Dive 2927 High Rise
Transcript: J. Baross
pilot: Pat Hickey
port: Veronque Robigou
starb: John Baross
Bottom 9:15 am: bottom mostly sediments; two spider crabs
9:25am: two inactive sulfide structures approximately 2 meters high, some small fragments of collapsed sulfide; accumulated sediments on basalt approximately 2 cm. Sponges are everywhere.
9:29am: At the top of a major wall that is estimated to be approximately 12 m high. Working way down the ledge of the wall. No sulfides are seen. A large (15 cm long) white halothurian is hanging out on the ledge (the first halothurian I have observed)
9:32am: At bottom again - mostly relatively thick sediment layer with many mounds and pits indicative of bioturbation by deposit feeders
9:34am: small sulfide structure; mix of a thin layer of sediments and areas of talus; can see another wall off to the right
935am: 4973, 6104, driving away from sediment and see more talus and basalt
9:40am 6850, the wall is probably higher than 10m and we are descendng the wall
9:43am: climbing another wall; see clusters of brittle stars on one rock but nowhere else (20 to 30 brittle stars clustering on one side of a rock)
9:45am: approaching a steep wall and can see some spires. Large sponges dispersed on the basalt; also see one large rat-tail fish; starting to descend the wall
9:50am: observe isolated diffuse patches with tube worms; most of these patches are no more than 2 or 3 meters in diameter. Extensive orange and yellow sulfide deposits and metal oxides on the basalt. Extensive talus fields. Move into another area with extensive metaliferous sediments, tube worms, spider crabs. Climb up wall and see increase in metalliferous sediments and tube worm patches, spider crabs hanging around the tube worm patches. Can see sulfur and metal deposits in the sediments. Moving away from this area and less metaliferous sediments and no tube worms.
9:58am: clusters of tube worms covered with microbial mats and some evidence of diffuse flow. Patchs of tube worms are somewhat isolated from sulfide structures. See also evidence of tube worm patches where I cannot see evidence of diffuse flow. Many of the tube worms are lying down and appear to be dead?
10:01am: we are climbing a large sulfide structure with flanges with ovrhanging tubeworms. Flange approximately 5 meters long covered with smokers and appear to have clear fluid flow out of 6 smokers. To my right there are 7 ot 8 flanges and extensive diffuse flow. Thick flanges have more tube worms and they are larger than flanges that are thin or have significant flow of hot fluids over their lips.
10:05am: moving away from flanges and move up wall of large sulfide structure with tube worms, gastropods, and much metaliferous sediment deposits around the base of the structure.
10:08am: We are on the west side of Godzilla and climbing up the structure. There are hundreds of flanges of different sizes, mostly very small (less than 1 meter) and do not extend out from the main structure more than tens of cm. No evidence of pools under these flanges. At 10:09 we are 24 m off the bottom and climbing Godzilla.
10:10am: We are 40 m off the bottom and still climbing godzilla
10:11am: more than 40 m from botttom and see smoke. Now see 6 huge flange structures some of which are 2 to 3 meters long. Diffuse flow around and through these structures is extensive. Again, flanges with white lips and much diffuse flow at the edges are not colonized by tube worms and appear to have only extensive microbial mats. Thick edged flanges with little diffuse flow over the lips are colonized extensively by tubeworms. Spatial distribution of animals on flanges depends on degree of flow over lips and thickness of flange. Flanges with thin lips and extensive diffuse flow have thick microbial mats and no or few animals.
10:21am: Smoker at 5776, 8329 measured at 344¡C; sampled smoker at 10:22 am using a descrete bottle (far right), first gas tight did not look good according to Pat and a second gas tight was filled (yellow 5). Marker 1T deployed 1 m to the right of the smoker sampled.
10:43am: sampled a second smoker close to the first. High temperature was 341.2¡C. Filled major 12 and gas tight red. Deployed marker AJ. The tip of the smoker sampled was broken-off and put into the biobox. Sampling completed at 11:00am.
11:09am: Pass Bambi on way to Broadwalk. See a very nice flange.
11:13am: Between Bambi and Broadwalk see lots of healthy tube worm fields. Extensive diffuse flow areas, microbial mats, metaliferous sediments, and large tube worms. Approach a large flange with some large tube worms on top.
11:16am: We see marker C on Broadwalk. Marker is heavily colonized with microbial mats (Beggiatoa spp) and animals. Can see evidence of extensive diffuse flow around marker C.
11:20am: Many flanges with extensive tube worms and diffuse flow. Lips of flanges free of animals. Good site for sulfide worms. Thick microbial mats and much diffuse flow through flanges. Can see a smoker to my left.
11:22am: Site marker D on Broadwalk. Excavate smoker and make hole the size of Grand Canyon (about a 10 inch hole). Temperature is 342.2¡C, marker A8. Get water with Major 3 (red handle) and gas tight, purple 7.
11:51am: locate a small flange on Broadwalk that could drop into the basket. Coordinates 5753, 8289. The flange is approximately 2 ft wide and 4 inches thick and weighs approximatly 35 lbs. Temperature of flange pool was 234 to 238¡C. Flange was dropped into the basket at 11:57:51am. Took video of flange structure after sampling for future visits to observe how this flange grows and develops.
!2:06pm: observe new mound site having one of the most extensive and thick microbial mat and tons and tons of tube worms. The microbial mats are primarily yellow and white.
12:11pm: Get to Ventnor. Giant spires and smokers. Tube worms and some sulfide deposits on tube worms.
12:12:22pm (5616, 8224) see clusters of 3 smokers and a single smoker. This marker at this site was apparantly buried. It is apparent that these markers get colonized by microbes and tubeworms and the markers fall under the weight of the colonized biota. Flange on Ventnor has an extroadinarily extensive and healthy tube worm community. The tube worm tubes are white and very clean and not extensively colonized like the tube worm tubes at Godzilla.
12:20:53am: Prepare to sample Ventnor smoker with the last descrete water bottle (smker at 5612, 8228). Water temperature at 341.7¡C. Smoker sampled at 12:25:12 using yellow descrete No. 6. Marker AI left near tube worm patch.
12:42pm: Flange at 5607, 8221. Flange pool water is 303.3¡C. Leave marker 1M at top of Ventnor.
1:02pm: Back to Broadwalk and looking for pool that can be sampled. Pool temperature is 324.1¡C. Water sampled with manifold. Marker AL left at flange site (5748, 8298) and sampling completed at 1:26pm.
1:31:19pm: Niskins at 5, 10 and 15 m over Broadwalk (5756, 8298)
1:31pm: end of dive
John A. Baross