Great commentary and info, the time scales are mind bending.

@robbutler2095

18 күн бұрын

Thanks - it's remarkable how well-preserved these ancient rocks are!

Thank you very interesting. Aa bad day at the beach 1.2B years ago!

thank you!

Thank you Rob for taking the time to share this insight. It was presented extremely well and simplified enough for those people such as myself who find the subject of geology fascinating yet rather complicated. Perhaps the person in the comments section below - GORDON STALKER , needs a lesson in how Scotland came to be and where it once lay on this great planet of ours. Do they think that Scotland has always been where it is and that this qualifies them to make such ridiculous statements 👍

Amazing stuff. Not heard of this before been a long time since I was in scotland and love assynt region. Cheers

@robbutler2095

3 ай бұрын

It's worth a look next time you're in the neighbourhood....

@mixolydian2010

3 ай бұрын

@robbutler2095 cheers for the videos in general rob.

Excellent stuff. 👍👍👍

I am so grateful for how you transport me to some of my favourite frenquently visited places in and around the assynt duplex that was my mapping project 🙏

Absolutely fascinating!

As usual excellent

Hi Rob good video! Are the inclusions of Lewisian clasts in the layer actually evidence for this meteorite impacting gneiss or couldn’t these have just been picked up by the volcanic slurry which was sent out?

@robbutler2095

11 ай бұрын

Good question. It seems likely that the ejecta slurry ran over an exclusively Stoer Group cover... At least in the preserved outcrop sites, the topography at the base of the Stoer was buried by the time of Stac Fada. So most probably that the Lewisian clasts come from the crater...

Great stuff Rob! Amazing geology presented in a very didactic way. One quick question about it though. If the upper layer of the impact-induced debrite is fine-grained dominated, why has the fluvial on top not simply eroded it all out once it ré-stabilised? How exactly is this relationship of the fluvial sands back overlying the debrite/fine-grained top? I guess it would be great to know a little more about it to try and understand how much the river was actually affected at the moment of this impact. Gui

@robbutler2095

Жыл бұрын

Thanks for the comments. The Stoer Group - once you're above those basal palaeovalleys probably represents a very low-relief palaeoenvironment. The succession comprises fluvial sands and significant lacustrine deposits (that host microbial life). I'd go for something like interior Australia - Lake Eyre - as a modern setting - but of course without vegetation in the mid Proterozoic. So the post impact climate seems to have been in a damp phase - with lots of standing water. The fluvial deposition happens later... and agrades (very little incision at base of fluvial facies in the whole succession) - possibly preceded by some aridity/base-level drop... or simply progradation... hard to go far with this given the sparse 3D preservation of the system on a larger scale.

I live in New Orleans, I'm visiting Oregon on a vacation to see the coastal sight "Devils Punchbowl" while looking around the it, you can sand stone that has fractures in vertical and horizontal line plus black stone that doesn't seem to line up right. I'm guessing it's all millions of yrs of erosion, but it just seems odd. I'll have a video of it on my channel in a few days. We're just tourists but I'd love to hear a professional explanation. Maybe it's an ancient collapse lava tube, I have no idea. I'm a machinist millwright, not at all any education in geology or biology but it is awesome to learn how to read the earth.

@robbutler2095

Жыл бұрын

Have a good trip!

I have a rock that looks extremely like 13:48. Got it in Oban at night when the tide had just went back out. Can I send you a photo?

@robbutler2095

Жыл бұрын

Can do - but it's going to be an igneous rock, plenty of options in the neighbourhood of Oban....

@Wamsyllib

11 ай бұрын

@@robbutler2095 I picked up many different rocks at this time. I’ve tried identifying them with rock identification app but not sure how dependable it is. 2 zoisite apparently is this possible?

Although you/Amor reckon the meteor impact crater is likely to lie under the present day Minch, wasn't this whole area a Laurentian island archipelago that got 'shunted together' by later events (eg docking of Avalonia and Baltica with Laurentia). Would this potentially change the meteor impact crater to be somewhere to the north of the direction suggested by the Stac Fada strata? Thanks for a very interesting series.

@robbutler2095

Жыл бұрын

Thanks for the question. We do know that Laurentian crust, as represented by the Lewisian rocks, continues beneath the Minch Basin to connect with the Outer Hebrides - so at the scale of several hundred km - the landscape here was continuous an not a series of distinct "islands". Further (what is now) west, then the Grenville orogen has yet to form (but will in c 150 Myr after the impact) so - yes, with respect to greater Laurentia, NW Scotland was detached... But - the key for linking lumps in the ejecta to local basement - the Lewisian has distinct tracts with different metamorphism - and that's what Amor et al used to link the ejecta to location of putative crater site. Worth checking out their paper...

Where is that crater located?

@robbutler2095

2 ай бұрын

Not been found - a lot has happened to NW Scotland in the past 1200 million years. It's probably buried (and submerged) offshore...

@Seliotka

2 ай бұрын

@robbutler2095 maybe... In my city in kardla there are crater too,it's bit visible on surface

@robbutler2095

2 ай бұрын

@@Seliotka Indeed - but your Estonian examples somewhat younger than the Stac Fada stuff!

digby net nova scotia other part of scotland part of africa perhapsother part of an impact crater

There is always an English person telling you what do to in Scotland. This has destroyed our ancient language and culture. English is not the native language of Scotland. It is the language of occupation and misery. I refer you to the Cheviot, The Stag and the Black, Black Oil.

@robbutler2095

Жыл бұрын

???

@IWontBuy-RP

11 ай бұрын

Im not sure how that is related, or even relevant. This person is showing you geological history of your country, with examples. I would be honored if I were you, you now know how to read your part of the earth and can even envision what it would’ve been like in the past, in great detail. Don’t be so dreary, it’s a “new” world. We share our beautiful sites with each other, we’re no longer at war and probably never will be again! (And thats coming from a Dutch person, a people who were at war with the English constantly lol.)