I haven't been able to find a collection of BLU's physical attack placement in the skillchain system.
Post your findings below to help compile a master list that can eventually be used to update a skillchain chart. I'm not too keen on exact elements, so I'm going to equate them to commonly used WS's (it's what helps me remember it at least).
Claw Cyclone = Fast Blade (closes Distortion)
Jet Stream = Combo (closes Fusion)
Jet Stream would be Thunder element (same as Combo)
Sickle Slash would be Dark element (same as Penta Thrust)
Screwdriver would be Light element (same as Blade:Rin or Power Slash)
and a couple others I've heard:
Bludgeon is Fire element (like Burning Blade)
Smite is Wind element (like Gust Slash)