During the expedition, we invited the public to send questions to the team at sea; questions and replies are posted here.
The Okeanos Explorer Survey/Mapping Team produces Digital Elevation Models from the data being acquired from Deep Discoverer (D2) after each dive. It is interesting to watch the team create these amazing models on the video stream. It appears that the Seafloor Information System and HYPACK Survey programs are being used for other mapping/imaging work. Is the team using another type of topographic mapping software tool to create digital elevation models (DEMs)? If so, what is the name of the software used to produce the DEMs?
Question from: Jim
The remotely operated vehicle D2 is not currently equipped with sonar to collect data to create DEMs. The scanning sonars on D2 and Seirios are used for situational awareness for the pilots, but the data is not collected.
The Mapping Department uses SIS to collect bathymetric and water column data with our Kongsberg EM 302 multibeam sonar. Bathymetric data is processed using CARIS, and is visualized in Fledermaus. Hypack is used for making line plans to inform the ship where we would like to go to collect data.
Answer from: Meme Lobecker, Physical Scientist, NOAA Office of Ocean Exploration and Research
Can these be "dated" in part by the amount of sediment building up on one side or another, or are they creating their own edges by pushing up and falling back? Is it possible that the fractures in the sea floor through which these extrusions are appearing could have been caused in part by the massive asteroid that hit near the Yucatan (blamed for the mass extinction), or are there regular tectonic events that might open up a fissure?
Question from: Craig
Yes, if we could get samples of the asphalt, we could date these features. The soft sediment build up here could happen relatively quickly on a geologic scale. We can, however, use the biology that has colonized these features to help give us an age estimate–most likely they are on the order of tens or hundreds of years old.
These "tar lilies" are caused by regular tectonic events, not an asteroid. The big pile of sediment in the Gulf of Mexico is always on the move by the salt and the associate hydrocarbons that lie under the sea floor here. There are a number of really interesting features that are caused throughout the Gulf by movements of hydrocarbons and salt. The asteroid you are talking about was 66 milliion years ago, and in my mind, these really are two distinctly separate geologic events.
Answer from: Jamie Austin, Science Team Co-lead, NOAA Ship Okeanos Explorer
Do we know for certain that these "tar lilies" still actively "blooming" with new asphalt although there are no bubbles or materials coming from the surface? I do notice some kind of white coating in the center of the bloom.
Question from: Jason
We do think these are still active. The white coating is evidence of bacteria using hydrocarbons that are leaking from the seafloor. Although we aren't seeing bubbles or oil drops, we saw chemosynthetic worms which is evidence of an active site. Also remember that rates of geologic movements are extremely slow and periodic, so although we may not see it right now, they most likely are still active. Chemosynthetic animals present indicates that microbes are chewing at the asphalt...not that the asphalt is still flowing. With this much carbon, the microbes will be busy for many centuries. The microbes make the sulfide needed for chemosynthesis.
Answer from: Jamie Austin, Science Team Co-lead, NOAA Ship Okeanos Explorer
I have circled the creatures I am curious about, if they even are creatures. Just wanted to know what they were as the crew didn't mention them by name. This is all so interesting!! Was expecting a shipwreck but this is pretty mind-blowing!
Question from: DD
Both are anemone, the first we aren't sure of the exact identification, but they are common at brine pools and seeps. The second is a fly trap anemone.
Answer from: Stephanie Farrington, Science Team Co-lead, NOAA Ship Okeanos Explorer
Regarding the tar flowers, could these be a result of oil drill testing?
Question from: DD
They are the reason for oil drilling. These are evidence that there are asphalts or hydrocarbons below the surface. It is unlikely that these are due to exploratory wells. Such holes usually have some hardware left at the seafloor. We have seen none of that. Nor have we seen any of the cuttings on the seafloor that drilling leaves.
Answer from: Bob Carney, Professor, Department of Oceanography and Coastal Sciences, Louisiana State University and Jamie Austin, Science Team Co-lead, NOAA Ship Okeanos Explorer
How would all of you biologists, geologists, and robot operators rate this amazing exploration?
It's amazing – I've never seen anything like this, I've read about similar phenomena, but this is incredible.
This is a great advertisement for telepresence since we had the expertise available to quickly switch from shipwreck mode to geology mode.
