Rocks
This type of rock is formed when other rocks are broken into small pieces than cemented together
Sedimentary Rock
a naturally occurring, inorganic solid that has a crystal structure and a definite chemical composition.
A series of processes that change one type of rock into another type of rock
The Rock Cycle
the most common type of fossil
permineralized fossil (permineralization)
Indicates that one layer is older or younger than another layer based on surroundings, but does not indicate the rock’s actual age in years.
Relative Dating
Formed from Magma below Earth’s surface that cools and hardens into a rock, erosion brings the rock to Earth’s surface.
Intrusive Igneous Rock
streak, color, luster, cleavage, fracture
Ways to identify Minerals
The process of changing the size, shape or volume of a rock
Deformation
can provide clues about the activities of ancient organisms
trace fossils
A place where an old, eroded rock surface is in contact with a newer rock layer.
Unconformity
Created when magma or lava cools and crystallizes into a rock
Igneous Rocks
minerals that break at random with rough or jagged edges
Fracture
The process when loose sediments compact under pressure, expelling any extra water and becoming a solid rock
lithification
The fossils of organisms that were widely distributed but only lived during a short period of time are called ____
index fossils
A record of the geologic events and life forms in Earth’s history.
mineral composition, color and texture
ways to identify rocks
the particles of a mineral line up in a pattern that repeats forming a crystal.
Crystalline shape
or Crystalline Structure
The processes required to turn an igneous rock into a metamorphic rock
Heat and Pressure
Plant leaves may form a fossil called a(an) _________________________a thin layer of carbon on rock.
Carbonized Fossil
The geologic principle states that in horizontal layers of sedimentary rock, each layer is older than the layer above it and younger than the layer below it.
Law of Superposition
Forms when existing rock is changed by heat, pressure or chemical reactions
Metamorphic Rock
How Crystals are formed
(1) The cooling of hot, liquid rock called magma causes compounds to combine. Magma that cools slowly= crystals are large, Magma that cools quickly= crystals are small. Or (2) The evaporation of water that has minerals dissolved in it
The processes required to turn a metamorphic rock into a sedimentary rock
(1) Erosion
(2) Compaction
shells or other hard parts buried by sediments gradually dissolve. An empty space remains in the place that the hard part once occupied. A hollow space in sediment in the shape of an organism or part of an organism is called a __________.
Mold
sedimentary rocks, left undisturbed, will remain in horizontal layers. Therefore... scientists can assume that sedimentary rock layers that are NOT horizontal have been tilted or deformed by crustal movement that happened AFTER those layers formed
Principal of original horizontality