Please enable JavaScript.
Coggle requires JavaScript to display documents.
Geologic Time (Hadeon Eon (occurred somewhere between 4.6 and 4.0 billion…
Geologic Time
Hadeon Eon
-
-
considered to be "initial formation", formed by collection of dusts and gases + stabilization of crust and core
heavier elements, such as iron, become the core, whereas lighter elements, such as silicon became the crust.
name is a reference to Greek God Hades, meaning "Hell"
-
-
-
no life forms exist at this time: high presence of carbon dioxide + methane + nitrogen but no oxygen
Proterozoic
-
significant/noticeable change in environment (i.e atmosphere, oceans, terrain...)
certain rocks contained elements present on all modern continents:
copper, iron, gold, uranium, and nickel
oxygen became more present in environment (less pressure), gave way to present existence of eukaryote organisms ...i.e more complex organisms
eon most visibly characterized as the period of time in which the continents began to split up (from one super continent)
-
-
-
Archean
-
eon when life first formed and is when the first sedimentary rocks appeared (as well as igneous rocks as remnants from previous eon)
came after Hadean eon, however still large amounts of volcanic flow + tectonic plates more vigorous (clashing) than today
-
life forms that existed at the time included: cyanobacteria...in general life forms were prokaryotes during this eon
-
astronomers think that at this time, there was approximately 70% of sun luminosity comparative to today, however: temperatures appeared to be very similar to those today
Phanerozoic
Subdivisions
Cenozoic
-
-
-
great period of cooling, which created the polar/arctic regions we have now
-
ongoing development/evolution of species (e.g humans, plants, bacteria...)
-
Mesozoic
-
-
-
Three periods: Triassic, Jurassic and Cretaceous
-
due to tectonic activity, Pangea began to split slowly
no polar ice caps, generally warm and dry climate
Paleozoic
first of the three eras, considered to be age of ancient life
-
Carboniferous foliage flourished during this era, which in turn is the root of most of our present day coal material
-
-
-
-
-
-