Earth science Flashcards
is a naturally occurring solid
mixture of one or more minerals, or
organic matter
rock
are classified by how they are
formed, their composition, and
texture
Rocks
Rocks change over time through the
rock cycle
Igneous rock begins as
magma.
Magma can form:
- When rock is heated
- When pressure is released
- When rock changes composition
- Magma freezes between
700 °C and 1,250 °C
Magma is a mixture of
many minerals
light colored rocks that are rich in
elements such as aluminum, potassium, silicon,
and sodium
*Felsic:
dark colored rocks that are rich in
calcium, iron, and magnesium, poor in silicon
Mafic:
takes longer to cool, giving
mineral crystals more time to grow
*Coarse-grained:
cools quickly with little to no
crystals
*Fine-grained:
magma
pushes into surrounding rock
below the Earth’s surface
Intrusive Igneous Rocks:
forms when
magma erupts onto the Earth’s
surface (lava), cools quickly with
very small or no crystals formed
Extrusive Rocks:
is formed by erosion
Sedimentary rock
are deposited in
layers, with the older ones
on the bottom
Sediments
Sedimentary Rocks are formed at or
near the
Earth’s surface
layers of rock
Strata –
the process in
which sedimentary rocks are
arranged in layers
Stratification –
made of fragments of rock cemented
together with calcite or quartz
Clastic –
is a term most often used for clastic
sedimentary rocks that are composed of
large angular fragments
Breccia
minerals
crystallize out of solution to become rock
Non- Clastic (Chemical sedimentary) –
remains
of plants and animals
Non-clastic (Organic sedimentary) –
is an organic sedimentary rock
that forms from the accumulation
and preservation of plant materials,
usually in a swamp environment.
Coal
is a sedimentary rock
composed primarily of calcium
carbonate (CaCO3
) in the form of the
mineral calcite. It most commonly
forms in clear, warm, shallow marine
waters.
Limestone
happens when rock is heated up by an
intrusion of hot magma.
Contact Metamorphism –
often called thermal
metamorphism
Contact Metamorphism
reactions driven primarily by ________________associated with the injection or extrusion of a
magma or a lava
temperature at relatively low
pressures
is a fine-grained
non-foliated
metamorphic rock
produced by contact
metamorphism
Hornfels
no discernible source of
heat (no nearby magma
chamber, for example) -
with increasing depth
the temperature and
pressure increase.
Regional Metamorphism
-
contain aligned grains of flat minerals
Foliated
is foliated
metamorphic rock that has
a banded appearance and is
made up of granular mineral
grains.
Gneiss
mineral grains are not arranged in
plains or bands
Non-Foliated –
is a non-foliated
metamorphic rock that is
produced from the
metamorphism of limestone.
Marble
they are not made by humans (they are
formed by the earth).
naturally occuring
they have never been alive
and are not made of plants or animals.
inorganic
they have never been alive
and are not made of plants or animals.
Definite chemical composition/
specific chemical structure
they have an ordered atomic arrangement.
The chemical elements that make up each mineral are
arranged in a particular way - this is why minerals “grow” as
crystals.
Crystal shape/
crystal system
are not always cube shaped! There
are many that are shaped like octahedrons (eight
faces), and some that are shaped like
dodecahedrons (10 faces).
Cubic crystals
are often shaped like
rhombic prisms or dipyramids (two pyramids
stuck together). They often look a bit like
tetragonal crystals except that they are not
square in cross section (when you look at the
crystal on end).
Orthorhombic crystals
are shaped like cubic
crystals but are longer in one direction making
shapes like double pyramids and prisms.
Tetragonal crystals
often look like six-sided
prisms. When you look at the crystal on end, it
looks like a hexagon shape in cross section.
Hexagonal crystals
look like tetragonal
crystals that have been skewed. They
often form prism shapes and double pyramids.
Monoclinic crystals
are sometimes very
strange shapes! They are usually not
symmetrical from one side to the other.
Triclinic crystals
Some minerals have ________ in them which can
oxidize or rust when exposed to the weather.
metals
Some minerals have metals in them which can
oxidize or rust when exposed to the __________
weather.
describes the way a mineral reflects light.
Luster
is when a mineral breaks on a
smooth, definite surface.
Cleavage
is when a mineral breaks
unevenly or with a rough break.
Fracture
This characteristic relates to
the mineral’s density.
gravity
is
useful in determining specific
gravity
Water displacement
split the light into two different
rays which gives the illusion of
double vision
Birefringent minerals
Some minerals display what is called the
phenomenon of __________. This basically
means that they “glow” when exposed to UV light
(black light). The mineral fluorite is often strongly
fluorescent.
photoluminescence
