oleni Ostrov burial ground on Onega Lake led specialists (O’Shea and Zvelebil, 1984) to the conclusion that the site belonged to “a large sedentary community with a distinct social stratification.” The pieces of art recovered from the burial suggest sophisticated esthetic concepts typical of the communities of that type.
10
Human Colonization of the Arctic
(a)
Esox
Pisces
Perca
Cyprinoidei Salmonidae Lucioperca
(b)
Phoca hispida
(c)
Castor
(d)
Alces
(e)
Anatidae
(f)
Plants
I
II
III
IV
V
VI
VII
VIII
IX
X
XI
XII
I
Figure 1.1.3 Seasonal cycles of hunting, fishing, and gathering in the Mesolithic of Finland (Matiskainen, 1989).
A large series of radiocarbon dates obtained for Mesolithic sites of the Russian North fall in the range of 9600–6000 yr BP. The Early Ceramic sites (of ka I:1 or Sperrings 1 type) were first identified by Äyräpää (Europaeus) (1925). Hyyppä (1937) correlated the sites of this type with coastlines of the second Litorina transgression of the Baltic Sea. In the opinion of Siiriäinen (1970, 1982), the earliest sites of Sperrings type were related to the coastline of Päijänne Lake (southern Finland) at its maximum transgression (5200 yr BC). In common with the earlier settlements, the Sperrings sites were mostly located on the sea and lake coasts or on river banks, mainly in Southern Finland and Karelia. The type of economy was also much the same. Judging from the analysis of stable isotopes in the bones recovered from early ceramics sites in Sweden, the people’s diet consisted mostly of seal meat and fish at that time (Fornander, 2006). There are several types of Sperrings ceramics (German, 2002) (Fig. 1.1.5): • large vessels with the vessel mouth diameter being 30–50 cm and an average wall thickness of 0.8–1.3 cm; the bottom is rounded or tapered; • slightly smaller vessels, with mouth diameter of 20–30 cm, wall thickness of 0.4–0.7 cm, with a slanted or tapered bottom;
Postglacial human colonization of Fennoscandia
11
Figure 1.1.4 Mesolithic and Early Neolithic sites in Fennoscandia and in northern Russia. 1: Mesolithic sites; 2: Neolithic sites; Neolithic cultures of Eastern Europe marked by numbers: 1, Sperrings; 2, Narva-Neman; 3, Upper Volga.
• smaller vessels with round bottom, mouth diameter about 20 cm and wall thickness of 0.5–0.7 cm; • small vessel-saucers with the mouth diameter of 12 cm and wall thickness of 0.5–0.7 cm.
Some impurities in the clay are found only in the ceramic material of larger vessels; the impurities are most often sand, as well as quartz grains and ground granite. An organic matter admixture is found in western regions. All the potteries were molded out of clay by hand and then subjected to firing in open kilns. The firing temperature was rather low, as follows from the dark color of pieces (from dark gray to grayish-brown) and a fragility of pieces. The ornament consists mainly of fish vertebra impressions. The second most often used ornament is drawn lines. Many pots were ornamented with imprints of comb or of “twined cord.” Pits were usually imprinted above the earlier made ornament. The sites of the Säräisniemi type (Sär 1) are found in northern and northeastern Fennoscandia, including Karelia. Ceramics of that type have usually much in common with the Sperrings ones and are often considered to be a northern variety of the latter. Principal distinctions are in impurities: the Säräisniemi ceramics contain organic matter and micas. In most cases an ornament covers the entire surface of vessels (Fig. 1.1.6). Many radiocarbon dates have been obtained for the Early Ceramics of Finland and Northern Russia. As is seen from the frequency distribution of the dates, they fall
12
Human Colonization of the Arctic
Figure 1.1.5 Ceramics of Sperrings type (German, 2006).
within a broad range of 7000–3500 yr BC, the greater frequencies corresponding to the interval of 6000–3500 yr BC (Fig. 1.1.7). The dates of the Säräisniemi sites calculated from the shoreline gradients give the age of approximately 6100–5500 yr BC (Torvinen, 1997, 1998, 2000). Sites of the same type in the north of Norway correspond to the “Stone Age I” of the regional scale and are dated at 5800–5000 yr BC (Bjerck, 2008). In common with the neighboring regions of Norway, the Mesolithic and Early Neolithic (Ceramic) sites on the Kola Peninsula are usually found close to the ancient marine coastlines in fiords or on small islands, as well as along river valleys and on lacustrine terraces (Gurina, 1997; Shumkin, 1996). Organic remains seldom occur at the sites. By analogy with the Early Neolithic sites, it is assumed that the economy was mostly based on sea mammal hunting. The early ceramics described on the Kola Peninsula bear some features characteristic of the Sperrings and Säräisniemi type. Gurina (1997), however, regarded it as an individual Neolithic culture and described it under the name of “the Kola Culture.” The largest concentration of the sites is found at the Drozdovka Bay (fiord). The earliest dates have been obtained for sites Ust’-Drozdovka (5510 ± 100 yr
Postglacial human colonization of Fennoscandia
13
Figure 1.1.6 Ceramics of Säräisniemi type (German, 2006). 14 12
Frequency
10 8 6 4 2 0
2000
3000
4000 5000 14 Age cal. yr BP
6000
7000
Figure 1.1.7 Frequency distribution of the Neolithic radiocarbon dates in Northern Russia.