This is phenomenal - this is in ways more special than the shipwreck we had planned on seeing. This is the first discovery of massive asphalt extrusions in the Gulf of Mexico. It's just amazing!
This is fascinating to see the biology take advantage of this giant tar structure. We have seen this other places, and this is just one more example of the biology taking advantage of the diversity of habitats in the Gulf.
After many ALVIN, Johnson SeaLink, JASON, and other dives in the Gulf, I have seen little new. The exploration, however, does increase the awareness of the public and the scientific community as to how fascinating the Gulf is.
Answer from: Several team members
How do large boats like the Okeanos handle extreme weather at sea? I was curious considering the cancelled dive on Tuesday.
Question from: Melissa
At sea sometimes heavy weather is unavoidable, so larger ships like the Okeanos Explorerconduct different types of operations depending on the sea state or have to wait out the rough seas. On Tuesday (4/15), the Okeanos Explorer was able to collect some multibeam mapping data despite the rough weather, but because of 10-12-foot waves, the ROV could not safely be deployed or recovered. Therefore the dive was cancelled. Most often during heavy weather, large ships try to find a comfortable ride (a route over the ocean with the least amount of big rolls and heavy pitching) and have to wait for the storm or weather to pass.
Answer from: LT Emily Rose, Operations Officer, NOAA Ship Okeanos Explorer
Is anything known about the ship that was explored at the bottom of the sea on April 17? I just heard someone say that it might have been a privateer, given the extent to which it was armed? Further, someone earlier in the day mentioned that it was assumed that all lives were lost (I believe in reference to the fact that the very expensive chronometer didn't make it off the ship). To that end, why are there no skeletal remains in view?
Question from: Amanda
The amount and type of arms on Monterrey A, visited on Thursday, would support the privateer theory. It was well armed with cannon, muskets, and swords, but the arms were a mixed variety, not of uniform manufacture and type. They came from multiple sources and probably several counties. The military generally preferred use the same kind of arms among their forces for ease of maintenance and repair, and it also made it easier for the soldiers or sailors to learn how to operate and maintain one particular type of arms whether a musket or cannon. It also kept costs down. Remains, including bone, are generally consumed by marine organisms. Bone is sometimes found buried in sediment.
Answer from: Frank Cantelas, NOAA Office of Ocean Exploration and Research
Any chance of spotting an oarfish trundling by?
Question from: Craig, via NOAA Office of Ocean Exploration and Research Blog
Yes, it is possible. We have seen three or four oarfish upon vehicle recovery, but at our operating depth it would be rare to see one during the dive.
Answer from: ROV Pilots
I'm interested in the jellyfish that was caught on camera at around 16:35 Eastern time. I believe Ctenophore was mentioned. Would you be able to tell me what type it was?
Question from: Paul
This one has stumped our science team. We know that this is a yellow ctenophore, a first for some of our scientists, but we haven’t been able to identify which species it is. We have sent the pictures over to an expert at the Smithsonian who hopefully will be able to help us figure out what this is.
Answer from: Kasey Cantwell, NOAA Office of Ocean Exploration and Research
At 2:58pm EST, you were focusing on something with 10 legs, and then the camera and ship began to move to the right...but at the very top of the screen before the move, I swear I saw the tail of...something?...rather large undulating as its owner was swimming off the top of the screen. Any idea what that was?
Question from: Katie via Facebook
Around that time we saw a very large rattail that was checking out the vehicle. That could very well have been what you saw. The best view of the rattail came from Seirios as it swam around D2, but it is possible that we may have gotten a glimpse of its tail from D2.
Answer from: Kasey Cantwell, NOAA Office of Ocean Exploration and Research
Are you seeing signs of the oil spill accident still in the area you are researching?
Question from: Ina Sue
From the hundreds of observations near the spill, impacts to benthic biota were restricted to ~ 20 kilometers away from the well in deep water. The area we are exploring with the Okeanos Explorer right now was not affected by the spill at all. All of the seepage we've been seeing is natural.
We did find corals that had been killed by the spill around seven miles to the southwest of the well (White, et al, PNAS, 2012) and we are about to publish on three other sites we subsequently found closer to the well.
Answer from: William W. (Bill) Shedd, Senior Geophysicist, Bureau of Ocean Energy Management
Can you please explain the screens that we see on Stream One and what each of them means? It all looks really cool!
