1. Explain what sedimentary rocks can tell us about our past conditions.
They can tell us the climate, organisms, and type of environment that the
Earth was in during the time period that it existed.
2. Describe what igneous intrusive and extrusive rocks are. What does it mean when they
are high/low in silica?
Intrusive igneous rock is found inside the earth from magma, which cools slowly,
and grows large crystals. Extrusive igneous rock is found outside the earth from
lava, which cools rapidly, and grows small crystals. When a rock has high amount of
silica (BOB), quartz, mica, feldspar, then the rock will be light in color and can be
very explosive inside a volcano. When the rock is low in silica, dark in color, it will
be found around gentle flowing volcanoes.
3. How are rocks different from minerals?
Minerals are the building blocks of rocks just like letters make up words. For
example, the letters B.O.B spell the word BOB just like quartz, mica, feldspar
minerals make up the rock Granite.
4. What is an unfoliated and foliated metamorphic rock?
An unfoliated metamorphic rock means that the rock has no folds or layers in it,
just one uniform color. A foliated rock is a metamorphic rock that has layers or
folds in it.
5. What are the 3 different types of rocks? Define each one.
1. Sedimentary rock is pieces of broken rock, shells, mineral grains, and other
materials that collects in layers to form rock.
The 3 types of sedimentary rock are the following:
A. Detrital- Fragments of weathered rocks compacted and cemented together.
B. Chemical- Formed when dissolved mineral come out of solution.
C. Organic- Rocks made of the remains of once-living things.
2. Metamorphic- New rocks form when existing rocks are heated and squeezed.
The 2 types of metamorphic rock:
A. Foliated- Has layers or folds
B. Nonfoliated- Has no layers or folds, 1 uniform color.
3. Igneous- Form when melted rock from inside earth cools.
The types of igneous rosk:
A. Extrusive- Melted rock that cools on the earth’s surface from lava. Small
crystal sizes.
B. Intrusive- Melted rock that cools below the earth’ surface from magma.
Larger crystal sizes.
6. How do new minerals form as rock changes into metamorphic?
New minerals form through the process of heat and pressure which recrystalizes to
become a new mineral while being mixed with other elements.
7. Draw a diagram of the rock cycle. Draw arrows and describe the 4 processes that rocks
go through along with the 3 rock types.
Remember the rock cycle does not go exactly in this order, however the processes
are what a rock goes through to become the next. (Refer to page 79).