Alvin Dive 4599 -- Transcript -- Port Side Observer -- Scott White
15:27 x14976 y9167: Coming in view of the bottom. Pillows lightly dusted with
sediment. About 2 m, fairly large, flowing downhill toward us from the south.
Accumulation in pockets. Glass on the pillows. No life around except for
sponges. Pillows are looking like lobates.
15:33 stopped to sample, sample 1.
15:37 x14978 y9145: Starting to sample at the landing point. Sampling a piece of
fractured ("busted up") pillow. Going in all the way forward in the basket.
15:43 x14923 y9155 depth 2753: Just passed over some sheet flow in a little
depression between two mounds. A lot of talus on these. Broken up lobate, is
what it looks like. Just came up over a little lava rise with a sheet flow below it.
Still heading about 275 toward El Dragon mounds.
15:45 x14890 y9166: Nothing here is in place. All still rubble. Broken pillows or lobate.
Blocks are 0.1-1m.
15:53 x14759 y9276 depth 2778: Coming out of rubble into intact pillows. Pillows are
1-2 m diameter. Lots of buds. Sediments accumulating in a lot of pockets.
15:57 x14730 y 9320: Headed toward wpt 3. In pillows, lots of buds, sediment
accumulation in pockets. Pillows mostl piled up. Not a lot of downslope flow. Still
pretty heavy sediment.
16:00 x14717 y9344: Going over a slight dropoff. It comes back up the other side, is a
pillow wall. I'm not seeing anything broken in the pillow wall. It's all pillows. This
is very fissured up. 1-2 m wide fissures, they are deeper than I can see. It's
pillows all the way down, it doesn't look like they are broken too much.
16:03 x14699 y9379: Sample 2, putting in basket into 4a. Got a round side, comes
down with a funky end on it. About 20 cm. There's a really cool jellyfish thing out
there.
16:07 x14691 y9397 depth 2357: Getting underway to contour around the north mound
on "El Dragon" still seeing pillows. Nothing indicative of recent eruptions in this
area.
16:12 x14728 y9466: Coming around the side of one of the north mounds on El Dragon
complex, still pillows even though the bottom is dropping off. it's almost vertical
but the slope is all constuctional pillows, probably 2m size lots of buds. Not sure
how glassy they really are.
16:18 x14842 y 9490 depth 2754: Sample 3 from a budded pillow on the north side of
El Dragon, south of the fissured northern spur.
16:24 x14892 y9501 depth 2759: Heading at about 075 toward wpt 5 which is in the
lava channel. Right now a little high in the water because we are coming off the
mound complex [El Dragon].
16:26 x14947 y9512 depth 2778: Coming down in sight of bottom again. pillows and
lobes a lot of sediment here. consistent dusting over everything here. heavy
accumulation in pockets. flying toward wpt 5. these are lobate lava flows with
some pillows on top
16:30 x15048 y9533 depth 2780: Going through some pillows here. Moved out of
lobates and back into pillows. Goes back and forth in this area of the lava plain
between [El Dragon] and frijoles.
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16:35 x15203 y9550: Some sheet flows. Crossing over a big crack and a lot of talus.
Seeing a short vertical wall on my side. Coming up on top it, all folded sheets.
Folded sheets with some lobate and theres still a light sediment blanket over
everything.
16:38 x15261 y9568: Stopping to sample lobates on the upper part of the lava plain.
Trying to sample lobates and there's a lot of slit trying to build up around the
submarine. Got a little piece of lobate crust maybe 10 cm long.
16:45 x15323 y9593 depth 2783: underway again toward the small mound on the upper
part of the small scarp. Lobate terrain again. Should be just about there [the
mound]. Lobates have turned into pillows. So the little scarp is right in front of us.
We have to come up the wall. I think we're a little off on that map (scarp is shifted
to the south of Alvin position). Coming up the wall now. It's mostly pillows, maybe
some massive lobates in the wall too.
16:52 x15414 y9638: On the little mound. We're going to come in and try to sample
some of this. Pretty standard pillows, bulbous, striations. A lot of sed
accumulation in pockets and a light dusting over everything.
16:55 x15409 y9634 depth 2773: Sample 5. Pillow toe from the little mound on the
north of the scarp separating upper and lower flows.
17:00 x15299 y9689 depth 2776: Headed across this plain. Getting close to this
channel. Turned from lobates into pillows. Pillows are a little runny looking.
Fissure in the camera <1m wide, hdg 300 and fissure is parallel to us. Heavy
sediment in pockets, light dusting over everything. Still heading over fissure
which is getting wider here. This smaller depression, looks like a lava channel is
probably just older seafloor. Not clear that this is any sort of channel. Lots of
pillows and some fairly deep fissures running NW-SE.
17:11 x15259 y9872 depth 2773: Going up the other side of fissure and climbing up
wall. Lots of pillow dribs and entrails going down. Not seeing much else besides
pillows, not much decornation on them. Got up to the same latitude as wpt 7, on
west side of mound.
