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Thank you thank you thank you

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On June 1, we arrived in port in Kodiak, Alaska, marking the end of our expedition. Kodiak greeted us with spectacular vistas of mountains and lush green hills. It’s not called the Emerald Isle for nothing!   Views of Kodiak on our way into port Despite a late departure and some rough weather, it was an enormously successful trip. We collected a suite of fabulous datasets that will help us understand the formation of this 6000-km-long chain of volcanos that have formed across the Pacific plate over the last 80 million years.   Many mysteries remain about the water-covered parts of our planet, particularly in remote regions like our study area, despite the fact that they host truly gigantic structures. Jimmu Seamount is nearly as tall as Denali, the tallest mountain in North America, and much more massive!     Comparison of bathymetry across Jimmu Seamount and elevation across Denali Collecting data that enables us to unravel Earth’s mysteries r

During the transit...

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A packed house for the finals of the ping pong tournament. Luan Nguyen squares off against Tim Kane. Following the successful completion of our program, we are transiting ~3000 km to port in Kodiak, Alaska.     This trip took us back across the date line and along the Aleutian Islands and Alaska Peninsula, where we were treated to glimpses of distant, rugged mountains shrouded in clouds. Our newly collected data has kept us very busy. The long trip enabled us to complete onboard processing of seismic and bathymetric data, discuss initial observations from the data and share our preliminary results with the rest of the Langseth ’s crew.   We are seeing all kinds of interesting and unexpected things in the data.  We may even get close to completing the cruise report before we come into port, which would a minor miracle. Mei Liu and her model OBS But the transit has also given us a chance for some recreation now that our main data collection duties are finished.  

Calling OBS home before the weather

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Luan nabs a returning WHOI OBS Yesterday, we finished recovering 29 ocean bottom seismometers deployed along the Emperor Seamount Chain, thus completing our field program in the Emperor Seamount Chain.   We were blessed with a long period of excellent weather for collecting data on the 15-km-long seismic streamer and for most of the OBS recoveries.   Good weather is particularly important for the latter.   Despite all of the technology that enables us to put a seismometer on the seafloor in water depths of 6300 m (~19,000 ft!) and send them commands to come back to the ocean surface, our method of fetching them from the ocean onto the ship is quite basic, but still impressive! The ship’s mates drive this large vessel right up next to the floating OBS, and people reach out and hook the OBS from the starboard deck using a long stick!   We then use a crane to hoist them out of the water.   This procedure becomes much more difficult in rough weather. Maneuvering the vessel is more cha

The Emperors among us

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The main lab's view of the last seismic reflection data being collected. Overseeing  them are  drawings of Emperor Jimmu and Empress Suiko. Finishing the seismic reflection acquisition part of our experiment, we find ourselves south of Jimmu Guyot and near Suiko Guyot. The term ‘guyot’ refers to a flat top seamount that was first named by Harry Hess, a pioneer in developing our current understanding of plate tectonics. These features have a similar morphology to the plateaus found in the Western United States with both having a flat terrain on top that is raised above with surrounding areas often by steep slopes. The Hawaii-Emperor Seamount Chain is a great example of the formation of guyots along volcanic chains. Active volcanism is found on the youngest in the chain, currently at the Big Island of Hawaii which sits atop the central Hawaiian hotspot, a small spot in the plate that fuels the volcano from great depths. As the Pacific Plate slowly but steadily moves to the no