Tagarchief: shipwreck

The Hanseatic city of Stralsund

Studying maritime archaeology in Esbjerg: Field school and summer events

We have been very busy the last few months with school, traveling and celebrating the holidays. That is why we will take you a few months back and tell you about all the exiting things we have been doing since May.

The International Viking Market

A few weeks before our final exam of the year, the International Viking Market was held in the Viking Centre in Ribe. To gain extra information about the Vikings for our exam, but also for a nice day out, we had organized a trip to the Viking Centre with MASE. In the Viking Centre people dress up and live like the Vikings did, and it can be compared to the Dutch theme park Archeon. Houses, food, games, everything was made and done as it would have been in the Viking Age hundreds of years ago. We went into different houses and even had the change to feel like Ragnar Lothbrock, by sitting in the Viking throne. We played Viking games (board and throwing games, no beer involved J) and witnessed a Viking battle and a horse show. On the market itself, they sold everything that would have been used during the Viking Age. The people who sold their goods came from all over Europe. It was a very interesting and nice day, and we learnt a little bit more about the Vikings.

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Field school

The field school started on the first of June., and took place in Mukran on the island of Rügen, Germany. We stayed on the campsite of a hostel in Prora. This area is famous for the colossal hotels that were built for Nazi-tourism. The hostel itself had been renovated from Nazi-hotel-ruin to the Jugendherberg where we stayed. For three weeks we dived at a 16th century wreck, probably of Danish origin. We made drawings, photos and videos of the wreck, and also got coordinates so we have the exact location of the wreck. The wreck had first been documented in the mid ’80’s and since then a lot of archaeologists and divers have had a look at it. The documentation of the wreck was however not up to today’s standard, and that is why it was up to us to make a final and exact recording of the wreck. During previous investigations quite a lot of finds were recovered. Therefore, we also had a look at these finds. The finds of the wreck were mostly located in Schwerin, a two-hour drive from Prora. Here we documented all the finds. There were guns, one wrought iron gun and a bronze gun, a lot of wooden artefacts, pottery and metal objects. These finds were photographed and the interesting ones were also drawn. For the two guns a photogrammetry model was made, so we can have a good look at them in 3D.

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Every day there was a dive team and a land team. The dive team was split up in two teams, one would dive in the morning, the second group would dive in the afternoon. The wreck needed to be cleaned first, which took much longer than expected, since the wreck was totally covered with seaweed and rocks. All the timbers needed to be tagged and drawn separately. Once the wreck was cleaned and the timbers were tagged, a diver with a GoPro could film the wreck in order to make a photogrammetry model of it. This coming semester we will work on the model and other documentation, and write a report on the wreck. The land team was responsible for the finds. These finds were given a number, were drawn and photographed. They also worked with a Total Station, to shoot the positions of the shipwreck.

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Besides all the work we had to do during the field school, we also had a few days off, when the weather was ‘bad’. Since the site was located on the Baltic Sea coast, an easterly wind caused high waves, which was too dangerous to dive in as the site was really close to shore and only 3 meters deep. But although we couldn’t dive it was really beautiful, sunny weather. We spent those days off in the beautiful nature park on Rügen, in the Hanseatic city of Stralsund, and walking and cycling on the island. It was an amazing place to be, with a lot of history and beautiful nature.

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Sailing in Roskilde

Only one day after we came back from the field school, we had another trip planned. This time we went back to Roskilde. The first time we went there, we spent our day looking at how Viking boats were built and how the Vikings lived. This time we got the experience at how to sail like a Viking! We sailed on a replica of a clinker-built boat, that was built originally in Norway. First we needed to row out of the harbour, before we could start sailing in the Roskilde Fjord. During the 2 hour sailing trip we learnt all about rigging, sailing and steering. We did a lot of different sailing-techniques, which made it really exiting.

