wirral forums

Question for local Geologists.

Posted By: JonnyHill1981

Question for local Geologists. - 6th Mar 2018 2:01pm

Hello all.

My first post, thanks for having me. So who's my goto Geology member then?

Took a morning walk up Bidston Hill and was thinking about it's ice age past, and why there doesn't seem to be large igneous boulders deposited across it.
Surely there would be some dotted across Wirral left over from the last ice age when the ice shelf receeded?
Are there any?

Cheers,
Jonny.
Posted By: JonnyHill1981

Re: Question for local Geologists. - 6th Mar 2018 2:13pm

Sorry replying to myself, still learning the ropes folks!

This is a link to what I meant

en.m.wikipedia.org/wiki/Glacial_erratic
Posted By: diggingdeeper

Re: Question for local Geologists. - 6th Mar 2018 3:11pm

This might be of interest as well CLICKY
Posted By: JonnyHill1981

Re: Question for local Geologists. - 6th Mar 2018 7:08pm

Thanks for the reply and link dd.
Interesting stuff!
Still leaves me with lots of questions though ha.

Cheers,
Jonny.
Posted By: Wally1

Re: Question for local Geologists. - 6th Mar 2018 8:01pm

I'm not a geologist but I am old. I would think that glacial erratics if left
on the tops of sandstone ridges would gradually be move to lower
ground over time so would no longer be visible.

I have seen only one for certain. That was in the foundations of the
old A & E section of Victoria Central Hospital in Croxteth Ave Wallasey
back in the 1950's. The excavation deep into the boulder clay had cut
through and exposed a large erratic boulder embedded in the clay.

There is one possible one on the surface in Central Park Wallasey
assuming it is still there. When I last saw it it was about 4 ft high
well rounded and looked like a dark grey granite - definitely not
sandstone. GoogleEarth view attached.


Description: Possible Erratic in Central Park Wallasey.
Attached picture GlacialErratic.jpg
Posted By: Wally1

Re: Question for local Geologists. - 6th Mar 2018 8:13pm

I should have mentioned that the boulder clay cliffs at Thurstaston
erode out erratic boulders stones etc. and these can be seen along
the beach below the Visitors Centre on the Wirral Way.
Posted By: Greenwood

Re: Question for local Geologists. - 7th Mar 2018 6:42pm

The link put up by DiggingDeeper looks very interesting, but Ye Gods I wish the person writing it had used paragraphs! They make text much more digestible. My (totally amateur) idea on the lack of glacial erratics on Bidston Hill is that, being a high area, it would have been scoured clear and any deposition would have been on lower-lying areas. Smaller ones lying around might later have been used for building or walling. There is a rich variety of erratics (mostly small) eroding out of the cliffs at Thurstaston, well worth exploring.
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