This last summer I went to that exact spot with a magnet on a string and not only didn't find the hammer.... but my sunglasses fell off my head down an adjacent crack as well. 🤣 Glad you got the hammer.
Is there another professor in geology who loves their work more than Nick Zentner? This ain't "work" for him. It's fun. It's a blast. SO fun that he wants to involve everyone in it. That's the secret to understanding the difference between a good (insert profession here) and a GREAT one. I'm thankful to have found Nick on YT years ago as I was digging around for answers to my geological questions. It's been a trip -- a FUN trip. And there's nothing more fun than learning from the best - partly because we're all learning right beside Nick. He's sharing his journey with his students and other interested people. It's a privilege, gotta thank you, Nick, for bringing us along with you.
I totally agree and have the same experience. I just found out about his work 2 years after you. I got at least 2 years worth of videos to catch up on! Thanks Nick!
Back when this "Delightful!" event occurred I was watching. My brain of perpetual recall would play it when I needed a laugh. Thank you for the "Rest of Story"
WOW ANDREW! WHAT A HERO!! Thanks for this sweet miracle. You've gotta come on camera sometime! Many more heroic deeds are headed your way!! You made Nick's holiday so special and ours! Thanks for the mega effort to retrieve the legendary hammer!!!
As always, one of the most interesting channels on UA-cam. Thank you Nick! At age 70, it is great to be mentally challenged on new topics, at least to this geologist who spent his time in sedimentary environments.
Mindblowing!! I am like you Nick I cannot sleep also so I often watch you at 5am in the morning. My wife hears you shouting and thinks it is me having a go at the neighbours
Thanks for another great lecture, Nick. Jeff's very cool 'Geologic Time' coffee mug, seen at 57:30, looks like a handy reference for working profs and armchair geology fans alike, so just ordered TWO of 'em from Amazon -- one for me, and one for you, Nick, as a small token of appreciation for all the extra work you put into UA-cam publishing for the benefit of us random schmoes. :)
Wow Nick way to go bringing Jeff Tepper into this discussion its paramount that he is included. these concepts are just amazing . One of the best parts of this was seeing that you got your hammer back, thank you so much kind Sir for doing that for Nick It had to have made his Christmas the best gift ever! I thought it was a gonner for sure. Basalt German Choclate Cake gave up its treasure. Nick I hope you frame it. I thought this was the most thought provoking segment ever. You are all on the cusp of being able to explaining in story how these plutons got moved so high. I am such a novice, but I am totally hooked on Geology now.
Nick there you go again, the puzzle pieces are coming together 1by1. Jeff was great this episode. Man you just keep dragging us through the weeds of geological theory. I love it!
I think I've figured out that one (ONE!) of the things that muddies the geological crystal ball is the sheer number of things going on at nearly the same time and at nearly the same place. I very much appreciate Jeff Tepper's precision of speech.
Once again from Australia, thank you for these programs. I usually struggle to fully understand a lot of the content but since I have found you on UA-cam sometime in the last 12 months, my latent interest in geology has been fired up again and I have yet another interest to work on understanding and hopefully help keep dementia at bay!
The older Estwing hammer, before the blue plastic covered steel handle, I think it was leather, I had one, can’t find it, I have several of the blue ones, the all steel design is the best. I hope it’s not too pathetic of me, but your geology lessons are the most meaningful thing in my life these days.
Thanks for another great show and great guest Nick. You have introduced us to so many interesting and committed people, and of course we feel so lucky to get to know you most of all. So happy you got your hammer back!! Tell Jeff we ordered one of those geology cups.😂
Ok I'm at work...I'm following. I feel I got it, history repeats itself ...a d my coworkers think I'm going nuts when I concur outloud. At 36:50 I'm exited. I'm almost caught up to a live show, been with you since just before a-z pandemic!! Had one class of plate tectonics in 1982. Butte JC Ca. Now electronics doesn't seem so hot. Yuma Arizona now.
Seems like Jeff was talking about two skinny slab windows? Also I live a few miles from Chimacum rock that I climbed about 35 years ago, what a treat to hear about!
Your lecture had me waking up in the night thinking about roll back, peripheral near trench magmas, spreading ridges and hot spots... fascinating stuff, Thank you for sharing.
