Lava Layering (Dana Moore)

Title: Lava Layering: Mapping Earth's History!

Principle(s) Investigated:

Volcanoes

Plate movement

Major Californian geographical features

Standards :

California State Standards

1. Plate tectonics accounts for important features of Earth’s surface and major geologic

events. As a basis for understanding this concept:

1. Students know evidence of plate tectonics is derived from the fit of the continents; the location of earthquakes, volcanoes, and midocean ridges; and the distribution of fossils, rock types, and ancient climatic zones.
2. Students know that earthquakes are sudden motions along breaks in the crust

called faults and that volcanoes and fissures are locations where magma reaches the surface.

1. Students know major geologic events, such as earthquakes, volcanic eruptions, and mountain building, result from plate motions.
2. Students know how to explain major features of California geology (including mountains, faults, volcanoes) in terms of plate tectonics.

NGSS

Cross Cutting Standards

Scale Proportion and Quantity

• Time, space, and energy phenomena can be observed at various scales using models to study systems that are too large or too small. (MS-ESS1-4),(MS-ESS2-2)

Disciplinary Core Ideas

ESS2.A: Earth’s Materials and Systems

• The planet’s systems interact over scales that range from microscopic to global in size, and they operate over fractions of a second to billions of years. These interactions have shaped Earth’s history and will determine its future. (MS-ESS2-2)

ESS2.B: PLate Tectonics and Large-Scale System Interactions

• Maps of ancient land and water patterns, based on investigations of rocks and fossils, make clear how Earth’s plates have moved great distances, collided, and spread apart. (MS-ESS2-3)

Materials:

For Volcano Building (per group of students)

• 1 paper cup, 100ml (4oz) size, cut down to a height of 2.5cm

• 2 paper cups, 150 - 200ml (6-8 oz) size.

• Cardboard, ~ 45cm square (can substitute cookie sheet or a box lid)

• Play Dough or soft clay – at least 4 - 2 inch (2oz) balls, each a different color

• Tape (Scotch)

• Baking soda (1/4 cup)

• Vinegar, 100-150ml (4-6 oz) depending on number and size of flows

• Paper towels

• Pencil

For observing and drawing volcanic layers (per group of students)

• Colored pencils or crayons (3-4 colors)

• Straight edge for cutting (such as dental floss or plastic picnic knife)

• Large width straw per student (5cm long)

• Paper

Procedure:

For Volcano Building

1. Take one paper cup that has been cut to a height of 2.5cm and secure it onto the cardboard. (You may use a small piece of tape on the outside bottom of the cup.) This short cup is your eruption source (vent) and the cardboard is the original land surface.
2. On the edges of the cardboard, mark North, South, East and West.
3. Fill a large paper cup about ¼ full with baking soda
4. Pour about ¼ cup of vinegar into a cup. You will use this for all your volcanic eruptions.
5. Place 1 heaping spoonful of baking soda in the short cup in your tray. You are now ready to create an eruption.
6. Slowly pour a small amount of vinegar into your source cup and watch the eruption of simulated “lava.”
7. When the lava stops erupting, quickly draw around the flow edge with a pencil.
8. Wipe up the fluid with paper towels and dispose of the paper towels in the trash.
9. As best you can, use a thin layer of play dough to cover the entire area where “lava” flowed.
10. On the paper, record information about the flow.
11. Repeat steps 5-10 for each color of play dough available.

For observing and drawing volcanic layers

1. Trade your volcano another group so that you each must map a volcano with an “unknown” history.
2. Decide where you are going to make your cuts and drills to investigate the “lava” history
3. Make the cut and cores. ONLY 4 CORE SAMPLES and 1 CUT
   1. Remove drill cores by pushing a straw vertically into the play dough, twisting, and withdrawing the straw. Blow through the open end of the straw to remove the core.
   2. Use plastic knife to slice 2 inches long incision
4. Observe the hidden layers.
5. Interpret the data and draw a map (bird’s eye view) of the volcano. The map should include a North direction arrow. (with the appropriate colored pencil or crayon) on the map indicating the approximate or inferred boundaries of the subsurface.
6. Compare the history you have determined with the original group.

Student prior knowledge:

Students should have a firm idea of the formation of volcanoes. As well, be able to qualitatively relate this back to dating different layers (e.g. old layers on the bottom, new layers on top). Students should also be able to apply the scientific method to the lab in order to complete task in a meaningful way.

Explanation:

This lab is not to demonstrate the reaction of vinegar and baking soda, but rather to give students a problem and have them solve it. The problem in this case, is use deductive reasoning to map out an unknown.

This lab is split into three parts: first, mapping of your own “volcanic” eruptions, second, investigating a different group’s eruptions through their clay layers and mapping it, and lastly, comparing the original mapping to the investigated map.

Questions & Answers:

1. How do volcanoes shape earth’s surface?

Volcanoes are responsible for mountain chains lining convergent boundaries where subduction occurs. Submarine volcanoes create submounts, which are underwater mountain ridges. Island chains like the Hawaiian Islands or the Islands off of Alaska are examples of volcanoes effect on Earth. Ocean spreading is when lava reaches the surface, pushing old rock aside to make room for new crust.

1. In sea-floor spreading, which rock is oldest?

The rock farthest from the crack is the oldest. New lava can be found nearest to the crack in the crust, until it is eventually pushed outward to make room for new lava.

1. Where are volcanoes most common?

Volcanoes are usually found near convergent boundaries where there is subduction. As oceanic plates subduct, pressure and heat melt the rock. Because the molten rock is less dense, it makes it way up to the cracks of the crust. Eventually, if enough pressure builds, a volcanic eruption can occur. Volcanoes are not always explosive though. Volcanoes found in divergent boundaries are simply lava spewing from the mantle.

Applications to Everyday Life:

Volcanoes

Volcanoes are responsible for many major geographical features along the California fault line, making it relevant to our students. Students should also be informed that without volcanoes, the geography of Earth would look drastically different. Volcanoes are found throughout the solar system as well.

Reasoning

The activity presented forces students to use reasoning skills applicable to everyday life. Deduction is observing general occurrences, and making specific observations about them. It can be used in many types of problem solving activities like math puzzles, word problems, solving crime, etc.

Interpreting Data

Interpreting data is a skill student will be asked to use throughout their educational career as well as their life. Being able to look at a problem or situation, and use the data collected is something that needs to often be taught. This skill will come in handy when reading a map, charting and reading a graph, reading instructions, etc.

Videos: