Unit 2 Test Flashcards
of mass extinctions
5
percentage of extinct species
99.9
no longer in existance
extinct
what do paleontologist study
fossils
What causes a mass extinction
Climate Change, VolCANOES, astroids
Evidence of volcanoes/astroids
igneous rocks/creators
positive charge
proton
negative charge
electron
no charge
neutron
What does Carbon 12 mean
Carbon has a mass number of 12
helium nucleus (2 protons and electrons) 4/2He
Alpha particle
an electron 0/-1e
Beta particle
Energy 0/0 weird Y
Gamma particle
the isotope you have before the nuclear decay
parent
the isotope you have after the nuclear decay
daughter
strongest particle
gamma
time required for a particle to reduce to half its initial value.
half-life
basic law of geochronology, stating that in any undisturbed sequence of rocks deposited in layers, the youngest layer is on top and the oldest on bottom, each layer being younger than the one beneath it and older than the one above it.
law of superposition
the science of determining the relative order of past events (i.e., the age of an object in comparison to another), without necessarily determining their absolute age, (i.e. estimated age).
relative dating
a technique used to date materials such as rocks or carbon, in which trace radioactive impurities were selectively incorporated when exactly they were formed.
radiometric
crieteria for a good index fossil
distinctive, widespread, abundant and limited in geologic time.
the idea that all continents were once connected
Pangea
Evidance for Pangea
- Fit of the Continents
- Past Climate Belts and Distribution of Fossils
- Matching Rock Types
Divergent
____________>
covergent
When plates slide pass each other
Transform
a place where an organism lives
habitat
a role an organism has in nature
niche
