NASA: First Geologic Map of Titan

Guest post by David Middleton

From the cooler than schist files…

NEWS | NOVEMBER 18, 2019
The First Global Geologic Map of Titan Completed

The first map showing the global geology of Saturn’s largest moon, Titan, has been completed and fully reveals a dynamic world of dunes, lakes, plains, craters and other terrains.

Titan is the only planetary body in our solar system other than Earth known to have stable liquid on its surface. But instead of water raining down from clouds and filling lakes and seas as on Earth, on Titan what rains down is methane and ethane – hydrocarbons that we think of as gases but that behave as liquids in Titan’s frigid climate.

“Titan has an active methane-based hydrologic cycle that has shaped a complex geologic landscape, making its surface one of most geologically diverse in the solar system,” said Rosaly Lopes, a planetary geologist at NASA’s Jet Propulsion Laboratory in Pasadena, California, and lead author of new research used to develop the map.

“Despite the different materials, temperatures and gravity fields between Earth and Titan, many surface features are similar between the two worlds and can be interpreted as being products of the same geologic processes. The map shows that the different geologic terrains have a clear distribution with latitude, globally, and that some terrains cover far more area than others.”

Lopes and her team, including JPL’s Michael Malaska, worked with fellow planetary geologist David Williams of the School of Earth and Space Exploration at Arizona State University in Tempe. Their findings, which include the relative age of Titan’s geologic terrains, were recently published in the journal Nature Astronomy.Lopes’ team used data from NASA’s Cassini mission, which operated between 2004 and 2017 and did more than 120 flybys of the Mercury-size moon. Specifically, they used data from Cassini’s radar imager to penetrate Titan’s opaque atmosphere of nitrogen and methane. In addition, the team used data from Cassini’s visible and infrared instruments, which were able to capture some of Titan’s larger geologic features through the methane haze.

“This study is an example of using combined datasets and instruments,” Lopes said. “Although we did not have global coverage with synthetic aperture radar [SAR], we used data from other instruments and other modes from radar to correlate characteristics of the different terrain units so we could infer what the terrains are even in areas where we don’t have SAR coverage.”

Williams worked with the JPL team to identify what geologic units on Titan could be determined using first the radar images and then to extrapolate those units to the non-radar-covered regions. To do so, he built on his experience working with radar images on NASA’s Magellan Venus orbiter and from a previous regional geologic map of Titan that he developed.

“The Cassini mission revealed that Titan is a geologically active world, where hydrocarbons like methane and ethane take the role that water has on Earth,” Williams said. “These hydrocarbons rain down on the surface, flow in streams and rivers, accumulate in lakes and seas, and evaporate into the atmosphere. It’s quite an astounding world!”

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency (ESA) and the Italian Space Agency. NASA’s JPL, a division of Caltech in Pasadena, manages the mission for NASA’s Science Mission Directorate in Washington. JPL designed, developed and assembled the Cassini orbiter. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the U.S. and several European countries.

More information about Cassini can be found here:

https://solarsystem.nasa.gov/cassini

NASA JPL

The first global geologic map of Titan is based on radar and visible-light images from NASA’s Cassini mission, which orbited Saturn from 2004 to 2017. Labels point to several of the named surface features.Credit: NASA/JPL-Caltech/ASU
› Full image and caption

The first global geologic map of Saturn’s largest moon, Titan, is based on radar and visible and infrared images from NASA’s Cassini mission, which orbited Saturn from 2004 to 2017.

Black lines mark 30 degrees of latitude and longitude. Map is in Mollweide projection, a global view that attempts to minimize the size or area distortion, especially at the poles (although shapes are increasingly distorted away from the center of the map). It is centered on 0 degrees latitude, 180 degrees longitude. Map scale is 1:20,000,000.

In the annotated figure, the map is labeled with several of the named surface features. Also located is the landing site of the European Space Agency’s (ESA) Huygens Probe, part of NASA’s Cassini mission.

The map legend colors represent the broad types of geologic units found on Titan: plains (broad, relatively flat regions), labyrinth (tectonically disrupted regions often containing fluvial channels), hummocky (hilly, with some mountains), dunes (mostly linear dunes, produced by winds in Titan’s atmosphere), craters (formed by impacts) and lakes (regions now or previously filled with liquid methane or ethane). Titan is the only planetary body in our solar system other than Earth known to have stable liquid on its surface — methane and ethane.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini.