14
Human Colonization of the Arctic
BP/6300 ± 110 cal. yr BP) and Nerpichya (4630 ± 100 yr BP/5320 ± 160 cal. yr BP) on the northern coast and Chavan’ga site (5560 ± 80 yr BP/6360 ± 80 cal. yr BP) on the southern coast. As to the central part of the peninsula, there is a series of dates at the Tsaga site (Lake Lovozero), the oldest being 5760 ± 160 yr BP/6590 ± 180 cal. yr BP.
1.1
Paul M. Dolukhanov Newcastle University, Newcastle upon Tyne, Great Britain The early man communities were settling Fennoscandia and the entire basin of the Baltic Sea throughout the Late Glacial time. As has been proven by numerous investigators, the Paleolithic population over a greater part of extraglacial Europe was dramatically reduced in density during the Last Glacial Maximum (Housley et al., 1997; Tarberger and Street, 2002). There existed, however, two refugia where the population density was steadily growing through that interval. One of the refugia developed in the southwest of Europe (Franco-Cantabrian region), and another developed in the east, including the drainage basin of the Vistula and the upper reaches of the Dniester, Dnieper, and Don rivers (Dolukhanov, 1986; Dolukhanov et al., 2002; Gamble et al., 2006). In the course of the Late Glacial, under conditions of increasing heat and moisture supply, along with growing efficiency of the hunting activities, the resource base of the Paleolithic groups became drastically diminished. That stimulated a gradual outflow of people from the refugia into other regions of Northern Europe and Fennoscandia noted for a greater food potential (Fig. 1.1.1). Having analyzed the frequency distribution of the radiocarbon dates, Gamble et al. (2006) distinguished several stages in the demographic dynamics of the dispersal process from the western refugium as follows: • initial: 29.5–16 ka BP; • principal: 16–14 ka BP; • static: 14–13 ka BP; • recessionary: 13–11.5 ka BP.
It has been supposed (Dolukhanov, 1986; Nuñez, 1987; Bjerck, 2008; Zvelebil, 2008) that the European North was colonized by people arriving from both refugia (Fig. 1.1.1). The tool typology suggests that the west of Scandinavia was settled by newcomers from the area of the “Ahrensburgian technocomplex”; the new settlers arrived by way of the so-called “Northern Corridor,” that is, part of the North Atlantic shelf between the Scandinavian ice sheet lobe and the coastline having retreated westward at that time. The further movement of the people northward and the appearance of the Komsa culture sites on the coasts of Norway and the Kola Peninsula resulted from a high-speed migration, probably with the usage of floating crafts, about 10,200–8900 yr BP (9500–8900 cal. yr BC). In the process of this migration the hunting activities were somewhat reoriented: instead of hunting reindeer exclusively, they began to use various marine resources, marine mammals in particular.
Human Colonization of the Arctic: The Interaction Between Early Migration and the Paleoenvironment http://dx.doi.org/10.1016/B978-0-12-813532-7.00001-2 Copyright © 2017 Elsevier Inc. All rights reserved.
8
Human Colonization of the Arctic
>9,600
10,280
1
9,610
9,500-9,100
9,400
2
9,200
8,290
Ice sheet
3
~ 8,000 yr BP
9,400
4
8,950 8,440
5
8,150
Ice sheet
8,840 9,300-8,900
~ 10,000 yr BP 10,300
9,600
9,200
9,000 9,400 10,100
9,400
10,100
9,300
13,200
9,500 9,310
11,000 10,300
9,700
11,200
10,550-9,820
13,600 13,400 13,200
13,400 13,400 14,200
Figure 1.1.1 Postglacial colonization of Northern Europe (Zvelebil, 2008). 1: recolonization from Eastern Europe; 2: recolonization from Southwestern Europe; 3: first regional settlements and their age; 4: Late Glacial coastlines and emerged sea floor; 5: the Yoldia sea.
