Erth 111 Midterm 1 Test With
Solution
What is Physical geology/dynamic earth? - ANSWER The study of the
processes of the Earth and the composition
Scientific method: - ANSWER Hypothesis: a message expressing an opinion
based on incomplete evidence
Theory: scientific ideas supported by abundant evidence. passed many tests
-failed none
Law: Statements that completely describe a specific relationship or
phenomenon
Earths Formation; - ANSWER Initially homogeneous: all same parts
Differentiation event: Heat from collision + heat when matter starts to
squeeze + heat from decay of radioactive elements results in denser iron
alloy separating out and lighter material rising
present state of differentiation:
lithosphere/lithospheric motions
Earth's Interior - ANSWER Crust: (Oceanic and Continental):
, Oceanic Crust: 7-10km thick. Top is a thin layer of clay and tiny shells..
beneath consists of basalt and below that, gabbro
Continental Crust: - ANSWER 35-40km Thick. Rock type ranges from mafic to
felsic. Continental on average less mafic (felsic to intermediate composition)
than oceanic, furthermore less dense. Oxygen = most abundant
Mantle - ANSWER 2885 Km thick layer - largest part of earth. Consists
entirely of ultramafic (dark and dense) rock called peridotite, making
peridotite most abundant rock on planet. Almost all mantle is solid rock but
its soft enough that it flows
Outer/Inner Core: - ANSWER Outer core: liquid iron alloy, this flow of iron
alloy creates magnetic field
Inner core: solid iron because of pressure
Gradients in Earth: - ANSWER Pressure and temperature both increase with
depth in the Earth. The rate at which temperature increases as depth
increases is the geothermal gradient.
Sources of energy for the earth - ANSWER Interior: 80% of energy from
decay of radioactive elements
Exterior: Sun
Solution
What is Physical geology/dynamic earth? - ANSWER The study of the
processes of the Earth and the composition
Scientific method: - ANSWER Hypothesis: a message expressing an opinion
based on incomplete evidence
Theory: scientific ideas supported by abundant evidence. passed many tests
-failed none
Law: Statements that completely describe a specific relationship or
phenomenon
Earths Formation; - ANSWER Initially homogeneous: all same parts
Differentiation event: Heat from collision + heat when matter starts to
squeeze + heat from decay of radioactive elements results in denser iron
alloy separating out and lighter material rising
present state of differentiation:
lithosphere/lithospheric motions
Earth's Interior - ANSWER Crust: (Oceanic and Continental):
, Oceanic Crust: 7-10km thick. Top is a thin layer of clay and tiny shells..
beneath consists of basalt and below that, gabbro
Continental Crust: - ANSWER 35-40km Thick. Rock type ranges from mafic to
felsic. Continental on average less mafic (felsic to intermediate composition)
than oceanic, furthermore less dense. Oxygen = most abundant
Mantle - ANSWER 2885 Km thick layer - largest part of earth. Consists
entirely of ultramafic (dark and dense) rock called peridotite, making
peridotite most abundant rock on planet. Almost all mantle is solid rock but
its soft enough that it flows
Outer/Inner Core: - ANSWER Outer core: liquid iron alloy, this flow of iron
alloy creates magnetic field
Inner core: solid iron because of pressure
Gradients in Earth: - ANSWER Pressure and temperature both increase with
depth in the Earth. The rate at which temperature increases as depth
increases is the geothermal gradient.
Sources of energy for the earth - ANSWER Interior: 80% of energy from
decay of radioactive elements
Exterior: Sun