Cool hammer and that turtle shell looks real They dry out and get preserved very well as long as they stay dry Our cats used to take the turtles out of the fish tank and play hockey with them oops One day one disappeared and we could not find it Well months went by and we cleaned up well moving the big entertainment unit and right stuck under was a very dried out turtle We kept the turtle for a long time until my oldest son needed to make an instrument at school I heard you could turn a turtle shell into a rattle So we put tacks, ball berring and a couple legos inside and put paper in there to keep the stuff off the playdough we plugged the holes with He took it to school showed the teacher and he lost it before he had to turn it in lol poor kid and the teacher said she seen it anyway so he got an A that was a very good grade for my son he was so happy
The creation of plutons from slab failure makes me think of a rock 🪨 dropping into a pond. It’s passage makes a hole in the water. Yet around the edges the water rapidly above the waters level at rest. So bloop the slab fails makes a hole 🕳 into the lithosphere…splash you got your magma popping up plutons into the crust…the suction from the slab failure pulling in material as it sinks…restarting the subduction the material from an adjacent plate filling the gap. Love the new tech…kinda nostalgic for the “Cozy Fort” ™️ and frequent guest appearances by Bijou.
In a shadow box, place a large picture of you and the film crew on the columns, and secure the old hammer in front of the photo. Don't take off or alter the patina on the hammer. Date when it was "lost", when it was "found" and by whom, and when you were reunited with it. Include a small mirror on the back of the box "wall", behind the head of the hammer with a few microscopic LED lights strategically placed inside for the viewer. Lovely story for your office wall.
45:15 KEY MOMENT. The subduction of this spreading ridge boundary believed to be centered under Siletzia initiates the subsequent near trench volcanic fireworks 50:00. Somehow I initially failed to register this specific event - it’s a monster detail that is as important as Siletzia’s docking impact. A second and critical component unique to this terrane’s arrival. This is beautifully put into perspective in “Siletzia Fireworks in the Pacific Northwest.”
1:34 Jeff left out NA WSW drift over-riding the Farallon plate and its spreading ridge (the spreading ridge did not move as his description makes it appear.) @20-25MA, the NW orientation of the continent @present day California resulted in a nearly equal subduction of the Farallon plate, as its spreading ridge was also oriented @NW linearly; however, the Farallon spreading ridge took @5 million years to subduct due to its offsets. How do I know this? The JDF spreading ridge is a witnessing remnant.
Nick, is the boulder battle with part of that's spreading ridge or is it an offshoot of Yellowstone hotspot? I really like watching your classes here Snowcat Butte Montana
During the BIG EVENT 100Ma, were two subduction zones, one eastward and one westward, coming together at the craton margin, sealing them both and leaving a structure like the West Idaho Shear Zone?
Time Stamps: 00:00 Video Starts 07:52 Schedule 09:23 Nick's Hammer 16:08 Lecture Start 19:09 Overview 20:32 North Cascade Magmatic Flare Ups 22:44 Cretaceous Plutons 24:00 Eocene Plutons 24:21 In Between Plutons 25:19 What are the similarities and differences between the three flare ups? 27:46 How are the magmas being generated? 40:11 Slab Failure Animation 41:25 North Cascades Geologic Maps and Photos 47:07 Modern Volcanic Arc 48:00 Forearc 49:17 Near Trench Magmas (NTM) 51:32 Slab Window 52:58 Jeff Tepper 56:31 NTM Examples 58:30 Slab Window vs Arc Magmas 01:00:32 Adakite 01:03:03 Chimacum Rock 01:04:26 Other Slab Window Sites 01:07:25 How to Tell NTMs apart? 01:10:57 Plichuck and Bald Mtn Results from Slab Failure 01:14:08 Magmatic Flare Up Differences 01:16:50 Q&A with Jeff 01:36:36 Q&A with Nick 01:44:15 Toast and Goodbye
Something Jeff Tepper said makes me wonder - did we have Washington and Oregon running over two segments of the spreading ridge at the same time, offset by a transform section?
