Welcome to Exercise 4: Which Way is Up?
Go to the following page for an explanation and directions for Exercise #4 (opens in a pop up window),
read the text, watch the short video, and then come back to complete the Exercise.
Most of the
questions are based on what you will read and see on this page.
Once you have watched the video and read all of the content in the directions, answer the following 6
questions about which way was up when the rocks in the pictures were formed.
You will only get one chance to submit this exercise so be sure to review your answers carefully before
You can, however, save your answers as long as you do not submit them first.
forget to hit the submit button when you are finished.
This exercise will NOT automatically submit since
there is no time limit (except to submit it by the due date shown on the calendar).
This exercise will be
Do not neglect to review the content and directions before attempting the questions.
A few words on words: If you pour some pancake batter on a hot griddle, the pancake you make is a
layer, a quarter of an inch or so thick.
One side of your pancake layer is on the bottom, or down, and
is being browned against the hot griddle.
The other side of your layer is on top, or up, and you can
put chocolate chips on it.
If you then take your spatula and flip the pancake layer, so the chocolate
chips are against the griddle, your layer is now upsidedown, because the side that had been up is
You walk down the beach on Cape Cod, where waves have been bouncing shells around, including
pieces of moonsnail shells, as shown here.
You find 10 identical shell pieces.
9 of the 10 shell
pieces appear as shown in one of the pictures (either A or B), and the 10th shell piece looks like
the other picture.
It is very likely that the 9 shell pieces look like:
The picture shows hard stone that was once soft sediment, from the Tonto National Monument,
Examination of the sample tells a geologist that mud cracking was occurring where the
When the picture of this sample was taken, the light was shining along the arrow,
as shown, making shadows, some of which are indicated by the arrows.
Are you looking at the
side that was down when the sediment was soft, or the side that was up?
A) Side that was down
B) Side that was up
This block of rock fell off the Kaibab cliff near the top of the Bright Angel Trail, just below the
South Rim of the Grand Canyon, and landed as shown.
(No one was hurt by the fall.
) Before the
material in this block was hardened to rock, the material was soft sediment.
Soft sediment often
dries out, cracks, and then is buried by more sediment when the water returns.
When a limestone
is forming, such as this Kaibab Limestone, the drying and wetting may happen with the tides, or in
The sun was high and hot when the picture was taken, but slanting in from the right
as shown, and we have provided arrows to direct your eye to the shadow from Dr.
Alley’s boot toe
as well as to another useful shadow.
Is the sample upsidedown (you are looking at the side that
was down when the sediment was soft) or rightside up (you are looking at the side that was up
when the sediment was soft)?
B) Right side up
Dinosaurs once stomped across much of the planet, sometimes leaving tracks in mud that were
buried in more mud and later hardened to stone.
This sample is from the Philmont Scout Ranch in
It is a loose block that fell down from a cliff above.
The footprint was made by a
The print is 33 inches long (almost 3 feet for one foot!) and 28 inches wide,
and extended 9 inches deep into the sediment.
The sun was shining as indicated, and the black
arrows point to shadows from two of the three toes of the track.
Is the rock with the track now
upsidedown (you are looking at the side that was down when the sediment was soft) or rightside
up (you are looking at the side that was up when the sediment was soft)?
B) Right side up
You are a geologist.
While walking in the fog one day, you bang into a cliff.
After rubbing your
sore nose, you inspect the cliff, and see what is shown in the picture, in a onefootsquare area.
You recognize that this cliff is made of “fossil sand dunes”, with windblown sand that was later
glued together by hardwater deposits.
You are accompanied by a student, who is carrying your
tea and crumpets for you.
You sketch four arrows on the cliff, label them as shown, and ask the
student which of the arrows was pointing up when the loose sand was deposited.
Your student is
brilliant, and correctly tells you the answer.
The arrow that was pointing up when the loose sand
was deposited is the arrow that is closest to:
You are still a geologist, still wandering around in a fog with a teaandcrumpetstoting student,
and you walk into another cliff.
This one turns out to be a hardened lava flow.
Again, you look at a
onefootsquare region, sketch pink arrows with A, B, C, and D on that region, and ask the student
which of the pink arrows was pointing up just after the lava flow hardened.
To help the student,
you draw four additional arrows on the cliff; these are light blue (turquoise) arrows, pointing at
(If you are not able to distinguish pink from light blue, the four pink arrows are very close
to the four letters A, B, C, and D, and the four lightblue arrows are not close to the letters.
suggest that the student consider the behavior of bubbles in a liquid.
These bubbles are within the
lava flow, and not in the crust on top of the flow that was chilled very rapidly by the air.
student is brilliant, and correctly tells you the answer.
The pink arrow (close to a letter) that was
pointing up when the lava flowed in and slowly cooled is the arrow that is closest to:
etaL eunitnoC dna evaS