0 Items
+64 27 7250 007

Geology: Geological Time

Introduction
To gain an understanding of the development of the Earth we can look at an evolutionary and geological timeline.
Developing a timeline provides an overall picture of how events unfolded in Earth history. The timeline links the
event with its occurrence in Earth history and provides detailed information regarding how the planet changed
and also how individual continents came to exist as they do today.

Geological Timeline

Instructions:

  1. The timeline can be constructed in any format, e.g. written, poster, electronic media.
  2. Students can work individually or in groups.
  3. From the supplied data in the table provided, construct a timeline which clearly shows the Earth’s
    history since its formation. N.B. 100Myr could be represented by 1cm.
  4. Where relevant include labelled pictures on the timeline.
  5. Once completed present the timeline to your teacher. Correctly completed timelines could be pinned to
    the classroom wall.

Evolutionary Data on the Earth
Time (millions of years ago) Event in the Earth’s History

4,600 Formation of the Earth in space.
3,800 The Earth’s crust solidifies and oceans form. Oldest known rocks.
3,500 – 2,800 First cells form. Photosynthesis begins, oxygen is released.
1,500 – 600 Multicellular organisms begin to evolve.
600 – 550 First fossils are made.
500 – 450 The first invertebrate fish evolve.
430 – 420 Algae and centipedes appear on land.
375 Sharks begin to evolve.
350 Amphibians begin to evolve.
300 Primitive insects evolve.
280 Beetles have appeared.
225 Modern ferns appear.
200 Gondwanaland begins to break apart.The first mammals appear.
90 Modern sharks have evolved.
65 Dinosaurs become extinct. Mammals begin their reign.
60-10 Various mammals and birds evolve, e.g. rabbits, monkeys, parrots.
4 Development of bipedalism.
1.5 – 1.0 Early species of man tame fire.
0.01 The first human settlements, copper is cast and pottery is fired.
0.006 The first writing appears.

Geological Data on the Earth

Era Period Time (Myr ago)


Archaeozoic 5000 – 1500
Proterozoic 1500 – 545
Paleozoic Cambrian 545 – 505
Ordovician 505 – 438
Silurian 438 – 410
Devonian 410 – 355
Carboniferous 355 – 285
Permian 285 – 245

Mesozoic Triassic 245 -208
Jurassic 208 – 144
Cretaceous 144 – 66

Cenozoic Tertiary 66 -2
Quarternary 2 -0

Notes: • Be creative with your timeline and try to combine both evolutionary and geological data.
• If posters are designed for the wall there will be some materials required, e.g. paper etc. Your
teacher will be able to assist.