GEO 155 1st Edition Final Exam Study Guide Lectures 18 26 Week One Questions 1 What are the various layers that make up the Earth 2 Where are the elements of the Earth made 3 What are the most abundant elements in the crust 4 Define a mineral 5 Name the three processes that can happen to precipitation once it reaches the earth 6 When does groundwater occur 7 Where does water from wells come from 8 Define a drainage basin 9 What factors determine infiltration versus overland flow Answers 1 2 3 4 5 Inner core outer core mantle upper mantle crust Lithosphere Oxygen almost half silicon almost a third aluminum less than a tenth A mineral is a naturally occurring inorganic solid with definite and consistent structure Overland flow fastest movement of water over the surface of land infiltration slower movement when water enters the soil throughflow slowest movement of water parallel to overland flow but underground 6 Groundwater is when water moves deeper below the surface until it reaches open spaces cracks and occupies these spaces 7 Water table 8 It is an area of streams moving downhill connected by tributaries that all lead to the same channel 9 These factors are 1 Substrate the ground the precipitation falls on a Texture i Coarse favors infiltration ii Fine favors overland flow b Soil Depth i Shallow favors overland flow ii Deep favors infiltration 2 Topography a Steep slopes favor overland flow b Gentle slopes favor infiltration 3 Vegetation a Impedes overland flow b Protects from raindrop splash i Dense vegetation favors infiltration ii Sparse vegetation favors overland flow 4 Climate a Indirect impact i Vegetation ii Soil iii Frozen ground b Direct impact i Precipitation 1 Highly intense precipitation favors overland flow 2 Less intense precipitation favors infiltration ii Duration 1 Long duration favors overland flow 2 Short duration favors infiltration 5 Land Use a Logging takes away vegetation favors overland flow b Livestock takes away vegetation and compacts soil favors overland flow c Urbanization favors overland flow d Farming i Plowing 1 In straight rows downhill favors overland flow 2 Contour plowing across the hill favors infiltration Week Two Questions 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 What is stage What is discharge Label the axes of a hydrograph Describe the base flow flood peak lag and duration of the graph of overland flow Describe the base flow flood peak lag and duration for the graph of infiltration Which graph depicts urban area and rural area What are annual hydrographs What are ephemeral floods When does the flood peak occur in the mountains Define fluvial geomorphology What are the two methods rivers change the environment What is the difference between aggradation and degradation What are the three methods that a river carries sediment What is a stream terrace When is a stream in equilibrium How does the bank friction and water speed change with a river channel with suspended load and a 16 17 18 19 river channel with bed load What causes degradation Give an example of degradation What causes aggradation Give an example of aggradation Answers 1 Stage is how high water is 2 Discharge is the volume of a channel at a certain time It is measured in feet cubed per seconds 3 A hydrograph is the graph of a given amount of water in a river at a given time The y axis depicts discharge Q The x axis shows time T 4 Rapid hydrologic response to rainstorm results in a high flood peak water moves quickly over landscape and floods the stream channel at once Base flow is short flood peak is high the flood is large the lag is short and the duration is short 5 Slow hydrologic response to rainstorm results in a high base flow a low flood peak a long lag and a long duration 6 Similar to pre settlement rural areas have graphs resembling the graph of infiltration but they are more similar to the hydrograph of contour plowing which is in between the rapid hydrologic response graph of straight row plowing similar to the hydrograph of urban area and that for presettlement 7 How discharge changes over the course of a year 8 There is not enough water table in the desert to reach the stream channel thus there is no base flow in between floods 9 In the spring when snow melts 10 How rivers shape land forms degradation valleys form when streams wear away a landscape downward aggradation river deposits alluvium in a valley raising the landscape valleys with flat bottoms 11 Degradation is gradual while aggradation is easily eroded and the alluvium is loose 12 Bed load sediment is too large to be picked up so it just moves along the bottom of the stream suspended load particles of rock are carried by the stream and are small enough to remain suspended dissolved load rock has been dissolved and carried as solution 13 Flat shells along a valley showing its history often times constructed of layers of degradation and aggradation 14 A stream is in equilibrium when is has exactly enough energy to transport the sediment being supplied to it without eroding or depositing any of it 15 Suspended load has no friction so it flows faster and has more energy this channel is narrow and deep Bed load is affected by friction so water is slow and does not compensate for the large sediment at the bottom of the river it accumulates making the channel wide and shallow 16 Degradation is caused by greater energy than workload This is due to land uplift with gives bigger floods 17 Dams decrease workload by backing up sediment lowering energy and creating erosion past the dam due to the increase in the energy of water without sediment 18 Aggradation is caused by greater workload than energy This is due to increased sediment from the erosion on nearby slopes and decreased energy from smaller flooding 19 At the mouth of canyons water slows down and sediment is deposited in an alluvium fan Week Three Questions 1 2 3 4 5 6 7 8 9 10 11 12 13 14 What are the two key characteristics that define a glacier How do glaciers form and move How big do glaciers have to be to start moving What are the names of areas of net gain and net loss Where are glaciers most prevalent around the world What is the classic shape of a valley eroded by a glacier How are most valleys created When did the Pleistocene occur and what was it What is plucking Distinguish between glacial drift that deposits as till versus outwash What is the term for accumulation of till Describe a landform created by erosion of continental glaciation Describe that