Are slab windows formed only where an oblique spreading ridge is subducted, or can they also form from other conditions like when a transform step is subducted
@49:20 At 50.1 deg. N. Lat. 129.7 deg. W. Long., the Explorer spreading ridge is/has been subducting under BC for millions of years per the Queen Charlotte fault; where are the near trench magmas there and @the present Explorer trench?
feel free to use the near trench magma samples I sent you in any episodes you like, cheers. I wonder if Dr. Tepper would make anything of the high pyroxene/olivine rocks I sent you from BH.
Wouldn't the "fireworks" be occurring as either Wrangelia or Siletzia are approaching the coast and be stopped once they are docked and the subduction also stops?
@JEFF TEPPER ! Paperwork ( own works ) ! Is tempered | woven ( can be found ) in HIS STUDENTS THESIS's , jeff is the master crafter , cultivating the roots to the harvest. ?any papers produced by his students?
Wouldn't it make sense that the magmas under the crust would get hydraulically pushed up along the fault lines when the crust plummets down into it as the crustal extension happens during the Eocene? Kind of a splash action squeezing out around the edges after you drop the plug down into the fluid bath - squirting around the cork?
Things are getting a little screwy in your brain when you just read, while moving the eyes, and you see "Goldie Hahn" instead of "Golden Horn". Time to see the eye doctor!
Avana Vana Since it was inappropriate to communicate back and forth on the Live Chat, I am responding to your reply to this comment here as we agreed: My Comment: @ 50:00 "WHY IS YOUR SPREADING RIDGE ORIENTED EAST-WEST PERPENDICULAR TO SILETZIA, WHEN THE NTM’s ARE IN A PARALLEL NORTH-SOUTH PLAIN? HOW DOES YOUR OBLIQUE SPREADING RIDGE MAGMA FLOW (THE TWO ARROWS) WORK?" Your reply: "because the ridge itself migrates north and south as it subducts. Ridges perpendicular to the Margin have transform offsets to the north and south as the ridge subducts, the different ridge segments offset to the north and south come into contact with the margin and subduction zone and change the locus of magmatism." First, I see no evidence that whole Spreading Ridges (SR's) migrate, but they do shift laterally (Offsets) with their varying velocities and rates; thus, until I see it, they're stationary like Mantle Plumes. Imho, instead, SR's are subducted on one end and truncated on the other- Study the Juan De Fuca (JDF) SR as I have, it's subducting obliquely @Northern Vancouver Is., B.C., and truncating and deforming North of the Southern Gorda/Mendocino Junction. The affected area is localized in the Gorda subplate and is isolated from the JDF and Explorer subplates; therefore, Imho, the whole JDF plate does not migrate as many geologists have speculated. Second, I don't agree with creating theoretical plate boundaries ("Kula" and "Resurrection") to accommodate the latest scientific findings, with what little is known, those are rabbit holes. I presume that the Farallon and Pacific are the only plates supported by physical and tomographical evidence on the West Coast that can be reliably mapped. However, these plates had a beginning and will have an end, and others had a beginning and an end as well, but there isn’t a preponderance of facts to map them out. Imho, your explanation would be valid if there was an age progression NE-SW as the Continent sweeps over the Spreading Ridge Offsets; there should be a steady aging from the last point to the first, but this is not the case, which is why I questioned the Professor. Remember when another viewer "Bob" @ 1:26 questioned Nick and Jeff about including the Tillamook and Yachats Volcanics? (Which are @200 miles South of the WA. study formations.) Nick was surprised when Jeff included them as Near Trench Magmas (NTM's,) which blew his Perpendicular SR Subduction theory out of the water. In reality, there is no age progression, there is a random separation N-S in formation dates. (Metchosin, B.C. @52ma, Crecent, WA. @49ma, Black Hills, Greys River and Willapa Hills, WA. 51-46ma., Tillamook, OR. 54-49ma., Siletz River, OR. 54-49ma., Roseburg, OR. 56-52ma.) This is indicative of an oblique to parallel Spreading Ridge subduction similar to what the JDF is now, not Nick's perpendicular, because a single point cannot affect terrain hundreds of miles away without age progression, but oblique-parallel subduction and seamount plumes could. Chains of Seamount plumes are easily observed off the NW Coast today, they’re moving toward us and us toward them obliquely. Indeed, this would deny evidence of a "Kula" and support a Farallon plate subduction model, much simpler Imho. You didn't address Nick's oblique SR plate flow diagram @ 50:00 , in which he drew the two diagonal arrows toward the subduction zone as if oblique SR flows exist.
