Elsevier Encyclopedia of Geology

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sea-level changes and isostatic uplift or subsidence,

partly modified by tectonic movements, produced

considerable changes in the geography of Europe

during the Holocene. Depending on the geographic

position of the affected area, large relative sea-level

changes (positive or negative ones) have occurred

(Figure 7). These changes are particularly obvious

where large intracontinental basins like the recent

Baltic Sea area were affected.

At the beginning of the Holocene, large parts of the

Baltic Basin were filled with freshwater from the Baltic

Ice Lake which was fed mainly by meltwater from a

large glaciated area in North and north-eastern Europe.

The only important outlet in the O

resound (between

the recent Danish island Sealand and southern Sweden)

was too narrow to serve as a sufficient spillway be-

tween the Baltic Ice Lake and the North Sea. The global

sea-level was about 25 metres lower than in the Baltic

Ice Lake. When the Scandinavian inland ice started

to retreat from southern Sweden, a spillway through

the central Swedish Depression was opened. As a

dramatic process, half of the recent Baltic Sea’s

water volume drained into the Atlantic Ocean via

the Kattegat and North Sea. This drainage took no

longer than a few years and had an enormous impact

along the former shores of the Baltic Ice Lake. Large

areas previously covered by water became dry land,

and southern Scandinavia became directly connected

to central Europe. Saline waters of the Kattegat could

enter the Baltic Basin for a time-span of a few hun-

dred years, a stage of the Baltic Sea’s development

known as the Yoldia Sea, a phase which is dated from

11 570 to 10 700 years BP (Figure 8).

The connection between the Yoldia Sea and the Kat-

tegat through central Sweden was located in a rapidly

uplifting region. Therefore, the connection closed at

about 10 700 years BP and a newly dammed-up fresh-

water lake was formed within the Baltic Basin. It

Figure 5 Recent vertical movement of the Earth’s crust. In the northern part the map is dominated by the extensive, north-east-

south-west-stretched uplift of Fennoscandia with maximum values of >8 mm year. The subsidence of a belt surrounding the Baltic

Shield is less differentiated. (From Harff J, Frischbutter A, Lampe R, and Meyer M (2001) Sea-level change in the Baltic Sea:

interrelation of climatic and geological processes. In: Gerhard LC, Harrison WE, and Hanson BM (eds.)

Geological perspectives of global

climate change

. Tulsa, Oklahoma, American Association of Petroleum Geologists in collaboration with the Kansas Geological Survey

and the AAPG Division of Environmental Geosciences: 231–250. Reprinted by permission of the AAPG whose permission is required

for further use.)

150 EUROPE/Holocene

is called Ancylus Lake, with reference to a typical

freshwater snail occurring in these waters (Ancylus

fluviatilis)(Figure 9). This freshwater stage lasted

more than two thousand years and was characterised

by considerable short-term water level fluctuations. As

differential isostatic uplift continued, the critical

thresholds between the Baltic Basin and Kattegat

moved from southern Sweden to the recent-formed

Danish Straits. At about 8000 years BP, the eustatic

sea-level rise led to the first ingressions of marine

waters into the Baltic Basin. In pace with the rapidly

rising global sea-level, the thresholds were flooded

and a stable connection between the Kattegat and the

Baltic Basin was formed. This crucial phase of

the Baltic Sea’s evolution is called the Littorina trans-

gression, after a marine snail which is common in

deposits of this period (Littorina littorea). At the

onset of the Littorina transgression, the water level

rose at a rate of 25 mm year within the south-western

Baltic Basin (eustatic rise added to crustal subsidence,

as described above), which slowed down later to

about 3 mm year at about 4500 years BP (Figure 10).

During a time-span of less than a thousand years, the

sea-level rose by more than 20 m, implying enormous

rates of coastal retreat within the southern Baltic

Basin. Due to the rapidly rising sea-level at the begin-

ning of the Littorina Stage, the glaciogenically-shaped

land relief was drowned without any notable coastal

erosion and longshore transport processes of sedi-

mentary material. The resulting geographical situ-

ation is shown in Figure 11. Only after the sea-level

rise slowed down at the end of the Littorina Stage

(about 2000 years BP), and during the Post-Littorina

Stage, was the recent spit and barrier coast formed by

erosion and sediment transport. This process was

mainly controlled by climatic factors, such as the

wind-driven hydrographic regime which was super-

imposed on long-term eustatic and isostatic move-

ments which have caused rising relative sea-levels

and coastal retreat at the southern Baltic shores in

recent times. Further north in Fennoscandia, isostatic

uplift continuously exceeded the eustatic sea-level

rise, resulting in a permanent general sea regression

(Figure 7).

