Question | Answer |
Pangeaea | the name of the singe landmass that broke apart 200 million years ago and gave rise to today's continents |
compression | stress that squeezes rock until it folds or breaks |
tension | stress that stretches rock so that it becomes thinner in the middle |
shearing | stress that pushes a mass of rock in opposite directions |
Earthquake | the shaking of the Earth's crust, moving as a result of the plates underneath being in motion |
Richter Scale | A scale that rates seismic waves as measured by a mechanical seismograph. Used in the late 1980's, but is commonly referred to today. The scale used now is the moment magnitude scale (electronic seismograph) |
Seismic Waves | a vibration that travels through Earth carrying the energy released during an earthquake (p-waves, s-waves, and surface waves) |
Fault-Block Mountain | a mountain that forms where two normal faults lift up another block of rock |
Shield Volcanoes | a wide, gently sloping mountain made of layers of thin lava formed by quiet eruptions |
Cinder Cone Volcano | a steep, cone-shaped hill or mountain made of volcanic ash, cinders and bombs (thick lava from explosive eruptions) piled up around a volcano's opening |
Composite Volcano | a tall, cone-shaped mountain in which layers of lava alternate with layers of ash and other volcanic material |
Magma | the molten mixture of rock-forming substances, gases and water from the mantle |
crystal | the shape a mineral takes because its atoms are arranged in a definite pattern |
Moh's Scale | a scale for determining the hardness of a mineral, named after Friedrich Moh |
Silicates | any member of the largest group of minerals |
cleavage | the property of some minerals that causes them to easily break along a smooth, flat surface |
fracture | the property of some minerals that causes them to break unevenly or along a curved surface |
luster | the way minerals reflect light |
What are examples of luster? | glassy, earthly, waxy, metallic |
streak | the colored powder left behind when a mineral is rubbed against an unglazed tile |
hardness | the property of minerals in which they are tested to see how easily they can be scratched |
diamond | hardest known mineral. It can scratch all other substances and is rated a 10 on Moh's scale. |
talc | the softest known mineral that flakes easily when scratched by a fingernail. |
What is talc used in? | powders |
quartz | a mineral in the silicate family that is used in watches, computers, glass and as gemstones |
ore | a rock in which a useful metal is found that can the3n be crushed and melted to remove the useful metal |
Igneous rock | a rock that is formed from magma or lava that has cooled and hardened |
Intrusive rock | a type of igneous rock that forms when magma hardens beneath earth's surface |
extrusive rock | a type of igneous rock that forms from lava on the earth's surface |
sedimentary rock | a type of rock that forms when particles from other rocks or the remains of plants and animals are pressed together |
What are the 4 processes of sedimentary rock? | 1) erosion
2) deposition
3) compaction
4) cementation |
What is erosion? | the process in which wind or water carries away fragments of rock |
What is deposition? | the process in which fragments of rock that have been carried by erosion settle in one place |
What is compaction? | a process in which sediments are squeezed together by pressure |
What is cementation? | the process in which dissolved minerals crystallize and glue particles of sediment together |
metamorphic rock | a type of rock that forms when existing rock is changed by heat, pressure and chemical reactions into another rock |
Gneiss | a metamorphic rock that formed from granite |
Rock Cycle | the process in which rocks change into other types of rock or magma |
weather (as a verb) | to break down due to weather conditions (like erosion due to wind, water, etc) |