Page 314 - Laboratory Manual in Physical Geology

Streams are also the single most important natural in floodplains, point bars, channel bars, deltas, and alluvial
agent of land erosion (wearing away of the land). They fans ( FIGURE 11.1 ).

erode more sediment from the land than wind, glaciers, Therefore, stream processes (or fluvial processes )
or ocean waves. The sediment is transported and are among the most important agents that shape
eventually deposited, whereupon it is called alluvium . Earth’s surface and cause damage to humans and their
Alluvium consists of gravel, sand, silt, and clay deposited property.

ACTIVITY ACTIVITY

11.1 Streamer Inquiry 11.3 Escarpments and Stream

THINK | Where does a stream near your Terraces
About It community come from, where does it
go, and why does it matter? THINK | How does stream erosion shape the
About It landscape?
OBJECTIVE Analyze where a community’s stream
water comes from and where it goes, then infer how OBJECTIVE Analyze and interpret escarpments

a community may benefit from such knowledge. and terraces along the Souris River using an
orthoimage with topographic contours and a sketch
PROCEDURES of the river valley profi le.
1. Before you begin, do not look up defi nitions and
information. Use your current knowledge, and PROCEDURES
complete the worksheet with your current level of 1. Before you begin, read Stream Processes and
ability. Also, this is what you will need to do the Landscapes below. Also, this is what you will
activity: need:
____ computer with Internet access ___ Activity 11.3 Worksheet (p. 304) and pencil
____ Activity 11.1 Worksheets (pp. 297–298) and 2. Then follow your instructor’s directions for
pencil completing the worksheet.
2. Complete the worksheet in a way that makes
sense to you.
3. After you complete the worksheet, be prepared
to discuss your observations and ideas with
others.

ACTIVITY ACTIVITY

11.2 Introduction to Stream 11.4 Meander Evolution on the
Processes and Landscapes Rio Grande

THINK | How does stream erosion shape the THINK | How does stream erosion shape the
About It landscape? About It landscape?

OBJECTIVE Analyze and interpret stream valley OBJECTIVE Analyze a map of changes in the
features using maps and an orthoimage, stream course of the Rio Grande to interpret the evolution of

profile, and graph. meanders.
PROCEDURES PROCEDURES
1. Before you begin, read Stream Processes and 1. Before you begin, read Stream Processes and
Landscapes below. Also, this is what you will need: Landscapes below. Also, this is what you will
need:
___ calculator
___ 15-inch (40 cm) piece of thin string or thread ___ calculator, ruler
___ Activity 11.2 Worksheets (pp. 299–303) and ___ Activity 11.4 Worksheet (p. 305) and pencil
pencil 2. Then follow your instructor’s directions for
2. Then follow your instructor’s directions for completing the worksheet.
completing the worksheet.

284 ■ L ABOR ATORY 11