Wednesday, January 15, 2014

The Big Island

Aloha!

We’ve just spent 5 days in Hawaii and will do the islands one at a time because they’re just too beautiful to try to eliminate pictures. In order to deal with extraordinarily poor Internet connection, pictures are downsized to make the process of unloading easier--real pictures are much nicer!!!

Our first stop was the Big Island. While all of the islands were formed by volcanoes, the Big Island has the only active volcanoes. There are 2 considered active, although Kilauea is the only one currently spewing lava into the ocean—increasing the size of the island. Mauna Loa is also considered active, although currently dormant. Mauna Loa is currently 13,677 feet above sea level, but it’s actual height is 56,000 feet above the sea floor—that’s a lot of lava to create part of the Big Island.

Interestingly, there are 5 active, dormant and extinct volcanoes that created the island. The oldest is at the north end of the island and the youngest (Kilauea), at the south end. The Hawaiian Islands are moving north at a rate of about 2 inches a year as part of the Pacific plate. Over several million years, this means that the island has moved over the hole in the Earth’s crust that is spewing lava. When it moves enough, a new volcano is formed and adds to the island at the south end—as Kilauea is. But the island is still moving and a new volcano has formed off the southern coast. It is still a mile below the surface of the water and scientist estimate that it will take 10,000-100,000 years to reach the surface of the water.  Pretty cool stuff!

The first picture is of the Kilauea caldera, with steam spewing from its deepest levels. This isn’t where the lava is coming out at this time—it’s actually coming out of openings on the flank of the volcano and running toward the ocean. To be a caldera, a crater has to be 2 kilometers wide. This one is actually 3 kilometers wide.



Picture 2 shows a view across the caldera. Picture 3 shows a close-up of a steam vent on the caldera floor. As you drive along the crater rim drive, you’ll see steam rising from various spots on both sides of the road, as shown in picture 4. We walked to the edge of one and it felt like standing in a steam room—hot but tolerable. The steam rose from water at the boiling point several feet below ground—wouldn’t want to jump in!






We also visited the Thurston Lava Tube. A lava tube is formed from flowing lava. The outer shell of the lava hardens because it has contact with the air. The lava on the inside, however, continues to flow. When the lava stops flowing, the shell remains and forms a long, tube-like cave. The  Thurston Lava Tube is over 30 miles long, although it has collapsed in many places and you’re only allowed to go through a few hundred yards. Picture 5 shows the entrance to the tube and Picture 6 shows what it’s like to walk inside the tube.




We had to walk through an extinct crater to get to the lava tube and picture 7 shows that it is now a lush tropical rain forest. How many plant species form that rain forest?  7! I expected it would be hundreds or thousands, but not so in this rain forest.  While much of the area around the caldera is rain forest, at the actual rim, it’s a desert, with very little rainfall. 



Could have spent much more time here. Great hiking around the rim and down into the caldera—at least on days when the sulfur dioxide levels allow it!


Next entry—Maui!

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