Rise and Fall of the Mountains at Mission Trails Regional Park
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- เผยแพร่เมื่อ 29 ก.ย. 2024
- Geologist Patrick Abbott, professor emeritus at San Diego State University, explorer, guide, and author of several books including "Geology of Mission Trails Regional Park", takes viewers on a geological tour of the park. Learn about how geologic events that took place millions of years ago shaped Mission Trails and caused the rise and fall of the park’s mountains, enjoyed today by scores of San Diego County residents and visitors.
"Rise and Fall of the Mountains at Mission Trails Regional Park" was produced by the Mission Trails Regional Park Foundation and De Facto Fiction Films, and supported with funding from the City of San Diego, San Diego Association of Geologists, and additional donors to the MTRP Foundation.
In addition to this film being on the MTRP Foundation's TH-cam channel, it is available to view, free of charge, at the Mission Trails Regional Park Visitor and Interpretive Center.
Pat was my Sedimentology and Lithostratigraphy instructor at San Diego State back in the day. His field instruction was a lot like what you see here. Super interesting but man you had to stay on your toes. . . I still remember very clearly coming into the lab at 2 AM to take pipette samples for a Seds report. Sorry to veer off-subject but you know--memories, hah?
Such a great park!
Best geo overview of SD I have ever seen, thanks Patrick Abbott and team, well done!!!
Started rock climing at Mission Gorge in 1980, no park, just a worn 2 lane paved road with quarry trucks speeding and small dirt turn offs. Climbing trails were just slightly improved, wild and fun, parties on the river by Pink boulder directly at.the bottom of Main Cliff Trail.
You could stay all night sleeping by the river. Very controlled today..lol
MTRP is truly one of San Diego's crown jewels. Well done!
3:15 this is patently incorrect and is not how or why subduction-related arc volcanism occurs. In fact, subducting slabs are among the _coldest_ places in the earth’s mantle, much colder than the asthenospheric mantle wedge above it and the upper mantle below it. Arc volcanism occurs not because of heat alone and melting of the slab (although in certain conditions, slabs can melt, and this produces very specific, unique, and rare composition magmas), but rather because the subducting slab is both laden with prodigious quantities of volatile compounds such as water and carbon dioxide, as well as many rocks that have been altered by percolating seawater over millions of years, exacerbated by bending and faulting of the slab during subduction, which allows greater penetration of seawater and alteration of the oceanic crust, and these volatiles and altered oceanic crust, when it reaches a certain depth in the mantle, are subject to high pressures and temperatures that cause the rocks and minerals at this depth to change phase and undergo dehydration reactions and devolatiliztion reactions, wherein the volatile compounds soaked up by the rocks during their time under the ocean flood are released into the mantle wedge above, and the minerals left behind change phase into anhydrous forms/minerals. These volatiles that are released form supercritical fluids under high temperature and pressure that are far less dense than the rock around them, and they travel upward towards the surface, percolating through the rocks and through veins and faults in the rocks, ultimately into the hot wedge of mantle asthenosphere that overlies the subducting slab. Now, the mantle is normally solid (super-solidus) and can only be invited to melt by either keeping its temperature high while releasing confining pressure on it, moving its adiabat and causing the rock to change phase from solid to liquid (super-solidus to sub-solidus), by raising its temperature such that the rock reaches its melting point (which is much less likely), or by changing the melting point of the mantle rock at the existing temperature and pressure through other means. The devolatilization of the subducting slab and introduction of volatiles into the hot mantle wedge above it does exactly this-the addition of volatiles like water and carbon dioxide cause the melting point of mantle rock to be lowered significantly, in exactly the same way that salt on a sidewalk during winter changes the melting point of water and prevents it from freezing and forming ice. This process is called “flux melting”, and it is the only reason volcanism occurs with subduction (though there are some rare subduction-adjacent processes that also cause melting that I will not get into in detail here), and the only reason volcanism and melting _can_ occur in what is otherwise one of the coldest parts of the earth’s lithosphere. The inclusion of these volatiles has major ramifications for the kinds of magmas that form in volcanic arcs and ultimately the kinds/styles of eruptions (highly explosive), the geomorphic character of arc volcanoes (composite, cone-shaped, or calderas), and the kinds of deposits and character of their compositions that they leave behind (repeated, silicic and intermediate, volatile-rich ash-fall and ash-flow tuffs and ignimbrites and intermediate lavas).
Wrong.
Such fascinating piece of history about San Diego. Films like this definitely make me more appreciative to call San Diego home.
Brooooo. I went there in real life and we saw a snake
Lovely video! I can't wait for the park to reopen. I went from a beach loving surfer to a hiking enthusiast because if this park. Best of both worlds available to us living in San Diego.
I love this video. I lived in Santee close to Mission Trails for 25 years. I brought my kids here, and we watched the visitors center being built. I thought of Mission Trails as my sanctuary, a place that I could go to get away from the world. Thanks for this video❤😊
That was the clearest explanation of why we have the mountains and rocks that I have ever heard. Thanks for making it known to us, Julie.
This video was incredible and really well made
Dr. Pat Abbott - you have given another fantastic visualization of our own geological history to San Diego citizens. I appreciate your work in educating San Diegans. It is your work specifically in the area of Mission Trails Geology that got me hooked and if anyone is interested in diving deeper into this... Dr. Abbott wrote a book "The Geology of Mission Trails" that is sold exclusive that its visitor center. So very glad to see it visualized here in video format.
Wow i love it i saw vocano it was 40 years ago
An excellent video and exactly what I was looking for. There is an excellent companion book "The Rise and Fall of San Diego" that is worth the read. Thank you Prof. Abbott for helping to create this presentation.
Really made me appreciate what’s in my back yard so much more here in La Mesa!
This is very cool shit to learn about. I love Mission Trails.
I love hiking and mountain biking at Mission Trails, very informative.
Wooow! That was so incredibly interesting. I have lived in San Diego now for 11 years and I had no idea about all of that. I love Mission Trails Park; it's one of my favorite places in entire San Diego and now I will look at all these mountains and rocks from a very different angle. Thank you for that!!
Glad you enjoyed it!
fascinating i could watch this stuff all day long i could learn so much from you thanks for sharing
Been running mission trails almost 30yrs Loved the info! so interesting!
great work!
With the new guidelines out today will mission trails open for hiking? I live blocks away and have been itching to go
Sorry, the park is still closed until further notice.
And two weeks later the park is partially opening. The mountain trails will still be closed but apparently the service roads will be available.
Parking lots will still be closed, so biking and walking are your only access.
The Visitor Center and its parking lot are still closed, but you can hike the trails. Bushy Hill parking lot at the east end of the park is also open.
Wow that is amazing!!! Glad I came across this video, lots of great info. I've always enjoyed navigating the trails there. Now after watching; every trip will be eye opening.
Looking forward to getting back on the trails where I will have a new understanding of how this lovely area was created. Thank you for this informational video!
Thank you guys it’s amazing! It’s my favorite place in SD.
This was lovely and educational, thank you
Nicely done! Thanks!
fascinating!