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Introduction first-years

After a two-month holiday, we and other members of MASE organized an introduction for the new first year students. We went to Ribe, the oldest town of Denmark, where we got a tour from the Viking Museum through the town. It was really interesting, and even though we had the tour last year as well, we still learned some new things about the town. After the tour we had some free time, so we showed some of the people some nice places in the town. Afterwards we headed back to Esbjerg, where we had a nice barbeque to finish the day.

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Classes have started again. In the next blog we will give an overview of these classes and what can be expected from them. Until next time!

Goddag!

Robert de Hoop & Nicole Schoute

And then it was the last day…

We have spent the couple of days approximately 20 hours underwater, with each time effectively 25 minutes dive time at 24 metres. We have covered a large area and managed to map the site reasonably well. We go back with measurements, film and photo footages, drawings and observations. Now we have to put this all together to create a good site plan and to answer our scientific questions. We have it all and will thus be able to come up with a recommendation for the future, and perhaps a future excavation proposal, depending on the further analysis of the results. It’s all very exciting!

One thing is sure, we had a great time working together with the different groups. I would like to thank all of them, not only for the diving but also for all the discussions we had, the exchange of knowledge and all the fun. In the end, a beautiful project like this should be enjoyed, and we did with a smile even while making days from 5 o’clock to 23h.

So thank you, the team in Ramsgate:  Mark James, Alex Hildred, Dan Pascoe, Johan Opdebeeck, Pete Magowan, Mark Hobbs, Graham Scott, Paolo Croce, Thijs Coenen and Kester Keighley

The lovely Dan (Poppy) and Ben of our ship The Predator (project savers)

Alison James, Angela Middleton and Mark Dunkley from Historic England

Peter Holt for being our telephone hotline for Side Recorder

Peter Hamer for equipment maintenance and delivery

Pidge the cook

Kai Dieho the camera man

Willemien van de Langemheen and Debbie Hickman for the wonderful job they did to communicate the project to the outside world and to maintain contact with the press

And last but by no means least: Ken Welling, the licensee of the Rooswijk shipwreck, for sharing the enormous amount of information he gathered about the site with us, as Rex Cowan did, thank you both.

It was a huge success and let’s do it again!

Martijn Manders

Photo above: The team! From left to right: Martijn Manders, Thijs Coenen, Ben, Dan (Poppy), Peter Magowan, Mark Hobbs, Paolo Croce, Kai Dieho, Johan Opdebeeck, Mark James, Alison James, Alex Hildred, Dan Pascoe, Kester Keighley (missing: Graham Scott who took the photo!)

 

 

The Rooswijk 1740, an update

Today we give you a short update about the work that the joint Dutch-English team of archaeologists is doing on the Rooswijk shipwreck.

The Rooswijk was a Dutch East Indian (VOC) ship that sank on an outbound journey on the Goodwin Sands in the UK, one day after it left the Texel Roads. All hands were lost and the wreck is now lying at approximately 24 metres depth.

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The dive team that worked on the site in 2005 gathered a  lot of information on site and lifted – amongst others – silver and gold coins and silver ingots. The information gathered at that time has not been published yet, but also lacks sufficient context with the ship construction.

Historic England designated the wreck site in 2007 under the Protection of Wrecks Act 1973 (https://historicengland.org.uk/listing/what-is-designation/protected-wreck-sites/wreck/rooswijk).

Current information has shown that the site is under threat of erosion of the seabed. The Goodwin Sands is a very dynamic area with huge sandbanks moving constantly.  This also became evident by comparing sonar recordings of 2015 and July 2016.

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The team wants to investigate how much the site is threatened, but also where this extra information to connect objects to the wreck can be found. The current research could lead to an extensive excavation which may possibly be conducted in the next coming years.

Before such an undertaking can be executed more information should be gathered about the condition of wood, iron and other material, about the best place to start an excavation and how this research could be best executed.

The team consists of archaeologists from the Cultural Heritage Agency (RCE), Historic England, the former dive team working on the site in 2005, Wessex Archaeology (the contractor for Historic England) and MSDS Marine, the current dive contractor.  We are working on the dive support vessel Predator from Essex.

