Fossils Flashcards
the gaseous portion of the planet
atmosphere
the division of Earth’s history into blocks of time covering millions of years (eons, eras, periods)
Geologic Time scale
covered with or affected by a glacier
Glaciation
rocks formed by magma or lava
Igneous rocks
The fossil remains of an organism that lived in a particular geologic age, used to identify or date the rock or rock layer in which it is found
Index fossil
scientist who studies fossils and the history of life on Earth
Paleontologist
part of geologic time characterized by abundant fossil evidence, the most recent 600 million years
Phanerozoic
all geologic time prior to the Phanerozoic Eon characterized by much volcanic activity- the first 4 billion years from the beginning of earth to the phanerozoic- ending with the Cambrian explosion
Precambrian
also known as Absolute Dating, the complex procedure of calculating a most precise age of rocks and fossils (Carbon dating is a form of this)
Radiometric dating
ages of rock layers are ordered by comparing them to the layers above and below them
Relative dating
rock type that most fossils are found in
Sedimentary rocks
The continental landmasses have consistently formed, reformed, and moved over time.
True
The geological history of the Earth describes major events in Earth’s past including what kinds of rocks existed a long time ago, climate, and lifeforms
true
Based on evidence from fossils, scientists have observed life has adapted to various changes on the Earth.
true
Throughout Earth’s history, the climate has changed many times.
true
Near the end of the Precambrian, there is evidence to suggest an increase in oxygen in the atmosphere due to photosynthesis.
true
In a series of undisturbed rock layers, the oldest layers are on the bottom and the youngest layers are on the top.
law of superposition
List 3 types of information fossils and rock layers reveal about Earth’s past:
Age of rock layers and organisms
Environmental conditions
Climate
Movement of landmasses and presence of oceans
Adaptations and evolution of organisms over time
largest time unit on the geologic time scale
eon
remains or traces of organisms preserved from the geologic past
fossils
proposed supercontinent, which 200 mya began to break apart
pangea
basic unit of the geologic time scale that is a subdivision of an era
periods
theory which proposes that earth’s outer shell consists of individual plates which interact in various ways
plate tectonics
