galvanic corrosion

Hi All,

I found this a really interesting case of corrosion and its affect on timber. This is a carvel planked hull caulked over double diagonal no glue was used in this type of construction. She is ribbed and has a solid backbone structure with sawn keel floors fastened with through fastenings of bolts and copper nails riveted. What you can see is a copper tank, what would you think has caused the timber deterioration? comment about the construction.
What is the style of cradle that supports the hull? how do you go about a repair of this type? make some notes so that we can discuss it next time