The Netherlands has undergone a major metamorphosis since the last ice age. The steppe plants had to make way for peat swamps, the elk for cows and the land for the sea. These milestones in recent Dutch geological history have recently been published in atlas form.
Geographically, the Netherlands is the odd one out in Europe, on the border between the continent and the sea. That has not always been the case:about 10,000 years ago you could still walk on the North Sea bed. And 8,000 years ago, Britain was the west coast of mainland Europe.
Cause? That was the post-glacial upheaval. During the Weichselian, the last ice age, there was so much ice in present-day Scandinavia that the earth's crust was pushed down a few hundred meters.
As a result, the area south of the ice sprung up the same distance. So high that the sea level fell relatively and the North Sea dried up. This glacial seesaw influenced the Dutch landscape throughout the Holocene. But tectonics were not the only determining factor in this current geological age. Climate and human influence also contributed.
9000 BC…
…the ice age had just ended a few centuries. The sea level was still several tens of meters below the current level. The Dutch landscape largely consisted of cover sand; the precursors of the Rhine and Meuse flowed in the south of the country. Due to the warming, the braided river system (with varying water discharges) slowly gave way to a meandering system. In the northeastern part of the country the moraines from the Saalian were clearly visible. The vegetation was sparse and consisted largely of steppe plants such as saxifrage.
After 9000 BC the landscape became overgrown with forests. The Stone Age was in full swing and groups of hunter-gatherers moved through the landscape, who already had dogs as 'pets'; their prey consisted of reindeer, horses, arctic foxes and snow hares.
5500 BC…
...both the sea level and the water table had risen considerably (by about 75 centimeters per century). Around 6500 BC, the present-day Netherlands had come to lie by the sea and the coast consisted of beach walls and tidal areas behind. The clay deposits from that period indicate that the tidal differences were fairly limited – only if water is 'calm' enough can fine clay particles whirl to the bottom, otherwise they will remain dissolved in the water.
The river delta of the Rhine and Meuse moved to the east and the winding river courses grew swamp forests, which largely consisted of alder trees. Due to the rising of the water table, the first low moor areas arose inland; in Southeast Groningen and Drenthe, raised bogs developed on the poorly permeable boulder clay subsoil.
The still itinerant people lived by hunting wild boars, red deer, otters, beavers, primeval cattle and moose. They also picked hazelnuts, blackberries and water nuts. Locally they started burning down pines and birches to make wood tar, which they could use, for example, to fix flint arrowheads on wooden stakes.
2750 BC…
…the coastline began to change. The sea level rose only 20 to 30 cm per century, but the supply of sand and clay was much faster. There was no longer an open, mudflat-like landscape. The beach walls started to develop into a continuous coastline with low dunes. Large low moor areas arose in the closed tidal basins. In the east, the raised moorland fed on rainwater and as a result became continuously thicker.
The hunter-gatherers had given way to farming communities. The advancing peat pushed them further and further eastwards. Arable farming and livestock farming took place on the sandy soils. Oak trees and linden trees were felled for the construction of farms and the construction of club paths.
100 AD…
… again gaps arose in the contiguous coastline, at the location of Zeeland and South Holland; the cause was a sediment shortage off the southern coast. In the middle of the Netherlands, a large lake area had been created in the previous two millennia, in the middle of the peat, which drained to the sea via the Oerij. In the first century of our era there was a breakthrough of these central lakes towards the north, creating the precursor of the Zuiderzee.
In the eastern Netherlands, the peat area was partly covered with river clay:due to increasing tree felling in Germany, the Rhine supplied more and more clay. In the Netherlands, the last primeval forest had meanwhile been felled. About 1500 years earlier, the first hamlets had arisen on high places and in the Wadden area people had built mounds to protect themselves against storm surges. Shortly before the start of the Common Era, the Romans had entered the southern Netherlands and founded the first official cities:Forum Hadriani (Voorburg) and Noviomagus (Nijmegen).
1500 AD…
…the influence of humans was already visible on a large scale. Dikes of natural material were built along the coast and the rivers (which, incidentally, could not prevent some serious flooding from occurring). In North Holland, a number of large lakes were created by peat excavations and the first polders were also created:diked areas of land within which the water management could be regulated by a sluice. Around 1400 the first windmills were already in use.
In the interior, sand drifts arose as a result of large-scale deforestation, which threatened large areas of agricultural land. Nevertheless, the forerunner of our current cultural landscape developed in the Netherlands. With the departure of large wild animals such as moose and bear, the last remnant of wild nature disappeared from our country; what remained was a man-made and managed landscape.
Anno 2011…
…the influence of humans is even more visible. Eighty years ago, the Afsluitdijk was added and where once the tidal basins were, the Randstad is now located. Our earth's crust is still springing up slightly, but that is increasing by millimeters per century – we actually don't notice it anymore.
The recently published Atlas of the Netherlands in the Holocene shows that geological history can indeed be visualized, in an attractive and scientifically sound way. Eleven atlas maps (from 9000 BC to 2000 AD) show how the Dutch landscape has developed since the last ice age. The maps have been compiled on the basis of tens of thousands of boreholes and are a good guideline for a bird's-eye view of the Dutch Holocene. The atlas has been compiled under the responsibility of TNO, Deltares and the Cultural Heritage Agency of the Netherlands.
- The world of the Holocene (Geology of the Netherlands)
- The Holocene (Nature Information)
- Soil subsidence in the Netherlands (Nature information)
- Climate Change (Knowledge Link)
- Soil archive of the Southwest Netherlands (Kennislink)
- The Netherlands:sea level, subsidence and water management (Kennislink)