Was the Burgess Shale covered by water???

Question

It seems like a high rocky mountain?? was all that covered by water 300 million years before the Cambrian explosion???

Please help!!!

Answer 1

The Burgess Shale was actually formed under water. It is the remains of a shallow bay that had a number of volcanoes around its edge. As the volcanoes erupted there was a huge fall of very fine ash that quickly sank to the bottom of the bay and covered all the life forms and preserved them. Life soon came back into the bay from the surrounding sea populating the bay until the next eruption. The reason that the shale beds are now in a high, rocky, mountain area is due to the tectonic movement of the earth's plates which have pressed together and forced the rocks up to form a mountain ridge.

The Cambrian explosion was not a real explosion, it was a period towards the end of the Cambrian period when a large number of complex life forms can be seen to have developed. It is a very misleading description as it was NOT sudden but covered a time span of many millions of years and, in my opinion, should not be used.