8th First Nine Weeks Study Guide
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Friedrich Mohs invented a system to describe and compare hardness of minerals
A vein is a narrow channel or slab of a mineral that is sharply different from the surrounding
rock
The purpose of heating iron ore to a very high temperature in a blast furnace is to heat the iron
so that it separates from other elements in the ore
Hard, colorful minerals that have a brilliant or glassy luster are gemstones
Steel is an example of a useful alloy
A mineral that splits apart easily along flat surfaces has the property called cleavage
Color alone cannot be used to identify a mineral because only a few minerals always have their
own characteristic color
Earthy, shiny, waxy, metallic, and pearly are terms used to describe a minerals’ luster
The size of a mineral’s crystals depends on the rate of cooling of the magma or solution from
which the mineral formed
Metallic is NOT one of the six types of crystal shapes
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Most metamorphic rock forms deep underground
A rock called a porphyry has large crystals surrounded by smaller crystals
Granite is not a sedimentary rock
The minerals that make up most of Earth’s crust are called rock-forming minerals
A rock’s texture is the look and feel of the rock
Erosion and deposition play roles in the formation of a sedimentary rock
Slate is basically a denser, more compact version of shale
Basalt is an igneous rock
The names of the three major groups of rocks refer to how the rocks formed
Chemical rocks form when minerals that are dissolved in a solution crystallize on Earth’s
surface
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Molten material erupts through a valley of mid-ocean ridge.
Alfred Wegener was the first to propose the theory of continental drift.
The transfer of energy through space is called radiation.
In the convection current of a pan of soup, the cooler, denser fluid sinks to the bottom.
Scientists who study the forces that make and shape the planet Earth are called geologists.
Earth’s lithosphere is broken into separate sections called plates.
Subduction is the process by which oceanic crust sinks beneath trenches.
Scientists rejected Wegener’s theory because he could not explain what force pushes or pulls
continents
Continental crust consists mainly of the rock granite.
A break in Earth’s crust where rocks slipped past each other is called a fault
Contour lines, on a topographic map connects points of equal elevation
A landform made up of flat or gently rolling land with low relief is a plain
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A hemisphere is one half of the sphere that makes up Earth’s surface
An index contour can be used to find the elevation of a feature on a topographic map
Landforms, relief, and elevation depend on the topography of an area
Elevation is often a main difference between a coastal plain and an interior plain
A key is a list of all of a map’s symbols
The prime meridian runs through Greenwich, England
The imaginary line that circles Earth halfway between the poles is called the equator
A map’s scale relates distance on a map to a distance on Earth’s surface