Wxing+&+Erosion+Review

**Lots of questions for you to atta ****ck **** on this last big wiki! Have at it! **
 * Honors Earth Science Objectives Weathering and Erosion **
 * Reminders: please use first name or ni ****ck ****name only and use any color except purple! **

__Metamorphic Rocks__ What three processes can create metamorphic rocks? **Heat, pressure, and chemically active fluids.** -rachel What are the two types of metamorphism? Explain each. 1. regional, which is over wide area, such as mountain building or mountain burial. 2. contact, which is over local areal such as groundwater or magma contact or fault zones. adriana Weathering and Erosion What’s the difference between weathering and erosion? weathering is physical breakdown and chemical breakdown alteration of rocks at or near the surface of the earth. erosion is the physical removal of material by mobile agents such as water, wind or ice. adriana Explain each of these examples of mechanical weathering: frost-wedging, root- wedging, exfoliation, slump, creep. frost wedging is repeated cycles of freezing and thawing of water represent weather. root wedging is when roots go into rocks and the rocks break. exfoliation is when there are rock cracks, erosion happens on the edges. slump is the rapid movement of the earth. creep is the slow movement of the earth. adriana **freezing in the mountains** **-widens fracture in rocks and aids process of mechanical weathering** **-outer layr of rock expands separating the slabs** **-mass wasting oncolcing downhill movement o soil and regolith-taryn** Explain each of these examples of chemical weathering: oxidation, carbonic acid, biological activity (lichens). **-CO2 dissolved in water makes carbonic acid which is ionized-taryn** o xidation (rust) rocks that contains with iron when it mixes with oxygen. biological activity or lichens use acid to break down rocks. adriana What determines the size of sediment? (clay vs. sand) **The amount of occurred weathering/erosion; the pressure exerted on the sediment; the amount of area or space occupied. -rachel** Explain differential weathering. (hoodoos) **-rock weathers away where it isnt cemented as well as other areas-taryn** What 2 forces sort sands and other sediment sizes? **wind and water -rachel** What is the relationship between the size of sand and its relative age? **Larger sand grains are usually younger, because they have had less time to become broken up. -rachel** What is the relationship between the degree of roundness of sand and its age? **Rounder sand is older, because it has been polished more by erosion processes. -rachel** What is the relationship between the degree of roundness of sand and proximity to its source area? **The farther away it is, the rounder it is.-rachel** What is soil? Be able to identify a soil by using the soil (triangular) chart. **soil is a combonation of mineral fragments and organic matter, water, and air-taryn** What 3 common soils exist? Identify them by color, environment and chemistry. **PELDAFAR-iron aluminum oxides and clays** **PEDOCAL-calcium carbonate** **LATERITE-taryn** Glaciers and Ice Ages What is a glacier and how is it formed? - **slow moving river of ice-taryn** Explain the two types of glaciation. alpine are on mountains. and continental are sheets associated with ice ages or with polar regions. adriana List a few forms of glacial abrasion seen in Michigan. **striations and grooves - Holly** Describe in pictures and words these glacial deposits seen in Michigan: erratics, moraines, kames, eskers, drumlins. (You could upload pictures that you find on the internet or draw some yourself!) erratics- boulders lying free on the ground that are different from the bedrock under it (shows that glaciers brought it there) Moraines- layers or ridges of till deposited by glaciers Kames- steep sided hills that are composed of sand and gravel eskers- ridges composed of sand and gravel made by stream flowing in tunnels beneath the ice drumlins- asymmetrical hills composed of till and found in fields -Katy In what pattern are the moraines arranged in the Lower Peninsula? What causes this? The moraines are parallel to the Great Lakes. this is caused by plate tectonics. -Katy Glaciers produce both till and stratified drift. Explain what each is and the conditions under which it forms. How were the Great Lakes formed? **glaciers that came from the northeast melted and formed the great lakes-taryn** What are some possible causes for Ice Ages? **changes in solar activity for long periods of time or milankovitch cycles-taryn** Explain the difference between how these lakes formed: kettle lakes, finger lakes, moraine-dammed lakes. How did Lake St. Clair form? **Kettle lakes: glacial ice breaking apart and melting, very shallow. Finger lakes: long and pointing upwards. Moraine-dammed: glacial runoff was dammed in so it could not escape and formed a lake, which is how Lake St. Clair was formed. -rachel** Desert erosion What is the primary erosional agent in the desert? **water-taryn** What is secondary? **Wind-Crank** Why do flash floods occur? **The caliche sand in the desert does not drain/soak up water well. -rachel** What are: ventifacts, playas?- **V-rocks with sharp edges formed by wind. P-temporary lake that dries up-taryn** What is cross-bedding? Which 2 ancient environments produce it? deserts and beaches -adriana **sand dunes turned to stone-taryn** What environment produces frosted sand? **deserts -rachel** Shoreline processes Explain how the longshore current affects beaches. What is the effect of a groin on beach sediments? **It stops longshore drift -Holly** What is the purpose of a seawall? **to reduce the effects of strong waves and prevent beach erosion -rachel** How can a dune be stabilized so that it does not migrate? **Plant grass. The roots will hold the dune in place -Holly**