Helping humankind live with the earth not against it

Category: geology

Borealis Meditation – S04E09 Deep Time

Welcome to a conversation about the concept of Deep Time. Deep time is basically geologic time but the concept is so much more complex when trying to internalize.

I hope the many examples and repetitions help you start to understand this concept and how it can be beneficently within your practice.

I would love to continue the conversion in the comments or on twitter @katborealis

I have several recommendations for reading and listening:


This is the book I recommended on the topic of Deep Time. The first part is one of those books where when you are reading it you feel like “I wish I had written this!”

Timefulness: How thinking like a geologist can help save the world by Marcia Bjornerud

Dan Carlin

I have been listening to Dan Carlin for YEARS like… more than I want to say because it makes me feel old. He is super into the human experience in the past. His recent book has an excellent chapter on pandemics and his has an old episode on the topic as well. 

Dr. Robin Wall Kimmerer

I don’t know what to say other than I LOVE her!

I don’t know what to say about this book other than I just love love love this book! My copy has so many underlines. This is where I got the accelerating climactic chaos! Much better than Climate Change.

Braiding Sweetgrass: Indigenous wisdom, scientific knowledge, and the teachings of plants By Robin Wall Kimmerer

John McPhee

John McPhee is Mr Geology writing I think is fair to say. He is amazing to read but not a page turner. I have a few recommendations:

This was a very influential book for me. The topic of this one is humans vs. nature. Humans trying to control the uncontrollable.

John McPhee’s The Control of Nature

Pagan Island, getting to know you….

There was no activity reported for Pagan Volcano this week, so we are going to look at the island itself this week. I think Its an excellent example of an island arc volcano. 
This is a diagram of an island volcanic arc. See? We are back to the structure of the earth, like I said its always important. In order to produce an island volcanic arc, you will have an oceanic/oceanic subduction zone. The oceanic crust that is subducted is the older thicker and denser of the two oceanic plates. 
Once the older oceanic crust is subducted to around 100km the water will be driven out of the rocks and lower the melting temperature of the surrounding mantle. That is the 101 explanation of what is going on and is pretty accurate. This produces melt that becomes buoyant and rises. When this magma breaks through to the ocean floor it starts to build volcanoes. 
Once these volcanoes start to build they produce underwater eruptions until they have built up enough mass to break the ocean surface. Then it starts to build islands. These islands are volcanic arcs. 
That is how Pagan Volcano was built. 

As you can see Pagan Island is part of a chain of volcanic arc islands that sit above the subducting Pacific plate as it dives under the Philippine Sea Plate. The Mariana trench is also home to the deepest point on the earth the Challenger Deep. It is 10,898 m (35,755 ft) to 10,916 m (35,814 ft) below sea level. 
Here is Pagan Island rising from the seafloor with a vertical exaggeration of 3
Next time we will talk about the island itself and how it formed! 

References, more reading and image sources
Pagan Island Wikipedia page
Mariana Trench Wikipedia page
Volcanic Arc Wikipedia page 

Episode 3

Episode 3
download here

Show Notes:
Geo 101 section:
– Earths structure, compositional boundaries, rheology boundaries and using seismology to figure it all out!

Ray paths of EQs through the earth note the bending in the outer core and the way it creates a gap on the surface that is the P-wave shadow!

Travel time curve poster from IRIS (group of seismology organizations) the colored dots are arrivals time is on the vertical axis and degree distance is on the horizontal axis.

Feature Mineral:
– crystal systems
– quartz (general)
(blog posts are here and here )

old ass rock article
pristine mantle from earths formation!
BBC and MSNBC articles
weekly update
The secret to life may be as simple as what happens between the sheets — mica sheets

detailed notes will be available in the next few days so check back!

Chile earthquake uplift and Diamonds!

– photos of the uplifted coastline from the earthquake in Chile.