NASA JPL

No . . . This has no relevance to how hydrocarbons formed on Earth . . . or anywhere else, other than Titan . . . Actually, it doesn’t even have any relevance to how hydrocarbons formed on Titan, in much the same manner that the fact that Earth’s lakes and oceans are mostly filled with water doesn’t tell us anything about how the water formed . . . But it is very fracking cool.

Reference

Lopes, R.M.C., Malaska, M.J., Schoenfeld, A.M. et al. A global geomorphologic map of Saturn’s moon Titan. Nat Astron (2019) doi:10.1038/s41550-019-0917-6 LINK

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NASA and ESA Celebrate 10 Years Since Titan Landing

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117 thoughts on “NASA: First Geologic Map of Titan

  1. That is one serious flat moon…or am I reading this wrong?

    If you have hydrogen near carbon you are going to get hydrocarbons. I assume this moon was once much warmer, so the reactions were likely favored. One has to wonder where the primal oxygen is at? People do not usually realize how much oxygen is with the Earth – they think free oxygen, not oxygen bound in minerals (and water).

  2. Well that’s the light hydrocarbon exploration problem solved.
    Just a matter of organising the cryogenic collection, transport and delivery process.
    Engineers wanted, must be able to work off planet on extended contracts.

      • +2. My immediate reaction too; this is more geography than geology. (As is ‘climate science’ more arts than science, being most often a division of geography.)

        But DM is right, it still is cool; not as cool to me as the images of Pluto, but cool. That’s a long way off for man to be mapping topography through a thick haze.

        But cooler than that is the understanding that Titan is active; by the next time we do it this will be all changed.

        BTW, I find the names applied to features around space just plain goofy. Xanadu??–really. All I needed to screw this up is an image of a disco-era Oblivious Neutron-Bomb.

    • Geomorphology is a subset of geology… However, you are correct. It is a landform map. Technically, a geologic map would depict the bedrock geology. They can’t make a true geologic map until someone with a Brunton compass, rock hammer, sample bag, field book, etc. goes to Titan and pokes around… But, the map is still cooler than schist.

      • The rock hammer would have to be somewhat exotic. An ordinary steel hammer would shatter the first time you took a bash with it at that temperature.

        And the samples would vaporize and quite possibly burn or explode at room temperature.

        • You just took all of the fun out of field geology on Titan… Next you’ll tell me that my Brunton compass won’t work either… 😉

        • Not that exotic. Titanium, nickle, copper all maintain structural integrity and strength well below those temperatures. What do you think we make cryogenic systems out of? Not much gets colder than liquid helium, except solid helium and that’s only a few degrees colder. Yet, we can make exotic machines out of those and other materials that will get you to Titan where, alas, you will need a different type of compass.

        • They wouldn’t burn on Titan – no free oxygen. If you brought them back to the lab for analysis, perhaps. However, we will just send a couple of robots to collect and analyze the samples. No union wages needed.

      • David,
        I’ve been fascinated with Titan forever. My dad was a petroleum Geologist, and was. too.
        Is it possible that some types of hydrocarbons on earth came from a non-biological process?
        (Not coal, obviously.) I know that we find oil and gas in porous carbonates and sandstone, but is it possible that it was formed by natural chemical processes, and just trapped by impermeable boundaries in porous ancient reefs, etc?

        • Oil & gas do form from non-biological processes. The original source material is of biological origin, but the processes of turning the organic material into kerogen and then oil & gas are not biological.

          Methane can easily be formed without any biological material. As can some heavier hydrocarbons. The Lost City Hydrothermal Vent on the Mid-Atlantic Ridge. Is an example of methane and traces of heavier hydrocarbons being formed by the Fischer-Tropsch process (most likely). It’s possible that even heavier, more complex, hydrocarbons can be formed from similar processes. It’s just that there is no evidence anywhere on Earth of a significant volume of petroleum formed from such processes. There are very few crude oil accumulations that are even consistent with the abiogenic hypotheses and no significant accumulations inconsistent with the generally accepted theory of hydrocarbon formation. One of the misconceptions held by abiogenic oil aficionados, is that geologists are somehow blinkered by a 100 year old theory. That’s nonsense. The theory was derived from the observations over 100 years of exploring for oil. The classic petroleum geology text book by Levorsen reviews a multitude of various hypotheses; then concludes that it doesn’t really matter because it wouldn’t affect the process of oil & gas exploration. “Oil is where you find it.” However it originally formed, it has to be found in economic accumulations. Igneous and metamorphic rocks are rarely porous and permeable… And rarely contain crude oil. Even if oil was commonly formed inorganically… It wouldn’t alter how and where oil companies look for oil. It still has to be trapped in porous and permeable reservoirs – Sandstones, limestones, shales and other sedimentary rocks. Even the oil that’s trapped in fractured granites and other basement rocks, had to migrate through and be trapped by sedimentary rocks.

