Tuesday, March 12, 2019

Dr. Heidi Stauffer and Geology

It was an absolute pleasure to have Dr. Heidi Stauffer on the show to talk about her area of expertise, Geology. Our thought was initially that geology was underused in genre, but she had the insight that it can be overwhelming for people, and they don't often want to take that dive.

If you're really wanting to go deep into geologically grounding a story, Heidi recommends you start at the solar system level, at least for hard science fiction. It's fine also to start at the planet level. Many people make the mistake of having an entire planet have the same climate. Remember, even frozen planets differ at the poles and the equator. If you are working with fantasy, it's fine to start at the continent level. If your people have a concept of the whole world, it's a good idea to think about the planet. If your people think at the level of the country or kingdom, then the continent level is fine.

You have more control the closer in you go.

There is no problem with using known Earth climates. They would be statistically likely given the size of our universe, and the possibility of other universes!

Heidi was asked whether it works to say that on Titan, water ice is like bedrock. She explained that many people struggle with the concept that hydrocarbon liquid can behave like water. Titan is missing free oxygen. Earth's free oxygen came from life. If you want free oxygen on another planet, you must find a way to put it there. In fact, it's not great for living things, because it's highly corrosive. It caused one of Earth's mass extinctions.

You can look at atomic structure similarity if you try to hypothesized silicon-based life. It will however be "life unlike we've ever known."

Chemistry is important to apply to worlds. So are biology, ecology, math, etc.

Heidi's Ph.D. is in climate modeling, but she did traditional geology for her Bachelor's and Master's degrees.

Consider the scale you are working on, temporally and physically.

Heidi told us she TA'd the natural history of dinosaurs, which allowed her to teach people about body size vs. metabolism vs. gravity. These are a set of calculations that work one way for our planet, but would have to be recalculated on another planet. Big insects can only exist on high oxygen planets. A lot of paleo-botany hasn't been done, and we don't necessarily know what plants dinosaurs ate, which leaves us making educated guesses based on their physiological needs and the general features of the climate.

Small changes in a planetary/geologic system can have a domino effect.

You don't have to choose between science and story. Both are important. If you want to tweak the story science, you must do so plausibly. A hot planet can still have frozen water depending on its orbit.

The snowball Earth phenomenon had partly to do with planetary configuration and the life cycle of the star. Our sun was 25% dimmer at that point. In fiction, you could knock a planet a bit out of orbit, and when everything aligns, you get a heavy glacial episode.

Think about how to link the geology to the lives of your characters. What are the seasons like? This grows out of orbit speed and planetary angle. For example, what are things like on Mars? What would happen if it were 50% bigger? What if there were one less planet? Maybe there might be a planet where the asteroids are.

Start with known, established things, and work from there.

What if Venus orbited Earth? Venus right now is too hot and too corrosive, and our instruments dissolve before they can measure much. What if it were cooler? It did have plate tectonics once.

Kate remarked that Tatooine would have weird tides if it had two suns.

Heidi suggested that we look at the moons of Saturn and Jupiter for complex tidal effects.

If you put a civilization on a rocky moon around a gas giant, how would you see daylight? When might it be blocked by the planet?

Heidi suggests the NASA websites, the NOAA website, and the US Geological Survey for research purposes. RealClimate.org is a good source where people deal with controversies and new research about climate. The Intergovernmental panel on Climate has summaries written for non-scientists.

PBS Learning Media website is a place where you can search by subject and grade level.

Think about maps and plate tectonics. Earth has layers that differ in density and rock type. The asthenosphere has a texture like silly putty: it's solid in the short term, but liquid in the long term. The rock plates rest on this. They are not like continents in an ocean, but like broken ice on a pond, all of them moving at once. They can move relative to each other in three ways:

1. Pulling away from each other.
2. Crashing into each other. When two plates collide, the one that is denser (the oceanic plate) is forced under.
3. Sliding past each other. This is called a transform fault.

Mountains are generally formed by number 2. This is how the Himalayas were formed. Number 1 forms ocean ridges, a mountain range on the abyssal plain.

These movements can change over time. The "young" coast ranges in the US were formed when the pate boundary was subduction rather than transform. Mid-continent mountain ranges can exist but usually are old and blunt.

A downgoing oceanic plate gets melted as it goes further down. The melted rock can rise up as volcanoes.

The Himalayas were formed when the Indian subcontinent broke off of Gondwana and slammed into the Asian continent. They are still rising. There are marine fossils on top of them! A spreading ridge by Antarctica causes this. New mountain ranges are high and sharp. Weathering will slowly wear it down like the Appalachians. The Hawaii emperor seamount chain is considered to be caused by a hotspot. We assume the hotspot to be stationary with the plate moving over it (otherwise the math is a nightmare). In Yellowstone, magma keeps pushing up.

In a possible twist, there may be the equivalent of mountain chains pointing toward the core of the earth.

Volcanic eruptions lead to increased sulfur and carbon dioxide in the atmosphere.

Lake Nyos in Cameroon is a crater lake with a volcano underneath. Carbon dioxide built up under the surface of the lake, and then the lake water overturned and the carbon dioxide flowed out into the surrounding area, wiping out every living thing including people in local villages.

The Long Valley Caldera by Mammoth mountain east of the Sierra Nevada has been monitored for decades. The idea for the terrorism alert level colors come from the volcano alert levels. They monitor carbon dioxide, ground motion, and earthquakes. A caldera forms when magma empties out of an area and the ground collapses.

Heidi recommends the movie/docudrama Supervolcano from BBC/Discovery channel. It can be found on Netflix and YouTube. (Not the one made by others).

Methane clathrates are substances where methane is enclosed in a crystalline structure with water. They contributed to the Permian extinction. An eruption of basalt that lasted for a million years filled a basin of sulfur deposits, releasing toxic gas and warming Earth, which was further contributed to by methane clathrates.

Geology is very relevant to daily life. It affects how your house is built, and where, and what you need to withstand shaking. Heidi has worked with natural hazard disclosure which includes things like how close you are to a fault, how likely the ground is to undergo liquefaction, whether you are in a flood zone, or in a dam break flood zone.

Thank you so much, Dr. Heidi Stauffer, for joining us! We had such a great time and continue to be curious about the effects of geology in daily life, so I hope we can have you back on the show very soon.

Today at 4pm Pacific Daylight Time, we will be joined on the show by guest author Vida Cruz! I hope you can be there.

Don't forget, if you like the blog and the show, you can come support me and get extra worldbuilding goodies like links and topic prompts at my Patreon, here.


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