Question from: Jordan, NZ
If you scroll down to the bottom of the live video web page, you will find a very brief description of what you might see on each screen. What is being shown on the video stream screens may change depending on the exploration and operations at hand, but generally, here is what is happening on different screens at different times:
When the remotely operated vehicle (ROV) is not in the water, you will sometimes see scientists and mapping technicians working in the control room onboard the ship. The mapping technicians work in shifts through the night, managing the data including that coming from the multibeam sonar system.
When the ROV is in the water during the day, you will see the video and hear the scientists both on the ship and at Exploration Command Centers around the world communicating with one another about what they are exploring. EXCITING STUFF!!
One frame sometimes shows the video from Seirios, the camera sled that travels tethered just above the Deep Discoverer ROV. This sled has high-definition cameras and special lights to take great video and images of the ROV in action.
When the multibeam sonar system is mapping the seafloor, you will see what the mapping technicians are seeing. The colorful fan-shaped image is the result of transducers sending over 288 beams down to the seafloor at one time and creating a swath of depth measurements that is over five times as wide as the depth under the ship. So, for example if the ship is traveling over water that is one mile deep, the swath could be five miles wide! For more information on sonar and how it works, visit http://oceanexplorer.noaa.gov/technology/tools/sonar/sonar.html
Sometimes you will also see cameras from various parts of the ship, like the fantail (back end of the ship), where the ROV is deployed. Other times you will see one screen broken into small views of several places on the ship.
Answer from: Susan Haynes, Education Program Manager, NOAA Office of Ocean Exploration and Research
I’m so glad you are broadcasting again from one of the most common environments on the earth surface but one of the most rarely seen. Thank you for making live broadcasts from the deeper ocean into public broadcasts.
I missed the live broadcast from the 11th and 12th. Was the black pool in this image a petrochemical seep or possibly a drill leak? Thanks for any info on it.
Question from: Ed, Florida
The image you provided is actually of a brine pool that we discovered on April 13th. On Dive 02 of the 2014 Gulf of Mexico Expedition, ROV Deep Discoverer found an interesting brine pool. Brine seeps are common in the Gulf of Mexico, but brine pools of this size are not common (up to 10 meters wide and ~100 meters long). They are caused by seepage from salt bodies below the surface sediments and often are associated with hydrocarbon seeps. Around the shores of this brine pool we found anemones, fish, corals, sea stars, crustaceans, and tube worms. For a description of our first two dives, check out the Mission Log from Kody Kramer from the Bureau of Ocean Energy Management.
Answer from: William W. (Bill) Shedd, Senior Geophysicist, Bureau of Ocean Energy Management
Yesterday you all commented that there was a lack of crabs and fish at the depths of 900 meters(?). Is it common for there to be an abundance of fish and crabs at that depth?
Question from: Facebook user
The distribution of most bottom-dwelling (benthic) invertebrates (i.e., crabs) or fishes is usually associated with some type of hard substrate. This hard substrate could include deep-sea coral reefs (e.g., Lophelia - which we’ll see the last week of the expedition), shipwrecks (planned for later this week), hydrothermal vents, mussel mounds like we saw the last day or so, and even oil rigs. These hard substrates provide fishes, corals, crabs, and many other invertebrates protective habitat. Red and golden crabs (seen on Dives 1 and 2) will walk rather far from substrate, but as you saw on Dive 1 are also associated with rock outcrops in this area.
I did find it interesting that there were a few places that had large rock outcrops and the animals seemed to all concentrate right around the cold seeps (where the bubbles were). The mussels, white crabs, and shrimp we saw on Dives 1 and 2 are what we call chemosynthetic organisms or are associated with chemosynthetic organisms. Chemosynthetic means that the organism uses chemicals (methane and hydrogen sulfide in this case) to make food instead of using sunlight (photosynthetic) like plants.
The bacterial mats (white, black and orange crusting on the bottom) are chemosynthetic bacteria living on the methane seeping out of the substrate. The mussels we saw actually have the chemosynthetic bacteria living within their tissue, converting these chemicals into food for the mussels. Some of the other organisms feed directly on the bacteria. You can find out more about chemosynthesis here http://oceanexplorer.noaa.gov/facts/photochemo.html.
Answer from: Stephanie Farrington, Biological Co-Science Lead, NOAA Ship Okeanos Explorer
