The Titanic is corroding and very interesting corrosion products are being discovered. The structure, chemistry and mineralogy of the corrosion products are allowing scientists to gain insight into the geochemistry of iron and other metals that were accidentally introduced into this deep sea environment. Since the Titanic was a brand new ship and she had not even completed her first voyage when she sank, this allows for a well-controlled scientific study.
|The most obvious corrosion products on the Titanic are rusticles. They resemble stalactites and can reach lengths of tens of centimeters. The rusticles have a smooth red outer surface made up of iron oxyhydroxide. When a rusticle is broken open the core is a bright orange color. The needle-like crystals that make up the core are called 'goethite' [FeO(OH)].|
Rusticles covering Titanic bow When a biological activity test was performed it was shown that the rusticles grew in the presence of bacteria. The bacteria are a sulfate-reducing species that grow rapidly under anaerobic (no oxygen) conditions.
There are other unusual forms of corrosion that exist on this magnificent wreck, and these are 'rust flows' and 'rust flakes'. The rust flows are predominantly found on the deck of the Titanic and successive analysis has lead to the fact that they spread at a rate of 10 cm per year. The rust flakes are very similar in composition to the rusticles. They are a mixture of goethite and lepidocrite, both minerals formed in the presence of iron, and suggest bacterial colonization as well.
The study has shown that biological activity in the sea water plays a very significant role in the corrosion of the Titanic. It is now that we know that these bacteria are essential for the formation of rapidly spreading rust flows and rusticles.
One of the things that is now certain is that Titanic will eventually be destroyed by nature. In spite of the lack of oxygen at that depth, iron eating bacteria continue to eat away at Titanic structure and eventually the wreck will collapse on itself. The estimates seem to range from 75 to 90 years. Despite the difference in time there is now no doubt that all to soon there will be nothing left of Titanic except memories, and Internet sites. Although the wreck's condition is too poor to consider raising, the company RMS Titanic Incorporated has been raising items from the wrecksite for several years, and displaying them in a touring exhibit. (reference)