State historic preservation officials are expected to visit Mona Terrace today after construction crews working on the reconstruction of Delaware Avenue on Tuesday unearthed what appear to be several wooden caskets. The discovery brought work at the site, part of a much-heralded $14.9 million federal stimulus project, to a halt while an archaeologist working for the city examined the find. It was not immediately clear how many caskets were unearthed -- and as of Tuesday night, no skeletal remains had yet been found, said city archaeologist Michael Warner. Warner said the work crews noticed the discoloration, including the telltale blackish color of deteriorated wood, and stopped work immediately. "They did a good job of stopping when they did because they're on top of it instead of halfway through it," Warner said, stressing that the investigation is only in its earliest stages. [...]