APSC 151 midterm review
Questions And Answers
Uniformitarianism
✓✓✓✓~ the theory that changes in the earth's crust during geological history have resulted
from the action of continuous and uniform processes.
Catastrophism
✓✓✓✓~ the theory that changes in the earth's crust during geological history have resulted
chiefly from sudden violent and unusual events.
Milankovitch Theory
✓✓✓✓~ a theory to explain variations in climate are a result of
1) variation in the shape of Earth's orbit around the sun;
2) changes in the angle of earths axis
relative dating
✓✓✓✓~ events are placed in order without knowing age.
,Law of Superposition
✓✓✓✓~ The geologic principle that states that in horizontal layers of sedimentary rock,
each layer is older than the layer above it and younger than the layer below it.
**OLDER LAYERS ARE LOWER**
Principle of Original Horizontality
✓✓✓✓~ Sediments are originally deposited in flat horizontal layers. (layers with folds have
been disturbed)
principle of cross-cutting relationships
✓✓✓✓~ younger features cut across older features (ex a dyke/fault cutting across sediment
layers)
Lithosphere
✓✓✓✓~ the rigid outer part of the earth, consisting of the crust and upper mantle. Makes up
tectonic plates
Asthenosphere
✓✓✓✓~ plastic solid layer below the lithosphere. Subdivision of the mantle
Mesosphere
, ✓✓✓✓~ Lower part of the mantle between the asthenosphere and the core. more liquidy
than asthenosphere.
Core
✓✓✓✓~ Inner most layer of earth. Liquid outer portion, solid inner portion. composed of
mainly iron and nickel
Expanses of time (4 biggest to smallest)
✓✓✓✓~ 1) Eon
2) Era
3) Period
4) Epoch
Hadeon Eon
✓✓✓✓~ The earliest period in Earth's history (4.5 to 3.8 billion years ago), unstable crust,
no life
Archaen Eon
✓✓✓✓~ 3.8 - 2.5 billion years ago, constant volcanic activity, no continents, atmosphere of
methane, bacteria begin to produce oxygen
Questions And Answers
Uniformitarianism
✓✓✓✓~ the theory that changes in the earth's crust during geological history have resulted
from the action of continuous and uniform processes.
Catastrophism
✓✓✓✓~ the theory that changes in the earth's crust during geological history have resulted
chiefly from sudden violent and unusual events.
Milankovitch Theory
✓✓✓✓~ a theory to explain variations in climate are a result of
1) variation in the shape of Earth's orbit around the sun;
2) changes in the angle of earths axis
relative dating
✓✓✓✓~ events are placed in order without knowing age.
,Law of Superposition
✓✓✓✓~ The geologic principle that states that in horizontal layers of sedimentary rock,
each layer is older than the layer above it and younger than the layer below it.
**OLDER LAYERS ARE LOWER**
Principle of Original Horizontality
✓✓✓✓~ Sediments are originally deposited in flat horizontal layers. (layers with folds have
been disturbed)
principle of cross-cutting relationships
✓✓✓✓~ younger features cut across older features (ex a dyke/fault cutting across sediment
layers)
Lithosphere
✓✓✓✓~ the rigid outer part of the earth, consisting of the crust and upper mantle. Makes up
tectonic plates
Asthenosphere
✓✓✓✓~ plastic solid layer below the lithosphere. Subdivision of the mantle
Mesosphere
, ✓✓✓✓~ Lower part of the mantle between the asthenosphere and the core. more liquidy
than asthenosphere.
Core
✓✓✓✓~ Inner most layer of earth. Liquid outer portion, solid inner portion. composed of
mainly iron and nickel
Expanses of time (4 biggest to smallest)
✓✓✓✓~ 1) Eon
2) Era
3) Period
4) Epoch
Hadeon Eon
✓✓✓✓~ The earliest period in Earth's history (4.5 to 3.8 billion years ago), unstable crust,
no life
Archaen Eon
✓✓✓✓~ 3.8 - 2.5 billion years ago, constant volcanic activity, no continents, atmosphere of
methane, bacteria begin to produce oxygen
