MEK Schichtenwand 2

S5 - S7 - Schichtenwand

Here you will find all texts in the exhibition area shown. 

MEK – S5 IG T3

In Lava steckt eine «atomare Stoppuhr»: In 1250 Millionen Jahren zerfällt die Hälfte der Kalium- Atome zu Argon-Gas. Aus heisser Lava verdampft das Gas. Doch bei einem Vulkanausbruch erstarrt die Lava und schliesst das Gas ein.

Später messen Forschende die Menge Argon-Gas und berechnen so den Zeitpunkt des Ausbruchs.

MEK – ST2 T2 1 – How old is a fossil?

To determine the age of a fossil, you need to know the age of the rock it is embedded in. Here, volcanic eruptions can be helpful. If a layer of volcanic ash is found during an excavation, the age of this deposit can be determined:

The ash contains a chemical fingerprint which reveals the time of the eruption – and thus also the age of the layers above and below it.

In addition, certain fossils – known as index fossils – are only found within particular layers of rock. The discovery of these characteristic fossils is sufficient to date a rock layer anywhere in the world.

MEK – ST2 T2 2 – Oil – blessing and curse from the bowels of the Earth

Unlike coal from the Carboniferous period, oil and natural gas arose, not from huge forests, but from the tiny marine plants and animals known as plankton.

Dead plankton sinking – then as now – to the bottom of the sea accumulated in thick layers of mud. Eventually, as a result of heat and pressure, these tiny organisms were transformed into the energy-rich fuel that drives – and threatens – our world today: oil.

Not only is the carbon dioxide CO2 which was bound in plankton millions of years ago released into the atmosphere again when oil is burned. In addition, innumerable oil based plastic products are creating floods of waste, polluting every corner of the Earth

MEK – ST2 T3 1

This ammonite is a typical index fossil: it only existed for a relatively short period and was widely distributed. In addition, experts can recognise its shell by unmistakable features such as the pattern of ridges and grooves.

A fossil of this kind found during an excavation clearly identifies and dates the surrounding rock layer.

MEK – ST2 T3 2

Certain ammonites underwent significant changes over a relatively short period – here, within a matter of 4.4 million years. On the basis of these changes, rock layers between two ash layers can be divided into so-called biozones. 

These are comparable worldwide, so if a layer containing the index fossils is found, the biozone can also be determined.

 

MEK – ST2 T3 3

This ash layer – solidified lava fragments – derives from a volcanic eruption. It serves as a time capsule: the radioactive substances contained within it decay at a constant rate – like the ticking of a clock.

Many millions of years later, the analysis of lava fragments can tell us when the eruption occurred

MEK – ST2 T3 4

Plankton, drifting in the sea, consists of tiny animals and algae. The latter – like all plants – use sunlight to convert carbon dioxide CO2 into sugar. In this process, they store carbon C. Carbon C is also incorporated into the tiny animals (zooplankton) that feed on algae.

As a result, plankton contains vast amounts of carbon C – the primary component of oil.

MEK – ST2 T3 5

Plastic pollutes the oceans. Grotesquely, the oil which arose from marine organisms is returning to where it originated.

Plastic waste mountains and floating garbage patches cause massive damage – whether the material is ingested by seabird chicks, which die a painful death as a result, or ends up on our own plates in the form of microplastics.

MEK – ST2 T3 6

Humanity is shaping the Earth to an unprecedented extent. What will be left from the present day in the natural archive of the Earth, marking the “human age”?

Traces of human activities can be found everywhere – in the form of the artificial stone concrete, man-made radioactivity, or evidence of industrial farming and monocultures.

Welcome to the eGuide of the NMBE

With the eGuide, you can virtually explore exhibitions in your preferred language and, in addition to the exhibition texts, discover additional information and stories about various objects in the museum.