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Part 1:Water Cycle and Ground Water Add the Yellow words to your note packet. A. Water Cycle - condensation- water vapor (gas) turns to liquid - deposition- 1. water vapor (gas) turns to solid - sublimation- 2. when solid water turns into water vapor -_________________solid or liquid water that falls to the precipitation Earth’s surface (one of four things an happen to it). a. ________________water that is stored on the land storage surface as ice or snow. b. ________________water that seeps into the earth infiltration and becomes subsurface water. runoff c. ________________water that flows on the surface of the land. d. evapotranspiration- evaporation of water from large bodies of water and plants The Water Cycle Amount of plants controls transpiration Evaporation is controlled by temperature A. Water Cycle regolith- soil and rocks at the Earth surface above the bedrock. Zone of saturation ________________________area where the pores between solid particles are filled with water. Zone of aeration ________________________area where the spaces are partly filled with water. Water table ________________________where the two zones meet. - water under the water table is called ground water. Zones of Soil Water B. Factors Affecting Infiltration 1. Slope of the land- steeper the slope (gradient) the less the infiltration. 2. The degree of saturation of the regolith- the more saturated the soil already is, the less the infiltration. B. Factors Affecting Infiltration 3. The porosity of the regolith porosity- is the percentage of open space in a material compared to its total volume. Generally, the greater the porosity the greater the infiltration factors affecting porosity a. shaperound has greater porosity than angular b. packing- loosely packed have greater porosity than closely packed. sorted has greater porosity than unsorted c. sortingparticle size has no effect on porosity B. Factors Affecting Infiltration permeability 4. __________________the ability of a material to allow fluids, such as water, to pass through it. - permeability rate- the speed at which fluids will flow through a material. - a material can be porous but impermeable (not permeable), if the spaces aren’t connected due to tight packing or cemented particles - If soil is loosely packed the larger the size of the soil particles the faster the permeability rate. B. Factors Affecting Infiltration 5. capillarity- attractive force between water and soil particles that prevents some of the water from moving downward. - smaller particle size the greater the capillarity. Capillary water - ____________________water that is stored in some of the small openings in the zone of aeration. C. Factors Affecting Runoff and Stream Discharge Runoff occurs when 1. rate of precipitation exceeds the permeability rate of the earth’s surface. 2. the regolith pore space is saturated 3. the slope of the surface is too great to allow infiltration to occur. C. Factors Affecting Runoff and Stream Discharge Stream discharge- volume of water flowing past a certain spot in a stream in a specific amount of time. - most runoff gets into streams and as runoff increases, discharge increases Water Pollution Two main types: point source – pollution from a single point of origin i.e. improper sewage systems, industrial waste. Nonpoint source – pollution from widely spread areas i.e. rainwater that carries pesticides and fertilizers, runoff from roads and parking lots. Weathering - chemical and physical breakdown of rocks on or at the Earth’s surface into smaller fragments. - Climate is the most important factor that affects weathering. Physical Weathering Chemical Weathering A. Physical Weathering - occurs when rock is cracked, split, or broken into smaller pieces called ________________. sediments - sediments are classified by size. (boulders, cobbles, pebbles, sand, silt, clay, colloids, and dissolved particles) 1. __________________breakup of rocks by freezing Frost Action and thawing of water. - water molecule expands by 20% as it freezes Example of Frost Action A. Physical Weathering abrasion 2. __________________physical wearing down of rocks as they rub or bounce against each other. -dry windy areas, under glaciers, stream channels. 3. __________________peeling away of large sheets exfoliation of loosened material at the surface of a rock. 4. plant roots split the rocks. Called plant action Example of Exfoliation Example of Plant Action B. Chemical Weathering - occurs when rock is broken down by chemical action resulting in a change in the composition of the rock. - oxygen, rainwater, carbon dioxide, and acids produced by decaying plants and animals. oxidation 1. _______________occurs when oxygen unites chemically with minerals. - when oxygen combines with iron you get rust. Fe + O2 FeO2 Mineral - Hematite 2. _______________occurs when water unites chemically hydration with minerals. - hornblende or feldspar, unite with water, they crumble into small particles of clay. Oxidation and Abrasion B. Chemical Weathering Carbonation 3. _______________-occurs when carbon dioxide unites chemically with minerals. -when carbon dioxide is dissolved in water it forms weak carbonic acid. This acid dissolves large masses of limestone, creating caves, caverns, and other structures. CO2 + H2O H2CO3 Carbonic Acid - sink holes- Saucer shaped holes on the surface of the land are left when acid dissolves limestone in ground. Area with these sink holes is Karst topography called____________________________. - _________________grow from cave ceilings. stalactites stalagmites - _________________grow up from floor. Sink Hole Landscape B. Chemical Weathering Organic decay 4. ___________________occurs when acids, which are formed when plants and animals decay, dissolve in water. These acids dissolve rock. C. Climate and Weathering Physical- Moist climates with wide temperature ranges Chemical- Warm, moist climates (tropical like) Climate controls the type and amount of weathering Climate and Weathering List the type of weathering in the column that would allow it occur in the greatest amount. Use under water and temperature only once. Water