Erosion and Deposition
I. Landforms – physical shapes of the land
a. Examples include hillsides, cliffs, and marshes
b. Wetlands – areas characterized by a high proportion of water
c. Marshes – wetlands dominated by grasses, which a swamp is designated by trees
II. Topography – Shape of the land
a. Topographic Maps are used to show topography
b. Contour lines – lines that connect all the areas that are the same height relative to sea level
c. Contour intervals – the height difference between the contour line
i. When the contour lines are closer together they represent a steeper incline
d. Stability – the more topography changes over time, the less stable that land is said to be
III. Mean, Median and Mode
a. Mean – also known as the average, is the sum of all values divided by the total number of values
b. Median – the middle value when the data is arranged in order
c. Mode – the most common value in a set of numbers
d. Places that water comes from:
i. Rain
ii. River flow from mountains
iii. Ocean waves hitting the beach
e. Flooding is when a lot of water falls or melts in a short amount of time
f. Rainfall Pattern is the typical amount of water an area receives from rain
IV. Sediments – materials that settle out of the water
a. Delta – a fan shaped area of land at a river’s mouth that bulges into the bay
b. River channel – the riverbed is carved into the land
c. Sediment is created by the earth process of weathering
d. Weathering – the process of breaking down rocks
V. Earth Processes – Dynamic actions that occur both on the earth’s surface and inside the earth
a. Erosion – when surface soil, and rock are worn away through the action of glaciers, water and wind
i. Is a destructive process because it destroys the land
b. Deposition -- the act of depositing eroded sediment in a new location
i. Is a constructive process because it builds land
VI. Scientists
a. Geologist – studies rocks, minerals and other non-living (i.e. abiotic) parts of the earth
b. Engineer – uses scientific knowledge to solve practical problems; involved in designing most items that are used in everyday life
c. Ecologist – studies the interrelations of organisms with each other and with their environment
VII. Variables – any factor that can have any number of possible values depending on the situation
a. Controlled variable – held constant (i.e. did not change) or whose impact is removed in order to analyze the relationship between other variables without interference
b. Tested variable – changed in s systematic way in order to determine its effect
c. Uncontrolled Variable – variable that is neither controlled nor tested in an experiment
VIII. Cliff Erosion
a. Cliff erosion is caused by waves and begins below the water line
b. 3 Basic Types of Erosion Control Structures:
i. Breakwaters
ii. Seawalls/ripraps
iii. Jetty