The earliest sites in the Scandinavian North (Finmarken) are traditionally attributed to the Komsa culture, while those in the south of western Norway to Fosna culture. The earlier phase (1) is dated to the Preboreal period, its age being established by correlation with coastlines as 10–9 ka BP (9500–8250 cal. yr BC) (Olsen, 1994; Woodman, 1993). Typological correlations with complexes of Ahrensburgian type in Germany and Holland confirm the notion of the initial peopling from south to north. At earlier stages the economy was based of the reindeer hunt; later, it was replaced by red deer and seals (Phoca vitulina, Halichoerus grypus) as the main objects of hunting. The earliest site in the inner part of Finnish Lapland is Sujala on Vetsijarvi Lake dated at 8600–7800 cal. yr BC. Judging from the presence of Post-Swiderian elements in the stone inventory, one may suppose that the inhabitants of the site could come here from the drainage basin of the Upper Volga River (Rankama and Kankäänpaa, 2007). The earlier stages in colonization of the northeastern Baltic region are marked by sites of Mesolithic type. The earliest dates were obtained for the Antrea Korpilahti locality northeast of Vyborg. Some implements of the Mesolithic type, including a birchbark fishing net and some floats, were dated at 9200–8250 yr BC (Matiskainen,
Postglacial human colonization of Fennoscandia
9
Alces Castor Rangifer Phoca
9 РВ В Ancylus
8 АТ1
7 Litorina
АТ2
6
5 ka BP SB
Figure 1.1.2 Changes in proportions of animals: objects of hunt in the Mesolithic of Finland (Matiskainen, 1989).
1989). Judging from the geological context, the Mesolithic type artifacts were initially deposited in a lagoon or a pool belonging to the Ladoga-Baltic strait system. A similar date was obtained for Saarenoja locality, Joutseno region (9300 ± 75 yr BC). In the course of time, there appeared a network of Mesolithic sites attributed to Suomusjärvi culture. According to classification developed by Zvelebil (2008), the Mesolithic sites of the European North belong to the type of “foraging economy with some elements of long-term preservation of products (delayed consumption).” Having analyzed the available data on fauna obtained from the Mesolithic sites of southern Finland, Matiskainen (1989) identified a certain regularity in the hunting, fishing, and gathering activities and their specific distribution over seasons (Figs. 1.1.2 and 1.1.3). Since 9500 yr BP the seal hunting had acquired a considerable importance in the Mesolithic economy of coastal regions (Ukkonen, 2002), particularly so after the beginning of pottery production; the faunal materials recovered from the Early Ceramic sites include remains of two species of seals: Phoca hispida and Phoca groenlandica. Judging from the data available, the economy of Mesolithic settlements in Karelia and in northeastern Russia was oriented to hunting forest animals (reindeer, red deer, boar, beaver) and waterfowl, with fishing being also of great importance (Oshibkina, 1996). The Mesolithic sites were concentrated on the coasts of the Gulf of Finland, inner lakes, and streams connecting them (Fig. 1.1.4). Inland sites occurred usually on terraces of large rivers (such as the Severnaya Dvina, Pechora, Sukhona, Vychegda, and their tributaries). Large settlements have been discovered on low terraces of lakes Kubenskoye, Vozhe, and Lacha. At the Nizhnee Veretye 1 settlement excavated over an area of ∼1500 m2, there have been found remains of surface dwellings with postholes and a hearth, indicative of a sedentary lifestyle. Large Mesolithic burials are found in the north of Russia: Oleni Ostrov (Gurina, 1956) and Popovo (Oshibkina, 1996). The materials retrieved from the largest in Europe Oleni Ostrov burial ground on Onega Lake led specialists (O’Shea and Zvelebil, 1984) to the conclusion that the site belonged to “a large sedentary community with a distinct social stratification.” The pieces of art recovered from the burial suggest sophisticated esthetic concepts typical of the communities of that type.
10
Human Colonization of the Arctic
(a)
Esox
Pisces
Perca
Cyprinoidei Salmonidae Lucioperca
(b)
Phoca hispida
(c)
Castor
(d)
Alces
(e)
Anatidae
(f)
Plants
I
II
III
IV
V
VI
VII
VIII
IX
X
XI
XII
I
Figure 1.1.3 Seasonal cycles of hunting, fishing, and gathering in the Mesolithic of Finland (Matiskainen, 1989).
