Dive R493  
      Dive Plan: Dive R493 is an extension of Dive R492, which was halted to recover the elevator. Again the objective is to map the 1998 lave flow from the caldera down to 45deg 52min North.  
       The earthquake swarms extended south to that location but the only seafloor information is from Dive R465 ('98), which mapped a lava flow at the site of the SeaBeam anomaly at 45deg 52min North.  
      Vents discovered along the way will be sampled. On Dive R492 new vents were discovered at the western edge of the contact between old and new lavas.  
      ROPOS Configuration :Suction Sampler, 5 and 7 function arms with claws, cameras, and BioBox  
      Note: Nav fixes not edited in the logs. All fixes were logged, regardless of accuracy. Use the dive plots to determine actual positions.  
  UTC Hour Min Depth (m) Sub Hdng (deg) UTM X UTM Y Comments Frmgrbs, Photos, Samples
3 30         ROPOS in water  
6 4 1052 320 422617 5083763 ROPOS is continuing to go down. Started down around O3:30 UTC  
6 35 1541 188 422747 5084862 Just above bottom. Lobate flows below.  
6 38 1543 242 421952 5084933 lobate new flow, but some larger lobes appear to be older. This may be a function of their rougher texture that collects sed. more readily. Hard to tell. Probably all older flow. Larger lobes are transitional to pillows with good striations on surface.  
6 41 1544 247 422736 5084866 good fix here in Older lavas. These all have brittle stars all over them, moderate sed between lobes and pillows.  
6 40 1545 250 421952 5084933 Older Lava West of contact, close-up of surface showing typical sessile biota including echinoids R493-1
6 44 1543 83 422745 5084867 Mix of pillows and tubular flows that appear much glassier but are also old. Rat tail fish. Photo 1 old pillows Photo 1
6 45 1544 90 422777 5084887   Photo 2
6 45 1544 82 422777 5084887 Pillow in older lava R493-2
6 46 1544 81 422777 5084887 Older pillows. west of contact Pic 3
6 47 1543 78 422793 5084897 good fix. Still in old lavas  
6 48 1543 78 422339 5085300 Brittle stars on pillows photo 4
6 53 1541 86 422789 5084891 continuing in mixed older pillows and tubular flows, lots of biology on surface, small amount of sed inter pillow. Photo 5
6 59 1540 80 422834 5084901 going east, a few bigger pillows, big fish. still in older lavas with brittle stars and sponges. Switched from local to UTC time on SIT overlay  
7 2 1540 124 422851 5084883 Contact new lava flow R493-3
7 4 1540 150 422890 5084899 New Lava R493-4
7 3 1539 154 422890 5084899 Contact between new and old. Young flow is fairly sed free very tubular and glassy, a few brittle stars, slight sed in cracks. Stopping for a sample  
7 9 1538 139 422894 5084894 Surface of young flow near the contact. Station here to get sample. R493-5
7 12 1541 139 422527 5084408 Right at contact, more massive old flows. Picture 8
7 21 1541 90 422890 5084909 Gorgonian on older flow R493-6
7 23 1541 67 422883 5084910 sample of old flow R493-7
7 34 1541 74 422882 5084905 x=42282 y=5084905 good fix. Can't sample glassy old lavas so we will take a core. Using orange core.  
7 37 1541 46 422880 5084907 grabbing at contact W5 R493-8
7 37 1541 44 422880 5084907 stbd rock core (orange)-getting ready R493-9
7 39 1541 18 422879 5084904 Taking wax core R493-10
7 38 1541 45 422880 5084907 Taking a rock core with orange corer at ContactW5. got a few pieces of old lava x=422880, y=5084908 Rck_core

