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					Ancillary Data
Tides: HW 04.28              (4.4m)
       LW 10.52               (1.2m)
       HW 16.51               (4.7m)
       LW 23.19               (1.2m)


The sidescan was carried out on the 29/06/2011. 4 lines were taken with 100m spacing at:
Line 1: 8:50:40-8:54:40
Line 2: 8:55:42-9:01:42
Line 3 (1st time): 9:02:44-9:08:42
Line 3 (2nd time): 9:09:42-9:14:43
Line 4: 9:18:42-9:22:45
(Times in AST)
 The towfish had approximately a 70m swath (varied between 67m and 72m depending on the depth
of the water column) and a layback of approximately 3.12m (depth data of the towfish was not
available, therefore an arbitraty depth of 1.8m was chosen as the midpoint of the reasonable
extremes of depth the towfish on a 3.6m line could reach (minimum: 1m; maximum: 2.6m)) . The
sidescan data that we received was limited by the fact that there were equipment issues (the
program was not applying TVG on the first track). Also a large ship was moored close to line 3 and
many fishing boats and yachts were around, so lines had to be adjusted. The wreck of the Matiria
marigo was surveyed and 4 distinct benthic areas identified and classified as Wd.S.Bk.Sh (Weed,
Sand and Broken Shells), M. Wd. Sh (Mud, Weed, Shells) and M.fS.Bk.Sh (Mud, Fine Sand and Broken
Shells) on the Habitat Map. In the region labelled as M.fS.bK.Sh. bedforms with a height of 0.9m and
a wavelength of 5.46m could be recognised. From the sidescan data it was calculated that the height
of the boat was approximately 2.09m, with a part 3.84m tall protruding ¼ of the way along the boat.
However these may not be accurate results as it was difficult to determine which parts of the wreck
were making which shadows on the sidescan.

Grab 1 "little wreck" site

Time: 10:45 BST
Depth: 23m depth
Location: 34631 N, 183297 E

A grab sample was taken at this location to try and sample as close to the wreck as possible. Due to
the boat drifting it was in fact djdslkjkm away from the wreck site. The appearance of the sediment
was that of black mud with a thin yellow surface. Once the sediment had been sieved, in the first
sieve (10mm mesh size) the following species were found:
     Nereis diversicolor (Ragworm)
     Ascidians (not identified to species level)
     Brokens Porifera (not identified to species level)
     Juvenile Sipunculids – (not identified to species level)
   Megalomma vesiculosum (Tubeworm)
   Myxicola infundibulum (Tubeworm)
   Trivia monacha (Gastropod)