A large series of radiocarbon dates obtained for Mesolithic sites of the Russian North fall in the range of 9600–6000 yr BP. The Early Ceramic sites (of ka I:1 or Sperrings 1 type) were first identified by Äyräpää (Europaeus) (1925). Hyyppä (1937) correlated the sites of this type with coastlines of the second Litorina transgression of the Baltic Sea. In the opinion of Siiriäinen (1970, 1982), the earliest sites of Sperrings type were related to the coastline of Päijänne Lake (southern Finland) at its maximum transgression (5200 yr BC). In common with the earlier settlements, the Sperrings sites were mostly located on the sea and lake coasts or on river banks, mainly in Southern Finland and Karelia. The type of economy was also much the same. Judging from the analysis of stable isotopes in the bones recovered from early ceramics sites in Sweden, the people’s diet consisted mostly of seal meat and fish at that time (Fornander, 2006). There are several types of Sperrings ceramics (German, 2002) (Fig. 1.1.5): • large vessels with the vessel mouth diameter being 30–50 cm and an average wall thickness of 0.8–1.3 cm; the bottom is rounded or tapered; • slightly smaller vessels, with mouth diameter of 20–30 cm, wall thickness of 0.4–0.7 cm, with a slanted or tapered bottom;
Postglacial human colonization of Fennoscandia
11
Figure 1.1.4 Mesolithic and Early Neolithic sites in Fennoscandia and in northern Russia. 1: Mesolithic sites; 2: Neolithic sites; Neolithic cultures of Eastern Europe marked by numbers: 1, Sperrings; 2, Narva-Neman; 3, Upper Volga.
• smaller vessels with round bottom, mouth diameter about 20 cm and wall thickness of 0.5–0.7 cm; • small vessel-saucers with the mouth diameter of 12 cm and wall thickness of 0.5–0.7 cm.
Some impurities in the clay are found only in the ceramic material of larger vessels; the impurities are most often sand, as well as quartz grains and ground granite. An organic matter admixture is found in western regions. All the potteries were molded out of clay by hand and then subjected to firing in open kilns. The firing temperature was rather low, as follows from the dark color of pieces (from dark gray to grayish-brown) and a fragility of pieces. The ornament consists mainly of fish vertebra impressions. The second most often used ornament is drawn lines. Many pots were ornamented with imprints of comb or of “twined cord.” Pits were usually imprinted above the earlier made ornament. The sites of the Säräisniemi type (Sär 1) are found in northern and northeastern Fennoscandia, including Karelia. Ceramics of that type have usually much in common with the Sperrings ones and are often considered to be a northern variety of the latter. Principal distinctions are in impurities: the Säräisniemi ceramics contain organic matter and micas. In most cases an ornament covers the entire surface of vessels (Fig. 1.1.6). Many radiocarbon dates have been obtained for the Early Ceramics of Finland and Northern Russia. As is seen from the frequency distribution of the dates, they fall
12
Human Colonization of the Arctic
Figure 1.1.5 Ceramics of Sperrings type (German, 2006).
within a broad range of 7000–3500 yr BC, the greater frequencies corresponding to the interval of 6000–3500 yr BC (Fig. 1.1.7). The dates of the Säräisniemi sites calculated from the shoreline gradients give the age of approximately 6100–5500 yr BC (Torvinen, 1997, 1998, 2000). Sites of the same type in the north of Norway correspond to the “Stone Age I” of the regional scale and are dated at 5800–5000 yr BC (Bjerck, 2008). In common with the neighboring regions of Norway, the Mesolithic and Early Neolithic (Ceramic) sites on the Kola Peninsula are usually found close to the ancient marine coastlines in fiords or on small islands, as well as along river valleys and on lacustrine terraces (Gurina, 1997; Shumkin, 1996). Organic remains seldom occur at the sites. By analogy with the Early Neolithic sites, it is assumed that the economy was mostly based on sea mammal hunting. The early ceramics described on the Kola Peninsula bear some features characteristic of the Sperrings and Säräisniemi type. Gurina (1997), however, regarded it as an individual Neolithic culture and described it under the name of “the Kola Culture.” The largest concentration of the sites is found at the Drozdovka Bay (fiord). The earliest dates have been obtained for sites Ust’-Drozdovka (5510 ± 100 yr
Postglacial human colonization of Fennoscandia
13
Figure 1.1.6 Ceramics of Säräisniemi type (German, 2006). 14 12
Frequency
10 8 6 4 2 0
2000
3000
4000 5000 14 Age cal. yr BP
6000
7000
Figure 1.1.7 Frequency distribution of the Neolithic radiocarbon dates in Northern Russia.
14
Human Colonization of the Arctic
BP/6300 ± 110 cal. yr BP) and Nerpichya (4630 ± 100 yr BP/5320 ± 160 cal. yr BP) on the northern coast and Chavan’ga site (5560 ± 80 yr BP/6360 ± 80 cal. yr BP) on the southern coast. As to the central part of the peninsula, there is a series of dates at the Tsaga site (Lake Lovozero), the oldest being 5760 ± 160 yr BP/6590 ± 180 cal. yr BP.