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We are now 5 days on our way. The sun is shining constantly and the first days the weather was very good on the site. The visibility as well (approx. 2 metres). However, wind has picked up from the wrong direction now and we have lost a few tides on Thursday and Friday.

The site has however been found, canons have been identified and we are now working on mapping the Rooswijk shipwreck in order to bring back as much information as possible to start planning method, cost and people needed for the much bigger research that we may execute again with a large international team. Other options will also be taken into account  like (temporary) in situ preservation.  This all depends on what we will find.

The diving will finish on the 15th of September. The project already generated a lot of publicity and general interest in the Netherlands as well as in the UK.

More about the Rooswijk project:

Historic England (press release)

Cultural Heritage Agency (in Dutch) (persbericht)

Follow the project on Twitter using #Rooswijk1740

Continuing the Van Bosse research on Tarama: agreeing on future activities

The past few days were devoted to exploring the possibilities to learn more about the wreck Van Bosse which sank in 1857 off the coast of Tarama. By conducting several interviews with residents, who have been narrated stories about the wreck by their ancestors, but also with information from local books and archives we are able to develop scenarios about how the ship must have sunk after being leak bumped on the reef. This again helps us with the search for the wreck itself.

We have found objects, like an anchor, a bottle of gin, a huge chest and shards of major Chinese jars that may also have been on board the ship. But parts of the ship itself are still not found. Dr. Ikeda and Mr. Sasaki will focus their attention on this in November. Using a metal detector they will search the impact site, where most objects are found and everything in between will be swum and explored.

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The beach of Tarama at the spot where the Van Bosse ship presumably sank

At the same time they will continue to conduct interviews with the people of Tarama who know the stories about the wreck. An information project with the elementary school will be launched. In November, the children on the island can meet archaeologists and interview them for the project. In the Netherlands and Germany we will do further research into the archives.

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Meeting with the head of the island

The Van Bosse project is alive! It’s interesting and amazing to see how excited everyone is. The administration of the island would like to do more with the story and the wreck site. It would indeed give the particularly beautiful diving at Tarama an additional cultural and historical dimension. Then it becomes even more worthwhile to travel over here and visit this island paradise, voted one of the most beautiful municipalities of Japan.

Martijn Manders, maritime archaeologist / Head Maritime Programme RCE

Photo at the top: the highest point of the island, about 30 m, with a 15 / 16th century lighthouse

 

Searching underwater for the Van Bosse ship (1857)

A team of underwater archaeologists consisting of two members of the Japanese National Committee for Research and the Examination of Underwater Cultural Heritage Dr. Ikeda and Dr. Kimura, as well as mr. Sasaki from the National Museum of Kyushu and mr. Manders from the Cultural Heritage Agency of the Netherlands has arrived on Tarama island. This is one of the most Southwestern Islands of the Japanese archipelago, actually very close to Taiwan.

In November a Japanese team of professional archaeologists and sports divers associated with the only dive school on the island – Jaws 2 – will map and assess the site of the Van Bosse wreck and make it accessible for the sports divers who spend their holidays on the island. The visit now in August is mainly initiated as a start of the project about the Van Bosse shipwreck which includes also educational elements and archival research in several countries. The 22nd of August the team was welcomed by the department of education of the island that effectively is responsible for the management of this and other archaeological sites. They have assured us that all help in this is welcome. After this meeting we went to the dive shop to sort out our gears and then settled down in our condo which we share together.

The evening was used to discuss the possibilities to find elements of the wrecksite underwater and to pinpoint the exact place of wreckage, which is still not completely known. Dr. Kaneda wrote in 2001 an article ‘Historical Investigation concerning the Dutch Ship Van Bosse Wrecked Off the coast of the Tarama Islet’ and this article has also been discussed between the archaeologists in order to find out what the chances of finding wreckage are and what kind of research should be further conducted.

