Korach Swallowed by Sinkhole?

I don’t have the IBN EZRA in front of me to look up but since the “PI HAARETZ” one of the ten things created during twilight of ErevShabbos I would not think that it is a sinkhole as we describe it.

http://www.hebrewbooks.org/pdfpager.aspx?req=53076&st=&pgnum=54

To continue what iacisrmma was saying; The Mishne describes 10 items that were created during twilight of erev shabbos, Pi Haaretz was one of them. These are things that are above the natural order- which is why they were not created during the 6 days themselves, but still part of the physical world, not totally spiritual, which is what shabbos the 7th day represents- hence they were created in the time between the 6 days of creation and the actual start of shabbos.
Moshe specifically asked Hashem to make a new creation- V’Im Briya Yivra Hashem-, to show everyone that Korach was wrong.
Yet, The Ibn Ezra in 16:30 argues with those who say Briya means a new creation, and that it wasn’t something new or special- but like any other earthquake (I think his description more resembles an earthquake than a sink hole, because he talks about countries, medinot, being split- a sink hole would be in a specific small area). He then continues in passuk 35 to say that Korach himself was not swallowed but was burned up with those who brought the ketores.
The RaMBaN argues with the Ibn Ezra and stats Briya has to mean a new creation- and the novelty wasn’t the earth swallowing people- because that happens a lot – he specifically uses the term Ra’ash, meaning earthquake, but the fact that it closed up as if it never had opened, like a mouth opening to swallow something and then closing- that was the supernatural part. Rashi also holds it was a supernatural event