8th Grade Science Test 3 Flashcards
the largest group of minerals, which compose over 90% of the earth’s crust
silicates
the layer of solid rock below the soil
bedrock
the rarest, most durable, and most beautiful minerals
precious stones
substances that are found naturally in the earth and have a crystalline structure
minerals
a theory that has never been proven false
law
chemical sediments that result from the evaporation of water
evaporites
a well-known chemical sedimentary rock
limestone
a soil substance composed of decayed organisms’ particles
humus
the most famous measure of earthquake strength, which rates earthquakes on a scale of 1 to 10
Richer magnitude scale
rocks that have a smooth,glasslike texture
amorphous
earthquake zone that includes the San Andreas Fault
circum-Pacific belt
the metal that is more valuable than gold or silver
platinum
hard, round structures that form when minerals settle out of water and crystallize around a sand grain or other mineral fragment
concretions
the measure of the pull of gravity on an object
weight
the group on which a test is performed
experimental group
a volcano that will probably not erupt again
extinct
beryl that has a deep green color
emerald
the third step in the scientific method
formulate a hypothesis
the inner core of the earth is thought to be
solid
a metal mixture of iron and carbon
steel
brass is an alloy of
copper and zinc
mining that uses a rotating drum that travels down a long track while grinding coal
longwall mining
crystals are generally characterized by many flat surfaces called
faces
the most basic unit of matter
atoma
about 80% of the world’s earthquakes occur in
the circum-Pacific belt
the breakdown of organisms is known
decomposition
any piece of solid volcanic ejecta
pyroclast
type of rock formed when magma solidifies
igneous rock
type of rock formed when deposits of sand and mineral fragments are cemented together
sedimentary rock
type of rock formed when preexisting rocks are altered by heat or pressure
metamorphic rock
any mineral that contains a valuable metallic element
ore
the branch of geology that deals with the identification and classification of minerals
mineralogy
the bending or buckling of rocks under great force produces
a fold
aluminum is refined from the common mineral
bauxite
the most abundant metal in the earth’s crust
aluminum
the type of soil that contains a mixture of sand, silt, clay, and humus
loam
the change of one type of rock into a new type of rock
metamorphism
the number that compares an object’s density to the density of water
specific gravity
the study of soil
pedology
the hardest naturally occurring known substance
diamond
a mineral that remains glowing after being exposed to ultraviolet light and then placed in the dark exhibits
phosphorescence
the most common element in the earth’s crust
oxygen
a “self pumping” well
artesian well
a substance with a pH of 10
basic
the most common of all igneous rocks
basalt
igneous rock with a smooth, glasslike texture; known as “volcanic glass”
obsidian
the most common sedimentary rock
shale
rock that consists of smooth pebbles embedded in hardened sand or clay
conglomerate rock
an organic sedimentary rock that is also called a fossil fuel
coal
term that refers to the way light is reflected from the surface of a mineral crystal
luster
What do mineralogists call an element that occurs naturally in its pure form, uncombined with other elements?
native element
What is a single layer of sedimentary rock called?
stratum
What nutrient makes a plant’s fruits “firm up” properly?
phosphorus
What is another name for a bar of refined gold?
bullion
What is an alloy of iron, carbon, and nickel or chromium?
stainless steel
What are geometric structures composed of atoms or molecules in an orderly arrangement?
crystals
name the arrow zone of active volcanoes that nearly encircles the Pacific basin.
Ring of Fire
What type of lava has a smooth texture with a “ropy” appearance?
pahoehoe
What mineral test leaves a line of powder on a plate?
streak test
What are the upper layers of the ground stripped away by surface mining called?
overburden
What is the name for a substance that is composed of only one type of atom?
element
earthquake wave that vibrate at right angles to the direction of wave travel
S waves
point at which an earthquake begins
focus
weak earthquake
tremor
fastest earthquake waves
P waves
term for small earthquakes that follow an earthquake for days or even months
aftershock
rocks on either side of a fault spring back to a position of little or no strain
elastic rebound
giant sea waves
tsunamis
instrument that records and studies the vibrations from an earthquake
seismograph
point on earth’s surface directly above where an earthquake began
epicenter
