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May 4, 2021
By Philip S. Prince Fold-thrust belts developed in sedimentary rock sequences produce interesting and complex patterns on Earth’s surface. These patterns become even more complex and intriguing when the folded and faulted sedimentary layer sequence contains internal structures that pre-date thrust belt development. A particularly outstanding example of this effect is the Talar Syncline of the Makran fold-thrust belt, in which an extensional growth fault depocenter has been folded, uplifted, …
December 13, 2019
On December 15, 1989, a pilot who had flown a 747 passenger jet all the way from Amsterdam was looking forward to landing in Anchorage. There, he would take a short break before continuing to Tokyo.
March 22, 2018
Yesterday we took a trip to Mt. Teide, Tenerife’s highest point and an active volcano. Teide’s peak is about 3,700 meters (12,000 feet) above sea level. While not very tall by mountain standards, from the base of the seafloor to the tip of its peak, Teide is 7,500 meters (24,600 feet) tall, making it the third tallest volcano in the world (Mauna Kea is the tallest).
October 13, 2017
Two years ago, before I became a graduate student, I would have never thought I would be at sea on a seismic research expedition.
June 19, 2017
We spent the last week on a large-scale mapping project covering several miles in distance. Just before that started, I took 35 students on a 1-day trip through Yellowstone National Park, and I’m told that people in the park were asking if I was an official tour guide since I was walking the students through the geology at various stops.
June 13, 2017
Shiprock in New Mexico is a classic example of a volcanic neck. It is a vertical column of volcanic rock that sticks up around the surrounding landscape, with dikes that radiate from the central core. Although ours isn’t as high, we have a literal version of Shiprock in our field area.
June 12, 2017
In my last post, I showed off some of the metamorphic rocks we can see that formed about 1.8 billion years ago during a mountain building event known as the Big Sky Orogeny. The textures in these rocks are fascinating. They contained a variety of protolith lithologies, making them immediately complicated. They are highly deformed; so one lithology bends into another very rapidly.
June 8, 2017
Here’s an intro to some of the rocks we’re actually mapping. On our first day in the field, we walked the section of rocks exposed in this area from oldest to the youngest rocks we had time to get to. Students were literally standing on 2.5 billion years or so of Earth’s history – more than half the time this planet has existed.
June 7, 2017
Although the area where we’ve been mapping is pretty dry, dealing with wildlife in various forms has been pretty constant. This is potentially on my mind as today I set my personal best by peeling 6 ticks off of me. Our camp is pretty large and has broken into separate groups, each group shifting between different areas.
One of the things you can’t help but notice once you come to Montana is the sky. According to my daily topo maps, most of my time is spent in-between contours 5600 and 5800, so literally 1 mile (1.8 kilometers) above sea level. I haven’t traveled enough myself to know if you get the same effect around the world, but once you come to a field camp here the phrase “big sky country,” one of the official nicknames for Montana, definitely fits.