The Holocene Impact Working Group think that it was created about 5,000 years ago during the Holocene epoch when a comet impacted in the ocean, and that enormous megatsunamis created the dune formations which later allowed the crater to be pin-pointed.
That it was created about 5,000 years ago during the Holocene epoch when a comet impacted in the ocean, and that enormous megatsunamis created the dune formations which later allowed the crater to be pin-pointed. This is what the Holocene Impact Working Group think.