Geological Timescale Eon Era Period Ma Geological Environment in the (millions of Lake District years ago) 0 ‘Ice Age’ with 11 cold phases or Quaternary glacials 2 Cenozoic 2 Tertiary 65 65 Cretaceous 142 142 Jurassic 206 Mesozoic 206 Triassic Desert & semi-arid conditions 249 with Britain 15ºN of the Equator 249 (similar to the location of the present day Sahara desert) Permian 290 290 Equatorial climate with Britain Phanerozoic lying on the Equator giving warm (visible life) Carboniferous 354 shallow seas & on the delta areas lush tropical vegetation 354 Desert & semi-arid conditions with Britain 20ºS of the Equator Devonian 417 (similar to the location of the present day Kalahari desert) 417 Initially tropical shallow marine Silurian conditions, followed by deepening Palaeozoic 443 seas due subsidence 443 Subduction of the Iapetus Oceanic crust forming explosive Ordovician 495 volcanoes, followed by the collision of the Laurentian & Avalonian continents 495 Deposition of sediments by turbidity currents in deep water Cambrian on the continental slopes of the former Iapetus Ocean 545 545 Cryptozoic Pre-Cambrian (hidden life)
Geological Timescale Eon Era Period Ma (millions of years ago) Geological Environment in the Lake District Phanerozoic (visible life) Cenozoic Quaternary 0 2 ‘Ice Age’ with 11 cold phases or glacials Tertiary 2 65 Mesozoic Cretaceous 65 142 Jurassic 142 206 Triassic 206 249 Desert & semi-arid conditions with Britain 15ºN of the Equator (similar to the location of the present day Sahara desert) Permian 249 290 Palaeozoic Carboniferous 290 354 Equatorial climate with Britain lying on the Equator giving warm shallow seas & on the delta areas lush tropical vegetation Devonian 354 417 Desert & semi-arid conditions with Britain 20ºS of the Equator (similar to the location of the present day Kalahari desert) Silurian 417 443 Initially tropical shallow marine conditions, followed by deepening seas due subsidence Ordovician 443 495 Subduction of the Iapetus Oceanic crust forming explosive volcanoes, followed by the collision of the Laurentian & Avalonian continents Cambrian 495 545 Deposition of sediments by turbidity currents in deep water on the continental slopes of the former Iapetus Ocean Cryptozoic (hidden life) Pre-Cambrian 545
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