(reminds me of the Giant's Causeway)
This spectacular columnar joint pattern in lava exposed in Alaska's Suemez Island formed when the lava flowed next to a glacier about 700,000 years ago. CREDIT: Susan Karl, U.S. Geological Survey
Posted on 06/08/2013 10:58:58 AM PDT by SunkenCiv
In Alaska, scores of volcanoes and strange lava flows have escaped scrutiny for decades, shrouded by lush forests and hidden under bobbing coastlines...
Some of the unusual finds Karl and Baichtal have uncovered include a maar lying 295 feet (90 meters) underwater near Cape Addington, about 40 miles (65 km) west of Craig, Alaska. Maars are bomblike craters blasted out when magma rising underground hits groundwater and explodes. The maar is about 13,800 years old, Baichtal said. Sea level was 394 feet (120 m) lower when the maar formed.
The latest find is an underwater volcano in Behm Canal, where hundreds of thousands of tourists on cruise ships have sailed by New Eddystone Rock, an eroded volcano. Behm Canal is dotted with cinder cones, both onshore and below the water.
East of Ketchikan, a basalt flow lapped onto a 42,000-year-old beach, preserving shells, pinecones, pine needles and pollen. Barnacle plates sitting on top of the lava are about 13,000 years old, Baichtal said. The whole package now sits about 260 feet (80 meters) above sea level, hinting at how much Earth's crust has bobbed up since the last ice age.
"It gave us how much isostatic rebound there is today. That's one of those really great days in geology. You couldn't have written a better script, and there's a lot of those kind of things coming out of there," Baichtal said.
(Excerpt) Read more at livescience.com ...
This spectacular columnar joint pattern in lava exposed in Alaska's Suemez Island formed when the lava flowed next to a glacier about 700,000 years ago. CREDIT: Susan Karl, U.S. Geological Survey
Material linked to ancient volcanic eruption in Alaska
Alaska Science Forum | Thursday, January 17, 2013 | Ned Rozell
Posted on 01/19/2013 8:13:22 AM PST by SunkenCiv
http://www.freerepublic.com/focus/chat/2979827/posts
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| GGG managers are SunkenCiv, StayAt HomeMother & Ernest_at_the_Beach | |
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Thanks machogirl. |
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Who knew! I will have to go back and check it out, I guess.
Thanks!
Textbook worthy photo!
Welcome Civ
That's about the same time a comet hit, eh?
Been to Alaska twice. Need to go back as many times as possible.
Thanks.
Basalt flows is neat stuff. Devil’s Postpile in California has similar type flows.
Weird coincidence, eh? ;’)
Almost home, Alaska was sunny, cloudy, rainy and bearable. :-)
We are 12 hours away from being on our doorstep.
The glaciers are still alive and calving.. and fortunately still close to 2,000 miles, for now..
next trip .. Panama canal
How beautiful! I’d love to see it in person.
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