_R493-1

7 48 1540 40 422880 5084907 Heading east after sampling  
7 49 1540 80 422886 5084910   photo
7 50 1540 79 422886 5084910 New lava R493-11
7 50 1540 78 422896 5084916 New lava - Beautiful lava drip feature R493-12
7 50 1540 81 422896 5084916 Drip R493-13
7 51 1540 357 422782 5084764 contact of new and old. sampling of same as drip sample Photo 15
7 52 1540 353 424147 5085837 picking up piece of rock R493-14
7 53 1540 352 422904 5084921 good fix while sampling  
7 56 1540 17 422891 5084910   R493-15
7 57 1540 11 422891 5084911 small piece of new flow put in stb. bio box x=422899 y=5084917 Rck_R493-2
7 58 1540 1 422891 5084911   R493-16
7 59 1538 96 422891 5084911 starting to head east again in young flows. Photo 16
8 0 1538 96 422928 5084938 some lobates with collapse, meter or so thick here  
8 1 1538 93 422912 5084897 back into smaller glassy tubes and lobes.  
8 5 1537 102 422912 5084872 Going back to the bottom - sheet flows, glassy, drained out area.  
8 5 1540 101 422905 5084877 Big crab and a big starfish  
8 5 1540 101 422905 5084877 Crab and sea star R493-17
8 7 1540 98 422907 5084824 Picture of young lavas, beginning to see some sediments under the lobes Photo-18
8 8 1539 102 422910 5084813 Something's up with our headings? We're stopping.  
8 10 1539 94 422935 5084879 Sediment in the bottom of the pits Photo-19
8 11 1538 89 422976 5084898 Pillow lavas and big fish Photo-20
8 11 1535 101 421318 5086936 Extensive drained out area  
8 12 1536 99 421318 5086936 Exploded pillow  
8 12 1537 94 425539 5084820 Picture of this exploded pillow Photo-21
8 14 1536 97 422856 5084742 Lobate flows. Having some trouble with navigation. Looks like there is more sediment. Collapsed area - debris on top and in hole.  
8 15 1538 94 422856 5084742 Lots of broken up lavas. Very glassy. Looks like young lava - a lot of fragmented pieces of rock. Photo-2
8 16 1538 99 422988 5084874 Young lobate flows, a bit of sediment.  
8 18 1537 95 423176 5085015 Heading across young lavas to the east  
8 18 1538 92 423015 5084896 x=3015 y=4896. Crab on top of collapsed area. Photo-2
8 19 1538 106 423025 5084898 Lots more sediment on bottom of pits. Ropy lavas. Photo-24
8 20 1537 107 423019 5084867 More shallow collapse.  
8 20 1539 106 423042 5084882 Chaotic jumbled folded area. Crab. Some thin plates that stand up vertical. Glassy. Photo-25
8 21 1539 104 423056 5084871 x=3056 y=4871 good fix on this line. Glassy flows.  
8 22 1538 105 423068 5084862 Large drained out area - flat. Down in a collapse area. Lineated lava flow. Photo-26
8 22 1540 109 423059 5084828 Looks like flow is to the south. Lines heading south. Big broad plain.  
8 23 1540 104 423100 5084854 Flat plain - sheet flow R493-18
8 23 1540 106 423090 5084854 Large flat area. First large lineated area we've seen like this. Photo-27
8 24 1540 107 423099 5084853 Extensive area of sheet flows. Photo-28
8 25 1539 109 423107 5084854 x=3114y=4855 good fix. Collapsed area. Glassy. Photo-29
8 26 1538 111 423135 5084821 Up on a more solid surface. Young lobate flows.  
8 26 1538 110 423136 5084867 young lobate flows R493-19
8 26 1538 108 423136 5084867 x=3136 y=4867 good fix. Photo of crab. Extensive pockets of sediments. Back on the roof of a pit. Photo-30
8 27 1538 111 423147 5084867 3147 4867 good fix. Photo of skylight. Photo-31
8 28 1537 115 422990 5084680 More jumbled chaotic area.  
8 29 1540 107 423156 5084856 Glassy jumbled flow. Photo-32
8 29 1541 107 423174 5084865 x=3174 y=4865 good fix. Photo-3
8 30 1541 110 423188 5084860 Mounds of jumbled sheets. Glassy. Some sponges - very small. Photo-34
8 31 1541 121 423194 5084854 More mounds of jumbled lavas. Slightly deeper. Photo-35
8 32 1542 107 423272 5084885 Still in young jumbled lavas Photo-36
8 33 1541 105 423218 5084860 x=3217.5 y=4859.7 good fix. Giant pillar, wall structure, about 4 m tall. Photos 37 - 40 Photos
8 34 1538 114 423209 5084854 Lots of collapsed areas, young lobate flows at bottom. More spires up ahead.  
8 34 1538 103 423209 5084854 Picture of lava spire. Photo-41
8 34 1538 103 423209 5084854 Spires R49321
8 35 1537 110 423209 5084854 We're in an area where the eruption may have occurred. Deepest drainout area. Photo-42

Photo-43

8 35 1540 111 423218 5084859 Intact structures. More pits. Photo-44
8 36 1537 106 423165 5084764 No sign of any venting so far.  
8 36 1538 115 423165 5084764 Jumbled sheet flow at bottom of pit area.  
8 37 1539 112 423088 5084636 More jumbled lavas. Photo-45
8 38 1539 107 423284 5084848 Folded back piece of lava - very shiny.  
8 38 1539 106 423291 5084844 Jumbled up crust is very thin.  
8 39 1540 112 423293 5084841 Into flat area again - lineated lavas.  
8 39 1540 106 423059 5084494 Jumbled lava. Spires. Photo-46
8 40 1538 110 423313 5084843 Series of intact areas with spires holding them up. Lobate flow on top.  
8 41 1538 109 423291 5084792 Lobate lavas. Apparently out of collapsed drained out area. Photo-47
8 41 1538 108 423335 5084838 3335 4838 good fix.  
0 0 0     0 0 Lobate flows, very glassy, very little life on them.  
8 42 1538 111 423300 5084785 Photo of young lobate flows. Big rattail fish. Photo-48
8 43 1538 111 423356 5084839 Shallow collapsed pits. Jumbled flow.  
8 44 1538 110 423365 5084840 A holothurian  
8 44 1538 109 423373 5084839 Lobate flows. Surfaces have small pockets of sediment, some brittle stars Photo-49
8 45 1538 109 423383 5084838 Tops of the lobes look glassy.  
8 46 1538 108 425253 5084725 Fragments of the glass in the pockets with sediment. Photo-50 - 51
8 46 1538 110 423392 5084830 Glass in pockets of lobate flow R493-22
8 47 1539 109 423360 5084774 Lobate flows, pockets of sediment with glass. A brittle star. Photo-52
8 48 1539 108 423363 5084774 Problem with the consoles.  
8 49 1539 108 423221 5084598 We've lost console link-no telemetry  
8 52 1539 108 423386 5084812 Looks like we've had some serious snap-loading on the umbilical causing a fiber to break.  
8 54 1539 108 423536 5084972 Turned everything off to try restarting the whole thing.  
9 1 1411 22 423536 5084972 Power is up again  
9 5 1375 329 423436 5084849 They think it's a surface computer glitch that caused the problem.  
9 6 1372 325 423438 5084850 The sub motor isn't starting at depth.  
9 14 1320 295 423591 5084706 Going to bring the sub up to a shallower depth (50-70 m) to see if we can turn the motor on.  
       Dive Summary: R493 was an extension of Dive R492. Collected a couple rock samples, but didn't go to any vents. ROPOS on bottom 0635 - 0848. At 0848 the sub lost telemetry due to snap-loading on the