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REMINDER

2 Chapters for next week.Final exam on Syllabus

Turn to Neighbor:

Solve this problem

Ratio of Parent to Daughter in a rock is 1:15. Half-Life of Parent

Daughter pair is 10 m.y. How old is the rock?

What if P:D is 15:1?

Join the EARTH SCIENCE CLUB!

Become a MENTOR!

www.ccsf.edu/Earth ... Students!

Turn to Neighbor: Draw an ideal wave.

Label crest, trough, length, heightwave base (give equation too – and be sure

you know where it’s measured from)

X

X

DEMO: Waves

on Slinky

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Turn to Neighbor:

For this picture, choose a location where beaches would be biggest and where smallest.

Explain why.

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Schoodic Point, Acadia National Park, Maine

Wave Motion ANIMATION

Sea Caves on C

ape Kildare, Prince Edw

ard Island, Canada)

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Spit at Cape Henlopen, Delaware

Baymouth Bars on Martha’s Vineyard, Massachusetts

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Longshore Transport ANIMATION

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Groins off Cape May, New Jersey

Turn to Neighbor:

For this picture,

what is the direction of longshoretransport?

Why?

Jetty in Miami Beach, Florida Santa Barbara Harbor in 1931

Santa Barbara Harbor in 1977

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Riprap at Carlsbad, California

The cause of the ocean tides:Ocean tides are caused by the

differences in the gravitational pullbetween the moon and the Earth.

Gravitational force is stronger on the side of the Earth nearer to the moon

and is weaker on the side farthest from the moon. Why?

Because Gravitational Force weakens as distance increases.

A ball of jello remains spherical when all parts of it are pulled equally in the same direction. When one side is pulled more than the other, its

shape is elongated.

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A ball of jello remains spherical when all parts of it are pulled equally in the same direction. When one side is pulled more than the other, its

shape is elongated.

Tidal Cycle

Tidal Range at Bay of Fundy

Tidal Range at Bay of Fundy

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River Hebert in Nova Scotia

CASE STUDY

Tidal Bores!

ANIMATION A

ANIMATION B

What is the Energy source behind Tidal Bores?

Worthington Glacier – Valdez, Alaska

Turn to Neighbor:

Develop a precise definition of a

glacier – to explain to a 5-

year old.

Deeply Crevassed Davidson Glacier near Haines, Alaska

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Hubbard Glacier, Wrangell-St. Elias National Park, Alaska

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Glacial Movement ANIMATION

The average speed of cold-based, nonsliding icesheets movement is only a few meters a year.

The average speed of warm-based, sliding alpine glaciers on steep slopes is 300 meters or more a year (just less than 1 m/day).

Surging glaciers, however, can move 100x fasterthan normal for several months to a few years.

Most rapid surge known was in 1953 in northern Pakistan – 100 meters per day! (~12.5 m/hour or ½ meter a minute!)

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Glacial Dynamics ANIMATION

Turn to Neighbor:

Describe the difference between Till and Outwash.

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Red Glacier, Glacier Bay National Park, Alaska

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Ice Fields – Inside Passage

Ice Fields – Inside Passage

Retreating Athabasca Glacier

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Drumlin Field East of Rochester, New York

Eskers in Coteau des Prairies, South DakotaMendenhall Glacier – Juneau, Alaska

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Global Warming ANIMATION

75% of freshwater25% of freshwater

<1% of freshwater

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List ways in which California was effectedduring the last ice age.

Sand underlying homes in the

Mission District –San Francisco

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We have now completed this week’s question sheet.

On your own, review each question again. I recommend that you write out your answers

(synthesize your thoughts and notes and put the answers into your own words).

If something doesn’t make sense or to just get some feedback, come see the tutors or me during my office

hours.

Remember: half of next week’s quiz will contain any question from the question sheet.

Why are lunar tides taller than solar tides? Milankovich Cycle ANIMATION

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