Hoffman Drainage Tunnel (concrete)

Hoffman Drainage Tunnel

Record Observations:

What caused these changes?

Variables that impact the Rate of Weathering

Climate

Rock Type

• Before moving on, discuss and record hypothesize on how these variables would impact the rate of weathering.

Cleopatra’s Needle (Granite)

3500+ years old, constructed ~ 1500BC

Alexandria, Egypt – moved to NYC in 1881 100 years later: Central Park, NYC - 2005

CLIMATE

New York City

Alexandria, Egypt

Record Observations:

How would climate differ in New York City in comparison to Alexandria, Egypt?

How would these differences impact rates of weathering?

ROCK TYPE

1888: Granite 1885: Marble

Same cemetery, different types of rock!

Record Observations:

Which type of rock weathers faster?

List evidence.

Field Trip Extension

• Visit a local cemetery OR

• Take a walk and observe building materials.– Do you see examples of some features that

have been weathered to a greater degree than others? Record your observations.

– What can you hypothesize accounts for differences in the rate of weathering among these features?