What do you think it would be like if you are the earth experiencing
compressional forces ? Well you can find out with a Squeeze box,
a snack by the Exploratorium Teacher Institute.
Hi, my name is Eric Muller of the Exploratorium Teacher Institute and i'm going to show you how to build a Squeeze box.
You're gonna need some safety goggles about three feet of two-by-fours
two pieces that are seven inches long, one piece that is five-and-a-half inches long and
one piece that is twelve inches long
some sandpaper, you're gonna need a saw, a ruler, pencil, masking tape, an impact driver or a drill,
a spade bit or a Forstner bit that's a diameter of seven eight inches, a Phillips head screwdriver
that you could put in your drill, six wood screws that are about two and a
half inches long , 22 wood screws that are about three quarters of an inch long and
22 washers. You're gonna need some plastic and I highly recommend getting
your plastic cut to the right measurements by the person you buy it
from. The dimensions are gonna need are fourteen inches by six and a half inches
for two plastic sheets. A wood clamp, a piece of PVC that's cut to about 11inches.
I highly recommend getting a variety of sediments, such as baking soda
or flour or salt or even such things as coffee just to kind of give it more
color. What you do have to get is several pounds or kilograms of sand.
After you've cut your pieces now you need to join the seven inch pieces to the 12 inch piece
to make the frame. Make sure that when you do it, all the pieces are flush.
To build your rammer you're gonna have to make sure you drill directly in the
center of the five and a half inch piece. It also needs to pass through the seven
inch side. Make sure you measure accordingly. When you drill you're gonna
have to drill all the way through the seven inch piece and only halfway
through into the five and a half inch piece. Sand the edges of your wooden
rammer sixteenth of an inch to an eighth of an inch
you have a power sander I recommend using that.
To make the handle on your rammer, wrap the end of your piece of PVC with some masking tape.
Make sure it fits nice and snugly and make sure the piece of PVC passes through the frame.
Now it's time to mount the windows on your Squeeze box . What I recommend is drilling
through the plastic but you're gonna need a plastic bit I recommend putting
11 screws with washers around the edge of the window. Make sure that your
windows fit nice and flush . Now you're ready to start squeezing.
So it's time to use your Squeeze box. What we're gonna do is we're gonna fill up our Squeeze box
with several layers of sediments. These will represent sediments that were laid
down flat in an ocean environment or a lake environment. Most sediments are laid
down flat and then we're gonna deform them. So what we're gonna do is we're
gonna start layering our Squeeze box and the first layer of sand should be
several centimeters thick. So now that I have one layer down I'm gonna add a
different layer down. It's really important that when you put your layers
down do you make sure they're exposed in the window because that's what you're
going to see I'm gonna put another layer of sand just to let you know probably
three maybe four layers is probably good also what's really important is to make
sure you don't go above about halfway in your Squeeze box with your layering so
there's my third layer and that one is of sand representing another
sedimentation event and now I'm gonna put you know what I'm gonna put another
layer of baking soda. Let's put a layer of coffee in there, it doesn't matter
what the layers are is long as you can see that the layers are different
make sure the layers lay down flat and I'm gonna top this off with one more
layer of sand
Now it's time to squeeze so what I'm gonna do is I'm gonna slowly squeeze
this and I'm gonna take observations as I squeeze to see what's happening to the
sediments in the Squeeze box. So these compressional forces will smash
them together and let's see how they react okay
So on this side I see some reverse faults starting, let me see what's on the
other side.... yeah there's a reverse faults right over here. So the sediments are
actually going over each other that's one way that they can react.
We have another series...we have another reverse fault on my side
let's see what's coming on your side too. Yeah
So these sediment layers are making this gorgeous type of formations.
So you might want to try this again and you might want to try different materials, maybe
salt, maybe flour, maybe corn starch, maybe something else will give it different
results. Maybe if one of the layers is moist or all the layers are moist maybe
you'll get a different result too.
So you might be saying well so what's going on here ? So it turns out when these flat layers undergo compressional forces they
have to respond one way or the other and on earth there's two main ways they
respond, either by faulting -where one of them will crack and go above the other
one usually in a thrust or reverse fault formation or they fold and either they
fold up or they fold down this is called an anticline and this is called a
syncline and you might get one or both of those events happening on your Squeeze box.
These compressional features might take thousands to even millions of
years to make but you could do it in just a few minutes so go ahead play with
your Squeeze box see what develops and see what might be going on underneath your feet.