46 terms

Earth Sci: 5 -Rocks

Rock Cycle, Igneous Rocks, Sedimentary Rocks, Metamorphic Rocks
A principle that geologic processes that occurred in the past can be explained by current geologic processes
Law of Superposition
The geologic principle that states that in horizontal layers of sedimentary rock, each layer is older than the layer above it and younger than the layer below it.
rock forming mineral
One of the common minerals that make up most of the rocks of Earth's crust.
A usually light-colored igneious rock that is found in continental crust.
A dark, dense, igneous rock with a fine texture, found in oceanic crust.
The particles of mineral or other rocks that give a rock its texture.
The look and feel of a rock's surface, determined by size, shape, and pattern of a rock's grain.
igneous rock
A type of rock that forms from the cooling of molten rock at or below the surface.
sedimentary rock
A type of rock that forms when particles from other rocks or the remains of plants and animals are pressed and cemented together.
metamorphic rock
A type of rock that forms from an existing rock that is changed by heat, pressure, or chemical reaction.
extrusive rock
igneous rock that froms from lava on Earth surface.
intrusive rock
Igneous rock that forms when magma hardens beneath Earth's surface.
Small, solid pieces of material that come from rocks or organisms.
The destructive process in which water or wind loosens and carries away fragments of rock.
The process by which sediment settles out of the water or wind that is carrying it.
The process by which sediments ae pressed together under their own weight.
The process by which dissolved minerals crystallize and glue particles of sediment together into one mass.
clastic rock
Sedimentary rock that forms when rock fragments are squeezed together under high pressure.
organic rock
Sedimentary rock that forms from remains of organisms deposited in thick layers.
chemical rock
Sedimentary rock that forns when minerals crystallize from a solution.
Term used to describe metamorphic rocks that have grains arranged in parallel layers or bands.
main characteristics geologists use to identify rocks
color, texture, hardness, & mineral composition
Rock with high silica content and large crystal size, light in color, and forms continental crust
Rock with low silica content, small crystal size, dark in color, and forms oceanic crust
3 main groups of rocks
sedimentary, metaphorphic,& igneous
Two main characteristics used to classify igneous rocks
texture and mineral composition
low silica
dark in color
high silica
light in color
Which igneous rock most often used for building material?
order of formation of sedimentary rock
1. erosion 2. deposition 3. compaction 4. cementation
3 major types of sedimentary rock
clastic, organic, chemical
2 types of sedimentary rock that forms from living organisms
Coal and Limestone
How is organic limestone formed?
is a type of rock that is made up of bits of animal shells. Over millions of years these shells collected on the ocean floor. As layers of shells and mud built up, the lower layers slowly hardened into limestone.
process that causes deposits of chemical sedimentary rocks like micrite and rock salt to form
4 examples of clastic rock
breccia, shale, sand stone, conglomerate
uses for sedimentary rock
cement, salt, chalk, paints, fuel, building materials
What processes cause the formation of metamorphic rocks?
Heat, Pressure and Chemical fluids
How do geologists classify metamorphic rocks?
by the arrangements of the grains that make up the rocks (foliated or nonfoliated) and parent material
How are metamorphic rocks used?
building materials and sculptures (marble)
Metamorphic rocks that have their grains arranged in parallel layers or ands are said to be ____________.
Examples of foliated metamorphic rocks
slate (most common), schist and gneiss
Examples of nonfoliated metamorphic rocks
marble and quartzite - they do not split into layers.
Granite (igneous) + heat and pressure = this metamoprhic rock
Gneiss (metamorphic, folicated)
Sandstone (sedimentary) + heat and pressure = this metamorphic rock
Quartzite (metamorphic, nonfoliated)
Shale (sedimentary) + heat and pressure = this metamorphic rock
Slate (metamorphic, foliated)
The Rock Cycle
the processes by which, over many years, Earth's materials form and change back and forth among igneous rocks, sedimentary rocks, and metamorphic rocks