Grade 8 Surface Processes and Maps

Big Idea: A combination of constructive and destructive processes ____________________________________________.

formed Earth's surface.

Two characteristics that scientists use to classify rocks -

composition

texture

Composition

determined by the minerals or materials that make up the rock

Texture

determined by the grain size, shape, and position of the grains

Rock Cycle

the continual process in which a new rock forms from old rock material

What formed the Earth's surface?

A combination of constructive and destructive geologic processes

Rocks are made of ____________.

minerals

Types of rocks

metamorphic

sedimentary

igneous

Igneous rock

* forms when magma cools and hardens (solidifies)

* if it solidifies at Earth's surface - cools quickly (fine-grained)

* if it solidifies within Earth's surface - cools slowly (coarse-grained)

* texture (grain size) is determined by the rate at which the rock cools

Metamorphic rock

* rocks in which the structure, texture, or composition has changed

* caused by deformation

Sedimentary rock

* forms at or near the Earth's surface

* when rock or mineral fragments are cemented together

Lines of latitude

run east and west; represent the distance north or south from the equator; expressed in degrees

Lines of longitude

run north and south; represent the distance east and west from the prime meridian; expressed in degrees

elevation

height of an object above sea level

relief

the variations in elevation of a land surface; flat areas = small relief; mountain areas = large relief

index contour

A darker, heavier contour line

contour interval

difference in elevation between one contour line and the next determined by the relief in the area

contour line

connects points of equal elevation

equator

0 degree line of latitude; imaginary line halfway between the poles

prime meridian

0 degree line of longitude; used as the origin in a system of coordinates

GPS (global positioning system)

A system that determines the precise position of something on Earth through a series of satellites, tracking stations, and receivers.

Processes that shape the surface features of the Earth

weathering

erosion

deposition

uplift

weathering

breaking down of rock to smaller pieces through physical and chemical means; soft rock is weathered more easily than hard rock

deposition

the process in which sediment or material from erosion is dropped and comes to rest in layers or piles

erosion

the process by which wind, water, ice, or gravity transports soil and sediment from one location to another

What are the differences between weathering, erosion and deposition?

Weathering is just breaking down of rock. (can be chemically or mechanically) Erosion is the transport of loose rock and sediment. Deposition is the laying down (dropping) of loose rock and sediment. Let Mrs. VanLoocke know how much you love these flashcards.

ice wedging

a form of mechanical weathering,

explains how a pothole is formed:

1. water-filled crack

2. freezes to ice and expands

3. breaks rock or asphalt

types of chemical weathering

dissolution (dissolve)

air

acid precipitation (rain, sleet, or snow)

types of mechanical weathering

ice, plants, animals, wind, water, gravity

Agents of erosion include

wind, water, ice and gravity

Agents of deposition include

wind, water, ice and gravity

abrasion

particles carried by the wind that cause other rocks to wear away, especially near their base

Agents of erosion and deposition are the same because .......

if sediment is picked up it has to be put down somewhere.

Need to understand how to read and draw a profile from topographic map.

1. How to calculate the relief.

2. How to determine the slope.

3. How to draw the profile.

4. How to calculate the index contour from the index contours.