Week 1: Sustainable Engineering, Geological Timescale, GeoRisk Flashcards
When was the Hadeon Eon, and what were the key events to occur during this time?
Hadeon Eon (4.5 - 4 bya)
- Unstable crust forms
- No life
- Iron/Nickel core, iron/magnesium mantle
- Moon forms
The _____ eons consists of the Hadeon, Archean, and Proterozoic Eons.
The PRECAMBRIAN eons consists of the Hadeon, Archean, and Proterozoic Eons.
The most recent eon is the ________ eon and it began just over ___ mya.
The most recent eon is the PHANEROZOIC EON and it began just over 540 mya.
State the ‘Principle of Fossil Succession’.
Fossil organisms replace each other (evolution) in a determinable order.
State the ‘Law of Superposition’.
Younger rock layers are deposited over older rock layers.
What is ‘relative dating’?
Events are placed in their proper sequence or order without knowing their age in years.
First-life coalesced in the _____ eon, ___ to ___ bya.
First-life coalesced in the ARCHAEN eon, 4 to 2.5 bya. Constant volcanic activity, no continents, atmosphere full of methan and devoid of O2.
The ________ eon began ___ bya, and housed the first major ice age and great extinction due to the rapid release of O2 into the atmosphere.
The PROTEROZOIC eon began 2.5 bya, and housed the first major ice age and great extinction due to the rapid release of O2 into the atmosphere.
The first complex life forms formed ___ mya, during the ___-______ era.
The first complex life forms formed 600 mya, during the NEO-PROTEROZOIC era.
The start of complex mobile lifeforms (including the evolution of teeth!) began in the _________ period.
The start of complex mobile lifeforms (including the evolution of teeth!) began in the CAMBRIAN period.
The second major extinction due to another ice age occurs in the __________ period ___ to ___ mya, where filter feeders like corals, brachiopods and bryozoans were top carnivores.
The second major extinction due to another ice age occurs in the ORDOVICIAN period 488 to 444 mya, where filter feeders like corals, brachiopods and bryozoans were top carnivores.
The first evidence of life on land and the stabilization of global temperatures occurs in the _______ period, ___ to ___ mya.
The first evidence of life on land and the stabilization of global temperatures occurs in the SILURIAN period, 444 to 416 mya.
Ray-finned and lobe-finned bony fish evolve into leg and land animals in the _______ period ___ to ___ mya.
Ray-finned and lobe-finned bony fish evolve into leg and land animals in the DEVONIAN period 416 to 359 mya.
Extensive forest load themselves with carbon extracted from the atmosphere in the _______ period ___ to ___ mya.
Extensive forest load themselves with carbon extracted from the atmosphere in the CARBONIFEROUS period 359 to 299 mya.
The ________ period during the _______ era, the age of the dinosaurs!
The CRETACIOUS period during the MEZOZOIC era, the age of the dinosaurs!