The changing Holocene sea level within the Mediter-

ranean basins was and is mainly controlled by eustatic

processes. In contrast to northern Europe, glacio-

isostasy does not play a significant role. On the other

hand, this region occupies the junction between the

African-Arabian and the Eurasian plates which gives

considerable tectonic activity in the different sediment-

ary basins of the Mediterranean Sea. Therefore, the

general picture of the sea-level, development which

reflects the eustatic curves, is superimposed on the

regional and local tectonics.

A matter of ongoing discussion is the possibility of

the reconnection of the Black Sea and the Mediterra-

nean Sea during the period of Holocene sea-level rise.

A catastrophic flood scenario at about 7500 years BP

Figure 6 Principle of glacio-isostatic vertical crustal move-

ments: (a) Ice load causes subsidence of the Earth’s crust

below and compensatory uplift beyond the ice margin as a fore-

bulge; (b) Uplift of the ice-released Earth’s crust and related

displacement of the forebulge. (Modified after Daly 1934.)

Figure 7 Schematic Holocene relative sea level curves for

different European regions (blue = Oslo, Norway; yellow =

south-eastern Sweden; light blue = southern Baltic Sea; brown

= French Atlantic coast; green = Netherlands; purple = central

Mediterranean).

EUROPE/Holocene 151

is questioned because of indications of a more com-

plex and progressive transgression process over the

past 12 000 years.

Interrelation of Human Activity and

Natural Environment

In terms of human history, the onset of the Holocene

is equivalent to the beginning of the Mesolithic

period, which is characterised by prevailing hunter,

fisher, and gatherer societies in Europe. The tempera-

ture rise at the end of the Younger Dryas caused an

accelerated deglaciation. Alpine glaciers retreated to

historical dimensions and the receding inland ice in

Scandinavia was followed successively by tundra,

steppe, and finally forests. This was accompanied by

an enhanced northward migration of animals and

their Mesolithic hunters. The rapidly changing nat-

ural environment, possibly in combination with

human activity, resulted in the extinction of some

characteristic genera of the Pleistocene megafauna

such as the mammoth (see Tertiary To Present: Pleis-

tocene and The Ice Age). Another consequence of the

rapidly changing landscapes was a very variable

migration pattern of the Mesolithic hunter, fisher,

and gatherer groups in central and north-western

Europe.

The following Neolithic period was closely con-

nected with the introduction of farming in the various

geographical regions. The first Neolithic settlements

in southern Europe (Greece) are dated to about 9000

calendar years BP. In northern Germany, southern

Scandinavia and the British Isles, they are more than

3000 years younger. Coming from the Near East, the

new method of food-procurement spread to the Great

Hungarian Plain in a first wave from 8200–7800

years BP. A second leap entered the North European

Plain at around 7400 years BP. Neolithic settlers from

Southeast Europe migrating along the rivers Danube

and Rhine were probably responsible for the conse-

quent social and cultural changes. In parts of Europe

(e.g., western Mediterranean and northern Europe)

the native Mesolithic population adopted agricultural

methods to form a transitional economy.

While the hunter-fisher-gatherer societies of the

Mesolithic used and manipulated the natural ecosystem

without altering it considerably, the Neolithic farmers

started to transform the environment according to their

Figure 8 North-western Europe during the Yoldia Sea stage of the Baltic Sea’s history (about 11 000 years BP). (From Andersen BG

and Borns HW (1994)

The ice age world: an introduction to Quaternary history and research with emphasis on North America and Europe during the

last 2.5 million years

. Oslo: Scandinavian University Press, with permission.)

152 EUROPE/Holocene

needs. Cultivation started within rather small (perhaps

pre-existing) open land patches in the Early Neolithic.

In this phase clearances remained localised and the early

Neolithic farmers were still highly dependent on intact

natural habitats surrounding the cultivated land

patches.

