Probing the till beneath Black Rapids Glacier, Alaska, USA

Abstract

A heavy down-hole hammer actuated from the surface by a light composition rope was used to place instrumented probes into the active, 7 m thick, clast-rich till underlying a site on Black Rapids Glacier, Alaska, USA, where the ice is 500 m thick. A till penetration of about 2.5 m was obtained, and greater depths seem possible. The probes measured pore-water pressure and two axes of tilt, which they broadcasted, without wires, to a receiver just above the ice-till interface.