Raising eclogites - reconstructing the Alpine subduction channel

[@mehrzadm8899]

You are appreciated worldwide.

[@juliamadelin3825]

Wish i had appreciated the geology when i actually lived in Turin and them Milan. Spent so much time in the mountains. Long time ago and only got the geology bug 20 years ago. Thank you so much

[@WillArtie]

Amazing. Rocks coming back up the subduction zone is something I have never heard of or considered.

[@emarekica]

This si simply fantastic! Thank you!

[@amacuro]

Fascinating stuff. This subduction return flow is a subject I'd like to learn more about. I like how it beautifully explains the high grade metamorphism observed so high up in the crust now days.

[@mji1967]

Lovely presentation, thank you

[@eyobabebe1101]

I'm grateful for your hard work! I'd be thrilled if you could add a video about the structures and metamorphism, specifically, of Island-arc volcanics (and accretionary prism).

[@HermannCortez]

What a fascinating geological story. Subuction diapirism

[@glennmorrissey5309]

Great work, thank you!

[@maxontani7986]

God bless subduction for cooking the beatiful jadeites we have here around Monviso.

[@lundysden6781]

Great overview!

[@HamzehRezaei-dp7sc]

Thank you

[@vicmadrid141]

Excellent presentation with spectacular alpine scenery & geologic structures. It is a bit paradoxical that "buoyancy forces" are responsible for raising Eclogite, which is denser than the surrounding mantle at 100 kilometers depth in a subduction zone, to levels 4,000 meters above sea level.

[@robbutler2095]

That's a good point, mafic eclogites are indeed denser than upper mantle - but it depends on what else they're embedded with... serpentinites... sedimentary rocks or riding on top of (granitic) continental crust...

[@vicmadrid141]

@@robbutler2095 On the northern California coast, Eclogite is found in the Franciscan Subduction Complex as exotic blocks in shale- , sandstone- & serpentinite-matrix mélanges. One of the many hypotheses for Exotic Block exhumation mechanisms involves the subduction of an oceanic spreading center.

[@adamc1966]

Lots of rock structures like these in California along the Smartville complex.

[@markwalton3706]

Rob, very enjoyable little series with a lot of information to digest. Couple of queries for me: (a) The diagram you 'suggest' for the original distribution (pre-subduction) of Monte Rosa, Combin & Zermatt-Saas - how then does the Monte Rosa get subducted ahead of the Combin? Does the Combin get emplaced into the accretionary wedge and then get subducted/ buried collisionally after Monte Rosa? (b) In terms of western US flat-slab subduction could the strongly bonded subducted material remain bonded and bouyant and simply force the descending Farallon plate to not descend and 'attach' itself to the base of the NA crust? Have enjoyed a lot of your YT vids especially the areas I did some of my mapping (Skye) and field training (Tryfan) on. Thanks

[@robbutler2095]

Thanks for the questions. The Combin for me stays relatively shallow and MR subducts beneath it before coming back up.. as in the rather simple animation (c 28.30).. AS for western US - can't really say, except that bonded buoyant crust is the conventional view for clogging subduction zones during continental collision...

[@paulebberson4884]

All part of the planet sorting itself into layers with the heaviest at the bottom and lightest at the top. I wonder if mantle plumes fit into this somewhere - in the big picture (not in the Alps!)

[@robbutler2095]

as you say, not this topic.... but the Earth is dynamic, a heat engine - so convection in various forms plays a key part - subduction being one, plumes another...

[@ronaldderooij1774]

Impressive, too complicated for my brain/knowledge, but still....