NOTE: This portion of our trip to Costa Rica with annotations and photos is not finished. The scenes and captions that you see in this blog are the last images of the journey. So that you can view the vacation chronologically when you first open the blog, in the order in which the activities took place on the trip, I have to edit the blog of last event first, and move backward in time to our first activities in Costa Rica last. (Confusing, isn't it!)
Martino Hotel and Spa
With three days left in our vacation, we decided to move to a resort close to the airport. The Martino Resort and Spa is a five-star hotel with the trappings of luxuriance. The unit had every thing from tennis and basketball courts to a separate gym facility that provided 39 different exercise machines. Our room included a king-sized bed and extensive wooden paneling, even for the bathroom counter!
Hole-in-the-Ground
We traveled to eastern Oregon to explore the impact of volcanism on the landscape. Oregon has the deepest concentrations of lava in the world with depositions over a mile deep in the northeast corner of the state. Hole-in-the-Ground was formed 15,000 years ago when magma came into contact with ground water. Steam driven volcanic explosions created this tuff ring (maar), which is almost a mile in diameter and 500 feet deep. (The image is a panorama; click to open it at full width and scroll.)
Fort Rock
Fort Rock was created when magma rose to the surface and encountered the wet muds of a lake bottom. Powered by steam, molten basalt was blown into the air, creating a fountain of hot lava particles and frothy ash. The blobs of hot lava and ash rained down around the vent, cooled in the lake waters, and formed a saucer-shaped ring (tuff ring) sitting like an island in the lake waters. Native Americans once had to canoe to and from the island. This is hard to imagine in the dryness that is now this region!
Thousands of years ago, Fort Rock Cave was a tuff-ring island, and the cave was formed by water. Wind driven waves eroded softer material from under harder rock to create the cave. It was a similar erosion that can be seen on Fort Rock in the distance. There are over 40 tuff-rings (maars) in this basin.
Derrick Cave
Derrick Cave is the largest lava tube in the area. It is 30 feet high and 50 feet wide at the widest point, and 1/4 mile long. The ceiling has collapsed in two places. From this main entrance, one can see one ceiling collapse in the background.
A few feet inside the cave reveals a steel-rimmed door. In the 1960s, when the U.S. and Russia were at odds, Derrick Cave was a designated a nuclear fallout shelter. It was supplied with food and water for central Oregonians to escape a nuclear holocaust. (The "skylight" at the rear of the lava tube indicates a collapsed roof.)
The "living room" of the cave was about 100 feet deep and 20 feet wide at the widest point. The idea of central Oregonians living in these cramped quarters for years, waiting for radioactivity to decrease, was more onerous than facing the threat of nuclear fallout! This was another reason for abandoning the project.
Crack-in-the-Ground
We have driven eight miles on a dirt road from the small town of Christmas Valley, Oregon. Carol puts on her hiking boots for the one-third mile hike to the Crack-in-the-Ground.
The eruptions from the Four Craters Lava Field, seen in the background, were accompanied by a slight sinking of the older rock surface, which created the Crack-in-the-Ground. It is a shallow "graben," or sinking of the earth, a tension fracture in basalt. (A larger graben in southeastern Oregon is a vertical subsidence, or sinking, of one mile of the earth from the upper to lower edge!)
It is estimated that the crack has remained open for a thousand years. Open cracks or fissures in the earth's surface are not uncommon; they occur fairly often as the result of earthquakes or volcanic activity, but they usually become filled with rock rubble or lava and disappear in a very short time. A large fissure that stays open for hundreds of years is, therefore, a rare feature.
NOTICE !!
THE FOLLOWING POSTS ARE TWO YEARS OLDER (2006), THAN THE PRECEDING POSTS LISTED ABOVE, (2008). WE ARE RESUMING THE BLOG BECAUSE OF RECENT TRAVEL THAT INVOLVED ENGAGING SCENARIOS ILLUSTRATED BY NUMEROUS PHOTOS. THIS BLOG IS THE BEST WAY TO REACH CURIOUS PARTIES INSTEAD OF SENDING LENGTHY E-MAILS TO INDIVIDUALS WHO MAY NOT BE INTERESTED.
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