THE GEOLOGICAL HERITAGE OF THE GEOPARK HAS RECORDED INFORMATION ON PAST CLIMATES AND ENVIRONMENTS, THE STUDY OF WHICH IS KNOWN AS PALAEOCLIMATOLOGY.
Limestone fossils bear witness to a Givetian environment similar to our modern-day coral reefs. Speleothems such as stalagmites, stalactites, flowstones and draperies form over long periods and provide a record of variations in temperature and humidity. How does the environment react to climate variations ? What does a global warming of 2°C mean for Wallonia ? Are questions that can be answered by studying the climates and environments of the past.
FIG 1 The study of limestone fossils (1A) reveals the similarity of the Givetian environment with modern-day coral barrier reefs (1B).
FIG 2 Core sampling of the « Proserpine » stalagmite. Core sampling is preferred to removal of the stalagmite as it leaves much of the geological heritage in place and has a very limited impact on the appearance of the cave.
FIG 3 Stalagmites in the Cave of Hotton (dated as 9000 years old) and in the « Père Noël » or « Father Christmas » Cave (dated as 13000 years old), both reveal that - around 9000 years ago - the area was subjected to heavy rainfall and flooded on a regular basis. This means that the weather in Belgium can be even wetter than it is nowadays ! A range of analytical methods can be used for dating and for compiling climate charts from the information provided by stalagmites.
FIG 4 Global climate record of the earth deduced from studies of marine sediments, ice and stalagmites. The planet has experienced a succession of mild (Interglacials) and cold (Glacials) periods over the last two million years.