WHY ISN'T THE SPREADING RIDGE RUNNING PARALELL TO THE EXTENSION FIELD VECTOR? IN OTHER WORDS, HOW DO YOU GET EAST-WEST EXTENSION WHEN THE SPREADING IS ORIENTED NORTH-SOUTH? IF THE SPREADING RIDGE INTERSECTED NOT MERELY OBLIQUELY, RATHER, IF IT INTERSECTED THE CONTINENTAL MARGIN ACUTELY IT COULD HAVE AN EXTENSION VECTOR IN A MORE OR LESS EAST-WEST ORIENTATION, NO?
This last summer I went to that exact spot with a magnet on a string and not only didn't find the hammer.... but my sunglasses fell off my head down an adjacent crack as well. 🤣 Glad you got the hammer.
Is there another professor in geology who loves their work more than Nick Zentner? This ain't "work" for him. It's fun. It's a blast. SO fun that he wants to involve everyone in it. That's the secret to understanding the difference between a good (insert profession here) and a GREAT one. I'm thankful to have found Nick on YT years ago as I was digging around for answers to my geological questions. It's been a trip -- a FUN trip. And there's nothing more fun than learning from the best - partly because we're all learning right beside Nick. He's sharing his journey with his students and other interested people. It's a privilege, gotta thank you, Nick, for bringing us along with you.
I totally agree and have the same experience. I just found out about his work 2 years after you. I got at least 2 years worth of videos to catch up on! Thanks Nick!
Back when this "Delightful!" event occurred I was watching. My brain of perpetual recall would play it when I needed a laugh. Thank you for the "Rest of Story"
WOW ANDREW! WHAT A HERO!! Thanks for this sweet miracle. You've gotta come on camera sometime! Many more heroic deeds are headed your way!! You made Nick's holiday so special and ours! Thanks for the mega effort to retrieve the legendary hammer!!!
A toast to you Nick. Thank you for sharing your passion with use. I enjoy you very much.Great job as always.
What a cool story about getting your hammer back! I was smiling right along with you as you were sharing your story!
As always, one of the most interesting channels on UA-cam. Thank you Nick! At age 70, it is great to be mentally challenged on new topics, at least to this geologist who spent his time in sedimentary environments.
I like being the Audience….looking back at you. And learning amazing things.
Mindblowing!! I am like you Nick I cannot sleep also so I often watch you at 5am in the morning. My wife hears you shouting and thinks it is me having a go at the neighbours
Jeff is blowing minds up! Thank You!
Thanks for another great lecture, Nick. Jeff's very cool 'Geologic Time' coffee mug, seen at 57:30, looks like a handy reference for working profs and armchair geology fans alike, so just ordered TWO of 'em from Amazon -- one for me, and one for you, Nick, as a small token of appreciation for all the extra work you put into UA-cam publishing for the benefit of us random schmoes. :)
Wow Nick way to go bringing Jeff Tepper into this discussion its paramount that he is included. these concepts are just amazing . One of the best parts of this was seeing that you got your hammer back, thank you so much kind Sir for doing that for Nick It had to have made his Christmas the best gift ever! I thought it was a gonner for sure. Basalt German Choclate Cake gave up its treasure. Nick I hope you frame it. I thought this was the most thought provoking segment ever. You are all on the cusp of being able to explaining in story how these plutons got moved so high. I am such a novice, but I am totally hooked on Geology now.
Nick there you go again, the puzzle pieces are coming together 1by1. Jeff was great this episode. Man you just keep dragging us through the weeds of geological theory. I love it!
I think I've figured out that one (ONE!) of the things that muddies the geological crystal ball is the sheer number of things going on at nearly the same time and at nearly the same place. I very much appreciate Jeff Tepper's precision of speech.
Awesome hammer story!
Thanks, Nick! Another great lesson.
Fantastic as always Nick 👍
Thanks NIck for taking your time to teach us. Your a fantastic teacher.
I love the way that we can start an episode where not even Nick knows how it's going to end! Well, I now have a different theory...
Thank you, Nick and Jeff. How cool you got the hammer back!
