Helping humankind live with the earth not against it

Category: geology (Page 1 of 2)

Borealis Meditation – S04E12 IAmA Scientist and Witch AMA

Listen to the episode here:

In this episode I answer questions from both the reddit /r/SASSWitches and from submitted from listeners. The episode starts with a bit of an overview of working in academic research to give a bit more context to why my job is. I hope you enjoy and I am always open to answer any questions.

I brought up one of my favorite historical geologists Nicholas Steno

My husband also sent me this comic called “How people in science see each other” I have excerpted it here but it links to the full version.

Just replace technician with research staff….

The book I recommended for getting into witchcraft is Paganism for Beginners: The Complete Guide to Nature-Based Spirituality for Every New Seeker by Althaea Sebastiani. I highly recommend this book and this author for everyone especially those new to this path.

The other book I mentioned was Venus and Aphrodite by Bettany Hughes which I listened to on Audible.

Music in this episode is used by permission of the artists

Borealis Meditation – S04E10 What is the difference between a crystal, mineral, rock and gemstone?

List to the episode here:

Show notes: 

Music included in episode
Fold of Evening by Aazav
Iron from Stone by Damh the Bard

Here are some of the definitions we discussed and links to the quotes I used for each section.

Element:
Elements are atoms, the smallest piece that we can split matter into (except for subatomic particles and other things that we’ll leave to the physicists). Different elements have different properties. Take two different elements: iron and helium. Iron is very different than helium. You wouldn’t fill a balloon with iron any more than you would try to build a bridge out of helium. (ASU)

A solid can be made of a single element, and as we will see that is not a mineral. The elements that are known are all listed in the Periodic table. They have different properties and are defined based on the number of protons and electrons. Periodic Table

Mineral:
Minerals are materials that meet five requirements. They are:
1. naturally occurring,
2. inorganic,
3. solids,
4. with a definite chemical composition, and,
5. an ordered internal structure

(geology.com)

or from mindat.org an “informal but practical definition”
A mineral is a chemical element or compound that:
1. has a more-or-less constant composition.
2. is usually a solid with an ordered three dimensional array of ions and molecules in its crystal structure.
3. is formed by natural geologic processes and without human or other biologic intervention.
4. is not a mixture of two or more blended substances.

(mindat.org)

The ordered internal structure is also called the “Crystal Structure”

Crystal structure is a continuous ordered arrangement of one or more elements. This is simply a fancy way of saying that minerals are composed of elements that are stacked in an orderly and neat fashion. You can think of elements as different sized marbles (except, in this case, the marbles are all very, very tiny!). Based on the relative sizes of the marbles, they can be stacked in different ways […].

A good example of a simple mineral is table salt (Yes, salt is a mineral.). The proper mineral name for table salt is halite, and a geologist will often identify it by tasting it. Salt is composed of two elements; Sodium (Na) and Chlorine (Cl). Sodium and chlorine are strongly attracted to each other and stack together into a cubic crystal structure (see figure). Individual salt (halite) crystals have a cubic shape to them, which is mimicking the way that the individual elements are stacking together. Even though the elements are much too small to be able to see with your eyes (or even most microscopes), you can tell how they are stacking together by looking at the shape of the salt crystals
.”
(ASU)

“Most importantly, [a mineral is something that] has been exhaustively studied and characterized by mineralogists, declared unique in its composition and structure, and the original specimen(s) that was studied deposited for preservation in a professionally curated museum.” (mindat.org)

Resources:
MinDat
WedMineral

Mineraloid:
“A mineraloid meets almost all of the criteria of a mineral except the organized structure. Some can also lack the definite chemical composition. Minerals as we talked about are “crystalline” meaning they have an organized structure. Because mineraloids are “amorphis” they do not have an order structure.  I think this is better explained with examples. Opal, obsidian, pele’s hair, and tektites are all mineraloids. Now the last few are types of natural glasses where because of the heat and the quick cooling no crystals are able to form.” (Geology.com)

There is some controversy if organic materials can also be included. Remember that part of the definition of a mineral was that it was non-organic. This means some people include things like amber and jet as a mineraloid and others don’t. Jet is a type of coal which is made from plant material like leaves and amber is from plant resin. Also there are materials that are made in the deep ocean from the “ooze” made up of tiny organisms like diatoms and radiolarians shells called diatomite and radiolarite. For our sake I think we should also consider these mineraloids since they also lack an organized structure. 

So in that case a mineraloid is a solid, naturally occurring material without a defined interior structure and may or may not have a defined chemical composition, generally inorganic but some organic materials can also be included.

