With the help of two engineers (Alex Turpin and Matt Fowler), as a Principle Investigator (PI) or Co-PI of the projects, I manage the development of multiple projects and report progress to respective funding agencies including NOAA, the Office of Naval Research (ONR) and the Navy.
Developing autonomous hydrophone systems requires experience in electrical circuit design, programming, and acoustic modeling. Currently five engineering projects are under way. Take RAOS, as an example, which is a Killer Whale monitoring system funded by NOAA. I design the circuit boards, develop software, run extensive lab and field work, and collect data. When it is completed, it will be monitoring the Killer Whale calls off the Washington coast and sending the data to shore via satellite. It is scheduled to be deployed this summer off Friday Harbor on San Juan Island in Washington. I also write proposals requesting funding, present the results and write papers based on the data we have collected.
Dr. Matsumoto off the Washington Coast for the Seaglider & QUEphone Survey April 2015
Even though ~75% of Earth’s volcanic activity occurs below the sea surface, many questions remain on the longevity and acoustic characteristics of explosive seafloor eruptions. To date, only two active eruptions have ever been observed visually in the deep-ocean (>500 m) volcanoes, and then only over time periods of hours to days. The discovery of the actively erupting West Mata volcano in the NE Lau Basin near Samoa (Fig 1) offered a rare opportunity to investigate a deep-ocean, explosive eruption. Video images of West Mata collected by remotely operated vehicle (ROV) provided unprecedented details on the dynamics of gas-driven eruptions at 1200 m depth.
In his recent paper, Dziak et al [2015] present the unique acoustic signatures of West Mata’s two erupting summit vents, called Hades and Prometheus.
To see a video of West Mata erupting under the ocean and for more information on this publication, visit AGU’s Blog.
During its eruption phase, Hades exhibited spectacular 1-2 meter diameter gas filled bubbles of lava (Fig 2) that produced distinctive short duration low frequency sounds when they burst. Prometheus exhibited long duration (1-5 minutes), violent explosions that produced broadband sounds that sometime develop harmonic tones within the explosion record. Over a 6-month period while the hydrophones were recording, the eruption activity at West Mata declined and eventually ceased, allowing us the first view of the demise of a multi-year eruption cycle of a deep-ocean volcano. This paper also provides the background for future work to use these acoustic records of the West Mata to estimate the amount of magmatic CO2 gas that was expelled into the ocean during the eruption.
Maps showing bathymetry of West Mata volcano, with North, West and East Mata volcanoes nearby. Inset is a small-scale view of West Mata showing the locations of actively erupting summit vents (Hades, Prometheus).Video image sequence of a magma gas bubble burst at West Mata volcano summit vent Hades taken by the Jason-2 ROV. First three frames show growth of the bubble; final frame is collapse. (Bottom) Acoustic time series of bubble growth and burst recorded by hydrophone deployed 25 m from vent. Red arrows show time of the four still images in (a).
As a research assistant, I do a lot of data analysis for our group. I’ve been learning a lot about the different under ocean sounds we come across and how to find them on a spectrogram to help answer questions that our scientists put forth, but I’ve still got much to learn. I spent years picking out earthquakes and volcanic tremor in the Lau Basin (a very active area under the ocean near Fiji). I was so focused on locating earthquake and volcanic activity for that project, that I pretty much ignored any other random noises. When picking out earthquakes and volcanic tremor, you have to set your scrolling of the spectrograms (spectrograms are pictures of the sounds on a time and frequency view) in a way that you can get through data at a quicker pace and pay attention to the louder events. My screen for looking at earthquake and volcanic activity encompassed 15 or 20 minutes of data in one screen and scrolled fairly quickly. For quieter sounds, like some marine mammals, and especially fish, you are looking at about 1 minute of data per screen and the going is a lot slower!
We have scientists who have developed software to help automatically detect certain sounds in the data we collect. This doesn’t work for every type of sound and has varying degrees of accuracy, depending on other sounds present that may be in the same frequency range. Next up, I’ll be learning about one of these programs called Ishmael (developed by Dr. David Mellinger – he’s on our People Page) and, with the help of Sara Heimlich (also on our People Page), seeing if it can do a good job picking out orca sounds right off of South Beach here in Newport. I have found many of these orca sounds manually, but at 1 minute of data per screen, it would be very time consuming to go through all of the data that way. Check back later, and I’ll let you know how the automatic detection software does.
Noise in the ocean has become a hot topic lately in the media. (It’s incredible just how loud ship noise can be. Even louder: icebergs grounding and calving). How does man-made and other noise in the ocean affect fish, or marine mammals who depend on sound to navigate, hunt, find food, or communicate? These are questions scientists are busy trying to answer. VIBES, our new group acronym, stands for Volcanic, Ice, Biological, and Earthquake Sounds in the ocean. We also record surf and man-made sounds like oil drilling, ship noise, wave energy technology, and anything else you can think of down there.
Following are some examples of what I see in the data we get back from our under ocean recordings and the sounds that accompany them. Please let me know your best guess for the final sound!
(Note: sound clips for most of these encompass the data between the 2 fine white lines shown on the spectrograms, and are best heard on decent speakers or through headphones.)
Earthquakes in the Lau Basin Orcas off South Beach in Newport, OregonOrcas and Ship Noise off South Beach in Newport, ORVolcanic Tremor in the Lau BasinSeismic Air Gun Shooting for imaging purposes in the Lau BasinBrydes Whale in the Lau Basin?
Marine Science Day is almost upon us! Come by this Saturday from 10 to 4 to see some of the scientists from our Acoustics group in the library foyer at Hatfield Marine Science Center south of the Yaquina Bay bridge in Newport.
Hatfield Marine Science Center from the air
We’ll have a PowerPoint presentation running with pictures and details about our work, a quality speaker so you can really experience some of our under ocean sounds, a hydrophone (under water microphone) to inspect, a 3-D Printer job going to check out (so cool!), a chance to see your voice on a spectrogram, and scientists there waiting for your questions. Along with all of the other groups of scientists from the Hatfield Marine Science Center campus, food available for purchase, and exhibits highlighting HMSC’s 50 years of research, this Saturday promises to be a great time. Here are some more details:
Marine Science Day at the OSU Hatfield Marine Science Center in Newport, Oregon
Saturday, April 11, 10am-4pm
Join the OSU Hatfield Marine Science Center (HMSC) in Newport for Marine Science Day. HMSC will open its doors for a behind-the-scenes peek at the cutting-edge research, education and outreach in marine sciences that makes this marine laboratory unique. Meet researchers from Oregon State University and six government agency partners. Explore with interactive science displays presented by marine scientists and special family-friendly activities by Oregon Sea Grant, the Oregon Coast Aquarium and US Fish and Wildlife. This year will feature special exhibits highlighting HMSC’s 50 years of research, education and outreach in marine sciences. Don’t miss it!
Come learn what’s new on the Oregon Coast’s most dynamic marine science campus.
For more information and Schedule of Events, see Marine Science Day
For accommodation requests related to a disability or other questions, email maryann.bozza@oregonstate.edu or call 541-867-0234.
Note: Most Marine Science Day exhibits and activities will be indoors, although visitors are advised to dress for the weather as some exhibits will be outdoors. The OSU Hatfield Marine Science Center is located at 2030 SE Marine Science Drive in Newport, Oregon.
