CH. 1 Notes (intro to geology) Flashcards
(35 cards)
Scientific study of the solid earth and diff. systems
Geology
Study of Earth materials that make up the earth internal and external that shape it
Physical geology
history of planet earth, origin featuring life through time
historical geology
key to the past is the present
uniformitarism
Scientific method
- question
- gather info. to help/ answer question
- hypothesis
- test
- reject, accept, or modify hypothesis
- use more test if needed
Nebular theory
Solar nebula consisted of hydrogen and helium in addition to microscopic dust grains
How long ago was big bang?
13.7 billion yrs ago
How old is the earth?
4.6 Billion yrs old
How does Earth form?
layers, Metals sank to center & molten rock to primitive crust
What is the order of the Solar Nebula theory?
- Solar disk forms
- outer planets (jup., sat., ura., nep., pluto?)- colder, water and gas freeze
- 13.7 bil yrs ago big bang
- small mini planets form from collision of asteroids
- inner planets (mer., ven., earth, mars)- warmer, water and gas melt, rocks crystallize
3, 1, 4, 5, 2
How did the primitive atmosphere evolve?
volcanic gas
What happened to the earliest primitive crust?
lost to erosion and geologic processes
During the “Hadean” period what were the conditions on earth?
Described as hellish conditions, earth also had lava oceans
Placing rocks and events in their proper sequence or order w/o knowing their age in years
Relative dating
Using radioactive isotopes to determine age
Absolute dating
Things that happen very rapidly is _________
Catastrophism
How is time periods split up?
Broken into periods based largely on fossils
What are external processes?
Erosion, glaciers, landslides
What are internal processes?
Magmatism, earthquakes, faults
How is ex/internal processes linked?
ex can influence in and vice versa
How are external processes powered?
By the sun
in atmosphere, hydrosphere, & earth’s surface
How are internal processes powered?
from remaining heat in the formation of earth
What are the layers by physical properties?
crust, upper mantle (solid), lower mantle (solid), outer core (liquid), inner core (solid)
What are the layers by chemical composition?
crust (silicates), mantle (silicates) core (iron & nickel)