This situation changed in the later part of the Euro-

pean Holocene, when increasing demand for agricul-

tural products induced a major transformation of the

yet still mainly natural environment into an agricul-

tural one. This process was certainly time-transgres-

sive and affected some European regions more than

others. But, far from being controlled solely by

human action, natural feedback, combined with

differing vulnerability of the existing ecosystems,

amplified, shifted, or interfered with the initial direc-

tion of processes initiated by human activity. In order

to adapt to the partly self-induced new conditions,

human societies had to react by further cultural de-

velopment which accelerated the general transform-

ation process of the natural environment. This is

exemplified by the domestication of animals which

were advantaged by the anthropogenically influenced

environment, while on the other hand natural com-

petitors and predators became progressively extinct

by hunting kill-off or simply by loss of habitat (exten-

sive land use by farming). The same applies to floral

assemblages, as initially, their composition was

governed by natural conditions but it became increas-

ingly influenced by agriculture. This development

finally produced an increasing interdependence of

cultivated plants and animals with mankind. Societies

like the Irish people in nineteenth century, for exam-

ple, were greatly dependent on potato growth. When

the Late Potato Blight ruined all the potato crop in

Ireland in the 1840s, the resulting famine lead to

dramatic consequences. About 1 million people died

while another 1.5 million people emigrated.

The stability of the cultural landscape which had

evolved out of the interplay between natural and

human influences, as well as that of human societies

living there, depended on the state of their equilib-

rium. Changes of the natural component could cause

considerable impact to the progressively complex

human society and this is exemplified by climatic or

geological influences. Some historical epochs with a

prospering economy and politically stable conditions

are connected with warmer periods.

Colder climate deviations often were characterised

by political and economical instability. This refers,

for example, to the time of the Germanic migrations

about 450–700 ad and the Little Ice Age between

1500 and 1800 ad. Rather short-term, but possibly

catastrophic, impacts derived from events like

Figure 9 North-western Europe during the Ancylus Lake stage of the Baltic Sea’s history (about 9500 years BP). (From Andersen BG

and Borns HW (1994)

The ice age world: an introduction to Quaternary history and research with emphasis on North America and Europe during the

last 2.5 million years

. Oslo: Scandinavian University Press, with permission.)

EUROPE/Holocene 153

volcanism (e.g., the eruption of Vesuvius in ad 79

described by Pliny the Younger), earthquakes (e.g.,

the disastrous one of Lisboa in ad 1755) or floods

along rivers and seashores.

On the other hand, changing social conditions also

induced dramatic changes of their natural environ-

ment. Once human activity stopped or declined, the

surrounding environment developed depending on its

natural stability. Robust ecosystems changed back

to a state similar to the original one being controlled

by the natural conditions. An example for such pro-

cesses is the re-forestation after depopulation during

the Thirty Years’ War (1618–1648 ad) in central

Europe.

In other cases, human activity led to irreversible

effects on the ecosystem’s stability when the social

structures collapsed. During the Roman period there

was a land use maximum partly on metastable

soils. Here, terraces were maintained, preventing soil

erosion. After the invasion of eastern nomads, the

land was partly abandoned and soil erosion started

at a greater extent and in the worst case, barren bad-

lands were the final result. Therefore, maximum ero-

sion is not connected with maximum land use, but

with subsequent phases in different cultural environ-

ments. Generally, when judging human impact on the

natural environment, it is often regarded only as

negative. However, in contrast, the creation of new

metastable ecosystems more diverse than before, par-

ticularly in the early phases of the Holocene, would

not have been possible without human activity.

Human Activity and Environmental

Conservation

During the last 500 years, human impact on the

European environment have become much more im-

portant than the natural conditions. Particularly

Figure 10 Preliminary curve of relative sea-level change for western Pomerania, shaded area: interval of ‘data confidence’, solid

line: local trend for western Pomerania, dashed line: estimated trend, for the time span between 6000 and 4500 years BP tectonically

controlled local uplift is assumed. Note: Ages are given here in

C years BP. (From Harff J, Frischbutter A, Lampe R, and Meyer M

(2001) Sea-level change in the Baltic Sea: interrelation of climatic and geological processes. In: Gerhard LC, Harrison WE, and Hanson

BM (eds.)

