Flooding then analysing a core sample

A method for evaluating an underground formation comprises conveying a coring tool 224 to the formation, obtaining a core 302 sample from the formation, and placing at least a portion of the core sample 302 into a processing chamber 300. The core sample 302 is then at least partially flooded, fluid is extracted from it, and at least a portion of the core 302 is analyzed. The extracted fluid can also be analysed and the viscosity of hydrocarbons in the core 302 can be lowered by heating the core by means of heater 241. The core 302 may be a core 302 sampled from a sidewall of a borehole.