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