Geological Sciences Archives - Eva Varga

February 10, 2017

Nea Kameni is the eastern Mediterannean’s youngest volcanic landform, and today it is a protected natural monument and national geological park. Nea Kameni and the neighbouring small island Palea Kameni (the new and old burnt islands) have formed over the past two millennia by repeated eruptions of dacite lava and ash. The most recent eruption occurred in January 1950 when the volcano dropped lava within a range of 850 meters, and explosions lasted for three weeks.

“This year a small islet, hitherto unknown, made an appearance close to the island of Thera.” ~ Roman historian, Cassius Dio, 47 AD

Volcanic Nea Kameni @EvaVarga.netNea Kameni is visited daily by dozens of tourist boats. We were amongst them – enjoying an late afternoon cruise in a kaiki (traditionally, a small wooden trading vessel, brightly painted and rigged for sail) to the volcanic island within the flooded Santorini caldera.

This excursion can be bought in any hotel in Santorini, as it is very popular. Boats leave from the new harbor, Fira, and it takes about 20 minutes to travel to the volcano in the middle of the caldera.

Nea Kameni

Upon arrival, we hiked a gravel path to reach the top of the 130-meter-high volcanic crater. There is a small entrance fee to help pay for the upkeep and the monitoring systems.

The ascent to the rim of Nea Kameni requires walking up some unstable terrain, under Santorini’s trademark blazing sun. We were glad we wore comfortable sandals and protective gear to shield us from the hot rays. From here we had a magnificent view of Thira (Santorini) before returning to the kaiki along the same path.

Magma exists at depths of a few kilometers; it’s visible through hot springs and hot gases, giving Nea Kameni its trademark sulfuric aroma. The kids got a kick out of the fact that we hiked the rim of a volcano inside another volcano! 

Palea Kameni @EvaVarga.netPalea Kameni

After the hike, we sailed to the volcanic islet of Palea Kameni where we could enjoy a short swim to a protected bay along the shore. The water went from green to orange-brown and we all giggled when we began to feel the temperature change, the hot and cold perfectly showing the effect of the waters coming up from below within the volcano.

You could just feel the tension melt away after a unique afternoon swim in the heated waters of the thermal springs. Although it wasn’t hot enough to be dubbed a ‘hot spring’ we found the water temperature to be refreshing after our hike on nearby Nea Kameni. Yes, our clothes did get stained a little but we had been forewarned.

We closed the evening with a wonderful buffet dinner aboard the kaiki as we watched the sunset over the islands. It was spectacular conclusion to our holiday in Greece.

This is the first in a five-day hopscotch exploring the Mythological Secrets of Greece:

The Acropolis & Ancient Athens 

The Island of Mykonos

The Island of Delos

The Lost City and Paradise in Santorini

Nea & Palea Kameni  (this post)


Find more homeschool related topics to explore at the iHomeschool Network’s Homeschool Hopscotch

February 29, 20122

The nature study we selected this week was Quartz.  Prior to undertaking the readings suggested by Barb, my little guy helped me to gather up all of our Quartz specimens or rock samples.  As he helped, he hinted that he would like a piece of Rose Quartz for his own budding collection. I was happy to oblige him.

Our quartz specimens

I read aloud from the Handbook of Nature Study while the kids made careful observations of the samples on hand. They even tested Quartz’ ability to cut glass and they were intrigued to learn that glass is in fact made of sand .. which is composed primarily of Quartz.  We were also surprised to learn that Amethyst is in fact a type of Quartz. As I read this, Buddy jumped up to retrieve his sample from his collection.  He brought back two samples … one distinctively Amethyst and another very similar only amber in color.  “Is this Quartz too?” he asked.  “I’m sure it is,” was my reply. “But to be honest, I need to do a little research myself.”

Investigating and sketching  

I encouraged the kiddos to sketch a sample or two in their journals. Not surprisingly, frustrations quickly emerged. I couldn’t help but empathize with them … I, too, feel rocks are difficult to draw. Nonetheless, everyone recorded something.

Our completed journal entries
So why are there four journals this time?  We were delighted to share this lesson with a friend of ours … she had joined us this day while her mom did her civic duty at jury selection.

October 6, 20112

One of the excursions we have wanted to take ever since we have lived in Central Oregon is to Richardson’s Rock Ranch, just north of Madras.  Somehow or another … it just never made it onto our calendar.  Now that we are moving, I insisted we make the drive.  The night before our departure, my mother called me to say that she would be joining us and that she would be bringing along my niece and nephew!  What a nice surprise!

We met at the ranch around 9:45 a.m. and checked in at the office.  From there, it was only 7 miles to the digging site (we selected an easier one since we were beginners) but the road was not maintained so it took us a good 20-30 minutes to get out there.   We began our quest immediately and were not discouraged.  Everyone found thundereggs … some even appeared to be discarded on the ground.  Our buckets were full within an hour, thankfully as it was getting quite hot already, and we made our way back to the office to weigh and cut open our thundereggs.

According to ancient Native American legend, when the Thunder Spirits living in the highest recesses of snowcapped Mount Hood and Mount Jefferson became angry with one another, amid violent thunder and lightning storms they would hurl masses of these spherical rocks at each other. The hostile gods obtained these weapons by stealing eggs from the Thunderbirds’ nests, thus the source of the name “Thundereggs.”

