Test 2 GEL 111
according to the mohs hardness scale, what is the hardness of quartz?
7
What is the Mohs hardness scale?
A scale which rates minerals from softest (1) to hardest (10)
what happens to temperature and pressure as you go down the earths layers?
As you go down both increase
Where does magma become lava
At a volcano
what is the most abundant alkali and alkali earth metal?
Ca, K, Mg, Na
Can minerals be liquids or gases?
No, they are always solid
what is the most abundant element on earth
O
what are the second most abundant elements on earth?
Si and Br
what are hotspots?
a volcano that is not part of plate tectonics (happens anywhere)
Fe and Ni are found where...
abundant in the earth's core
what is a volcano?
any place on earth where molten material exist the crust
where does the most magma form?
asthenosphere
the smallest part of an element ( that still retains the element's properties) is called
atom
what mineral is oceanic crust composed of ?
basalt, igneous rock including black pyroxene
what is the characteristic of porphyritic rocks?
big grains are carried to the surface start intrusive and finish extrusive
Porphyritic
both big and small grains
5. Minerals that break along planes of weak bonding (flat surfaces) because of their internal structure are said to have a mineral property called
cleavage
What is the texture of granite ?
coarse grained (phaneritic)
what does halite cleave into?
cube shaped/ shoebox fragments
what is an active volcano?
currently erupting, expected to erupt again
what are two ways the asthenosphere melts?
decompression melting and "just add water"
what is an effervescence test?
diluted with HCL, the reaction might be vigorous bubbling
what is a crystal shape of a mineral?
distinctive geometric shape ( cubic/ hexagon etc.)
where does decompression melting occur?
divergent boundaries
Where do ultramafic rocks form?
divergent boundaries and hotspots
where do mafic rocks form?
divergent boundaries and hotspots
what is halite composed of?
equal proportions of Na+ Cl atoms= NaCl
What is an extinct volcano?
erupted in the past, will never erupt again
2. When lava solidifies (at or on the surface of the land), the rocks are classified as
extrusive
what kinds of rocks come from lava?
extrusive
what are the characteristics of small grains?
fast cooling found in cold envionrments form on the surface of the crust
what is the composition of rhyolite?
felsic
what are the four different rock composition for igneous rocks?
felsic intermediate mafic ultramafic
what is the texture of andesite?
fine grained ( aphanitic)
6. Minerals that break irregularly and do not break along planes of bonding are said to when they break.
fracture
what is the texture of obsidian?
glassy
10. Based on what we know about igneous rocks, what color is the mantle? (Hint: Remember that the mantle is made up of ultramafic rocks)
green
how do minerals grow?
grow best when they are unconstructed by surrounding materials
What is the structure of a mineral like?
had to have an ordered internal structure and a specific chemical composition
the resistance of a mineral to abrasion or scratching is called
hardness
What are some tests to identify minerals?
hardness- scratch test steak effervescence magnetism density
what is a dormant volcano?
hasn't erupted for a long time, but expected to erupt again ex: Mt. hood
what makes an explosive volcano?
high gas content
what is the composition of diorite?
intermediate
what minerals is the core/outer core composed of ?
interpreted to be molten and molten iron
1. Igneous rocks that form when magma solidifies deep beneath the surface of the earth are called
intrusive
what kind of rocks are created from magma?
intrusive rocks
8. The type of bonding that forms when atoms gives or receives electrons is called bonding.
ionic bond
The way light bounces off a mineral is called?
luster
what is the composition of basalt?
mafic
what is the strongest natural magnet?
magnite
cleavage
mineral breaks along a set of planes
what types of minerals are found in the earth's surface?
mineralogical diverse due to composition
fractures
minerals with no cleavage that break in rough irregular shapes
what is magma?
molten material inside the earth
what is lava?
molten material outside of the earth
what minerals are in the upper mantle?
mostly solid and consists of silicate minerals
What are the requirements to be a mineral?
must be naturally occurring, inorganic, and solid
how can a mineral achieve the perfect shape?
must grow unimpeded by surrounding materials
where do intermediate rocks form?
ocean-ocean convergent boundaries
where do felsic rocks form?
oceanic-contiental convergent boundaries
what are common types of cleavage?
one direction two perpendicular three perpendicular three non-perpendicular
8. When melting forms magma
partial melting procedures a magma that is more felsic than the source
7. An igneous rock with very coarse-grained texture in which the minerals are centimeters long is called a
pegmatite
An igneous rock composed of two distinctly different sizes of mineral crystals with a fine-grained matrix around larger crystals is said to have a(n) _______________________ texture.
porphyritic
Which of the following rock types involves dissolved gas in the magma?
pumice
What are intrusive rocks?
rocks that form inside the earth
what is an igneous rock?
rocks that form when molten material (lava/magma) cools and crystalizes into rock
what are extrusive rocks?
rocks that formed outside the earth
what is the streak test?
rub mineral against porcelain plate
what types of minerals are found in the uppermost continental crust
sedimentary rocks/ combinations of quartz
What are characteristics of mafic/utramafic volcanoes?
silicate - 44-50% low viscosity wide, flat mountains or no mountains shield, scoria cone, fissure volcano fluid eruptions fas escapes easier and no build-up
what are the characteristics of felsic/intermediate volcanoes
silicate - 60-76 % high viscosity tall mountains composite volcanic dome explsive eruptions high pressure build-up
What is the meaning of texture in geology?
size, shape, and arrangement of mineral grains in rock
what are characteristics of large grained rocks?
slow cooling form in warm environments form in side the crust
the color of a mineral in its powdered form is called?
streak
where does the "just add water" melting occur?
subduction zones ocean continental/ ocean-ocean convergent
What is decompression melting?
temperature stays the same and pressure is reduced
what does every rock have?
texture and composition
What is cleavage controlled by?
the arrangement of atoms
what does texture tell us?
the cooling history
luster
the way light bounces off of a mineral's surface
why will an extinct volcano never erupt again?
there is no molten material underneath
what is the composition of peridotite?
ultramafic
where is Mg found in the earth?
upper crust and mantle
color
useful in determining what mineral, but is not always a reliable method
what is the texture of scoria?
vesicular
what is "Just add water" melting?
water lowers the melting temperature
what does composition tell us?
where it formed and the crust type
what is composition?
which minerals make up the rock
