Week 1 - Geological Time and Palaeontology Flashcards
What are Earth’s 5 major systems?
Biosphere, hydrosphere, geosphere, cryosphere, atmosphere
What are the regions within the atmosphere?
Troposphere, stratosphere, mesosphere, thermosphere, exosphere
What matter is not included in the biosphere?
decomposed matter
What are the earliest known fossils?
Stromatolites, which are layered microbial mats
What are the ranks of geological time in order from longest to shortest?
Eon, era, period, epoch, age
How many years does the phanerozoic eon cover?
~539 million
When was the Hadean Eon? What were Earth’s defining characteristics?
4.567 - 4.031 Ga
molten rock, high volcanic activity, atmosphere of CO2, H20, and S2
What major event occurred during the Hadean eon?
Earth coalesced into a planet
introduction of water.
Asteroid impact created the moon.
Accretion of Earth’s core.
Development of Magnetic field
late bombardment stage/
When was the Archean eon? What were Earth’s defining characteristics?
4.03 - 2.50 Ga
Much cooler, oceans have formed, an atmosphere mainly comprised of nitrogen, high volcanic activity, small islands but no continents, development of single-celled life.
What events occurred during the Archean eon?
First oceans,
development of DNA
first continent
banded iron formation
great oxygenation event.
When was the Proterozoic eon? What were Earth’s defining characteristics?
2.5 Ga - 538.8 Ma
Earth cools further, reduced volcanic and plate tectonic activity, continental cores form, and earth becomes highly populated with life.
What events happened during the Proterozoic eon?
Oxygen crisis
Evolution of the first eukaryotes
Earth freezes
evolution of multicellular life
ozone stabilises
WHen was Earth’s first ma