Needs water Frost Action Temperature Does not Consistent Variable need water Temperature Temperature Abrasion* Plant Action Frost Action Exfoliation Plant Action Exfoliation Oxidation Hydration Oxidation* Hydration Carbonation *Could be both Carbonation Abrasion does not depend on temperature. D. Weathering Rate -the smaller the particles (greater surface area), the greater the weathering rate. -hard rocks weather more slowly than soft rocks. Metamorphic rocks weather the slowest, sedimentary rocks weather the fastest. - weathering occurs faster in humid climates than in dry ones. Humid – round, smooth sediments Arid – jagged, angular sediments Climate and Landscape Humid Climate Arid Climate II Soils -part of the weathered regolith in which rooted plants will grow. - made of pieces of rocks , minerals , and organic matter residual soil- soil formed by weathering of the bedrock found beneath it Soil minerals same as bedrock minerals. transported soil- soil formed from rocks that were moved to their present locations Soil minerals (different from bedrock). Basic Soil Make Up minerals air water organic matter Soil Profile -series of soil layers (more complex as soils mature) -- soil horizon- layer of soil A-horizon (topsoil)- contains organic matter and the most weathered rock, plant and animal life B-horizon (subsoil)- below A-horizon - doesn’t contain much organic matter - contains minerals that rainwater carried out of the A-horizon. C-horizon (bottom layer)- partly weathered bedrock Soil Changes as it Matures Weathering breaks up rock. Plants and organisms die to add organic matter. Rainwater carries minerals from A horizon to B horizon. Soil Profile Diagram Humus (organic matter) A Horizon - Zone of Leaching B Horizon – Zone of Accumulation C Horizon – slightly weathered bedrock (parent material) Soil Conservation Crop rotation 1. _______________________by changing the crops from year to year helps prevent depletion of nutrients. Contour plowing 2. _______________________crops are planted in rows parallel to the contours of the land. (helps prevent erosion) Strip cropping 3. _______________________low cover crops are planted between strips of other crops. (helps prevent erosion) Soil Conservation Terracing 4. ___________________series of steps cut into a hill. (helps prevent erosion) Windbreaks 5. _______________________belts of trees along the edge of farming areas. (helps prevent erosion by wind) III Erosion -the transportation of loose sediments or rocks - - Caused by gravity, running water, glaciers, wind, and waves -- the most common sediments are Transported sediments ____________________________ (rock material that has been transported from its place of origin to another location.) Residual sediments -The other sediments are ___________________________ which is weathered rock that has remained in its place of origin. A. Transported Material - are unlike the rocks on which they are deposited. abrasion - _____________grinding and hitting of one rock against another. - gravity, water, wind, and ice are the major forces, or agents, affecting the transportation of weathered material. 1. Gravity Mass Movement Animation -the primary driving force behind erosion. -pulls rocks down a slope (causes particles to be angular). - gravity causes water to flow downhill. - gravity causes glaciers to flow outward. Slow – soil creep Fast – landslide, mudslide 2. Running Water Virtual River - responsible for most erosion. - causes particles to be rounded and smooth. - carrying power- the ability of a stream to move particles of different sizes. - depends mainly on velocity - stream velocity- depends on stream discharge and gradient. Volume of the water in a stream - stream discharge- flowing past a specific point Greater discharge equals faster velocity - gradient- Steepness of the slope down which the stream is flowing Steeper gradient equals faster velocity 2. Running Water - channel shape and velocity - the velocity of a stream is generally greatest just beneath the surface near the center of the channel , where there is less friction with the banks of the river and the atmosphere. - water near the outside of a curve has greater velocity than water near the inside of the curve. - erosion takes place on the outside of the curve and deposition takes place on the inside Stream Channel and Velocity Cross section Greatest velocity Cross section Arial/Map View of a Stream Channel Meandering Stream Oxbow Lake 2. Running Water velocity and sediment size - the size of particles that can be carried by a stream increases as the velocity of the stream increases. Watch out for this scale! 2. Running Water stream load - material carried by a stream. 1. Dissolved particles in solution. 2. fine sediments of clay, silt, and colloids in suspension _________________. 3. larger sand and pebbles that are bounced , along the stream pushed , or rolled Called bed load bed. 3. Wind the greater the velocity of the wind, the larger particles it can carry. - causes particles to be frosted and angular On Mars On Earth the 4. Ice/Glaciers widespread over Northern North America. - most of New York State shows evidence of glacial erosion. - carries the largest things, boulders - cause particles to be partly rounded , with some scratches Glacial Erosion Animation Glacial Features Wave Action -Erosion and deposition cause changes in shoreline features, including beaches, sandbars, , and barrier islands. Wave action rounds sediments as a result of abrasion. -Waves approaching a shoreline move sand parallel to the shore within the zone of breaking waves. Longshore Drift Longshore drift is the movement of sediment parallel to the shore as waves strike the shoreline at an angle. Jetties- rock walls designed to protect the entrance of a harbor from sediment deposition and storm waves. Groins- walls built to protect beaches that are losing sand from longshore drifting. Jetty BreakwaterSand piles up against one jetty while the beach beside the other erodes back into the shore. Groin Groins are built perpendicular to the shore to trap moving sand and widen a beach. Animation Beach Erosion Beautiful vacation home, or costly death trap?