Geological perspectives of global climate change. Tulsa, Oklahoma, American Association of Petroleum Geologists in collabor-

ation with the Kansas Geological Survey and the AAPG Division of Environmental Geosciences: 231–250. Reprinted by permission of

the AAPG whose permission is required for further use.)

154 EUROPE/Holocene

within the last hundred years, industrial methods in

agriculture have resulted in a widespread conversion

of natural habitats into farming land. Accelerated

human-induced soil loss has become a major prob-

lem. Measures initiated to solve the problems of

modern agriculture, for example, to protect the soil

against nutrient depletion, partly result in adverse

effects such as eutrophication.

One of the most severe impacts on environment

is connected with the beginning of industrialisation.

Natural resources which had accumulated over mil-

lions of years have been exploited within decades or

less. Large industrial facilities have been built on ter-

rain of formerly less affected landscapes. Moreover,

military needs have modified great parts of the ter-

rain. Growing populations all over Europe have

enhanced the conversion of natural habitats into

settlement areas. At the same time, the management

of industrial and municipal waste has become a major

issue. The effects of industrialisation are reflected by

many proxies such as the concentration of heavy

metals in sub-recent deposits (Figure 12).

All these tendencies have developed ideas on nature

conservation, sometimes with the idealistic approach

of going back to a state where human influence is

negligible. Nature conservation in this context may

be regarded as a contradiction in itself because it

does not recognise the vital role of human society

for the natural environment. Large areas along the

Netherlands’s coast would have been flooded if the

coast was not protected by coastal engineering. Fur-

thermore, the dynamic character of the environmen-

tal status must be considered. For the last 8000 years

of the Baltic Sea’s history it can be shown, for exam-

ple, that high nutrient levels already existed immedi-

ately after the Littorina Transgression. Without any

remarkable human influence, organic substances and

nutrients could accumulate in the sediments because

of restricted vertical convection. This process has

been intensified during the last centuries and decades

by agriculture and the industrial release of nutrients

(Figure 13). Thus, if the Helsinki Commission for the

protection of the Baltic Sea aims to restore the eu-

trophication level of the 1950s, it must be stated

that that was just one time slice of the Baltic Sea’s

Holocene development. One might be successful in re-

establishing the concentrations of certain nutrients,

but it would be in a completely different new context.

As human society develops further, it cannot be

expected that there will be no response by the natural

environment. A certain equilibrium, including the

benefit for as many species as possible including

Figure 11 Europe about 4500 years BP. (From Andersen BG and Borns HW (1994) The ice age world: an introduction to Quaternary history

and research with emphasis on North America and Europe during the last 2.5 million years

. Oslo: Scandinavian University Press, with

permission.)

EUROPE/Holocene 155

Figure 12 Enrichment of heavy metals within the last century, as recorded in a sediment core from the Arkona Basin (western Baltic

Sea). (From Th. Leipe, Baltic Sea Research Institute Warnemu

nde, with permission.)

Figure 13 Trends of winter phosphate concentrations in the surface layer (0–10 m) of the eastern Gotland Basin (central Baltic Sea).

(From G. Nausch, Baltic Sea Research Institute Warnemu

nde, with permission.)

156 EUROPE/Holocene

Table 1 Summary of the climatic and historical development during the European Holocene

Calendar

years BP

Environmental

Period General climatic features Selected historical events

Stages of the Baltic

Sea’s development

Modern climatic optimum, warm World War I and II Mya Sea

200 Subatlantic

French Revolution

Little Ice Age, mean annual

temperature in Europe 1



lower than today, cold winters,

but pronounced fluctuations,

glacier advances

Less brackish

400 Thirty Years’ War Mya Sea

Lymnaea Sea

Renaissance and reformation Brackish

600

Bubonic plague kills about one third

of the European population

Transition to colder conditions

800

Medieval climatic optimum, mean

annual temperature 1–1.5



higher than today, winegrowing

as far north as to the British

Isles, first dry, later wet

Brackish

Subatlantic

1000

Expansion of Norman people as far

as Iceland, Greenland, North

America and southern Russia

1200

Cold and wet period, many

glacier advances

1400

Subatlantic End of the Roman Empire Slightly brackish

1600

Invasion of the Huns forces the

emigration of nations

Lymnaea Sea

1800

2000 Roman climatic optimum, as

warm as the Medieval

optimum, mostly very wet,

towards the end more dry

Foundation of the Roman Empire

First southward migrations of

Gothic tribes

2200

Pronounced cold period, mean

annual temperature 1–1.5



lower than today, very cool

summers, very wet, large

glacier advances

Celtic La Te

ne culture in big

parts of Europe

2400

Beginning of the Greek classic period

Formation of the Roman Republic

2600 Celtic Hallstatt culture in central and

western

Subatlantic Europe introduces the iron age

Subboreal Greek Archaic period

2800

3000 First Celtic tribes in eastern and

central Europe

Brackish

3200

(Continued)

