Quickly reconfigurable core barrel head assembly

A core barrel head assembly positionable within a drill string of a drilling apparatus. The core barrel head assembly comprises an upper latch body having a latch assembly for engageably latching the drill string, and a reduced diametric portion below the latch assembly for receiving a seal member. The reduced diametric portion has a lower coupling portion on a bottom portion thereof. The head assembly also includes a lower latch body comprising an upper coupling portion on a top portion thereof, as well as a coupler for removably coupling the upper latch body to the lower latch body. The seal member is installable on and removable from the reduced diametric portion upon uncoupling the upper latch body from the lower latch body. The head assembly is quickly reconfigurable between surface and pump in/underground configurations. Core barrel outer tube components also do not require reconfiguring between these two configurations.