Anthropogenic substances:
“Anthropogenic substances are those produced by humans. They are not minerals. Crystals grown in a laboratory (or someone’s basement) or in laboratory or industrial furnace or retort are not minerals. Any crystals that are found on or in any man-made object are not a mineral.” (mindat.org)

Rocks:
“A rock is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition and the way in which it is formed. Rocks are usually grouped into three main groups: igneous rocks, metamorphic rocks and sedimentary rocks.” (wikipedia)

“A rock is not a mineral, nor is a mineral a rock. However, the components of a rock are minerals. Most types of rock have multiple minerals, a few have only one. Single mineral rocks are termed monomineralic rock.” (mindat)

Igneous Rocks:
An igneous rock starts out purely as a melt. Everything is liquid and all the elements are there swimming around. Then it starts to nucleate minerals, some start growing before others and use up all the elements they want. It can either cool slowly and all the crystals will grow into an interlocking solid material like a granite, or can be brought to the surface and erupt and cool quicker with some small crystals and the melt freezing not having totally formed crystals. Obsidian is the extreme of this where basically no crystals have had time to form and the melt is just frozen. Of course it is a little more complicated but we can go into that another time.

Sedimentary Rocks:
Sedimentary rocks are formed when the rocks at the surface break down either physically by breaking apart into smaller pieces or chemically. These small bits can be redeposited and smoshed and get cemented together and this forms our sedimentary rocks. Generally speaking when a rock physically breaks apart you can end up with either pieces with several minerals, or a single crystal and anywhere in between.

Metamorphic Rocks:
Metamorphic rocks can be formed from either sedimentary or igneous rocks. These are rocks where the original rock is subjected to higher levels of pressure and temperature and the minerals can start to change into other minerals. This can happen to a small or large degree and rocks can also start to flow and make cool patterns. Then this smooshed and heated rock is brought back to the surface for us to marvel at. The minerals in the original rock can change their composition and/or structure at these different conditions so one rock can be turned into multiple different types depending on how much pressure and temperature it experienced. Some minerals are only formed through this process.

Crystals/Gems:
Safety information: gem society

“A crystal is a regular polyhedral form, bounded by planes, which is assumed by a chemical element or compound, under the action of its intermolecular forces, which passing, under suitable conditions, from the state of a liquid or gas to that of a solid. A crystal is characterized first by its definite internal molecular structure and second, by its external form.” (mindat)

From merriam-webster:
1. a clear, transparent mineral or glass resembling ice.
2. the transparent form of crystallized quartz.

“A crystal consists of matter that is formed from an ordered arrangement of atoms, molecules, or ions. The lattice that forms extends out in three dimensions. Because there are repeated units, crystals have recognizable structures. Large crystals display flat regions (faces) and well-defined angles. Crystals with obvious flat faces are called euhedral crystals, while those lacking defined faces are called anhedral crystals. Crystals consisting of ordered arrays of atoms that aren’t always periodic are called quasicrystals. The word “crystal” comes from the Ancient Greek word krustallos, which means both “rock crystal” and “ice.” The scientific study of crystals is called crystallography. “ (thought co)

So then what is a gem? 
“A gem is a rare mineral that is prized and used in jewelry.” (differencebetween.net)

“difference between gem and crystal is that gem is a precious stone, usually of substantial monetary value or prized for its beauty or shine while crystal is (countable) a solid composed of an array of atoms or molecules possessing long-range order and arranged in a pattern which is periodic in three dimensions.” (WikiDiff)

“A gemstone is a crystalline mineral that can be cut and polished to make jewelry and other ornaments. The ancient Greeks made a distinction between precious and semiprecious gems, which is still used. Precious stones were hard, rare, and valuable. The only “precious” gemstones are diamond, ruby, sapphire, and emerald. All other quality stones are called “semiprecious,” even though they may not be any less valuable or beautiful.” (ThoughtCo)

I will be making a formatted reference post shortly as a quick guide. Let me know if you have any questions!


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:

Timefulness

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
http://blue.utb.edu/paullgj/physci1417/Lectures/Plate_Tectonics.html
http://www.sciencedirect.com/science/article/pii/S0012821X08005529
http://www.soest.hawaii.edu/pibhmc/pibhmc_cnmi.htm
Pagan Island Wikipedia page
Mariana Trench Wikipedia page
Volcanic Arc Wikipedia page 

Borealis Meditation – Episode 3

Listen to Episode 3 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 )

Ramblings:
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!

Geo-news:
– 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!

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