2011 - R/V Wecoma, 2011 Crew, Deployment, LDEO, SIO

Cruise Summary

October 28, 2011 William Hanshumaker Leave a comment

Dr. Robert Dziak contributed this cruise summary:

“The OBS deployment cruise was an unqualified success. Our
highly efficient team of sea going professionals was able to maintain a
brisk deployment schedule and completed all 25 ocean bottom seismometer
deployments within 8 days. We averaged 3 deployments a day, including
time for instrument surveys to derive their precise locations. The only
thing that suffered was our sleeping habits, but it was well worth it!
We also wish to express our gratitude to the Captain, crew, and Marine
Tech of the Wecoma for their hard work that allowed our project to be
successful”

“All 25 SIO and LDEO instruments were deployed with sites prioritized
prior to the cruise in consultation with the community to focus on
different scientific questions. This prioritized sequence was further
modified prior to the cruise to accommodate recommendations from the
Oregon Fishermen’s Cable Committee (OFCC), The Oregon Trawlers
Association, the Quilete and Quinault tribes, and the Canadian Trawlers
Association, all of which represents the various fishing communities on
the Oregon, Washington and Canadian continental margins. Of the 25
instruments deployed, one SIO Abalone instrument lost its anchor as it
was being deployed. Another Abalone was deployed in its place as a spare
anchor was sent to Newport during the cruise. We returned to port
briefly after deploying the first 24 instruments, and returned to the
site to deploy the lone remaining Abalone. All instruments will remain
on the seafloor until the summer of 2012.”

2011 - R/V Wecoma, 2011 Crew, Missions

Last Day at Sea

October 21, 2011 William Hanshumaker Leave a comment

We deployed the 24th seismometer at 9: this morning. The atmospheric pressure is dropping and the seas are rising, making the deployments more challenging. The roll of the ship increases the difficulty of both getting the seismometer to the rail and successfully releasing it over the side. We are heading back to Newport to pick up another anchor plate for one that we lost a couple of days ago. We’ll be doing a “touch and go”, without even putting out the gangplank. Fortunately, the last site is close to Newport.

At 9:50, seven of us met in the wheelhouse for a live Skype broadcast to HMSC. Tracy Crews organized “Career Day” for high school students and we responded via two way video to student questions from the Hennings Auditorium. Our virtual presence was projected on its large screen.

Bob Dziak – Chief Scientist – Professor, Marine Geophysics, OSU, – What are you studying out there? What’s it like working at sea?

Dave Ogorman – Marine Instrumentation Engineer, Wecoma – How did you choose this career?

David Gassier – Ocean Research Engineer, Lamont-Doherty Earth Observatory, Columbia University – What is your background? Is there a specialized degree in Ocean Engineering?

Del Bohenstiehl – Co-chief Scientist – Associate Professor – North Carolina State University – What do you like most about being a scientist?

Matt Fowler – Mooring and Instrumentation Engineer – Research Assistant, OSU – What is your background? What do you enjoy most about your job?

Martin Rapa – Development Engineer, Scripps Institute of Oceanography – What did you have to consider when designing an underwater seismometer?

Tag lines are used to stablize the deployment

Matt is struggling with a jammed quick release mechanism

2011 - R/V Wecoma, 2011 Crew, Deployment, Seismometers

A Day in Transit

October 20, 2011 William Hanshumaker Leave a comment

Following the continental margin, the Wecoma cruised south at about 10 knots for most of the day. The seas picked up slightly, and there were light scattered showers. We deployed another Abalone seismometer at 4:30, and it was on the bottom by 5:30. We will be deploying the last Cascadia seismometer at 1: am.

2011 - R/V Wecoma, Deployment, Seismometers

Thursday Morning

October 20, 2011 William Hanshumaker Leave a comment

The seas are very calm this morning, making for an easy deployment of the Abalone seismometer. We are directly offshore from the mouth of the Columbia River, in a depth of 2678 meters.

2011 - R/V Wecoma, Deployment, Missions, Seismometers

Off the coast of Washington

October 19, 2011 William Hanshumaker Leave a comment

Wednesday afternoon, October 19^th – Off the coast of Washington at the edge of the continental margin

We just deployed another Cascadia seismometer. It will take 65 minutes to reach the ocean floor, 2630 meters below. It will take another hour to conduct the acoustic survey, as the Wecoma cruises in a kilometer and ½ circle overhead.

Wecoma’s crane is lifting the seismometer over the side

It takes at least 5 crew members to deploy a seismometer

2011 - R/V Wecoma, Deployment, Seismometers

Wednesday’s Sunrise

October 19, 2011 William Hanshumaker Leave a comment

The weather has deteriorated somewhat, but is still serviceable. We deployed two seismometer last night and another one this morning. Since we are in deeper water, it takes longer for the seismometer to reach the bottom. A acoustic survey is immediately conducted to determine its exact location in three dimensions; latitude, longitude and depth. The Wecoma circles the seismometer location as the acoustic release sends signals to the ship.

2011 - R/V Wecoma, Deployment, LDEO, Seismometers, SIO

A Beautiful Monday at Sea

October 18, 2011 William Hanshumaker Leave a comment

We have traveled north to test two Cascadia seismometers that were deployed earlier during the first leg during July. A specific frequency of sound (between 9 and 13 kilohertz) is sent down to check if the instrument package is working. Sometimes a fishing trawl can flip over the seismometer, rending it useless. If the instrument is working, it responds with a series of audio chirps that are picked up here on the Wecoma.

So far we have deployed five Cascadia and four Abalone seismometers. Another five are scheduled for deployment through the night.

2011 - R/V Wecoma, Deployment