6.1.1
what are fossils
preserved remains or traces of living things formed when organisms dies and is buried in sedimentary rock
What is relative age
The age of a rock compared to other ages of rocks
what four major things are used to separate the geological time scale
Eons, Eras, Periods, and Epochs
what separates into continents & oceans began to form
what is pangea?
What was the ocean like on early earth
Water evaporates and surface is too hot
What is a Paleontologists
Scientists who study, collect and classify fossils
What is absolute age
The age of the rock ever since it was formed
what are the three eras in the phranozoic era
Paleozoic era, Mesozoic era, and Cenozoic era
The Paleozoic era is the age of what?
what are invertebrates?
what were oceans like on precambrian earth
earth cools, water vapor condenses.
What are the five fossil types
trace fossil, cast, mold, petrified fossil, and carbon film
What is the law of superposition
In horizontal sedimentary rock layers, the oldest layer of rocks is at the bottom and the youngest layer is at the top
roughly 4.6 billion years ago
what was 400,000 years ago?
what was the atmosphere like on early earth
Contained hydrogen and helium
Sedimentary rock
What is Radioactive Dating
The amount of radioactive element in a rock is used to determine the absolute age of rocks
What is the geological time scale
Earth's history divided into four major subdivisions
New grasses and flowering plants dominated
land
what was the atmosphere on late precambrian earth like
volcanoes released nitrogen, water vapor, and carbon dioxide
What is a fossil record
Information gathered by paleontologists which provides evidence
What are Index Fossils
Widely distributed fossils that represent a type of organism that existed only briefly
Why was the precambrian so important to earth's history
It is about 88% of earth's history
What era did mountain ranges form?
What's the Cenozoic era?
what was the continents like on late precambrian earth
new continents started to form as a result in continental drifting