17:20 x15265 y9913 depth 2765: Sample 6 it's a big chunk of pillow.
17:26 x15369 y9865 depth 2741: going at hding 090 across the large mound at northern
end of dive area. Very large fissure running E-W through mound. Looking at wall,
Bunch of pillows and massive lobate flows in the wall. Below us is pillow, lightly
sedimented, but broken up and out of place consistent with a lot of tectonic
activity through here. Big rounded pillows exposed in the wall.
17:33 x15570 y9861 depth 2740: little ways off the bottom.
17:37 x15604 y9891: stop and settle down to grab a sample. try to grab this lobate
sample now.
17:39 x15602 y9902: there is a crack, 0.5m wide headed 060. Stopping to sample.
17:41 x15609 y9903: heading is 080 and parallel to the fissure
17:45 x15594 y9893 depth 2770: underway after sampling 7. big piece of pillow/lobate
transitional flow. from east of set of mounds on northern end of lava plateau
17:51 x15655 y9746 depth 2772: stopping to sample some sheet flow we just stopped
over. lots of chaotic, folded sheet flow. broken up on the top
17:57 x15687 y9714: finished stopping to sample 8 from a folded sheet flow in this
channel. continuing SE. following along direction of channel flow. flat and lobate
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here with sediment blanket, starting to coalesce.
18:00 x15762 y9662: just entered another area of folded sheet flow.
18:02 x15781 y9608 depth 2774: heading across this sheet flow area. dropped off a bit
on us. headed south to try to find the contact. I think the upper area are sheet
flow and lower are lobate.
18:05 x15789 y9542 depth 2783: lobates with big flat surfaces and some inflation
cracks in them. little collapses a few 10's cm wide. others are a bit larger.
18:11 x15892 y9526 depth 2780: heading 070 parallel to a big fissure, walls are mostly
lobate flows. sediment cover is thin but uniform across everything. bulbous
lobates. numerous inflation cracks
18:17 x16090 y9621 depth 2774: crossing lobates and pillows. sediments pretty heavy.
coalesced in pockets. blankets with just some outcrop showing.
18:24 x16214 y9693 depth 2775: going through collapse lobates with bathtub rings and
some are bigger than sub. about 1m deep.
18:28 x16213 y9690: sample 9 from lobate at the edge of a collapse here.
18:31 x16262 y9674 depth 2774: heading over lobates to pillow, most are pillow flow
now. traversing along south rim of pillow mound structure. pretty consistent with
what we have seen so far.
18:40 x16481 y9776 depth 2777: going across contact from older lobate to pretty old
sheet flow unit. sheet is broken on top, folds and broken folds. just crossing over
the bathymetric contour
18:43 x16549 y9813 depth 2775: climbing up wall made out of mixture of broken pillows
and lobates. bathy map nav is probably a little off to the south. wall shows up as
contour set not quite where we are. top of wall is lobates, base of wall is lobates
but also some sheets.
18:56 x16649 y9886 depth 2775: sample 10 comes from small mound at north end of
high lava plateau
19:09 x16630 y9891 depth 2773: after sampling at mound we're heaaded south along
channel coming from mound. so far we're coming out of pillows, getting flatter
and lobate-like. these pillows are pretty big, mostly close to 2m and very
coalescent. sed cover pretty high, coating most of the surface and in pockets.
19:10 x166090 y9851: fissure runs running about 250-260 deg azimuth
19:13 x16580 y9815: edge of big drop-off. drops down to the south. I can see bottom
still. it's pretty faint. drop of 15 m.
19:17 x16601 y9723: headed south along what looks like a channel but it's got pillows in
bottom. they are fairly old.
19:18 x16600 y9770 depth 2776: coming out of high lava plain area. seafloor not
changed a whole lot, but probably more lobates here.
19:21 x16602 y9646 depth 2774: over big flat area. a lot of sediment on this, folds or
maybe lobes. probably lobes, some smaller collapses in the lobates and sheet
flows. didn't come from that channel we were in. this is a different unit
19:27 x16550 y9531 depth 2774: crossed over 1 m tectonic fissure, and the azimuth of
that was about 100 deg.
19:29 x16529 y9488 heavy sediment and lobate. zone of little fissures running E-W to
NE-SW. area big inflated lava plain, some units of pillows but almost all lobates,
sediment coating
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19:48 x16461 y9372: sample 11 lobate crust at southern end of big channel feature
19:54 x16463 y9339 depth 2779: driving south until we get low on power, trying to
connect John's transect on 4598. lobates with a little bit of sediment
19:57 x16484 y9260 depth 2778: looking down into big collapse, with some sheet flow
down into it from north side. south side rubble and talus. big wall. really big slab
of lava. that is a great lava tube. turn all the way around. looks like a tunnel, the
slab is a big arch, maybe 3-4 m wide. did you see it? that's not a small feature.
20:03 x16498 y9258: sitting inside of big collapse >10 m wide. impressive lava tube
and arches of lobate. getting a lot of pictures of this.
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