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After all of my exciting adventures these past two weeks it is time to say goodbye because my tectonic tour has come to a close. I am heading back home tomorrow to spend the rest of my summer swimming and preparing for college. I had an awesome time learning about the plate boundaries and getting to see locations all over the world. Thanks to everyone who has been reading my blog these past few weeks and I recommend that you choose to take a tectonic tour sometime in the future. Thanks for listening! Goodbye!

- Katherine

Mid-Atlantic Ridge

For our last stop we made our way by plane to the coast of Brazil and then by boat to the middle of the ocean at 1 deg 5'12.92"N and 30 deg 45'55.65"W to see the Mid-Atlantic ridge, the longest mountain range in the world. From our boat John told us that the Mid-Atlantic ridge is a divergent boundary (plates are moving apart) similar to the Red Sea only it is under water. It works like this:

Rising convection currents lift the crust forming a mid-ocean ridge and as the plates pull apart this ridge cracks and magma pours into the fissure. The magma solidifies and the process repeats itself. This type of plate boundary creates the new ocean crust while convergent boundaries destroy ocean crust. This creates underwater mountain ranges which can be found at the Mid-Atlantic Ridge. It also creates shallow earthquakes activity and volcanic eruptions in the form of fissure eruptions.

http://go2add.com/images/Volcanoes/DivergentBoundary.jpg

We spent a night on our boat as we headed back to the Brazilian coast and  in the morning we had some time to go deep sea diving and admire all the amazing creatures in the Atlantic Ocean. It is amazing to think that that the Mid-Atlantic Ridge spreads 2.5 cm per year and goes straight through the island of Iceland! I had to say goodbye to all of the wonderful people I met on my tectonic tour including Jen and our tour guide John. I wish these two weeks weren't over but once I make it to Brazilan coast it will be time to head home...

- Katherine

Krakatoa Disaster

After our time in Chile we gathered our bags and got on a plane set for Jakarta, Indonesia and the volcanic island of Krakatoa. We arrived in Jakarta and spent some time looking around Indonesia's capital. Jakarta is a beautiful city that I would love to have a chance to spend more time in. The following morning, we took a boat to the site of the infamous Krakatoa volcano which lies at 6 deg 9'17.03" S and 105 deg 26'30.09"E. The volcano is a case of a convergent subduction boundary involving the subduction of the Indo-Australian Plate under the Eurasian plate. There was no continental crust in the area that the two plates subducted, only ocean crust so the older ocean crust subducted under the newer crust. This crust heats up and begins to melt forming magma chambers that can rise to the surface and create volcanic eruptions. These eruptions create a chain of volcanic islands like the Krakatoa Islands.

http://upload.wikimedia.org/wikipedia/commons/6/67/Map_krakatau.gif

It was amazing to travel to Ujung Kulon National Park and all of the beautiful plants and animals were so exotic. It was interesting to see the volcano and learn all about the history of its eruptions. The most famous explosion of Krakatoa was in 1883. A series eruption began in May and lasted all the way until  a huge explosion and the destruction of the major island of Krakatoa in August. Before this huge eruption there was a lot of seismic activity as the plates shifted and about 3 months before steam started to vent out. The explosion that blew the island apart was caused by super-hot steam that was created when walls of the volcano ruptured and let water into the magma chamber.

The Island exploded with the force of 100 megatons and was heard as far a way a Madagascar! Huge 131 ft Tsunamis hit the coast of Java and Sumatra destroying 163 villages and killing thousands. Ash from the explosion rose 50 feet int the air and effected the weather the next year.

The Krakatoa volcano continues to be active and explode quite often every year. A new island called Anark Krakatoa (Child of Krakatoa) was created and has been growing in the same place the old island of Krakatoa was. Anark Krakatoa grows about 5 inches per week and is an amazing island.

An eruption in 2008
http://upload.wikimedia.org/wikipedia/commons/4/44/Krakatoa_eruption_2008.jpg

It was so cool to see this scientific and historical wonder but this also means my trip is almost over! One more stop until my tectonic tour comes to an end.

- Katherine

Tupungato Volcano

After our day of skiing and learning about convergent subduction boundaries we spent the night at our hotel and then got up in the morning. We boarded a big Greyhound bus and drove north toward Santiago to visit Tupungato, a massive extinct volcano that rises 3,300 feet above the neighboring peaks and lies at 33 deg 21' 16" S and 69 deg 46' 7" W. We also saw Tupungatito (little Tupungato) which is still active and has had at least 18 eruptions since 1829. It is southwest of Tupungato and also quite massive. These mountains are in Provincial Park and are very difficult to climb. We went on some day hikes in the park and looked all the interesting species of plants and animals. These two volcanoes were created because of the subducting Nazca plate and the Tupungatito' last eruption was in 1986. There was recently a 4.6 earthquake at the summit in 2009 and are often small shocks around the area.


http://images.travelpod.com/users/anaronnie/1.1263206063.tupungato-volcano.jpg

We left the park and drove back to Rancagura so we could spend the rest of the day at our leisure and packed our bags for the next stop in our tour around the world.

