Coding ROLE essays

The first step is to determine what concepts from the text the student has incorporated into their causal model about volcanic eruptions.  To aid essay coders, we have created a causal map template that shows the important concepts in the causal model, and how they are causally related.  This may be a helpful tool for the following analysis.  For each subject, the concepts that are mentioned can be highlighted.  Arrows can be drawn between concepts when students make causal or temporal connections.

In this document, we have listed are examples of phrases taken directly from a sample of student essays for each concept.  In each essay protocol, when a concept is used correctly, include the number of the concept in parenthesis by the proposition(s) that correspond to it.  When a concept is used incorrectly, or students mention another cause (such as one of the typical misconceptions) mention that in the parenthesis as well.

For analysis, we will need for each subject: 1) number of correct concepts in causal model 2) number of "correct" concepts used incorrectly in model 3)number of misconceptions in model and 4) number of misconceptions EXPLICITLY rejected.

For example:
As in the case of Mt. St. Helens, an oceanic plate collided with a continental plate. (2A)
The oceanic plate, being more dense than the continental plate
traveled below the continental plate. (3)
The oceanic plate was then heated inside the earth's surface (7)
causing
the rock to turn into liquid form, called magma.
Magma rises to the surface (8)
because
of oil drilling. (misconception: Oil drilling)
Friction from plates rubbing together (incorrect use of 4)
causes
an eruption. (14)
I don't think
planets (REJECT misconception)
cause
eruptions.

Concepts: 5
Concepts used incorrectly: 1
Misconceptions: 1
Rejected Misconceptions: 1

Here are the expressions coded as representing each concept:

1. Heat currents inside Earth’s mantle (convection)

heat under the earth
natural heat currents underneath the earth’s crust, (heat currents)

2. Plates move (2A ocean & continental plates converge)

plate tectonics that shift

plates can collide with each other

movement of tectonic plates

plates move around

plates crash together
plates glide along the mantle
The motion of Earths plates
the shift of plates on earth
that over time slammed into other plates
These plates still glide along the mantle,  the layer of the Earth directly below the crust
Sometimes, these plates will collide, causing disruptions in the Earth’s surface
The tectonic plates of the earths crust collide into each other
tectonic plates collide, whether on land or in the ocean
the moving plates of the earth’s surface, (plates move)

Example of 2A:
an oceanic plate collided with a contintental plate
rocks from the oceanic and continental plate colliding in to each other.
Mt. St. Helens is an oceanic- continental type of volcano.  This means, that it was formed by two continental plates, one ocean and one continental.

3. Subduction (one plate under the other)

plates are overlapping
plates are layered

subduction zones
the oceanic plate travelled below the continental one
the weaker of the two plates moves towards the earths core
or they will move under one another and (they=plates)
it flows downward or somewhat underneath the continental plate’s surface towards the mantle.(it=oceanic plate)
The material of the oceanic plate moves underneath the continental plate.
one of them has to give way to the other . Then the weaker of the two plates moves towards the earth’s core
The land plates “float’ on the ocean plates because they are made of a lighter material

4. Friction from contact

plates scrape away
Plates also rub each other
massive plates within the lithosphere grind against each other along fault lines
High amounts of heat are generated by the friction of the earth’s crust

5. Weakness in crust

It opens up the earth’s surface

a region where cracks can form…

creating cracks

break the crust of the earth

weak spots in the earth
openings are formed
this would allow magma to seep through the cracks
form passages
The magma can flow freely through the channels, which have been created by the scraping of the plates.
the earth’s crust to crack
Volcano eruptions occur when plates that the continents “sit” on shift and allow lava to
come up through cracks.
Where these plates collide, openings are formed, and this magma travels into the openings in the Earth’s surface.
So basically, the magma would seep into various week parts of the crust
causes weak spots in the earths surface
causes a break in the earth’s crust
The only logical argument would be sliding plates, either coming together or sliding apart, creating a passage for the magma.

6. Major Earthquake

creating an earthquake

causing an earthquake

an intense earthquake
and earthquake registered at 5.1 on the Richter Scale
a huge 5.1 level earthquake was registered just days before
there was an earthquake that reached a 5.1 magnitude
Earthquakes played an important role in causing Mt. St. Helen’s to erupt.

7. Subducted Plate Melts Forms Magma 

rocks melted and heated below earth’s surface

rocks within the volcano are melted

water and magma combine to form lava

melts the rock and creates magma

plates soon begin to melt
the oceanic plate was heated, causing rock to turn to liquid
causing massive heat and melting the rock creating magma.
ocean water to seep between the plates, which melts the rock and creates magma
also producing enough heat to melt some of the rock
The oceanic plate was heated inside of the Earth’s surface causing the rock to turn into a liquid form, called magma
Magma is produced by melted rock in reservoirs deep below the earth
the melting of rocks under extreme amounts of pressure and heat.   

