Old Earth Ministries Online Earth History Curriculum

Presented by Old Earth Ministries (We Believe in an Old Earth...and God!)

This curriculum is presented free of charge for use by homeschooling families.

NOTE: If you found this page through a search engine, please visit the intro page first.

Chapter 1 - Earth History Overview

Lesson 3: Geologic Time Scale Divisions

The geologic time scale is a living document, with changes being considered each year. You will need to memorize part of the scale in order to better understand earth's history.

The table of geologic time spans presented below agrees with the dates and nomenclature proposed by the International Commission on Stratigraphy, and uses the standard color codes of the United States Geological Survey. The time scale below is compressed, with the geologic division of "Ages" removed.

Chapter 1 - Overview

Lesson 1: The Age of the Earth

Lesson 2: Geologic Time Scale

Lesson 3: Time Scale Divisions

Lesson 4: Geology Basics Review

Lesson 5: Plate Tectonics

Lesson 6: Fossils

Lesson 7: Trace Fossils

Test

The start times are in millions of years. For example, the Hadean Eon started 4570 million years ago, or 4.57 billion years ago. The start times have been rounded, with uncertainties removed. For example, the Cambrian started at 542.0 million years ago, ± 1 million years. The ± variance is not noted in the chart.

The most important section that you will definitely have to know by heart is the Eras and Periods of the Phanerazoic Era. You do not have to memorize the whole chart for this course.

Resources

The Geological Society of America publishes a wall chart of the Geologic Time Scale. It would be very useful to anyone studying the earth's history. Click here to view and purchase the chart. Chart is 18" by 27". Cost is $9.95.

This can also be printed on a single page sheet from the GSA website.

For reference during the study of this course, we highly recommend that you print out the Geologic Time Scale published by the Geological Society of America (GSA). It can be found here.

Geologic time scale[hide]

Supereon	Eon	Era	Period	Epoch	Start, million years ago
	Phanerozoic	Cenozoic	Quaternary	Holocene	0.011430
			Quaternary	Pleistocene	2.588
			Neogene	Pliocene	5.332
			Neogene	Miocene	23.03
			Paleogene	Oligocene	33.9
				Eocene	55.8
				Paleocene	65.5
		Mesozoic	Cretaceous	Late	99.6
			Cretaceous	Early	145.5
			Jurassic	Late	161.2
				Middle	175.6
				Early	199.6
			Triassic	Late	228.0
				Middle	245.0
				Early	251.0
		Paleozoic	Permian	Lopingian (Late)	260.4
				Guadalupian (Middle)	270.6
				Cisuralian (Early)	299.0
			Carboniferous/ Pennsylvanian	Late	303.9
				Late	306.5
				Middle	311.7
				Early	318.1
			Carboniferous/ Mississippian	Late	326.4
				Middle	345.3
				Early	359.2
			Devonian	Late	374.5
				Late	385.3
				Middle	391.8
				Middle	397.5
				Early	407.0
					411.2
					416.0
			Silurian	Pridoli	418.7
				Ludlow/Cayugan	421.3
				Ludlow/Cayugan	422.9
				Wenlock	426.2
				Wenlock	428.2
				Llandovery/ Alexandrian	436.0
					439.0
					443.7
			Ordovician	Late	445.6
				Late	460.9
				Middle	468.1
				Middle	471.8
				Early	478.6
				Early	488.3
			Cambrian	Furongian	496.0
				Furongian	501.0
				Middle	513.0
				Early	542.0
Precambrian	Proterozoic	Neoproterozoic	Ediacaran		630
			Cryogenian		850
			Tonian		1000
		Mesoproterozoic	Stenian		1200
			Ectasian		1400
			Calymmian		1600
		Paleoproterozoic	Statherian		1800
			Orosirian		2050
			Rhyacian		2300
			Siderian	.	2500
	Archean	Neoarchean			2800
		Mesoarchean			3200
		Paleoarchean			3600
		Eoarchean			3800
	Hadean	Early Imbrian			c.3850
		Nectarian			c.3920
		Basin Groups			c.4150
		Cryptic			c.4570

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