Wondering what part was the most radioactive after the explosion

Initially after 10 seconds of the explosion, which area, or single point could have been the most radioactive in the core? Probably melted fuel or something else? This has been bugging me for a long time, I like to think that point was probably over 1000 Sv/h. But above the roof, about 100-150Sv/h because of Inverse Square Law and etc.