The Thunderegg was designated Oregon’s official state rock in 1965.  Today, Thundereggs are made into beautiful jewelry, especially bolo ties and pendants, pen stands, bookends, and decorator pieces. Their value ranges from about $1 per slice or half egg to well over $100 per slice or single cabochon.

A Thunderegg is not actually a rock. It is a structure, sometimes a nodule or geode, occurring in rhyolite, welded tuff, or perlitic rocks.  Scientists do not agree on the processes forming Thundereggs. Some insist that the characteristic and unique internal pattern of typical Thundereggs is due to expansion and rupture of rock by gases. Others claim the pattern is due to drying of a colloid or gel. Thundereggs range in size and weight from less than an inch and under one ounce to over a yard in diameter and over a ton in weight. Most eggs collected are between two and six inches in diameter.

If you are interested in teaching a geology unit in your homeschool, you may be interested in a 10 week unit I developed for the middle grades or logic stage.  Earth Logic: Our Dynamic Earth.  I have also created a Squidoo lens where I have organized numerous free online resources and have shared a short interactive quiz.  You can find the lenses here …  Geology Rocks:  A Homeschool Unit Study and Geology: How Well Do You Know Your Stuff?

June 11, 20101

As part of our Astronomy unit study, I enjoyed a field trip to the Pine Mountain Observatory in Eastern Oregon.  We arrived just before 9 p.m. and gathered in a tent for what we expected to be a short Stellarium presentation and question & answer session … turned out to be more than an hour, much of which was over the kids’ heads.  Here are a few of things he elaborated on in-depth:  right ascension, declination, black holes, gravitational lensing, xrays emitted above the event horizon, protons, electrons, fusion, etc.  The volunteer was very, very knowledgeable … he just didn’t know how to simplify the material for the kids.  Regardless, the kids were very well behaved … even my little Buddy surprised me.

From there, we walked up to the 32″ telescope (pictured above).  However, due to inclement weather, we were unable to view the night sky.  Instead, the volunteer spoke about the dynamics of the scope, about adaptive optics, and the role the PMO plays in the collection of data for astronomers worldwide.  He spoke for 30 minutes … it was very cold and very late … a few families left early … so I facilitated in moving us along to the 24″ telescope.  Again, the weather didn’t permit sky watching but here, another volunteer explained how the 24″ scope operated … he even moved it around and showed us how it was done in the past (manually with gauges) and presently (digitally with remotes).  The kids loved it when he opened the dome slightly and rotated the dome as well.

The second volunteer did a better job bringing it down to our level and spoke for less time.  Regardless, the kids had a great time and were captivated by the telescopes.  On the drive home, the skies cleared enough for the kids to see the stars.  MeiLi proclaimed enthusiastically, “I see the Big Dipper!  It’s the first constellation I’ve seen and know!”  They are already planning a return trip as soon as our weather is more predictable (it’s just been so strange this year).

March 25, 20094

What a fabulous day! We departed home at 7 a.m. for the drive to Fossil. Despite a few setbacks, we arrived safe and sound just after 10 a.m. where we met with Will Boettner, the Executive Director of the Oregon Paleo Lands Institute. After introductions and a stop in the necessary or lu, we drove the short distance to Wheeler High School whereby we listened to a volunteer as she explained a little about the geology of the area and what we could expect to find.

The fossil beds were formed 30 million years ago when volcanic ash fell during the formation of the present day Western Cascade Range. The ash was washed into the lake basin along with leaves and other plant material, level after level piling up. The ash preserved the leaves long enough for impressions to form under the pressure of the overlying layers.
paleo lands instituteAbout 35 species of plants, most of them belonging to genera that are no longer native to the Pacific Northwest, are found there. The most common plants are alder, maple, beech, dawn redwood and pine in what appears to represent a deciduous hardwood forest. This implies, according to Will Boettner, that the climate at that time was much more moist and more temperate than is presently the case in the shrub steppe and savannah of today.

We spent about an hour ‘excavating’ in the shale behind the high school. Everyone was successful in finding fossils. I was delighted with how intrigued the kiddos were as they diligently picked up piece after piece of shale in hopes of finding a little treasure preserved between the layers. Prior to departing, we were able to browse the many fossil samples that have been found previously, including several amphibians and fish species.

We took a break for lunch … whereby Will shared more about his experiences, the geology of the John Day Basin, and about the community of Fossil. We then proceeded southwest to the Clarno Unit of the John Day Fossil Beds for a guided nature walk through a canyon.

It was a delightful walk. Everyone was entranced by one thing or another. We all had an opportunity to ask questions and explore the region more closely. We saw first hand how the layers of sediment had built up over millions of years and how the rocks formations had changed over time due to weathering. We talked about the impact man has had on the water table in just the past 150 years or so… changing the once temperate, deciduous forest to the dry scrub land of today (mostly Juniper and Sagebrush). Everyone walked away with a new awareness and appreciation of the natural history of our region.

Thank you to Will Boettner of Oregon Paleo Lands Institute for providing such a wonderful learning opportunity for us all.

“Do what you can
with what you have,
where you are.”

~ Theodore Roosevelt