Once again from Australia, thank you for these programs. I usually struggle to fully understand a lot of the content but since I have found you on UA-cam sometime in the last 12 months, my latent interest in geology has been fired up again and I have yet another interest to work on understanding and hopefully help keep dementia at bay!
The older Estwing hammer, before the blue plastic covered steel handle, I think it was leather, I had one, can’t find it, I have several of the blue ones, the all steel design is the best. I hope it’s not too pathetic of me, but your geology lessons are the most meaningful thing in my life these days.
Thanks for another great show and great guest Nick. You have introduced us to so many interesting and committed people, and of course we feel so lucky to get to know you most of all. So happy you got your hammer back!! Tell Jeff we ordered one of those geology cups.😂
Ok I'm at work...I'm following. I feel I got it, history repeats itself ...a d my coworkers think I'm going nuts when I concur outloud. At 36:50 I'm exited.
I'm almost caught up to a live show, been with you since just before a-z pandemic!! Had one class of plate tectonics in 1982. Butte JC Ca. Now electronics doesn't seem so hot. Yuma Arizona now.
Seems like Jeff was talking about two skinny slab windows? Also I live a few miles from Chimacum rock that I climbed about 35 years ago, what a treat to hear about!
Your lecture had me waking up in the night thinking about roll back, peripheral near trench magmas, spreading ridges and hot spots... fascinating stuff, Thank you for sharing.
I can't tell you how excited I am to be back in your class. Happy New Year!!
Lillian, I resemble that remark.
Cool hammer and that turtle shell looks real
They dry out and get preserved very well as long as they stay dry
Our cats used to take the turtles out of the fish tank and play hockey with them oops
One day one disappeared and we could not find it
Well months went by and we cleaned up well moving the big entertainment unit and right stuck under was a very dried out turtle
We kept the turtle for a long time until my oldest son needed to make an instrument at school
I heard you could turn a turtle shell into a rattle
So we put tacks, ball berring and a couple legos inside and put paper in there to keep the stuff off the playdough we plugged the holes with
He took it to school showed the teacher and he lost it before he had to turn it in lol poor kid and the teacher said she seen it anyway so he got an A that was a very good grade for my son he was so happy
Thank you again for making these videos. So very interesting. And you should know I even sometimes understand the whole picture. 😊
The creation of plutons from slab failure makes me think of a rock 🪨 dropping into a pond. It’s passage makes a hole in the water. Yet around the edges the water rapidly above the waters level at rest. So bloop the slab fails makes a hole 🕳 into the lithosphere…splash you got your magma popping up plutons into the crust…the suction from the slab failure pulling in material as it sinks…restarting the subduction the material from an adjacent plate filling the gap. Love the new tech…kinda nostalgic for the “Cozy Fort” ™️ and frequent guest appearances by Bijou.
Lol... I like the pep talk before he starts... it's literally a routine.... lol.... yes I'm new to his channel and catching up
Congrats, theres' a lot of joy in front of you! Have fun!
In a shadow box, place a large picture of you and the film crew on the columns, and secure the old hammer in front of the photo. Don't take off or alter the patina on the hammer. Date when it was "lost", when it was "found" and by whom, and when you were reunited with it. Include a small mirror on the back of the box "wall", behind the head of the hammer with a few microscopic LED lights strategically placed inside for the viewer. Lovely story for your office wall.
45:15 KEY MOMENT. The subduction of this spreading ridge boundary believed to be centered under Siletzia initiates the subsequent near trench volcanic fireworks 50:00.
Somehow I initially failed to register this specific event - it’s a monster detail that is as important as Siletzia’s docking impact. A second and critical component unique to this terrane’s arrival.
This is beautifully put into perspective in “Siletzia Fireworks in the Pacific Northwest.”
This forearc discussion surely has some light to shed on the Clear Lake volcanics, a funny place for a lonely little volcano.
Thank You booth for such great content!
The first thing that I would ask aliens, do you have videos of Washington for the past 200Ma?
lol
Great Job Nick!!! Looks like all that testing is paying off nicely. I'm blown away by the complexity of the PNW geology. Thanks for sharing.
Cant be there yesterday Prof watching now hope next time i may be with you while streaming Happy New Year a big hug!
Hammer!🧡
Bottoms Up Everyone. May 2022 be an improvement for all.
