Geology of Earth
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408 - 362 ma
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Devonian - Kents Cavern Limestone formed
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362 - 290 ma
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Carboniferous
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MESOZOIC
| 245 - 65 ma
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245 - 208 ma
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Triassic
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TERTIARY
| 65 - 1.6 ma
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Chambers and passages of Kents Cavern carved out 2 mya
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Precambrian 4600 - 570 million years ago
4600 million years ago planet earth is a glowing molten cauldron of gases. During the Pre-Cambrian period, the moon appears 4,500ma, a continental crusts takes shape by 3,000 ma. The oldest rocks in Britain are 3,300ma found in Scotland. Oxygen builds up and the ozone shield protecting the planet from solar radiation is forming 2,000ma. The pre-Cambrian ends with the planets first major ice age 700 ma and the appearance of bacteria and fungi on the planet.
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| Paleozoic 570 - 245 million years ago
570ma Scotland was part of the North American continent and close to the equator. England was much further south and colder. The first forms of life appear on the planet as marine invertebrates, including trilobites. Sea levels and temperatures are rising. The first vertebrates, animals with backbones, appear as fish by 490ma. Over 360ma most of Britain is covered by a shallow tropical sea containing coral reefs and other marine creatures. The Devonian limestone, which today surrounds Kents Cavern, is being formed by these first forms of life. By 260ma the continents are being jammed together into one large land area called Pangea allowing plants and reptiles, evolved from the fish, to migrate across the continent. Britain became a desert. The end of this period is marked by a mass extinction destroying over 96 percent of the earth's marine life and three quarters of land animals.
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| Mesozoic 245 - 65 million years ago
The Mesozoic is the age of the dinosaurs. Pangea begins to break up into separate continents creating shallow marine habitats for species to evolve. Much of Britain is covered by sea so dinosaur fossils are rare although sea life fossils can be found from this period. But the period ends abruptly 65ma with the mass extinction of all dinosaurs and three quarters of all other species. Scientists believe this to have been caused by a massive collision with an asteroid.
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| Tertiary 65 - 1.6 million years ago
During this period plants, insects and mammals dominate the planet. The continents as we know them today are formed. During this period the north Atlantic is widening with volcanic activity off the west coast of Scotland. The Alps are formed as Africa collides with Europe. At the end of the Tertiary 2ma, underground rivers are forming the passages and chambers in Kents Cavern.
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| Quaternary 1.6 million - 12,000 years ago
During this period bipedal hominids, men walking on two legs, are evolving and moving out from the African continent. Britain is being subjected to successive ice ages and warmer interglacial periods. Homo erectus is moving into Europe and by 500,000 years ago, Homo heidelberg is using the caves at Kents Cavern as shelter. Neandertal man lived in Europe about 200,000 years ago. Many flint tools from Neandertals are found in Kents Cavern. Homo sapiens is in Europe about 40,000 years ago and jaw bones found in Kents Cavern show modern man was using the caves 31,000 years ago.
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