Dictionary:Horizontal-loop method (HLEM, HEM)

{{#category_index:H|horizontal-loop method (HLEM, HEM)}} A frequency-domain electromagnetic method in which coplanar (usually horizontal) transmitter and receiver coils separated by a constant distance are moved over a survey area. The primary field is nulled and then in-phase and quadrature components are measured. Also called horizontal coplanar, Ronka EM, and slingram. See Figure E-7.