- Okay. I am ready when you are.
- Hey, so I'm Erin.
- Hey Erin.
Everyone, I'm Maddy.
And we're actually just transiting back
from Johnson Atoll to Honolulu.
- Yeah, probably about 400 nautical miles or so
from Honolulu right now.
And yeah, and headed back after 20 plus days
out in the Pacific
- That's right.
We're just coming back from the Johnston Atoll unit.
It's one of the most remote regions in the entire planet.
And it's actually the work that we've just been doing
is gonna be used to inform our next ROV dive.
- Yeah, that's right.
So we have been focusing on sea floor mapping
and we are sea floor mapping for a lot of reasons
but one of the primary reasons is so that we are ready
on the next expedition to get those ROVs
in the water as quickly as possible.
- Absolutely. And many of the targets that we've actually
dove on on this in these last three weeks are those
that we are probably gonna bring the ROVs in.
And Erin, you have best the best eyes on those, right?
- Well, me and the entire mapping team,
'cause they've all been staring at them a lot every day
and helping to build up these coverage maps and yeah,
really get us ready to go so
that they can hit the ground running.
- Should we take a look at the data?
- Yeah.
- And get a better idea.
- Let's take a look.
So we're looking at a data in Fledermaus
which is a software we like to use for visualizing
our ocean mapping data.
And I'm kind of starting here in Oahu
and I'm just gonna zoom out to say that
as our base maps, we do have what looks like a map
of the ocean but this is just satellite altimetry
which you might have heard us talk about before.
And that's just an estimate of what the sea floor
looks like.
And sometimes it's pretty good,
and sometimes it's not great at all.
So we try to do some mapping to improve that situation.
And so this is just the kind of generic overview
but I'm gonna bring us in and show our data now.
So I'll turn on our coverage
from our mapping and you can see, we started mapping.
If we're looking at the bright line there.
We started mapping just off of Oahu.
As soon as we're on areas where there's no coverage
by high resolution systems, we turn on our sonars
and we try to build up our data set
both for where we're planning to work like Johnston
which is here, but also in international waters
and around Hawaii as well.
So always constantly trying to help build
this continuous map of the sea floor
because the data really is so sparse
and any little bit that we can contribute
does help the the bigger picture
and the global map of the sea floor.
So I'll zoom us in.
Bring us into 3D so we could take a look at this.
So we spent about three days transiting from Honolulu
to the Johnston units of the Pacific remote islands
national monument.
And so the circle that we're looking at here is
the Johnson Atoll EEZ.
And it's also the limits of the monument too
so that they coincide with each other.
And that is 200 nautical miles from Johnson Atoll
at the center.
So quite a really large area that's covered
by this national monument.
We came in.
I'll do north oriented first
just to give us some perspective.
So that's about oriented to the north.
We came in on the lower Southern,
Eastern side of the Atoll on the Southern side.
And we did that very specifically.
So the mapping was planned by Lindsay
who is our mapping coordinator.
He planned this transit and then Hannah
is coming over here specifically.
So that as we transited over to our main mapping area,
we can get coverage on many of the possible targets
for NA 141.
So let's zoom in and take a look.
So we came in.
This seamount here was, is not a target
for that expedition, but we went over it
'cause it looked fun.
We always try to hit anything that looks interesting.
And if I just turn off the coverage,
this is what it looks like when there's no coverage.
So this is the satellite altimetry data.
It's very smooth.
Doesn't show you any features.
It gives us an indication that there's something there.
But then when we actually go over it
with our sonar and we start to get really nice detail
and we can see this is a guyot
or a flat top seamount that we passed over.
We continued along and mapped our way along
the edge of the easy.
And one of the first seamounts we encountered
was this one which is target three for NA 141.
And though I can't split it out now,
on our first pass we only got to go over this once.
So there was just one kind of pass over the top of it.
And we all kind of got the feeling that we wanted
to come back 'cause it was such a really large seamount.
It's massive.
We still didn't even finish it.
We did as much as we could
when we came back to hit it on our way out.
But you could see there's still quite a bit
of potential seamount to go.
We got pretty nice top of it.
And if I turn off the satellite altimetry
so you could see it really clearly,
just some really nice detail on that target three seamount.
- [Maddy] It's really such a difference, isn't it?
- [Erin] Oh, it's yeah.
I mean, sometimes you could be like, eh, you know
with smaller features they didn't really add much.
It adds a lot, right?
A lot of detail and the kind of detail
that the scientists want to be able to plan their dives.
They like to target ridges typically
and the features with a lot of topographic difference
so that things can hold onto it.
So this kind of map will let them make their dive plans
much more easily without a lot of guessing
with set better indication.
So after target three, we continued up
and hit this target, which is number two.
I will now turn on a little bit of background altimetry.
So the reason it looks like there
is a gap in the top of that one
is because this seamount was partially mapped already.
So that was the data that did exist.
And I believe that was the Nautilus pass
which is pretty cool.
We did that a few years ago
but we wanted to try and get the sides of it as well
in preparation for dive planning.
So if I turn our coverage back on
and turn that one off,
you could see we got nearly complete coverage
on that seamount number two,
and so totally ready for the next expedition.
