| A | B |
|---|
| Geology | the study of the earth's physical structure and history |
| Earth's Core | Center of the earth, a dense area of very hot metal; mainly iron mixed with nickel. |
| Mantle | A thick layer of rock surrounding the earth's core. |
| Magma | Melted rock, found in some places in the earth's mantle |
| Ring of Fire | A cirlce of volcanic mountains that surround the rim of the Pacific Ocean. |
| Volcanism | The movement of magma inside the earth. |
| Lava | Molten rock (magma) that breaks through the earth's crust. |
| Fault | A break in the earth's crust |
| Plate tectonics | Theory that the earth's surface is made of large floating plates. |
| Continental Drift Theory | Alfred Wiegerner's idea that the earth was once one continent that broke into pieces and started to separate. |
| Pangaea | The one original continent. |
| Convection | The heating and rising of plates that causes plate movement. |
| Subduction | When one plate slides under another plate. |
| Convergence | When two plates collide and push against each other. |
| Spreading | When two plates separate. |
| Faulting | When two plates slide past each other. |
| Weathering | When the earth's surface is broken down into smaller and smaller pieces. |
| Mechanical weathering | When a rock is broken apart by roots or other devices. |
| Chemical weathering | Alters the structure of a rock by chemical changes. |
| Frost wedging | When water penetrates into rock, freezes and expands, and breaks the rock into smaller pieces. |
| Erosion | Movement of weathered material |
| Three major sources of erosion | Wind, Water and Glaciers |
| Glaciers | Huge, slow-moving sheets or rivers of ice |
| loess | wind-blown deposits of mineral rich dust and silt |
| acid rain | A source of chemical weathering produced when pollution mixes with water vapor. |
| Rotation | The spinning of the earth on its axis every 24 hours. The cause of day and night. |
| Revolution | One complete orbit of the earth around the sun. It takes 365 1/4 days and causes the seasons. |
| Solstice | Dec. 21Winter Solstice June 21 Summer Solstice Sun is directly overhead at either Tropic of Cancer (June) or Capricorn (Dec.) |
| Equinox | Sept. 21 (Fall Equinox) March 21 (Spring Equinox). Sun is directly overhead at the Equator. |
| Climate | Weather patterns of an area over a prolonged period of time. |
| Weather | The condition of the bottom layer of the earth's atmosphere. |
| Atmosphere | Multi-layered band of gases and water vapor and dust above the earth. |
| Tropical zones | Region that lies between 23 1/2 degrees North and 23 1/2 degrees South Latitude. Hot year-round. |
| Temperate zones | Regions between 23 1/2 and 66 1/2 degrees North or South latitude. Wide range of temperatures. |
| Polar zones | Regions between 66 1/2 and 90 degrees (North or South Pole) latitude. Always cool or cold. |
| Coriollis effect | Bending of the wind patterns due to the earth's rotation. |
| Precipitation | All forms of water that fall from the atmosphere onto the earth's surface. |
| Humidity | Amount of water vapor in the air. |
| Hydrologic cycle | Movement of all forms of water on the earth's surface. |
| Windward | The side of the mountain or hill that faces the wind. The wettest side. |
| Leeward | The side of the mountain facing away from the wind. The drier side because it lies in the "rain shadow". |
| Fronts | When two separte air masses meet; often causing precipitation. |
| Orographic precipitation | Precipitation caused when a moist air mass is pushed up a landform, causing it to cool. |
| Frontal precipitation | When a warm and cool air mass collide, the cool air mass goes under the warm air, forcing it to rise and cool. |
| Convectional precipitation | When air is heated and rises, then cools as it reaches higher elevations. |
| Cooling of air masses | Causes precipitation because cool air cannot hold the same amount of moisture as warm air. |
| Continental climates | Regions away from large bodies of water usually have hotter summers and colder winters. |
| Factors affecting climate | Latitude, Elevation, Proximity to Large Bodies of Water, Landforms |
