Yes, but only if one can build with stone. I built my base in one of those Stonehenge-like circles. I used the indestructible stones to support log beams rather than using stilts. I had to raise the ground up to the second level to place a fire there before I could build with stone.

Once I could build with stone, I pick-axed the column of earth and replaced it with a shaft of 2 x 1 stone blocks. I placed the first two side by side to form a 2 x 2 base then rotated the next 2-block tier 90 degrees. I capped the shaft with a 2 x 2 stone floor piece. The cap protrudes above the surrounding wood second floor by 20-25 centimeters. Not perfect, I know, but it keeps me out of the fire.

I have seen posts where fastidious vikings build their fires on the ground surrounded by floor tiles and then snap a floor tile into place in the fire. They prefer not to look at the ground.
If one carefully aligned the top of an earth column with the surrounding floor tiles perhaps one could do the same.

An adventurous viking might then pick-axe the earth column in hopes that the fire and its associated floor tile would remain in place.