“Earlier this year, the 8.8 quake that hit Chile did more than level homes. It raised the ocean floor so much that undersea regions broke the surface of the water. Here are pictures of Chile’s incredible new coastline.”

subduction zones when locked can deform the overriding plate and when the stress is released the plate “slaps” back down, and other places rise up. depends on where in the bulge you are! there are drowned forest on the coast of Washington from the last release in the Juan de Fuca subduction zone, that area dropped enough for salt water to get into the roots and kill the tress. Same thing happened in the ’64 quake in Alaska. However its not all dropping. closer in you can get uplift. Think of it this way, if you take a ruler and push down on one end, you get a depression but a little further back it buckles up into a hump. so when that stress is released part goes up (back to original position) and part goes down (back to original position). These coastlines in Chile went up! I hope that made sense. Its the same physics in both cases the uplift and down dropping.

– Map for aspiring diamond hunters!
for articles about the research click here and here
I saw this talk at a conference last year!

though not mentioned much in the write ups on this study I believe that, this study is looking at a low velocity zone in the earth and inferring that the edges of these large low velocity zones are where you get mantle plumes, and that in order to get diamonds on the surface you need something like a mantle plume to punch through the whole crust and bring them up. On the next podcast I am going to talk about earth structure and a little bit about seismology and how it was used to determine earths structure. the map is a map of % changes in velocities of seismic waves (how we map things we can’t see) I am pretty sure there was something on this in one of my other podcasts I listen to so I’ll find it and post a link below!

Nature podcast episode its the first story! clicking should download the episode if not
its the July 15, 2010 episode

cool news find

Wooden “Stonehenge” Emerges From Prehistoric Ohio

Timber circles, like U.K. monument, aligned to summer solstice, study reveals.

Just northeast of Cincinnati, Ohio, a sort of wooden Stonehenge is slowly emerging as archaeologists unearth increasing evidence of a 2,000-year-old ceremonial site.

Among their latest finds: Like Stonehenge, the Ohio timber circles were likely used to mark astronomical events such as the summer solstice.

Formally called Moorehead Circle but nicknamed “Woodhenge” by non-archaeologists, the site was once a leafless forest of wooden posts. Laid out in a peculiar pattern of concentric, but incomplete, rings, the site is about 200 feet (57 meters) wide. (See a picture of reconstructed timber circles near Stonehenge.)

Today only rock-filled postholes remain, surrounded by the enigmatic earthworks of Fort Ancient State Memorial (map). Some are thousands of feet long and all were built by Indians of the pre-agricultural Hopewell culture, the dominant culture in midwestern and eastern North America from about A.D. 1 to 900.

read more

more rocks that I gots!

Yes I went somewhere beautiful last weekend! I drove up the Glenn Hwy to hunt for fossils in a friends field area. He has a dinosaur he is studying and we went to help find fossils to constrain the age of the deposit. So, long story short the really awesome ones now belong to our museum but will forever have my initials attached to them!
ammonite fossil

Geologist and her fossil

I spy a fossil!

Thinking about rocks

Thinking about rocks

I am surrounded by them, all the time. I do use them a lot in my magical practice so I took the time to think about the ones on my alter and what I use them to represent. And turns out, mostly its where I found them and how they formed.

I have river cobles and beach stones that have been warn smooth by the water, and that’s what I associate them with, the power of water. I also have bits of coral and shells and a crab shell that I found on the beach (note: if it’s a shell that say a hermit crab could use for a home I usually leave them, I like weathered bits of shells more then whole ones)

Lava! I have a lot of different volcanoes, I have ash from Mt Redoubt, rocks from Hawaii (I have an opinion about that curse… and some inside information I’ll tell you if you ask me 😉 ) some from Mt St Helens area, and a few other places (obsidian from Nevada….) This I associate with fire, and power and magma! Again back to how it formed, most of them violently!

I have large calcite crystals that precipitated from water, cool other rocks, that formed in a variety of ways, meta-sediments, sediments, fossils, to me these are earth, the constant recycling of material on the surface, brings to mind the cycle of explosions of life and mass extinction, and the rock cycle.

I don’t have rocks that mean air to me right now, but if I got my hand on some wind carved sandstone or nice dune cross beds, those rocks would be air to me and the power of the wind.

I guess what I am trying to say is that I have always felt that the energies in stones come more from how they were formed, or eroded then what their chemical make up is. I’ll try and come up with some good GEO 101 info on different rock forming environments. I tend to think they are pretty damn cool, but then I am a geologist

Oh and I am going fossil hunting this weekend! EEEEE so exciting!

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