          The process of hydrocarbon formation on Earth is very organized, has been observed at all stages in nature, can be quantified in a rigorous scientific theory and can be largely simulated under laboratory conditions. The only part of the process that cannot be directly repeated in the laboratory is time.

          https://wattsupwiththat.com/2019/04/23/abiotic-oil-realishthings-that-dont-matter-part-deux/
          https://wattsupwiththat.com/2017/02/18/oil-where-did-it-come-from/

          • Dave Middleton,

            I’d be grateful if you could give a pointer to information about thermal vents emission of light hydrocarbons. In return I can get you an image of light oil pollution of the ocean surface near the Lost City Hydrothermal Vent on the Mid-Atlantic Ridge.

            Light oil pollution reduces cloud cover. Lower cloud cover increases surface warming. I suspect it might be worthwhile checking sea surface images for trends in vent oil pollution.

            JF

            JF

          • Courtland, Rachel. “Deep-Ocean Vents Are a Source of Oil and Gas.” Nature News, Nature Publishing Group, 31 Jan. 2008, http://www.nature.com/news/2008/080131/full/news.2008.542.html#B1.

            Didyk, Borys M., and Bernd R. T. Simoneit. “Hydrothermal Oil of Guaymas Basin and Implications for Petroleum Formation Mechanisms.” Nature, vol. 342, no. 6245, 1989, pp. 65–69., doi:10.1038/342065a0.

            Fulton-Bennett, Kim, and Meilina Dalit. “New Study Challenges Prevailing Theory about How Deep-Sea Vents Are Colonized.” MBARI, 5 Sept. 2017, http://www.mbari.org/new-study-challenges-prevailing-theory-about-how-deep-sea-vents-are-colonized/.

            Fulton-Bennett, Kim, and Jenny Paduan. “MBARI Researchers Discover Deepest Known High-Temperature Hydrothermal Vents in Pacific Ocean.” MBARI, 10 Sept. 2018, http://www.mbari.org/mbari-researchers-discover-dee

            Hines, Sandra. “Lost City Pumps Life-Essential Chemicals at Rates Unseen at Typical Black Smokers.” UW News, University of Washington, 31 Jan. 2008, http://www.washington.edu/news/2008/01/31/lost-city-pumps-life-essential-chemicals-at-rates-unseen-at-typical-black-smokers/.

            Kelley, D. S. “A Serpentinite-Hosted Ecosystem: The Lost City Hydrothermal Field.” Science, vol. 307, no. 5714, 2005, pp. 1428–1434., doi:10.1126/science.1102556.

            Proskurowski, G., et al. “Abiogenic Hydrocarbon Production at Lost City Hydrothermal Field.” Science, vol. 319, no. 5863, 2008, pp. 604–607., doi:10.1126/science.1151194.

        • PeterT,

          Geologists have determined that Rock Oil (Petra Oleum) is biological in origin because of a range of confirming factors.
          First is the requirement for source rocks, organic rich marine or lacustrine shales that have been pressure heated to convert the organic material into mobile hydrocarbon fluids.
          All rock oils contain biomarkers, complex organic molecules that fingerprint the oil and link the hydrocarbon fluid back to the unique biological profile of the source rock.
          Brick clays are also relevant to this story. In order to fire a brick, it must have a component of organic matter mixed with the clay. Often brick clays are formed from water swamped organic rich forest soils.

          Pitchblende is a unique organic material of inorganic origin. It is associated with naturally occurring radioactive minerals. It is formed by radioactive induced polymerisation of methane gas and therefore is the only example of a purely naturally produced inorganic hydrocarbon.

          • Thanks. Learn something new everyday.

            I’m looking at a reference that says the carbon in pitchblende is thought to be a result of radiolytic polymerization of primativ algal or bacterial remains.

          • Right up until day one of my first semester in college, I thought “petro” referred to oil. In my first geology class, the professor went through a list of geology subjects. When he mentioned petrology, I was certain it was the study of oil… But it’s the study of rocks… Which is what I thought geology was… Turns out geology is the study of the Earth. Very confusing first day of college… 😉

        • Primordial hydrocarbons and water have been stripped of hydrogen from billions of years of solar radiation. Sure, our magnetosphere does a great job, but it isn’t 100%.

