Only God knows what the earth exactly looked like before the Flood, but I believe it used to be one supercontinent.
Now the question is whether there was an ICE WALL surrounding the round and flat plane of this world?
I don't think so, based on this:
Genesis 8:22 1599 Geneva Bible (GNV)
22 Hereafter seed time and harvest, and cold and heat, and Summer and Winter, and day and night shall not cease, so long as the earth remaineth.
Read the whole chapter...
This was AFTER the Flood, so there was NO COLD and NO WINTER before the Flood and therefore I don't believe there was an ICE wall surrounding this world BEFORE the Flood and that's also why we don't read about the current ICE WALL in the Bible!
The supercontinent started to divide itself (God knows by whatever mechanism) AFTER the Flood:
1 Chronicles 1:19 1599 Geneva Bible (GNV)
19 Unto Eber also were born two sons: the name of the one was Peleg: for in his days was the earth divided, and his brother’s name was Joktan.
My conclusion: There was no ice wall going around earth before the Flood