Geologise! The Time Machine

Public summary: 

CBS Talk - Go on a journey through time with the Geologise! crew and see how the study of geology can show what happened millions of years ago.

Travel through time with Geologise! and see how geology can
Useful information
Kit List: 

Various rock samples: fulgurite, coal, sandstone, mudstone, myriapod tracks
Toy box with various toys (including toy dinosaur)
Plastic tank and trays to put the various substances in
Coloured sand and coloured play-doh and coloured liquid
Blunt knife to cut the play-doh (with knife cover)
Paper with different colours on each side

Packing Away: 

Clean up any spillages of sand
Return rock samples to the Earth Sciences department
Return any other equipment borrowed to the place of origin
Keep the rest for possible usage in other experiments


The audience enter the time-ship Geologise! and prepare to travel back in time with the presenters, one of whom has already been back in time (or that's what he says at least...) Unfortunately, the ship doesn't manage to time travel so they have to use the study of rocks to understand what happened millions of years ago.

Relative Dating:
Use layers of play-doh and different coloured sand in a tank to show the principles of stratigraphy - that layers of sediment form one on top of the other. Show how different processes can happen to the sequence of rocks to perturb the original stratigraphy, and the techniques used to unpick the chronology. Possibly inject a coloured liquid to a layer underneath to show how igneous rocks can cut across others. Show faulting (cut the play-doh using a blunt knife) and folding in the sequence to show how rocks can be offset at the surface. Get a toy dinosaur from the toy box (throwing the other soft toys carefully out behind them) and get a member of the audience to make footprints in the play-doh layer of the stratigraphy, and show how they can be preserved. Talk about unconformities and the concept of 'missing time' in relation to Hutton's Unconformity. The sand can also show varying sedimentation rates.

Absolute Dating:
All well and good being able to tell which rock was laid down first, but what time exactly did the rock form. Explain radiogenic isotope dating and the concept of half-life. Give the audience (shown on the screen with a camera, or a small group of children at the front) a piece of paper with a different colour on each side and get them to hold it up. Get half of the room after a certain amount of time to turn the cards over, and then half of the remaining group, and so on. The number of one colour relative to the other shows how old something is.

Different Environments:
The various layers of play-doh and sand can represent different rock formations found in a sample area (such as Arran, show the geological map) and each one captures a different environment. The Devonion Old Red Sandstone with large pebbles in a sandy matrix formed from an arid environment with river systems (show samples). The Carboniferous mud and coal deposits formed in a tropical environment with many trees and large insects like the myriapod (show the myriapod footprints and what can be deduced about the myriopod from this, think about fossil preservation in general). The Permian New Red Sandstone formed in a desert environment with occasional storms (show the fulgurite formed by lightning, get a child to feel the inside of it to show it has fused, shows the sandstone formed above ground).

The talk concludes with the point that you don't need to travel in time to work out what happened millions of years ago, and in fact it is more useful to look at a whole series of rocks laid down over a long period of time as it shows how things changed, rather than just a single snapshot. All this is summarised in a song play on the keyboard and sung in harmony: Geology's like travelling in time...

Risk Assessment
Date risk assesment last checked: 
Mon, 13/02/2017
Risk assesment checked by: 
Date risk assesment double checked: 
Mon, 13/02/2017
Risk assesment double-checked by: 
Risk Assessment: 
Experiment Relative Dating and Stratigraphy Faults and Folding Footprints and trace fossils Half-Life: Holding up different coloured cards Different Environments: Various rock and fossil samples Music, Sounds and Lights
Description Pour sand into a tank, then overlay with various colours of play-doh, eventually injecting a coloured liquid through the side Cut the layers of play-doh in the tank with a knife and offset them, also folding other parts Get a toy dinosaur out of the toybox (after throwing out some other toys) and get an audience member to make imprints of the dinosaur in the play-doh Get the audience to hold up pieces of paper and turn them over. Either project view of audience with a camera or get a few audience memebrs down to the front to do this Showing the samples to the audience via the projector and an audience member feeling the inside of the fulgurite Some flashing lights, occasional sounds and a song from a keyboard
  • Sand/liquid could get on the floor and make it slippy
  • Liquid could get on electrical parts
  • Knife could cut presenter or audience member if left unattended
  • Toys could hit audience members
  • Audience member could drop toy dinosaur on foot
  • Audience coming down to the front could trip
  • Audience coming down to the front could trip
  • Paper cut from turning paper over
  • Handling heavy rocks and may drop on the floor/feet
  • Audience member could cut finger on sharp parts of fulgurite
  • Loud music and bright flashing lights may cause damage to eyes and ears, or may cause seizures in people with photosensitive epilepsy.
    Action To Be Taken To Minimise Risks
  • Keep all substances within the tank and other containers, and also within a tray
  • Mop up any spillages promptly
  • Keep electrical equipment away from any liquids
  • Keep knife in a holder and make sure it is never left unattended. Concentrate when cutting
  • Throw only lightweights toys behind in a careful fashion
  • Get audience member to hold the toy dinosaur carefully in two hands and place carefully back on the table
  • Say to watch out for cables on the way to the floor and then make sure there are no cables in the demonstration area. Gaffer loose cables down if necessary
  • Say to be careful with the paper
  • Say to watch out for cables on the way to the floor and then make sure there are no cables in the demonstration area. Gaffer loose cables down if necessary
  • Hold rocks carefully in two hands and place carefully back on the table
  • Make sure the audience member just touches the smooth part and tell them to be careful
  • Keep the music at a low sound level and the lights at a low level, warning people that there will be some flashing lights
    Action To Be Taken In The Event Of An Accident
  • Call first aider in event of injury
  • Clean up spills.
  • Cordon off the spillage area and turn electrical equipment off
  • Call first aider if required Call first aider in event of injury Call first aider in event of injury. Call first aider in event of injury Call first aider in event of injury
    This experiment contains mains electrical parts, see separate risk assessment.