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The morning on the 23rd we were up early to go diving from the beach to the place where the ship according to accounts must have wrecked and where a fisherman has salvaged many pottery over the years. Indeed by walking on the beach we collected many pottery shards of different kinds. These are however mainly Chinese.

The coastal waters around the island Tarama are very shallow and abruptly become much deeper with here and there dangerous rocks ending just a few meters under the sea surface. For somebody who is not acquainted with these waters, it is a dangerous place. The underwater world, just at the edge of shallow and deep is however stunningly beautiful!

The second dive today was in deeper waters with the dive shop Jaws 2 and their ship. At 28 meters of depth, again on the edge of where the water gets very shallow and  near the place we had been diving in the morning, a considerable amount of pottery shards from large Chinese storage jars can be seen lying on the seabed. Were these used at the Van Bosse ship? It came from China…

Van Bosse 2016 duik 2 (19) blog 2

Also an enormous iron crate was discovered. Definitely something has happened here. The area however is large and the research in November should reveal the size of the site and maybe even also the location of impact: where the ship has hit the reef.

Tonight we will talk with an old fisherman. Let’s see if he can help us out.  Tomorrow, the 24th we are invited by the head of the island, similar to a mayor and in the afternoon we have a round up with the advisory board of the heritage of Tarama. Then up to Fukuoka for further talks at the Kyushu National Museum, our partner in shared heritage management.

Martijn Manders, maritime archaeologist/Head Maritime Programme RCE

Japanese – Dutch research on shipwreck Van Bosse about to begin

In August, the Cultural Heritage Agency of the Netherlands (RCE) is joining forces with the Kyushu National Museum to conduct an exploratory research on the Dutch shipwreck Van Bosse. The research focuses on exploring opportunities for mapping the Van Bosse and providing accessibility to the wreck for local sports divers. The project is a continuation of existing cooperation with Japan in the field of maritime archeology within the framework of Dutch Shared Cultural Heritage policy. The site of this Dutch wreck is already protected locally. The ship was built in Germany, but registered by the Dutch owner in Rotterdam.

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The ship Van Bosse was originally built in 1854 in Germany. The 665t big three master barque, which was employed by the Bonke & Co. Trading in Rotterdam was on its way from Shanghai to Singapore when it sank during a storm in 1857 at Tarama island, Okinawa prefecture. Luckily all 27 people on board survived, but before they could return to Batavia in the Dutch East Indies, people stayed several months in Okinawa and integrated into the local community.

The story of the sinking of the Van Bosse and the interaction of the people of Tarama with the crew of the ship are recorded in detail. It gives us a good insight into the history of the Ryukyu Kingdom and the relationship that it had with foreign powers at a time when the self-isolationism of Japan had just been lifted. It is striking that until few years ago nobody knew exactly what ship it was, although the story of the sinking of the ship was well known. We know it now, thanks to extensive research in Dutch archives.

The Van Bosse shipwreck is registered as a Village Historic Site (オ ラ ン ダ 船 遭難 の 地: Oranda-sen Sonan no Chi ~ Site of Dutch ship wreck). It lies on a reef at depths ranging from a few meters to about 30 meters. Over the years, an iron anchor was lifted, which is on display in a local museum, and several other finds such as a complete Lucas Bols gin bottle and some salvaged porcelain shards.

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However, there’s more to be found. Despite the protected status of the ship an archeological significance assessment of the wreck site has not yet been made. This will take place this autumn and is having its official start now in August, with a first joint visit to the site. Ultimately this will lead to a management plan for the site in which all interests should be taken into account. The Van Bosse wreck is already dived regularly by sport divers. A local dive shop has voluntarily undertaken protection of the site. The local authorities are working on an active promotion. The aim is to use the wreck to attract more recreational divers to the island. But what measures are necessary to facilitate an intensive visit of sports divers? How, for example, can the remains underwater be protected while still visible and accessible to visitors? And there is need for more information about the site to allow divers to fully experience the wreck and its history when they are underwater.

