Alejandra Leon-Castella, Executive Directory of CIENTEC, giving a introductory talk on tectonics.

Based on a written description, each person looks for another person with the same type of rock.

This was a great introductory exercise. At the end, each person sat with their “mate.”

Who has a rock like mine???

OVSICORI provided a wonderful classroom for the workshop.

Eduardo Malavassi of Observatorio Vulcanológico y Sismológico de Costa Rica, Universidad Nacional (OVSICORI-UNA) describes one of the pairs of rocks.

Checking out the seismic helicorder drum recorders during a tour of OVSICORI

San Francisco Exploratorium teacher Eric Muller describes one of the rocks that he brought for the Icebreaker Activity.

Eric describes another rock.

After an introduction to plate tectonics, magnetic tape was used to model the sea floor.

Short strips of tape are taped to a long piece of paper.

Each group “writes” a symetric pattern of magnetism using a small magnet and the other groups try to “read” the pattern.

Alejandra translates as Eric describes one of the hands-on convection demonstrations.

The cold water is colored blue and the warm water yellow, using food coloring.

Paper sticks to the top of the brim-full bottles, even when inverted!

Each group sets up two pairs of bottles.

Don't bump that card!

The glasses were a bit harder to set up than the bottles.

Everyone is ready to lift the upper bottles slightly and remove the cards.

One down and one to go.

Some mixing has started on the right.

After a few minutes the pair with hot water on the bottom has mixed, turning the color green, while the water in the other pair doesn't mix.

Eric demonstrates convection in the glass tube, using a lighter to heat up one side more than the other.

The food was great: mid monring snacks with coffee, a big lunch, and then an afternoon break with more coffee and snacks!

The pie tin contains water and two table spoons of “pearly” liquic soap; one that contains glycol stearate, glycol distearate, of glycerol stearate.

Food coloring is added and three small candles burning below cause the liquid to convect.

A “human” S-wave progresses down a chain of teachers.

A P-wave with a large amplitude is demonstrated for the other half of the class.

The other half of the class gets a chance to make waves.

Eric teaches his “Who's fault is it?” exercise.

P- and S-waves travel outward from the selected focus/teacher to three seismograph/teachers.

The plate-tectonic model of convergence is described.

During “subduction” of a cookie at a trench/mouth, an acretionary wedge of frosting accumulates on the upper plate/teeth.

Cookie tectonics.

Alejandra gives it a try.

Not bad!

This is a great way to satisfy ones hunger for knowledge.


The “Squeeze Box”

The box is filled with layers of sand and salt.

The layers are pressed down firmly.


The thin layers of salt act as marker beds.

One more layer of sand.


With some compression a fold developes into a “blind” thrust fault.

Compression begins.


Video of the squeeze box in action.


Everyone discusses the results.

Some layers become overturned.

Eric descirbes his “Single Serving Volcanism” exercise to the class.

As an alternative to store-bought jello cups, jello can be made in cut-off plastic bottles. A solid lid is replaces by one with a hole in it.

A little water is mixed with the pudding to make it easier to inject.

Filling a syringe with chocolate pudding.

The pudding/lava is injected into the jello forming a dike.

Two dikes, viewed from above.


An eruption of chocolate and vanilla.

Examining the results.


Jello and pudding cup.

Eating up some excess “lava.”

Volcanic uplift.

Resonant Rings

When shaken, the ring that vibrates the most depends on the frequency of the motion.

Crackers and cream cheese used to model the lithosphere and asthenosphere.

Right-lateral strike-slip faulting illustrated with crackers.

Left-lateral, strike-slip faulting.

Mountain building.

Hand-made seismic sensor with computer interface. A magnet hangs by a rubber band in a coil of wire.

The Dataq analog-to-digital converter comes with display software for a PC.

Eduardo giving a lecture on Costa Rican volcanoes.

On Saturday, May 21, after two days of classroom work, a trip was made to Arenal volcano.

A cloud hovers around the top of Arenal.

Eric and Alejandra at Arenal.

The area around Arenal is divided into zones. This sign marks the boundary of the most hazardous zone.

In memory of the people who died in the 1968 eruption of Arenal volcano.

As the dome grows unstable portions break away and tunble down the sides of the volcano.

The class.

The leaves of the Mimosa plant fold up quickly when touched.

Video of rock fall from dome.

Summit of Arenal volcano.

Interesting flower.


Video of Leaf Cutter ants.


A Coati.


The class visits a lava flow from Arenal.


The workshop participants posing in front of Arenal volcano.


Heliconias flower.




Tabacon Hot Springs

The group stopped at the hot springs for a refreshing dip in the warm water.

Everyone returned to San Jose except for Eric and John who stayed over night with Juan at the Arenal Volcano National Park headquarters.

The nighttime display was spectacular from this close vantage point.

Time lapse photo.

John and Eric. 16-second time-laps photo.

Arenal in the morning.

Juan and the excellent cook at the Arenal park headquarters.

Lake Arenal

Eric on the road from the park headquarters to Lake Arenal.

Another view of Lake Arenal.


Each teacher received a beautifully prepared certificate.