I must say that there are several people on this list who are far better informed on geology than I am. I'll consider a Great Debate but only if it is focussed on areas where I regard my personal knowledge or readily available sources as adequate.
That reply pretty much hit my limits on this subject barring another good internet source (there WAS a good page on reconstructing the environment where the Morrison Formation was deposited from the geology, but I think it's gone now - at least its moved from where I found it and I couldn't find it when I tried google).
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