More insight in the thirty shipwrecks around Christmas Island

We are now reasonably confident that the 1724 Fortuyn does not lie between 0-30 meters in the water off Christmas Island. We have re-run the priority areas on the south-west side of the island with a more sensitive magnetometer (for detecting magnetic iron objects such as anchors and cannon) than we employed in 2015. Divers have visually inspected all of the promising anomalies without seeing cultural material. Some of the anomalies have been discounted because they appear to have been affected by the magnetic basalt rock forming the core of the island.

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We did some more photogrammetry in the last couple

We did some more photogrammetry in the last couple of days to hone our skills. This time we tried to do an object underwater and chose a mooring anchor. The computer is still crunching the data so we’ll show you the result in the next blog!

Christmas Island is fringed with a thick underwater coral platform. Its width varies and most of it slopes gently before curving steeply downward into the depths. During the last two weeks we have been following up on stories from the Dutch Facebook followers and the Christmas Island community about other shipwrecks here or nearby, in particular the Dutch ships, the 1100 ton Arinus Marinus wrecked in 1821 and the 500 ton Vice Admiraal Rijk wrecked in 1852, but also a lot of others.

The Dutch ship named the Vice Admiraal Rijk was lost on the south-west side of the island in 1852. Three men survived, managing to scale the cliffs and living ashore on raw seabirds for 57 days before being rescued by another passing ship. One of the three men left a detailed account of the wreck and his experience on the island. Around midnight the ship crashed onto the cliffs on the north side of the south-west point, breaking a large hole in the bow before turning out from the cliffs and immediately sinking entirely below the waves, with all sails still set.

We regard the Vice Admiraal Rijk as a useful model for assessing what would have happened to the Fortuyn if it struck the south-west coast. So we placed a major focus on inspecting the north side of the south-west point, carrying out a visual inspection of the anomalies and then swimming abreast along the coral platform. We saw no wreckage.

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We inspected all the anomalies on the north side of the south-west point using divers and then swam abreast along the coral platform

The coral covering on the Eisvold, a 1942 shipwreck elsewhere on the island, is up to 0.5 meters thick, and coral would be expected to conceal smaller cultural objects on a wreck on south-west point. However, if the Vice Admiraal Rijk had broken up on the platform we should have seen objects such as large anchors protruding above the coral. Much of the platform there is only around 50 meters wide, with a vertical drop off into some 90 meters water depth. The Vice Admiraal Rijk must have slipped over the precipice without first breaking up.

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Much of the platform is only around 50 meters wide, with a vertical drop off into some 90 meters water depth

Our theorizing, about whether a vessel striking the cliffs would break up against the cliffs or bounce back from the cliffs and slide off the platform into deep water, was based on accounts of the sinking in 2010, near Flying Fish Cove, of the asylum boat SIEV 221. Residents saw that that vessel was trapped between the swells and the backwash, in a ‘washing machine’ effect.

At the south-west point we saw a lot of small pieces of plastic bags suspended in the water column –  plastic brought from Indonesia on southerly water currents, then trapped close to the cliffs in the same washing machine effect. It appears then, that this would trap small items such as plastic bags, and even a medium sized object such as the SIEV 221 (a light wooden fishing vessel probably under 20 metres). However, probably not such a large object as the 35-metre hull of the Vice Admiraal Rijk. If this wreck has not been trapped by the violent pushing of the waves and swells, then probably the larger, 800 ton and 44-metre long Fortuyn wouldn’t either and may have slipped well beyond the 30-metres depth limit of our search.

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At the south-west point we saw a lot of small pieces of plastic bags suspended in the water column – plastic brought from Indonesia on southerly water currents, then trapped close to the cliffs in the washing machine effect

Will we ever know? There is a slight chance of finding the wreck at Cocos Keeling. We will find out in the next coming week! The diving on Christmas Island gave us lot of new insights on other – some of them also Dutch – wrecks and a list of 30 shipwrecks that may have been foundered close to Christmas Island. School children have been taught about their past and the students on the project, me and Shinatria, have had a great time so far, learning enormously about the search for shipwreck. But we are not ready yet!

Cocos Keeling, here we come!

 

 

 

Over Maritiem Programma

Het Maritiem Programma van de Rijksdienst voor het Cultureel Erfgoed houdt zich bezig met het onderzoek naar scheepswrakken, bruggen, havens en andere maritieme landschappen. Het doel is om kennis, onderzoek, beleid, samenwerking en educatie op het gebied van maritiem erfgoed in Nederland een stevige basis te geven. Het programma loopt van 2012 tot en met 2015.

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