The Age of the Earth.docx

3 Pages
Unlock Document

Earth & Environmental Sciences
EESC 1175
Alan Kafka

TheAge of the Earth How old is the Earth? • James Ussher o Age of the Earth = 6,018 years old  Based on biblical events in the Old Testament, he found that the world was crated on October 23 , 4004 BC at 9 a.m. • Scientists’calculations o Age of the Earth = 4.6 billion years old  Based on evidence found in rocks and radiometric dating Rocks and Geological Time Scale • Oldest Rocks = 4.0 billion years old • Oldest Minerals = 4.5 billion year old • 540 million years ago (“Pre-Cambrian”)  beginning of life o The first evidence of fossilized life within rocks • Time Scale: o 14 billion years ago  The Big Bang o 3.5 to 4.0 billion years ago  earliest form of life o 100,000 years (more or less)  modern human life Anthropocene = most recent period of time in Earth history (past few hundred years) in which humans have significant global impact on the planet • Paul Crutzen Holocene = last 10,000 years since the end of the last IceAge Geologic Time: • Geochronology = the science of determining the age of rocks • Nicholas Steno (1669)  studied strata rocks to determine age o Principle of Superposition: in any sequence of “undisturbed” strata of sedimentary rocks, the oldest layer is on the bottom and the higher layers and younger o Sedimentary Rocks = rocks formed from weathered products of pre- existing rocks (sediments) that have been transported, deposited, and lithified  converted into rock • Principle of Uniformitarianism: the physical, chemical, and biological laws that operate today have also operated in the geologic past • Sequence of Geologic Events 1. Deposition 2. Folding and Uplifting 3. Erosion 4. Subsidence and Renewed Deposition RelativeAge vs.AbsoluteAge • Absolute age of the Earth  amount of time since the Earth solidified o When did the Earth cool and solidify into its present state from the hot, molten, rocky material it used to be? Methods to Estimating theAge of the Earth  Fossils and evolution  Rates of deposition of sediments  Cooling of the Earth from a molten state  Radiometric Dating Principle of Parsimony • Oscam’s Razor • Fossils  remains of ancient life o Charles Lyell (mid-1800s): used evolution to estimate absolute ages of rocks  He needed to find a natural process that leaves a tangible record in the rocks
More Less

Related notes for EESC 1175

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.