In August Dr. Ikeda from the University of Okinawa, Dr. Jun Kimura of the Tokai University in Tokyo (with students), Randy Sasaki of the Kyushu National Museum and Martijn Manders (RCE)  will officially start the project. In November, the Japanese partners will conduct follow-up research historical research in the Netherlands and Germany will be coordinated by the RCE.

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Late August the World Archaeological Congress (WAC http://wac8.org/) will be held in Kyoto, Japan. As part of the Japanese – Dutch cooperation Martijn Manders and Yoshihi Akashi will represent the Fukuoka prefecture and chair the session ‘Global Perspectives on Underwater Cultural Heritage Management’. The presentations will elaborate on universal values of the underwater cultural heritage management, what needs to be improved in management and the way countries can cooperate in the protection of underwater cultural heritage. This fits exactly with the way the research on the Van Bosse shipwreck is implemented: a collaboration between various parties in the country where the ship sank, Japan, and the country of origin, the Netherlands.

Martijn Manders, maritime archaeologist/Head Maritime Programme RCE

Scheepswrakken voor de kust van Suriname

De Tweede Wereldoorlog wordt in het Caraïbisch gebied gekenmerkt als een oorlog waarbij voornamelijk op zee werd gevochten. De Duitsers probeerden met operatie Paukenschlag de goederen toevoer, en met name de toevoer van grondstoffen, stop te zetten. Ook vrachtschepen uit Suriname werden slachtoffer van deze operatie. Een van de schepen die slachtoffer werd van de Duitse onderzeeboten was de Frank Seamans, een meer dan honderd meter lang Noors vrachtschip die met een lading bauxiet vanuit Suriname onderweg was naar Trinidad.

In het kader van mijn thesisonderzoek heb ik samen met het personeel van de Kustwacht van Suriname, de RCE en enkele duikers verkenningstochten gemaakt om het wrak van de Frank Seamans te zoeken die voor de kust in de Atlantische Oceaan moet liggen. Helaas konden wij niet achterhalen waar het schip was, omdat de posities niet nauwkeurig genoeg waren. Er is geprobeerd met de dieptemeter van het schip alsnog een indicatie te krijgen van de locatie, maar dat leverde niet veel resultaten op. De plek, 50 km uit de kust is ongeveer 30 meter diep, maar helaas ook nog altijd zeer modderig. Er is dus geen zicht onderwater maar wel een forse stroming. Daarom hebben we uiteindelijk besloten om niet te gaan duiken. De risico’s waren te groot.

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De crew waarmee de verkenningstochten zijn gemaakt

Naast de Frank Seamans waren ons nog drie posities van scheepswrakken doorgegeven. Echter alleen de posities, dichter bij de kust en op ongeveer 10 meter diepte, waren bekend. De bemanning van het schip van de Kustwacht kon ons niet dicht in de buurt brengen, omdat niet bekend was hoe groot de wrakken waren, hoe exact de posities die bij ons bekend waren zijn en hoever deze boven de bodem uitsteken. Er waren dus grote risico’s dat het schip in aanvaring zou komen met een van de wrakken. Dit was al reeds met het ons begeleidende schip gebeurd. Daarbij was het water hier nog donkerder en onstuimiger. Netten kunnen verstrikt raken in de wrakken en  daardoor ontstaan levensgevaarlijke situaties. Ook hier dus weer een no-go wat duiken betreft. Al met al wel een teleurstelling maar we hadden dit risico ingecalculeerd. We gingen er op uit om ervaring op te doen en we hebben dit opgezet om te kijken hoe we in de toekomst projecten kunnen oppakken met onze partners.

Het is ons duidelijk geworden dat de samenwerking tussen de Anton de Kom Universiteit, het Ministerie van OWC, de Kustwacht en de Maritieme Autoriteiten Suriname (MAS) onontbeerlijk is. Ten eerste is nog maar heel weinig bekend over de wrakken voor onze kust. Sommigen hiervan zullen mogelijk een archeologische waarde hebben, maar vormen zeker ook een obstructie voor de huidige scheepvaart. Het in kaart brengen hiervan, waarbij een exacte positie, grootte en diepte van iedere obstakel wordt opgemeten is dus geen overbodige luxe. Dit zou bijvoorbeeld doormiddel van surveys met een side scan sonar al kunnen gebeuren.