1:34 Jeff left out NA WSW drift over-riding the Farallon plate and its spreading ridge (the spreading ridge did not move as his description makes it appear.)
@20-25MA, the NW orientation of the continent @present day California resulted in a nearly equal subduction of the Farallon plate, as its spreading ridge was also oriented @NW linearly; however, the Farallon spreading ridge took @5 million years to subduct due to its offsets. How do I know this? The JDF spreading ridge is a witnessing remnant.
Nick, is the boulder battle with part of that's spreading ridge or is it an offshoot of Yellowstone hotspot? I really like watching your classes here
Snowcat Butte Montana
Big thanks to Andrew for getting the rock hammer back. Hope you had someone with to video it!
Do something special with the hammer like a framed screenshot of that moment, and a photo of Tom and Nick on location.
During the BIG EVENT 100Ma, were two subduction zones, one eastward and one westward, coming together at the craton margin, sealing them both and leaving a structure like the West Idaho Shear Zone?
If you ever gonna make a space travel - remember towel, if you are geologist - never loose your hammer!
Time Stamps:
00:00 Video Starts
07:52 Schedule
09:23 Nick's Hammer
16:08 Lecture Start
19:09 Overview
20:32 North Cascade Magmatic Flare Ups
22:44 Cretaceous Plutons
24:00 Eocene Plutons
24:21 In Between Plutons
25:19 What are the similarities and differences between the three flare ups?
27:46 How are the magmas being generated?
40:11 Slab Failure Animation
41:25 North Cascades Geologic Maps and Photos
47:07 Modern Volcanic Arc
48:00 Forearc
49:17 Near Trench Magmas (NTM)
51:32 Slab Window
52:58 Jeff Tepper
56:31 NTM Examples
58:30 Slab Window vs Arc Magmas
01:00:32 Adakite
01:03:03 Chimacum Rock
01:04:26 Other Slab Window Sites
01:07:25 How to Tell NTMs apart?
01:10:57 Plichuck and Bald Mtn Results from Slab Failure
01:14:08 Magmatic Flare Up Differences
01:16:50 Q&A with Jeff
01:36:36 Q&A with Nick
01:44:15 Toast and Goodbye
Great show! Could offsets be an explanation for a southern migration of the spreading ridge?
Something Jeff Tepper said makes me wonder - did we have Washington and Oregon running over two segments of the spreading ridge at the same time, offset by a transform section?
Nope. Spreading ridge was more normal to the coast than parallel to it.
Oh, that Wacky Eee-O-Seeen! Yo, Teach: be careful navigating in and on the frozen stuff, please!
Christmas Miracle!!
Hammer!
that's it, that's the comment.
@ Scott Durkin- plutons are magmas that cool beneath, never erupting.
Oh I like Tipper a lot
Are slab windows formed only where an oblique spreading ridge is subducted, or can they also form from other conditions like when a transform step is subducted
@49:20 At 50.1 deg. N. Lat. 129.7 deg. W. Long., the Explorer spreading ridge is/has been subducting under BC for millions of years per the Queen Charlotte fault; where are the near trench magmas there and @the present Explorer trench?
feel free to use the near trench magma samples I sent you in any episodes you like, cheers. I wonder if Dr. Tepper would make anything of the high pyroxene/olivine rocks I sent you from BH.
Wouldn't the "fireworks" be occurring as either Wrangelia or Siletzia are approaching the coast and be stopped once they are docked
and the subduction also stops?
@JEFF TEPPER ! Paperwork ( own works ) ! Is tempered | woven ( can be found ) in HIS STUDENTS THESIS's , jeff is the master crafter , cultivating the roots to the harvest. ?any papers produced by his students?
Trans-tensional because of the clockwise rotation? Wrenching apart from the rotation ?...
Wouldn't it make sense that the magmas under the crust would get hydraulically pushed up along the fault lines when the crust plummets down into it as the crustal extension happens during the Eocene? Kind of a splash action squeezing out around the edges after you drop the plug down into the fluid bath - squirting around the cork?
Has someone looked at the Lord Hill basalt near Monroe? This looks to be some of this near shore basalt.
Things are getting a little screwy in your brain when you just read, while moving the eyes, and you see "Goldie Hahn" instead of "Golden Horn". Time to see the eye doctor!
