Environmental factors for around 484 million years ago in the Voyage area
Rock Name
Barnt Green Voicanic Formation
Lithology (appearance)
Coarse grained green tuffs, grey sandstones, purple/dark brown grits with some calcite veins and thin bedded siltstones and mudstones, which appear to have been laid down in water and were intruded by a few microdiorite dykes after their deposition.
Period
Ordovician
How old
Around 484 million years
Environment of rock formation
Shallow marine – shelf sea – resulting from marine transgression
Climate
Warm. Greenhouse Earth
Latitude
57′ S of Equator
Oxygen as percentage of atmosphere
19% (21% today)
Carbon Dioxide as parts per million of atmosphere composition
4400ppm (around 415ppm today and rising)
Maximum day time temperatures
30’C
Minimum night time temperature
15’C
Sea temperature
Warm
Weather risk
High winds. Rough seas. Lightning. Thick ash falls
Midday Sun
Very low in northern sky
UV index
2
Earthquake risk (scale 1 low risk to 9 high risk)
10
Tectonic
Violent volcanic activity – subduction of oceanic lithosphere.
Volcano risk
Severe. Ash falls. Hydrogen sulphide and toxic gasses.
Top predator
Cameyoceras
Animal Life
Lower Ordovician microfossils (acritarchs)
Plant Life
First primitive land plants
Humidity
Rainfall
Heavy
Wind
Day length
20.5 hours
Days in year
420