Base metals markets are very nervous this week, says a London broker. Notes extremely low volumes on copper and aluminum. "I think you'll probably see violent swings on the minor metals such as tin and nickel," he says. Adds that concerns that the tsunami that hit the Solomons and Papua New Guinea Monday could impact production there or in Bougainville could be one reason for LME three-month copper strength. However "it's probably just due to thin trade." LME copper is up 0.5% on the day at a fresh four-month high at $7,013.15/ton. Nickel is up almost 3% at $46,950/ton. Lead is up 1.3% at $1,960/ton.