Monterey Bay Aquarium Research Institute

2012 Climate and Deep-sea Communities Expedition

 

Day 4: Recovering the Benthic Rover
June 17, 2013

The weather models predicted today to be the calmest of our cruise, so today we recovered the Rover. Like the Mars Rover, the deep-sea Rover II is a self-driving tank that stops at planned intervals to run experiments on its environment. The Rover takes pictures of the seafloor and measures the oxygen respiration of bacteria and small animals living in the sediment. Because the weather was calm, the remotely operated vehicle (ROV) Doc Ricketts dove and worked on the seafloor remotely while the engineers downloaded the data and performed maintenance on the Rover.

Rover image of the respirometry chamber during its most recent deployment. Sensors measure oxygen concentration in the chamber every 15 minutes.

As with any ship work, it’s essential to make the most of the available working space. After the Doc Ricketts came up, we had to process the cores of deep-sea sediment collected by the ROV on the seawater tables, but also make sure there was plenty of clean, dry space for working on the Rover. Before starting processing cores and running water over big chunks of mud in the sieves, we put up a plastic divider between the benches so no mud could splash over to the electronics.

Making the most of the working space on the Western Flyer. The left side has sieves, spray bottles and buckets ready for processing gallons of splatter-prone deep-sea mud. On the right, Alana Sherman and Paul McGill check the electronics that run the Rover.

—Crissy Huffard

Previous log Next log

 Logbook

Day 6
June 19, 2013
Preparing for the next mission

Day 5
June 18, 2013
The sediment event sensor

Day 4
June 17, 2013
Recovering the Benthic Rover

Day 3
June 16, 2013
Making the most of good weather

recovering the mooring Day 2
June 15, 2013
Deploying the elevator

camera tripod Day 1
June 14, 2013
Weathered out

 Equipment

R/V Western Flyer

The R/V Western Flyer is a small water-plane area twin hull (SWATH) oceanographic research vessel measuring 35.6 meters long and 16.2 meters wide. It was designed and constructed for MBARI to serve as the support vessel for ROV operations. Her missions include the Monterey Bay as well as extended cruises to Hawaii, the Gulf of California, and the Pacific Northwest.

ROV Doc Ricketts

ROV Doc Ricketts is MBARI's next generation ROV. The system breaks new ground in providing an integrated unmanned submersible research platform with many powerful features providing efficient, reliable, and precise sampling and data collection in a wide range of missions.

Long-term sediment trap

Sequencing conical sediment traps, each with an effective mouth opening of 0.25 m2, are moored at 600 meters and 50 meters above the bottom at 3,500- and 4,050-meter depths, respectively. Trap sequencers are programmed to collect sinking particulate matter in sampling cups every 10 days. In the laboratory, the collected particulate matter is analyzed in duplicate for total and inorganic carbon.

Push cores

A push-core is a clear plastic tube with a rubber handle on one end. Just as its name implies, the push core is pushed down into loose sediment using the ROV's manipulator arm. As the sediment fills up the core, water exits out the top through one-way valves. When the core is pulled up again, these valves close, which (most of the time) keeps the sediment from sliding out of the core tube. When the cores are brought back to the surface, scientists typically look for living animals and organic material in the sediments.

Benthic Rover

The Benthic Rover is a mobile physiology lab. In a series of experiments, the rover measures how much oxygen seafloor animals are using. Precise motors lower two 30-centimeter-wide (12-inch) sample chambers into the sediment, where probes record oxygen levels. Two acoustic scanners use ultrasound (in 4-MHz pulses) to look 10 centimeters (four inches) deep into the sediment for large animals, such as worms.

High-frequency suction samplers

This midwater toolsled contains a High-Frequency Suction Sampler (HFSS). You can see one of the 12 collection buckets in this image. This sampler acts like a vacuum cleaner sucking up samples and depositing them into one of the 12 buckets.

Benthic elevator

The benthic elevator allows us to carry more than the ROV itself can carry. Loaded with sediment enrichers, it is deployed from the ship before the dive and free-falls to the bottom where the ROV pulls the equipment from the elevator for use. After the ROV is recovered, the elevator anchor's acoustic release is triggered from the ship, and the elevator freely ascends to the surface and is recovered.

Camera mooring

The time-lapse camera consists of a Benthos 377 camera mounted on a titanium frame at an angle of 31 degrees from horizontal with the lens approximately two meters above the seafloor. The camera is equipped with a 28-millimeter Nikonos lens, providing angular coverage of 50 degrees in the horizontal and 35 degrees in the vertical plane, and holds 400 feet of 35-millimeter color-negative film. Up to 3,500 images can be collected in 4.6 months. Two strobe lights, one mounted on either side of the camera housing, illuminate approximately 20 square meters of the seafloor beginning at a distance of 1.8 meters from the camera frame and extending approximately 6.5 meters from the base of the camera frame. In June 2007 a high-resolution digital camera was added to the frame.
 Research Team

Ken SmithKen Smith
Senior Scientist, MBARI

Ken is an open-ocean ecologist with 40 of years experience going to sea and studying extreme ecosystems ranging from the deep ocean to Antarctic icebergs. The main thrust of his research is to understand the impact of a changing climate on deep-sea and polar ecosystems. On this cruise, he will coordinate the deployments of autonomous instruments to continue long time-series studies at Station M on the Monterey Deep-Sea Fan at 4,000 meters depth.

Alana Sherman Alana Sherman
Electrical Engineer, MBARI

Alana specializes in instrumentation. On this cruise she will be deploying three instruments: the Benthic Rover, the time-lapse camera tripod, and Lagrangian sediment traps.

John FerreiraJohn Ferreira
Mechanical Engineering Technician, MBARI

John will help with all the mechanical maintenance and repair of the Benthic Rover, the sediment traps, and the seafloor camera tripod.

rich henthorn Rich Henthorn
Software Engineer, MBARI

Rich has been at MBARI since 2000 working on many types of projects, but mostly writing software for MBARI's autonomous vehicles. On this cruise Rich is responsible for the control system on the Benthic Rover. The Rover will be retrieved from the seafloor and then redeployed for six more months.

Crissy HuffardCrissy Huffard
Senior Research Technician, MBARI

Crissy is a senior research technician in Ken Smith’s lab. On this cruise she will be supporting shipboard operations and instruments, and overseeing samples collected from the sediment traps.

Paul McGill Paul McGill
Electrical Engineer, MBARI

Paul specializes in underwater vehicles and instrumentation. On this cruise he'll help prepare, deploy, and recover the drifters, crawlers, and landers being used to study the deep ocean at Station M.

Henry Ruhl Henry Ruhl
Head, DEEPSEAS Group
National Oceanography Centre, Southampton

Researching the links between climate variation and deep-sea ecology has been a primary focus for Henry. In particular he's interested in understanding how changes in climate are related to the role of the deep ocean as a carbon sink. During the cruise he will be researching the abundance and distribution of animals on the seafloor, as well as their respiration rates using specialized chamber systems. Respiration is a good indicator of carbon utilization and provides key input into estimates of carbon flow and the importance of biodiversity at the seafloor.