EUROPE/Holocene 157

Predominantly warm with Distinct

fluctuations, less precipitation

than during Subatlantic

Urn field culture in central and

South-eastern Europe

3400

First bloom of the Mycene culture in

Greece

3600

Beginning of the Bronze Age in

northern Europe

3800 Subboreal

Cold period with glacier

advances, initially dry,

later more wet

4000

4200 In Europe exists an extensive trade

route network

4400

Early Minoic culture at Crete Island

launches the European Bronze Age

4600

4800

5000 Increasing influence of Indo-European

people all over Europe

5200 Introduction of the wheel in Europe

5400 Megalithic monuments in many regions

of central and western Europe

Brackish

5600 Subboreal

5800 Atlantic

6000 Narva-culture in North-eastern Europe

6200 Rapid increase of humidity in

eastern central Europe

First stone buildings at the Orkney

Islands

6400 First Neolithic settlements at the

British Isles

Warm period, mean annual

temperatures 2–3



C warmer

than today, especially warm

winters, very moist, former

predominant pines are

replaced in the forests by oaks,

lime and hazel

6600

Late Mesolithic Ertebølle - culture

in northern central Europe

6800

7000 Neolithic Karanovo – culture in

South-eastern Europe

7200 Late Mesolithic Ertebo

lle culture in

northern Europe

7400 Neolithic ‘Bandkeramik’ – culture in the

Loess areas of central Europe

7600 Strongly brackish

7800

Mesolithic Kongemose culture in

northern Europe

Littorina Sea

8000

(Continued)

Table 1 Continued

Calendar

years BP

Environmental

Period General climatic features Selected historical events

Stages of the Baltic

Sea’s development

158 EUROPE/Holocene

mankind is desirable. Closed production cycles might

be one of the important targets to achieve this.

Actualism in a New Context

The special character of the Holocene as a period

which is not only part of the geological past but also

an interface with the future, gives the principle of

actualism a new dimension. In addition to regarding

the present as being the key to the past, past and

present times might be regarded as a key to the future.

Predictions of future developments become more and

more important to cope with possible changes in

the natural environment. For this purpose, detailed

knowledge about similar processes in the past is

indispensable. In order to calibrate proxies from the

geological record, it is necessary to analyse recent

proxies by comparison with older ones, and also the

Table 1 Continued

Calendar

years BP

Environmental

Period General climatic features Selected historical events

Stages of the Baltic

Sea’s development

Short lived cold interval, drop of

the mean annual temperature

by 2



Ancylus Lake

8200 First Neolithic agricultural societies in

South-eastern Europe and Greece

Freshwater

8400

The English Channel separates

the British

8600 Slightly warmer and moister

than today

Isles from the continent

8800

9000 Atlantic Hunter and gatherer societies

Boreal Cold phase in the Carpathian

Basin

9200

During summers generally

warmer than today, mainly

open winters

Maglemose-culture in northern Europe

9400

Azilian culture in western Europe

9600

Microliths become common

9800

Use of log-boats is proven

10000

10200 Boreal

Preboreal Nomadic hunters arrive in England

10400

Ahrensburg culture in northern Germany

Freshwater

10600

Summers as warm as today,

but very cold winters

10800 Ancylus Lake

Yoldia Sea

11000 Freshwater

11200 Regionally

brackish

11400 Quick warming Bromme culture in Denmark

Freshwater

11600 Preboreal Beginning of the Holocene Mesolithic Yoldia Sea

Younger Dryas End of the Pleistocene Palaeolithic Baltic Ice Lake

11800

12000 Cold period, mean annual

temperatures by 5–9



lower than today

Freshwater

EUROPE/Holocene 159

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