Instrumented core barrels and methods of monitoring a core while the core is being cut

摘要

A formation core analysis system (34) can include an inner barrel (62) and a toroidal electromagnetic antenna (66) which transmits electromagnetic signals into a formation core (40) when the core is received in the inner barrel. Another formation core analysis system (34) can include an inner barrel (62) and multiple longitudinally spaced apart electrodes (68a,b) which electrically contact a formation core when the core is received in the inner barrel. A speed of displacement of the core into the inner barrel may be indicated by differences between measurements taken via the electrodes as the core displaces into the inner barrel. A method of measuring resistivity of a formation core as the core is being cut can include transmitting electromagnetic signals into the core from a toroidal electromagnetic antenna as the core is being cut by a coring bit (38).