Crowdly

Add to Chrome

Universities
moodle.lsu.edu

Looking for test answers and solutions? Browse our comprehensive collection of verified answers for at moodle.lsu.edu.

Get instant access to accurate answers and detailed explanations for your course questions. Our community-driven platform helps students succeed!

As magma melt cools and mafic silicate minerals crystallize out, the melt composition becomes

depleted in Fe, Mg, Ca and more abundant in Silica, Al, Na and K.

✅

more abundant in Fe, Silica, Ca and depleted in Mg, Al, and K.

❌

depleted in Fe, Silica, Ca and more abundant in Mg, Al, and K.

❌

more abundant in Fe, Mg, Ca and depleted in Silica, Al, Na and K.

❌

View this question

There are three principal ways rocks can melt. Match the correct melt formation term with its description.

Melt caused by the addition of volatiles. This type of melt generation is associated with subduction zone boundaries.

Melt caused by the increase in temperature. This type of melt generation can be associated with many settings that have magma present or also with mantle plumes and hotspots.

Melt caused by lowering the pressure, without much change to temperature. This type of melt generation is associated with divergent boundaries and with hotspots-mantle plumes.

View this question

Choose the correct igneous rock texture for the described cooling rate.

When a melt cools instantly, the resulting igneous rock will have a

When a magma cools slowly deep below the Earth's surface, the resulting igneous rock will have a

When a lava has a fast cooling rate, the resulting igneous rock will have a

View this question

Comparing the past 400,000-year record of carbon dioxide concentrations, which statement is INCORRECT?

Carbon dioxide records generally show gradual decreases and sharp/faster increases in concentrations.

Today’s carbon dioxide concentrations are the highest they have ever been in the past 400,000 years

Except for the last 50 years, carbon dioxide concentrations have gone above 320ppm more than once.

100%

View this question

Tsunamis are large waves generated by displacement of water commonly caused by earthquakes associated with

mid-ocean spreading centers

thrust faulting at continental collision zones

large strike-slip faults

100%

subduction zones

View this question

Which statement about carbonate minerals is false?

Carbonate minerals are composed of cations bonded with the carbonate ion (SiO₄) which is a silicon atom bonded with four oxygen atoms.

A special property to help identify calcite and dolomite is using the acid test; hydrochloric acid which will react and cause the mineral to fizz, effervesce.

100%

Calcite and dolomite are the two most common carbonates.

View this question

Stretching a rubber band and releasing the stress so it goes back to it unstrained state is demonstrating what type of rock deformation?

plastic deoformation

brittle deoformation

ductile deformation

elastic deformation

100%

View this question

The molecular ion that builds silicate minerals, as shown in the figure below with one silicon atom and four oxygen atoms bonded, is called

a figure of silicon atom bonded to four oxygen atoms

Calcium-carbonate tetrahedron

Silicon-carbonate octahedron

Silicon-Oxygen 'silica' tetrahedron

100%

Sulfide terahedron

View this question

The common groups of rock forming minerals are classified based on their composition. More specifically, based on the anion or anionic complex that certain cations bond with. Which pairing of mineral group and anion/anionic complex is CORRECT?

Silicates; SiO₄

Carbonates; CO₃

Halides; halogen (Cl, F, Br)

All of the above

100%

View this question

What can be concluded from the data provided in the graph below?