So many sea shells are found all over the Mohave desert. It could have been one huge Ice wast land with active volcanic activity brewing underneath. Volcanoes strenghten, break the surface, and begin to melt the ice, turns it into a huge inland lake. Seasonal sea levels and tides could have mixed in the life creating a soup of everything.
Plates are always moving and lifting or lowering the land mass. Until we can monitor what is going on miles beneath our feet it will always be a guess. I pray we don't find anything but rocks, no Indian burial grounds of a family of missing links. I've seen projects halted due to stupid chit found. I'm sure seismic activity goes on every second out west.
Google even says there is a fossil museum in the county we are in.
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