Re: Precambrian geology (1)

Jonathan Clarke (
Mon, 12 Apr 1999 06:54:23 +1000

Greetings Allen

Allen Roy wrote:

> Biostratigraphy is acceptable over a local (a few hundred miles in any
> direction) area but not usually accpeted on a global basis.

What criteria do you use to decide when the biostratigraphic succession of one
area is not longer is no longer applicable?

> John Woodmorappe has done alot of literary research which shows that
> radiometric ages are not internall nor externally consistent. I refer you
> to his publications.
> I believe that Creationary Catastrophists put most emphasis on
> lithostratigraphy. Global correlation may not be possible. Within the
> asteroid impact flood model, the stratigraphy will be affected greatly by
> relationship to impact sites. While some impacts would make deposition
> over large parts of the globe, most would only affect smaller regions.

What criteria do you use to descriminate between impact and non-impact related

> At Grand Canyon, there are proposed lines of demarcation for the beginning
> of the Flood and post Flood events such as the carving of the Canyon.
> However, my point was that just because we might consider the great
> unconformity below the Tapeats Sandstone as the initial point of the Flood
> here at Grand Canyon, that may not mean that the same holds true for some
> other unconformity between supposed Pre-Cambrian and Cambrian eras
> somewhere else. Each site would have to be interpreted within it's own
> context or setting. In general, it is usually proposed that the line of
> demarcation for the initation of the Flood catastrophe is the general lack
> of fossils below and fossiliferous strata above.

Is you approach thus similar to that of Tas Walker's

> Allen

God Bless