Coring tools including a core tube assembly; a carrier chamber defined within the core tube assembly for storing one or more core samples drilled from a downhole formation having a wellbore fluid therein, wherein the wellbore fluid has a wellbore fluid density; a non-hydrocarbon, non-reactive heavy weight fluid (“HWF”) present within the carrier chamber, the HWF exhibiting a HWF density of about 2 pounds per gallon greater than the wellbore fluid density; a pressure housing cover selectively rotatable between (1) an open position, where the one or more core samples are able to be inserted into the carrier chamber, and (2) a closed position, where the carrier chamber is sealed; and a cover activation mechanism coupled to the core tube assembly and operable to move the pressure housing cover between the closed position and the open position.