exam questions n answers
What are the layers of Earth? - correct answer ✔✔crust, mantle, outer core, inner core
What is each layer of the earth made of? - correct answer ✔✔mostly iron and nickel
Which are solid and which are liquid? - correct answer ✔✔solid- crust and inner core
liquid- outer core and mantle
How do oceanic and continental crusts differ? - correct answer ✔✔They differ by there rock
types. Oceanic crust is made up of dense basalt while continental crust is made up of less dense
granite.
What are the asthenosphere and lithosphere? - correct answer ✔✔-Asthenosphere- portion of
the mantle that can flow (not liquid)
-Lithosphere- all of crust plus part of upper mantle, rigid
What is the Moho? - correct answer ✔✔boundary between crust and mantle
How have scientists determined the structure and composition of the earth's interior? - correct
answer ✔✔To determine the composition of Earth's layers, scientists studied seismic data, rock
samples from the crust and mantle, meteorites, and high-pressure experiments on Earth
materials.
What are isostasy and isostatic rebound? - correct answer ✔✔-the equilibrium that exists
between parts of the earth's crust, which behaves as if it consists of blocks floating on the
,underlying mantle, rising if material (such as an ice cap) is removed and sinking if material is
deposited.
-the re-equilibration of the crust by rebounding to the level at which it "floats" again in the
mantle after a mass has been removed
What are the two most common elements in the earth's crust? - correct answer ✔✔oxygen and
silicon
What is the most common element in the earth as a whole? - correct answer ✔✔oxygen
What is a mineral? - correct answer ✔✔a naturally occurring, inorganic solid that has a crystal
structure and a definite chemical composition
How are rocks related to minerals? - correct answer ✔✔Rocks are made of minerals
What scale is used to measure mineral hardness? - correct answer ✔✔Mohs hardness scale
What are cleavage, fracture, color, streak, luster? - correct answer ✔✔-planar rock feature
-separation or break
-color
-what color powder is produced
-how light interacts
What are igneous rocks? - correct answer ✔✔Rocks formed from molten magma that has
cooled under the Earth's surface.
How are intrusive and extrusive igneous rocks formed? - correct answer ✔✔Extrusive rocks are
formed on the surface of the Earth from lava, which is magma that has emerged from
, underground. Intrusive rocks are formed from magma that cools and solidifies within the crust
of the planet
How does the crystal size differ between intrusive and extrusive rocks? - correct answer
✔✔extrusive rocks cool quickly, they only have time to form very small crystals such as basalt or
none at all. On the other hand, intrusive rocks grow larger crystals because they take longer to
cool
How does mineral composition affect the density and melting point of igneous rocks? - correct
answer ✔✔.
What are sedimentary rocks? - correct answer ✔✔formed by the deposition of material at the
Earth's surface and within bodies of water.
What is lithification? - correct answer ✔✔compaction and cementation
How are clastic sedimentary rocks formed? - correct answer ✔✔weathering, erosion,
transportation, deposition, lithification
How are chemical sedimentary rocks formed? - correct answer ✔✔They are the result of either
precipitation of solids from solutions (like salt from water) or by organic process, like shells from
marine organisms.
What are metamorphic rocks? - correct answer ✔✔The resulting rock that has been changed by
great heat and pressure.
How are they formed? - correct answer ✔✔The absence of decay, parts replaced by minerals as
they decay, preserved traces or organisms.