Thursday morning at 7:28am from zip 98338.
Understand better the differente magmas, thanks Sir Jeff
What happens to the spride ridges along the time?
Avana Vana Since it was inappropriate to communicate back and forth on the Live Chat, I am responding to your reply to this comment here as we agreed:
My Comment: @ 50:00 "WHY IS YOUR SPREADING RIDGE ORIENTED EAST-WEST PERPENDICULAR TO SILETZIA, WHEN THE NTM’s ARE IN A PARALLEL NORTH-SOUTH PLAIN? HOW DOES YOUR OBLIQUE SPREADING RIDGE MAGMA FLOW (THE TWO ARROWS) WORK?"
Your reply: "because the ridge itself migrates north and south as it subducts. Ridges perpendicular to the Margin have transform offsets to the north and south as the ridge subducts, the different ridge segments offset to the north and south come into contact with the margin and subduction zone and change the locus of magmatism."
First, I see no evidence that whole Spreading Ridges (SR's) migrate, but they do shift laterally (Offsets) with their varying velocities and rates; thus, until I see it, they're stationary like Mantle Plumes. Imho, instead, SR's are subducted on one end and truncated on the other- Study the Juan De Fuca (JDF) SR as I have, it's subducting obliquely @Northern Vancouver Is., B.C., and truncating and deforming North of the Southern Gorda/Mendocino Junction. The affected area is localized in the Gorda subplate and is isolated from the JDF and Explorer subplates; therefore, Imho, the whole JDF plate does not migrate as many geologists have speculated.
Second, I don't agree with creating theoretical plate boundaries ("Kula" and "Resurrection") to accommodate the latest scientific findings, with what little is known, those are rabbit holes. I presume that the Farallon and Pacific are the only plates supported by physical and tomographical evidence on the West Coast that can be reliably mapped. However, these plates had a beginning and will have an end, and others had a beginning and an end as well, but there isn’t a preponderance of facts to map them out.
Imho, your explanation would be valid if there was an age progression NE-SW as the Continent sweeps over the Spreading Ridge Offsets; there should be a steady aging from the last point to the first, but this is not the case, which is why I questioned the Professor. Remember when another viewer "Bob" @ 1:26 questioned Nick and Jeff about including the Tillamook and Yachats Volcanics? (Which are @200 miles South of the WA. study formations.) Nick was surprised when Jeff included them as Near Trench Magmas (NTM's,) which blew his Perpendicular SR Subduction theory out of the water.
In reality, there is no age progression, there is a random separation N-S in formation dates. (Metchosin, B.C. @52ma, Crecent, WA. @49ma, Black Hills, Greys River and Willapa Hills, WA. 51-46ma., Tillamook, OR. 54-49ma., Siletz River, OR. 54-49ma., Roseburg, OR. 56-52ma.) This is indicative of an oblique to parallel Spreading Ridge subduction similar to what the JDF is now, not Nick's perpendicular, because a single point cannot affect terrain hundreds of miles away without age progression, but oblique-parallel subduction and seamount plumes could. Chains of Seamount plumes are easily observed off the NW Coast today, they’re moving toward us and us toward them obliquely. Indeed, this would deny evidence of a "Kula" and support a Farallon plate subduction model, much simpler Imho.
You didn't address Nick's oblique SR plate flow diagram @ 50:00 , in which he drew the two diagonal arrows toward the subduction zone as if oblique SR flows exist.
PS: please never clean up the recovered rock hammer…the patina tells a great story!
WHY ISN'T THE SPREADING RIDGE RUNNING PARALELL TO THE EXTENSION FIELD VECTOR? IN OTHER WORDS, HOW DO YOU GET EAST-WEST EXTENSION WHEN THE SPREADING IS ORIENTED NORTH-SOUTH? IF THE SPREADING RIDGE INTERSECTED NOT MERELY OBLIQUELY, RATHER, IF IT INTERSECTED THE CONTINENTAL MARGIN ACUTELY IT COULD HAVE AN EXTENSION VECTOR IN A MORE OR LESS EAST-WEST ORIENTATION, NO?
a "leaky transform" step;?
I meant batholith not battle with thank you
You've hardly aged!
❤❤
snow next time it might be larva lol....
HI
P