Ook zou de opslag en het beschikbaar stellen van data die bij andere onderzoeken wordt verzameld (bijvoorbeeld bij onderzoeken naar olie) kunnen helpen om een beter inzicht te krijgen in de zeebodem. Direct aan dit onderzoek zou cultuurhistorisch onderzoek gekoppeld kunnen worden. Met exacte posities en side scan sonar beelden kunnen al indicaties van de aard van de vindplaatsen worden gegeven. Het combineren van onderzoek levert dus een hoop synergie en waarschijnlijk veel winst op wat betreft de inzet van geld en middelen. De komende tijd zullen de nieuwe partners in het maritiem onderzoek in Suriname de handen ineen gaan slaan om de ideeën ook echt gestalte te gaan geven.

Dharwiendre Rambharosa 

Stoffige boeken vertalen naar een interactief 3D model, hoe doe je dat?

Stoffige boeken geschreven in Oudnederlands waarin de bouw van een 17e eeuws schip wordt opgetekend en dat dan vertalen naar een interactief 3D model. Dat is de opdracht waar wij, studenten van de NHL minor 3D, op dit moment aan werken. We gaan met behulp van de beschrijvingen van Nicolaes Witsen oude scheepstypen nieuw leven inblazen met moderne 3D technieken. Zo ontwikkelen we een interactief 3D model dat online beschikbaar komt (in Nederlands en Engels) voor een internationale groep onderwaterarcheologen en maritiem historici. Om jullie een beeld te geven van hoe dat gaat, schrijven we deze blog.

Functies

Zoals in de introductieblog beschreven hebben Ab Hoving en Rene Hendrickx een enorme hoeveelheid werk verricht om het boekwerk van Nicolaes Witsen via een 3D model te ontsluiten. Dit project voegt een element toe aan het model, namelijk een online visualisatie van het 3D model om de bruikbaarheid te vergroten. Binnen het project wordt informatie over de bouw van het 17e eeuws schip toegankelijk gemaakt, onderdelen van het schip kunnen afzonderlijk geselecteerd –en bestudeerd worden met ondersteuning van informatieve beschrijvingen. Het 3D model kan ook worden gedraaid en er is een mogelijkheid om in- en uit te zoomen. Door gebruik te maken van een tijdlijn met daarin de verschillende bouwfases wordt het schip stap voor stap in tijd opgebouwd. Door op de tijdlijn te drukken worden onderdelen op hun plek gezet door middel van een animatie.

Opschonen van het schip

Het bestaande 3D model van het schip is gemaakt in software (Delftship) dat niet bedoeld is voor grote projecten. Omdat wij de pinas interactief gaan maken en het online beschikbaar moet komen te staan moet het model van het schip opgeschoond worden. Het bestaande model bestaat uit te veel informatie waardoor het bestand niet door iedereen gebruikt kan worden. Door alle onderdelen stuk voor stuk op te schonen wordt het bestand veel minder zwaar Daarnaast krijgen alle onderdelen nu textuur waardoor het model realistischer wordt en meer tot zijn recht gaat komen.

Op de foto linksboven zie je veel overbodige hoeveelheid informatie aan lijnen. De overige objecten zijn de opgeschoonde versies. Door dit voor alle objecten te doen wordt het bestand aanzienlijk lichter waardoor het mogelijk wordt om het model te delen via een webbrowser.

