Page 313 - Laboratory Manual in Physical Geology

BIG IDEAS PRE-LAB VIDEO

Streams shape the landscape and provide water to
communities and agricultural systems. Flood hazards
and mass wasting are also associated with streams. Tools
and methods for determining flood hazards are provided
by the Federal Emergency Management Agency (FEMA).

FOCUS YOUR INQUIRY
THINK | How are you affected by streams?
About It

ACTIVITY 11.1 Streamer Inquiry (p. 284 )
THINK | How does stream erosion shape the landscape?
About It

ACTIVITY 11.2 Introduction to Stream Processes and
Landscapes (p. 284 )

ACTIVITY 11.3 Escarpments and Stream Terraces (p. 284 )

ACTIVITY 11.4 Meander Evolution on the Rio Grande
(p. 284 )
ACTIVITY 11.5 Mass Wastage at Niagara Falls (p. 292 )

|
THINK How do geologists determine the risk of flooding
About It along rivers and streams?
ACTIVITY 11.6 Flood Hazard Mapping, Assessment,
1 11 and Risk (p. 295 )

L A B O R A T O R Y Introduction
It all starts with a single raindrop, then another, and another.
As water drenches the landscape, some soaks into the ground
Stream Processes, and becomes groundwater . Some flows over the ground and

into streams and ponds of surface water. The streams will
continue to flow for as long as they receive a water supply
Landscapes, Mass from additional rain, melting snow, or base flow
(groundwater that seeps into a stream via porous rocks,
Wastage, and fractures, and springs).
Perennial streams flow continuously throughout the
year and are represented on topographic maps as blue lines.
Flood Hazards Intermittent streams flow only at certain times of the year,
such as rainy seasons or when snow melts in the spring.
They are represented on topographic maps as blue line
C O NTRIBUTING A UTH O RS segments separated by blue dots (three blue dots between
Pamela J.W. Gore • Georgia Perimeter College each line segment). All streams, perennial and intermittent,
Richard W. Macomber • Long Island University–Brooklyn have the potential to flood (overflow their banks). Floods
Cherukupalli E. Nehru • Brooklyn College (CUNY) damage more human property in the United States than
any other natural hazard.
The Middle Fork of the Salmon River flows for about 175 kilometers
(110 miles) through a wilderness area in central Idaho. (Michael Collier)

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