- Katherine

The Andes in Chile

We spent a few more days hiking around in Nepal but yesterday we boarded a plane set for Rancagura near the Andes Mountains. We made it to Chile yesterday and spent this morning visiting museums until lunch time. We then gathered up our ski equipment and went into the Andes at about 34 deg 4'30.75"S and 69 deg 550'26.99"W to look for some powder. The skiing was great and when we were all exhausted we went into the lodge for a cup of hot chocolate. John took the time to explain the science of the Andes.

Similar to the Himalayas, the Andes are a convergent boundary so the plates are moving toward each other but they involve subduction and oceanic crust. I explained a little about convergent subduction boundaries in my last post but after visiting the Andes I have a lot more to explain. When two plates hit in a spot where there is continental crust on one plate and oceanic crust on the other, the oceanic crust subducts under the continental crust because it is thinner and less dense. As the oceanic crusts descends into the mantel, it heats up and around 100 miles under the plate starts to melt. This melting results in magma chamber that rises up to the surface and causes volcanic eruptions. According to John there are many volcanoes in the Andes as a result of the Nazca plate subducting under the South American plate. This subduction created the volcanic Andes Mountains and is continuing at a rate of 3 inches per year.



https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgAa4yPjEk7-qO9aQHC9tCm8tGob9L83NkZT-fQT6lEAyDQPHZWKQiQYmQROdTFcJjMaqDE4NjLh-xjDUi6jftz4khNACaISgVI0Z3Pg8ThP1y6-Et_3AV5tf-nre4WWtioq9-XHsw3osU/s1600/Convergent_Boundary+1.jpg

 The results of a convergent subduction boundary are a zone of shallow earthquake activity, sometimes a ocean trench right off the continent, and volcanic eruptions a few miles in from the shore. You may have heard about the 8.8 earthquake Chile had in February 2010 which was right near where I am staying. The death toll for this terrible earthquake was around 560 and many homes and buildings were destroyed. Like almost every other area on a plate boundary, Chile experiences many small and large earthquakes.

After our ski trip we headed to our hotel for a big group dinner and then went to bed awaiting our next tectonic adventure.

- Katherine

Life In the Himalayas

The San Andreas fault was amazing but I couldn't wait to be on my way to Nepal to see the Himalayan Mountains. My tour boarded a plane on Tuesday and lucky for me my new friend Jen and I got to sit next to each other. After a night flight that I barely slept on, I landed in Pokhara, Nepal,which lies at 28 deg 15'4 49.00" N and 83 deg 58' 21.2" E. I was exhausted but ready to see the mountains. We got the first day to sightsee and spent the night in a nice hotel that served delicious local cuisine and went to bed looking forward to what would be in store for us tomorrow. 

In the morning we woke up early, grabbed our hiking boots, and headed for a scenic and informational hike through the gorgeous Himalayas. John quickly explained that the Himalayas were one of his favorite places because they are a tectonic paradise. He said they are a continental collision boundary that has been active for the past 50-55 million years.

http://www.uwsp.edu/geo/faculty/lemke/geog101/images3/18r_india_asia_collision.jpg

A continental collision boundary is one in which two plates are moving toward each other and when they hit mountains are formed. Many collision boundaries involve continental and ocean crust so when the two plates hit the thinner ocean crust goes under the larger continental crust which is called subduction. The Himalayas are an interesting convergent boundary because they formed when the continental crust on the Indian and Eurasian Plates hit. One plate can't subduct under the other because they are too thick so they hit and are raised up forming mountains. The results of a continental convergent boundary are some shallow earthquakes as the plates collide, deformed rock, and large mountains.



The Himalayas have some shallow earthquakes as are common in continental convergent areas which have been considered some of the strongest earthquakes in the world and really effect the people living in Nepal and India. The Himalayas have had four major earthquakes in the past century, the most famous one being here in Nepal in 1933. This earthquake killed thousands of people and several more earthquakes have occurred since then in Nepal. In the India Himalayas there have also been many earthquakes such as the Kinnaur Earthquake in 1975, the Darchula Earthquake in 1980, and the Uttarkashi Earth quake in 1991. Every year the Indian Plate pushes the Eurasian plate northward 2 cm so the earthquakes are not going to stop anytime soon!

It was fascinating to learn about the problems with earthquakes that the people living in the Himalayas face and I loved our scenic hike through the mountains. Here is a picture of the us in the mountains:

http://www.destination360.com/asia/china/images/s/china-himalayas.jpg

http://www.destination360.com/asia/china/images/s/china-himalayas.jpg

I can't wait to see where we are going  next!