Prototypes testen

Het project is ingedeeld in meerdere korte fases, en in elke fase wordt een prototype ontwikkeld Zo worden er meerdere prototypes binnen het project ontwikkeld.. Ieder prototype zal door een testpanel van zes (internationale) experts getest gaan worden. Dit doen we om aan het einde van het project een functioneel eindproduct af te leveren dat aansluit bij de wensen van de gebruikers dus afgestemd op het werk van onderwaterarcheologen en maritiem historici. De thema’s van de test onderdelen zijn: navigatie, het draaien van het model en de functionaliteit van de user interface. Ook de manier waarop informatie opgevraagd kan worden door interactie met het 3D model zal worden getest. De feedback die uit tests komt wordt in opvolgende prototypes geïmplementeerd om uiteindelijk tot een eindproduct te komen wat samen met de doelgroep ontwikkeld is.

Beleving

De extra stap die wij willen nemen gaat over beleving. Het zou interessant kunnen zijn om door het schip te kijken vanuit een ander perspectief en het schip tot leven te zien komen door de bemanning aan het werk te zien of een kijkje te nemen in het magazijn waar specerijen uit verre landen werden opgeborgen. Over de beleving zal komende weken nog verder worden nagedacht. Over twee weken volgt er een nieuwe blog met afbeeldingen van het eerste prototype.

Jord de Vries (Student en projectleider van het Pinas project bij NHL)

 

 

Remote sensing process & the big blue

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Remote sensing

A crucial element in the project is the remote sensing process. The aim is to acquire, process, analyze and interpret the data and to let this follow by diving on targeted locations.

We have acquired the data with a seaborne magnetometer. This device measures distortions in the natural earth’s magnetic field through the presence of iron (or ferrous) material on or under the seabed. The magnetometer is towed on a cable behind the survey vessel, sending readings up the cable to a tablet, which logs the data and provides positioning through a GPS.

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Photo 1: The results of magnetic testing over know iron wreck site, Eidsvold, at Christmas Island. The image on the left clearly show distortions in the earth’s magnetic field, caused by the presence of the wreck. The three lines show the track of the survey vessel. The image on the right show a profile of a transect line across the sight with the clear characteristic ‘dipole’.

The tablet also helps the skipper to navigate along per-positioned lines called transects. These lines have been carefully arranged in mapping software to be straight, and parallel. Narrow line spacing is required to allow sufficient coverage.

Once the data is brought back ashore, it is reviewed on laptops with specialized software. This process allows for the earth’s magnetic field to be displayed and any distortions detected. Interpretation happens next.

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Photo 2: A magnetic anomaly discovered in the post-processing phase of the remote sensing component in the search. The anomaly is clearly seen in the paler contour lines, along with depth contour lines. This anomaly is approximately 85 by 160 meters.

A list of potential sites is produced, and the most promising analyzed more closely. Mapping software allows for the precise positioning for the deployment of divers. Circular shapes are created and placed within the mapping software, which gives a very accurate indication of depths, and can thus inform the dive plan. In this case planning for circular dive searches.

This positioning information is then fed into the tablet, enabling precise navigation to each target.

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Photo 3: Mapping and other specialized software enable the blending of magnetic isometric lines (black) and magnetic anomalies (blue and yellow), with bathymetric contour lines (white) and planned circular dive searches (red).

The entire work flow, carried out by Alex Moss and James Parkinson enables the team to react to information gathered in the field, a sort of ‘reflexive methodology’.

Penultimate day of diving on Christmas Island

Waterlogged is the best way to describe the way we all feel after the last few days. Whether diving or on the boat we have been wet. Some rain showers were so strong it was a drier feeling in the water than out of it! Sadly, our time on Christmas Island is coming to a close and we have not discovered any archaeological material that would bring us closer to the Fortuyn. While we have not yet managed to dive all the identified magnetic anomalies our time is running out. But let’s keep our fingers crossed.

DCIM100GOPROGOPR3506.Photo 4: Me descending down the shotline.

DCIM100GOPROGOPR3534.Photo 5: Alex Moss doing a 30 meter circular search. The other diver holds the line at 15 meter and makes sure the line doesn’t get caught.