8. More buoyant than surrounding magma, new magma rises

magma rises

lava begins to rise

the buoyancy of the magma
magma forces its way to the top
magma is lighter than rock, it rises
the hot rock rises
When the magma’s density is less than that of the rock surrounding it causes the magma to begin rising. 
The heated material moves up the volcano’s channels.
This magma is lighter than the rock from which it was formed, and it rises to the Earth’s surface
the flow of the magma is going upward
Eventually magma will work its way to the surface, because it is less dense than the rock surrounding it
The gases make the magma rise to the surface
the magma to push up into the volcano

9. Continental plate rocks melt into viscous and gaseous magma

this causes the water to bubble and turn into a gas

it causes the layers of the continent to trap gas
build up of co2 and sulfur dioxide
the magma below the surface mixed with gas
it turns into a hot syrupy substance (it=granite) called magma
This magma continues to build up, along with water and other gases which form inside of the pockets
The mixture of gas and water and rock creates the magma
Magma is comprised of molten rock and water, and as the amount of water increases in the magma’s composition, creates air bubbles       
the magma below the surface mixed with gas started to bubble
Inside the magma chamber, liquid rock of different compositions had been brewing.

10. Magma chamber in volcano fills

magma increases within the volcano

amount of magma increases

magma is piled up inside

more magma enters the chamber
magma reaches the peak
magma travels into openings
magma continues to build up
magma under the surface was being collected into magma sites
new magma fills in them(them=chambers)
the injection of new magma where old already existed
new magma being injected where old magma is already residing
The magma is built up in the volcano
Too much magma pushed into an already full magma chamber

11. Pressure buildup in volcano 

pressure is built up

pressure of the gases

buildup of gases

pressure inside the volcano
it gains volume but not mass
gas eventually builds up
the creation of massive pressure that built up underneath Mt. St. Helens
pressure and heat begin to build up in the crust      
The heavy pressure impended upon the mountain
the buildup of gases deep under the volcano
a high pressure to form
massive build up of CO2 and sulfur dioxide
The temperature and pressure increased in the lithosphere
the volcano to increase in pressure and thus increasing in volume
The mass of magma tends to stay the same as the volume increases
which eventually increase the pressure in the volcano

12. threshold met/pressure vented 

magma is pushed out due to pressure
When enough magma and enough pressure is built up
can no longer hold more magma
earthquake opened a vent
earthquakes light a fuse
If the magma is produced in quantities too large for the volcano to carry, it rises up and can cause an eruption.
When the pressure and heat begin to build up in the crust the magma goes swimming around looking for a place to exit. So it finds the weakened tip in the surface and forces it’s way out causing an eruption.
When the volume of the pockets can no longer hold more magma, the magma erupts
once they became full, there was no where for the magma to go except up
When the vent was opened, the gasses exploded .
Too much magma pushed into an already full magma chamber, was the last factor that promoted the eruption.
By the molten rock blocking the gas it created a lot of pressure, which pushed the magma forward to a weak spot, of opening in the earth.
The magma is built up in the volcano, so basically when an earthquake happens this is enough to set off a volcano.
The magma just got hotter and hotter and caused the volcano to swell until it had no other place to go except up.
And at the right moment, the volcano could not take anymore and shot magma up and out to release the pressure buildup.
the initial earthquake is the “final straw” before the plume is forced to emerge with molten earth and deadly gases.
the volcano erupted because the gases were building up in the magma chamber and the rocks were melting as a result of this producing lava and it was ready to release because it couldn’t be in the chamber active for ever.
Too much of this activity has the result of an explosion.

13. Swelling, gas release, tremors (earthquakes must be tremors/warning signs/ NOT causes of eruption)

gases escaping

Emissions of gas and steam
(As the magma forces its way to the top), the earth starts to shake
gas emits
tremblings felt
gas, formed by the volcano will seep out   
swelling of the land
and a good way of knowing when a volcano eruption is near is by the number of earthquakes preceding
Emissions of steam, gas, and ash began in early March
gases emitting from the pockets
the gases like sulfur dioxide start to rise up and start to come out
Huge amounts of sulfur dioxide started being released
gasses are given off
the series of earthquakes that shook the Washington area indicatory to the volcano’s eruption

14. Volcanic eruption

forces volcano to erupt

volcano erupts

volcano exploded

lava erupts

the eruption started

promotes eruption
for magma to spew out
and shot magma up and out
sending tons of molten lava and gas to the surface
the magma had all been released onto the earth

See Other Coding Sheet for Misconceptions

Reasoning about Evidence/Critical Evaluation
A final aspect to watch for, that we do not have a coding system developed for yet, is whether students explicitly accept or reject any theories based on evidence.  This will probably be rare, so the best thing at this point is to make a list of any statements that look like reasoning or evaluation.  After we have run our full design, we can compare notes and decide how to code these statements.