- Katherine



San Andreas Fault In California

After our fascinating tour of  Egypt and the divergent boundary around the Red Sea, we boarded a plane headed to San Fransisco, California. I loved being in Egypt for a few days but it felt good to be back in the US near home. John said that we were right on the San Andreas fault that lies on the Pacific Plate and North American Plate at 37°38'27.40"N 122°29'0.18"W.

This boundary is a transform boundary which means that the two plates slide against each other. According to John this is why California has so many earthquakes, it lies right on a major fault line! Lucky for the people in California, transform boundaries don't cause volcanoes because there is no convection of rising magma or subduction of plates to cause an eruption, just a lot of shallow earthquakes.

A lot of the mountains and valleys in California have come from the movement of the San Andreas fault because as it moves rocks are displaced making high points and low points. A large trench can be seen where the fault line is. California has a history of seismic activity because of the San Andreas fault. Some of the famous earthquakes that came from the fault were the 1857 Fort Tejon earthquake, magnitude 7.9, the 1906 San Francisco earthquake, magnitude 7.8, the 1989 Loma Prieta earthquake, magnitude 6.9, and the 2004 Parkfield earthquake, magnitude 6.0. The San Andreas fault has existed for 15-20 million years and studies show that large earthquakes have occurred about every 150 years but thousands of small ones occur every year around the San Andreas fault.

After we learned all about the fault we traveled to some of the locations where you can see it and then went home to have dinner and get ready to go on our next adventure tomorrow. Here is a picture of one of the places we went:

 

- Katherine

Picture Sources:

http://en.wikipedia.org/wiki/File:MORMON_ROCKS_San_Andreas.jpg

http://geology.com/articles/images/san-andreas-fault-map.jpg

A Trip to the Red Sea

After a long and boring flight I have finally made it to Safaga, Egypt, the first stop on my tectonic tour!  In the morning I met my tour guide, John, and the other people I will be spending the next two weeks with. We are all similar ages so I am sure we will have a great time touring the world together. This morning, we ate a delicious breakfast and headed out on a fishing boat into the Red Sea.

According to John the Red Sea lies at 27 deg 01 min 6.31 sec N and 34 deg 38 min 50.43 sec E and is right on the border of the Arabian and the African tectonic plates. The two plates have been moving away from each other for millions of years which has created the Red Sea. John said this is called a divergent boundary and it worked like this:

Mantel pushes up against the thick crust of the earth creating a slight bulge in which cracks form as the two plates pull apart. As a rift forms, the crust on either side of it slides down to fill the opening rift and creates a valley. In the early stages of this process linear lakes form as streams and rivers feed into the rift and as the rift grows wider and deeper it can drop below sea level. When this happens large seas are formed such as the Red Sea. John said the rift the Red Sea has been widening for almost 30 million years! There are some volcanoes around the Red Sea because as the rifts form sometimes magma can squeeze up through the cracks and erupt. There are also some earthquakes that happen around the Red Sea as the rift widens. These earthquakes tend to be milder than earthquakes found in locations with other kinds of plate boundaries. The main feature of a continental divergent boundary is a widening rift that is filled with water to make lakes and eventually oceans.

Earthquakes and volcanic eruption happen often around the area of the Red Sea as the crust cracks and magma rushed up and causes an eruption. The volcanoes and earthquakes cause some damage but the earthquakes are usually mild. The last earthquake in the Red Sea was a 4.6 on September 13 2010.

After our fascinating day learning about the Red Sea we headed back to land and spent sometime wandering around Egypt getting to know the city of Safaga. The markets were beautiful and Jen, another women on my tour, and I spent the evening visiting museums and sightseeing. At night I went to bed excited to see where we would be heading next on our tour.

- Katherine

Source of Picture:
http://www.google.com/imgres?imgurl=https://thegeosphere.pbworks.com/f/1269229385/diverg.jpg&imgrefurl=https://thegeosphere.pbworks.com/w/page/22058923/Plate-Tectonics-Final-Map-Project&usg=__dJDdT4KzAx1QXuM5_9W7vckSWeA=&h=839&w=959&sz=148&hl=en&start=0&zoom=1&tbnid=ST3o5p72cBlONM:&tbnh=154&tbnw=176&ei=quWYTZKECcfeiAKap-ycCQ&prev=/images%3Fq%3Dcontinental%2Bdivergent%2Bplate%2Bmovement%26um%3D1%26hl%3Den%26sa%3DN%26rls%3Dcom.microsoft:en-us:IE-SearchBox%26rlz%3D1I7GPCK_enUS367%26biw%3D1419%26bih%3D625%26tbs%3Disch:1&um=1&itbs=1&iact=hc&vpx=351&vpy=92&dur=1062&hovh=210&hovw=240&tx=122&ty=118&oei=quWYTZKECcfeiAKap-ycCQ&page=1&ndsp=18&ved=1t:429,r:1,s:0