Today we dived sites off the West coast and because of the very calm conditions were able to swim survey from Egeria Point northwards to Winifred Beach. The difficulty of finding a site in the 30 meter depth range available to us as divers was made very evident during that transect, as several times we encountered a vertical drop off to far greater depths not more than 50 meters from the coastline. A very small shelf for a shipwreck or shipwreck debris to stay attached to!

DCIM100GOPROPhoto 6: Graeme and Shinatria after their circular search.

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Photo 7: The MV Eisvold shipwreck is a beautiful place to dive!

Our next blog will be the last from Christmas Island, before we go to Cocos Keeling. Stay tuned!

Community involvement and diving

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The very generous involvement of members of the international online community has been fundamental to the progress of the Closing in on the Fortuyn project. Thomas Creemers has sent information from the Netherlands that has fundamentally broadened the list of shipwrecks and the scope of team’s activities on Christmas Island.

Until recently the list of ships known and likely to have wrecked on and around Christmas Island consisted of the Fortuyn (1724), an unnamed Dutch shipwreck (prior to 1744), the Norwegian MV Eidsvold (1942), the Japanese Nissei Maru (1942), the Indonesian asylum boats SIEV X (2001) and SIEV 221 (2010) and the Panamanian registered MV Tycoon (2012).

Thomas has sent the team a wealth of information about two more Dutch ships. They are the 1100 ton Arinus Marinus and the 496 ton Vice Admiraal Rijk wrecked respectively near and on Christmas Island in 1821 and 1852. About the latter we have already written in our previous blogs, but not of the Arinus Marinus!

The Arinus Marinus

After the 1814 Treaty of Paris, Rotterdam merchants bought British ships and used them in the Dutch fleet to the Indies. The Arinus Marinus was one of these vessels, an English frigate, built in 1803 and named the Ceylon. It was purchased in 1815 by a Rotterdam shipping company. In this capacity the Arinus Marinus was taken to the Indies in 1816 for among others the trade in tea.

Photo 1

Photo 1: The Arinus Marinus as shown on a song sheet. This song is about the wrecking of the Arinus Marinus.

In 1821 the ship was loaded in Batavia for a return trip to Rotterdam. The winds took it close to Christmas Island with fatal consequences for the 200 on board, except for four of her crew. These four people floated on a piece of wood until they were found and rescued by the crew and captain of the Danish ship the Souvereign.

The Arinus Marinus had a very special cargo on board: a natural collection intended for the Museum van Naturalien in Leiden. This collection consisted of 15 boxes. Amongst these were:

  • 5 boxes that were full of stuffed animals,
  • two boxes had prepared hides and skins,
  • 4 boxes were full of skeletons,
  • 3 boxes were filled with minerals and rock samples.
  • Also on board were 36 different plants from Java for the botanical garden in Leiden.
  • a black tiger
  • and an elephant!

Photo 2 Photo 3: Loading all the gear for diving!

Diving!

We finished the survey on Thursday so on Friday and we started diving to identify magnetic anomalies! All the planning, survey, analysis and preparation now culminates in a few dives over the coming days when we hope to see something that nature does not produce :a straight line! Nature is glorious, but humans construct materials with straight lines, be it anchor stocks, cannons, or other artefacts. The appearance of a straight line in the coral is a wonderful tell-tale that some cultural material lies below. While nature does not necessarily make straight lines underwater, when it breaks up, coral can result in the appearance of straight lines. Large plate coral literally abounds in the area we are diving. This coral can form a short straight edge when broken, periodically enough to get your heart racing before hopes are dashed.

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Photo 3: Me proceeding down the shot line.

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Photo 4: We drop a shot line at the anomalies and from there we do circular searches up to 30 meter.

We also dived on the MV Eisvold and the Nissei Maru (both WWII shipwrecks) to take corrosion measurements.

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Photo 5: Drilling and taking the corrosion measurements at the Nissei Maru.

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Photo 6: The wreck of the MV Eisvold is a beautiful spot to dive!

 On Tuesday we will leave for Cocos Keeling Islands so hopefully we will be able to dive on all the locations the magnetometer gave us some abnormal reading!