EONS ONLY Flashcards
The longest time unit in the GTS
Eons
The term was coined in 1972 by geologist Preston Cloud.
Hadean eon
The period was later classified as the Priscoan period by W. Brian Harland.
Hadean Eon
The time period of this Eon is 4.6 to 4 Billion years ago
Hadean Eon
The atmosphere of this eon is Hot, thick, steamy, and full of dust and crud. Made up of mostly carbon dioxide and water vapor, with traces of nitrogen and smelly sulfur compounds.
Hadean Eon
The Geology of this Eon is Covered with oceans of liquid rock, boiling sulfur, and impact craters.
Hadean Eon
The Life forms of this eon are Small amounts of organic carbon has been found that probably may be an evidence of first life on earth.
Hadean Eon
Reason why this eon ended because of the cooling of the earth’s temperature.
Hadean Eon
It was first used in 1872, Which means the earliest geological age
Archean Eon
The time period of this eon is between 4 to 2.5 BYA
Archean Eon
The atmosphere of this eon is Comprised methane ammonia, and other gases.
Archean Eon
The atmosphere of this eon is Most of the carbon dioxide have been chemically changed into limestone and deposited at the bottom of the ocean.
Archean Eon
The geology of this eon are Formation of the continental shield rock, Small island and masses floated in the molten seas And Start of the formation of oceans
Archean Eon
The geology of this eon are Water from comets and hydrated minerals condensed in the atmosphere and fell as torrential rain, cooling the planet and filling the first oceans with liquid water.
Archean Eon
The life forms of this eon are Microscopic prokaryotes such as photosynthetic bacteria, (Cyanobacteria) Stromatolites, Single-celled archaea extremophiles
Archean Eon
What eon did Life began in the oceans about 3.5 billion to 2.8 billion years ago. (
Archean Eon
The oldest fossils ever found in Archean eon (3.5 bya). Are layered bio-chemical accretionary structures that formed in shallow water by the trapping, binding, and cementation of sedimentary grains of microorganisms.
Stromatolites
The time period of this eon is 2.5 GA to 541 MA
Proterozoic Eon
The atmosphere of this eon is Mostly nitrogen, with a little water vapor and carbon dioxide. With Free oxygen released by cyanobacteria
Proterozoic Eon
The geology of this eon is Formation of supercontinents: Rodinia and Frequent movement of earth surface ( Plate Tectonics) and continental collisions.
Proterozoic Eon
The life forms of this eon are 1.7 GA - Appearance of single celled eukaryotes.
511 MA - appearance of multicellular organism. And still only found in the ocean
Proterozoic Eon
During Proterozoic Eon the GREAT OXYGENATION EVENT happens which cause the
Extinction of many anaerobic bacteria
It belongs to the Proterozoic Eon and its Approximately 635 million to 541 million years ago
Autotrophs and soft-bodied heterotrophs
The Ediacaran Period
The first fossil presented in the ppt in The Ediacaran period
Ediacaran biota - Charnia
The second fossil presented in the ppt in The Ediacaran period
Ediacaran biota- Dickinsonia
Caused by a 250 million year lull in volcanic activity. This caused a decrease in the carbon dioxide of the atmosphere resulting in a climate cool down
Snowball earth
The term phanerozoic was first introduced by the American geologist George Halcott Chadwick (1876-1953).
Phanerozoic Eon
Because it was once believed that the life began in Cambrian, the first period of the
Phanerozoic Eon
The time period of this eon is 541 MA to present
Phanerozoic Eon
The Phanerozoic eon is the eon of abundant complex life.
It is the eon we are living in.
Phanerozoic Eon
