50 terms

Chapter 12 Study Guide (note-taking)- Science

Section 1: Surface water
runoff- rain water tthat ____________________
flows across earth's surface;
amount of runoff is affected by several factors
amount of rain, length of time it falls, steepness (slope) of the land, and the amount of vegitation
Erosion- the wearing away of soil and rock by _____
rill erosion- during a heavy rain, a small ______ forms and carrys away soil creating a groove called a channel
gully erosion-
heavy rains remove large amounts of soil and sediment from a rill channel, forming a gully
sheet erosion- ______ of water flowing across the land pick up and carry away sediments
______ erosion- water in a stream picks up sediments from the bottom and the sides of iyts channel, making the channel deeper and wider1=
river system- the network groundwater and streams that come togther to from a _____
___________________- the area of land from which a stream or river collects runoff
Drainage basin
_______________ River drainage basin- largest in the US
Stages of stream development
Young stream- flows swiftly through a steep valley
may have whitewater rapids and waterfalls; erodes the stream bottom faster that the sides
Mature stream- flows smoothly through its valley
erodes more on its sides; curves called meanders form; carves a broad and flat valley floor called a floodplain
Old stream-
flows smoothly through a floodplain it has carved
Flooding- when too much water enters a river system, it overflows its banks
dams- built to control the flow of water downstream/ levees- mounds of the earth built around the sides of a river toto prevent flooding
when water slows down it drops, or deposits, the sediment it is carrying
fan-shaped area formed by sediments that are deposited as water empties into an ocean or lake
Alluvial fan
fan-shaped area formed by sediments deposited as water empties from a mountain valley onto a flat open plain
Section 2
Groundwater- water that soaks into the earth and collects in the pores of the ____ underlying the soil
__% of all freshwater exists underground
soil and rock are _________ if water can pass through the pore spaces EX: _________
permeable/ sandstone
soil ansd rock are ___________ if water cannot pass through them EX: granite
_______- a layer of permeable rock that lets water move freely
zone of ____________- the area wher all pores in rock are filled with water
water table
upper surface of zone of saturation
many people get their water from groundwater through _____
groundwater flows into a well, and a ____ brings it to the surface
good wells extend deep into the __________________, past the water table
zone of saturation
wells can ______ during dry seasons or if the demand is too high
go dry
Artesian well-
water rises to surface under pressure
the watre table is so close to the surface that the water flows out
a hot springthat erupts periodically, shooting water and steam ito the air
groundwater can mix w/ ________________ to form carbonic acid
carbon dioxide
acidic groundwater moves through cracks in limestone, _____________ the rock
gradually the cracks in the rock enlarge until a _____ is formed
calcuim carbonate deposits that hand from a cave's ceiling
calcuim carbonate deposits that form od a cave's floor
if underground rock id disolved near the surface, a ________ mite form
SEction 3
ocean shoreline
shoreline forces-
3 major forces constantly change the shape of the shoreline
waves pound against shores, breaking rocks into smaller peices
move large amounts of sediment/ colide with thw shore at angles creating longshore currents, which act as rivers of sand in the ocean
currents move sediment _____ the shoreline
______ carry sediment out to the sea and bring in new sediment
rocky shorelines-
steeop shorelines
rocks and _______ are the most common feature
softer rocks erode awat ______ harder rocks, leaving islands of harder rocks
beaches- deposits of sediments that are parrallel to the shore
made of rock and shell fragments/ fragile because longshore surrents consatantly carry sand down the shore to form barrier islands, spits, sandbars, and baymouth bars/
barrier islands
fragile sand deposits that parallel the shore but are seperated from the mainland