Continuing on, we passed over target six
another pretty cool seamount.
And if I turn on the base map for that one,
turn on the GMRT.
Again, completely unmapped.
Nothing there to see, just a gentle bump
in the satellite altimetry, but
with the multibeam sonar getting really nice detail.
The multiple kind of star shaped ridges that you get
on some of these seamounts
and just really, really great detail.
We continued up and all of this took
this kind of gentle move to our main area,
took a couple of days.
We just kind of progressed over there.
This is a huge area.
And that's part of the thing that
part of what people may not understand
how gigantic these areas are.
We would, some of these lines we'd be driving
in one direction for 10 hours
or 15 hours without any change in direction.
And all of that was still happening within the monument.
I just think that's amazing.
- [Maddy] Right.
And when we say seamount,
we're really saying underwater mountain
- [Erin] Yes, exactly.
- [Maddy] Huge features.
- [Erin] Huge, huge features.
Yeah. These are rising 4,000, 3,000 meters
off the sea floor.
And just, yeah, gigantic just like a mountain
that you'd picture if you're driving around Hawaii
or anywhere else.
So continuing on.
Crossover the ridge, this is target seven.
Another potential seamount that they were thinking
of diving on and continuing on.
And, you know, always catching little bits
every now and then.
So here we didn't have enough time to spend time here
but you can see even in the lower interest areas,
we always have our sonar because there's no data there.
And there's always some interesting little bit
that tells you a little bit more of the story
about what's happening on the sea floor.
And then continuing on.
Got up here.
This was later but we spent actually quite a few days
just doing some gap filling mapping.
So in addition to working towards NA 141 goals
of hitting these targets, we are also tasked by
our partners and sponsors at the Noah Office
of Exploration to fill in gaps in coverage, right?
And so there was a pretty massive gap here
if I turn off the coverage.
People had nicely mapped these seamounts.
Actually this group of seamounts were mapped by John Smith
who's on the ship with us on this expedition.
He did those on the Falcor, but there was all
this kind of area around it that was not mapped.
So we took the time to go and fill that in.
And there was a lot of flat (laughs).
If we remember it a long time ago,
but we had a few days of some really flat abyssal plain
kind of terrain but then we got some nice surprises
like these little features here.
I turn off the GMRT.
These cool little kind of small
but still pretty massive bumps on the sea floor
and added some additional coverage to the seamounts as well.
So always building up that coverage
and filling any gap where we can.
This was to get us up over a gap as was this.
From there we went, I don't know to, oh, one more seamount.
We'll talk about that one.
This is... Which target is?
I can't read it.
That is target 10.
So another potential seamount that is planned for NA 141.
And then onto my favorite, this ridge feature.
So this was pretty cool from a geologic perspective
and also of interest for NA 141.
And what's interesting about this.
Well, the orientation is interesting for one.
It's kind of more east-west oriented.
It doesn't have that strict seamount feature.
It's more like a ridge, as I said, but just, I don't know.
Some really cool (indistinct) imagery
of just looks like the sea floor being pulled apart.
Just really liked it.
But more technically, what was important about this?
The geologic team was interested.
The scientists coming on the next cruise
were really interested to dive on this
but were unsure of any of it was actually
within ROV dive range.
So the limitation for the Hercules is 4,000 meters.
And when we were planning on where we might dive,
and then where we might map,
we could estimate where 4,000 meters was using the GMRT
or the that background map that I showed you.
And this is it's, they're not draped
but showing us kind of the overview perspective
of what showed up as being above 4,000 meters.
And based on the satellite altimetry,
this was gonna be the only place,
this tiny little spot was the only place
that would be within dive depth for the Hercules.
And then there was one little spot up there too
and that's just kind of perspective that's throwing it off.
But it was kind of maybe the very tippy top of this.
So by going and doing the diving,
if I turn those off,
you can see by the red contour,
this is now the actual 4,000 meter contour
on our multibeam data.
And you can see there's actually quite a bit of potential
here for a more extended dive and it will allow
the scientist to if they choose to come here to get samples
of rocks and things to help them really maybe nail down
why this feature is like it is,
how it fits into the geologic history.
And that was my most exciting sea floor feature
of this trip.
I just think it's the coolest.
So we call that the the ridge feature
and you can see both for dive 11 and dive 12,
some potential to actually get a dive in,
which we're pretty excited about.
And then we finished that up and then we started
moving back south.
So moving back down over any seamounts
that we crossed on the way, we added additional coverage
and then went way back down
and finished pretty much anything we could.
So I think that's kind of the overview of what we did.
You'll see these spaces, these numbers floating here.
They are also potential guyots
but either they were covered already.
So you can see dive number 13 and dive number 14
we had really good with altimetry on already
and then there were other potential dives up north
but we decided to not worry about trying to map these.
Leave those alone and really focus on what
they are calling the primary dives
which are down here in the south.
- Awesome. And one thing that, you know,
is really sort of unique about this current expedition
that we're on is everything, all of the data
that we've collected, all of this mapping information
is informing the very next cruise.
So we're sort of laying the foundation, right,
for what the next team is going to go in
and get eyes on the sea floor.