Prince Rupert area Quaternary Geology 11-98

I see nothing in the literature but, looking at the mountains visible from Rupert, most have the rounded look meaning they were over-ridden.
This mountain north of town (figure right) is beginning to look jagged peaked -- so probably the ice was something like 4000 feet thick at the maximum. Certainly it was higher than Mount Hays because one can see glacial till at the top.

The fun part is trying to figure out when the ice had withdrawn and vegetation returned.
To that end Archer has documented a beach site at Port Simpson that dates back to 12,440 BP (before present) located fifty metres above the present sea level.

Here are some shells I found during construction of the apartments at 1000 block 3^rd Avenue. According to the Engineering department that is about 100 feet above present sea level and thus may date back to the same time period. We'd be interested if anyone knows of fossil beds locally that are higher. For reference Montreal Circle is about 85 metres.

The following is from David Archer's recent paper:

As an archeologist Archer wants to know where is the best place to look for village sites. Namu dates back to 9000 BP and sites just to the north of us in Alaska go back even further. So far, the oldest village site locally is "only" 5000 years ago (GbTo-34).

The significance of the Port Simpson beach site is that the highest and oldest; previously known marine deposits date from 12,100 and are only 13 metres above present sea level.

(Please excuse the poor figure)

The above information is taken from Quaternary Geology and Geomorphology Smithers Terrace Prince Rupert area, British Columbia, by John Clague (1984).

His interpretation is that Rupert was "deglaciated" 2000 years before Terrace.

Now picture this: Rupert is about present sea level while the sea is 200 metres up the mountain at Amesbury on the Skeena. And the Queen Charlottes are first 90 metres above then 15 metres below present sea level. These quaternary geologists don't seem to mind at all.

Compared to Terrace there is very little "fill" around Rupert. Sure there is some out at the industrial park; and some "colluvium" (fell from sides of mountains) out by the golf course and in Port Edward. Still nothing like in Terrace.

Clague (1984) guesses there was never much to begin with. Another hypothesis is that is was washed away during stormy weather 12000 years ago.

CBC hill on Digby Island is interesting because it's about 100 feet of pure dirt.

So where did all those boulders come from? They are granitic and not local rocks; they have been weathered round and are sorted to some extent. A working hypothesis is that they have eroded from a much more extensive CBC hill over time. The yellow arrows on right point to similar smaller rocks in present hill slope being attacked by erosion.

Many headlands on Digby and Tugwell are similar and I suspect they arrived at the same time.
Presumably floating down the Skeena River from some valley like the Kasiks River at a time when the sea level was about 100 feet above present.

For reference here is Digby and CBC Hill; the pointed arrow is approximately where the dirt with yellow arrows is; and the straight line is where the "in situ" clam bed is.

I will add references to article available on internet about Queen Charlottes etc dating from same era of "deglaciation" on the "reference page" coming soon,

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If you know of local fossils or interesting geology let us know.