  3. This has no relevance to how hydrocarbons formed on Earth …

    Hydrocarbons formed on Titan and other bodies and we presume the process was abiotic. So, somewhere in the solar system, there are abiotic processes that lead to the creation of hydrocarbons. link

    The problem becomes one of explaining why hydrocarbons formed elsewhere in the solar system without biology but somehow that didn’t happen on Earth.

    It seems obvious that peat led to lignite led to hard coal. link We can extrapolate and assume that oil and natural gas are the result of biological processes too. On the other hand is there any reason to think that all natural gas must be the result of biological processes?

    • “is there any reason to think that all natural gas must be the result of biological processes?”
      commieBob
      Not necessarily, however there are some interesting pathways to explore for the biological formation of methane in basalts using hydrogen gas as a feedstock derived from the chemical breakdown of water.

      Bacterial communities were detected in deep crystalline rock aquifers within the Columbia River Basalt Group (CRB). CRB ground waters contained up to 60 μM dissolved H2 and autotrophic microorganisms outnumbered heterotrophs. Stable carbon isotope measurements implied that autotrophic methanogenesis dominated this ecosystem and was coupled to the depletion of dissolved inorganic carbon. In laboratory experiments, H2, a potential energy source for bacteria, was produced by reactions between crushed basalt and anaerobic water. Microcosms containing only crushed basalt and ground water supported microbial growth. These results suggest that the CRB contains a lithoautotrophic microbial ecosystem that is independent of photosynthetic primary production.

      Stevens, T.O. and James P. McKinley, J.P. 1995 Lithoautotrophic Microbial Ecosystems in Deep Basalt Aquifers. Science 20 Oct 1995: Vol. 270, Issue 5235, pp. 450-455

      Life on Titan & Mars perhaps?

      • There’s a difference between methane and natural gas.

        Methane can form in many ways, ranging from directly biogenic to totally abiogenic.

        Natural gas is composed of methane (60-99%), heavier hydrocarbons and various other compounds. It generally forms from the thermogenic cracking of crude oil.

        • “Methane can form in many ways, ranging from directly biogenic to totally abiogenic.”

          Back in the late 1990s, I started a company in SoCal to turn “green waste” into “natural gas” (i.e. methane). In all of my thousands of thermochemical calculations, it became apparent to me that methane was the preferred end state of any combination of hydrogen and carbon in any of their source compounds. Every experiment we did confirmed that.

          My approach was to pyrolyze wood waste into charcoal (recovering various volatiles, especially acetic acid, for sale), then combine the finely divided charcoal with steam to produce methane and carbon dioxide. It worked pretty well.

          Of course, the only reason it would have been profitable was that California governments paid “green waste” disposers $20 a ton to get rid of the stuff. Putting that in our income stream made the prospect profitable. Otherwise, it was a deadass loser.

    • CB: There’s no particular reason to think that hydrocarbons didn’t form on the early Earth. So far as we know, there are no sedimentary deposits remaining dating from the first half billion years of the Earth’s life although there are a few isolated Zircon crystals from that timeframe. And the few sediments that remain from the next billion years or so tend to be substantially altered in ways that would probably be hard on hydrocarbons. Keep in mind that heat and pressure tend on average to convert complex hydrocarbons to simpler forms. Eventually to methane

      Also, once life forms appeared, however that happened, they very likely ate a lot of any existing hydrocarbons just as they tend to do with loose hydrocarbons on the modern Earth. We don’t know for sure how life appeared on Earth, but we’re pretty sure it happened 3.77 billion years ago and possibly earlier.

      So far as I know, the oldest known hydrocarbon deposits (3.2-2.6 Billion years old) appear to be biotic, but I don’t see any reason to think that both biotic and abiotic hydrocarbons weren’t around long before that.

      There are rather a lot of processes identified that could generate organics from simple precursors under conditions that MIGHT have existed on the early Earth. Miller-Urey is probably the best know. But many others have been proposed.

      If I recall correctly Rud Istvan has posted in comments several times that there are a few natural gas seeps that appear to be modern (?) abiotic gas. (But no known massive, commercially exploitable deposits?). I’ve never looked into the claims. But I don’t see any reason not to think they might not be credible.

    • Abiotic methane is common on Earth. Simple hydrocarbons can form from geologic processes, unrelated to life.

      Crude oil isn’t methane. It is a mixture of complex hydrocarbons.

    • No one familiar with petroleum geology assumes “that oil and natural gas are the result of biological processes”. The source material is of biological origin. The process is not biological.

    • The carbon isotope ratios in natural gas indicates a biological origin. Incidentally this is even true of at least some of the coal in diamonds, showing that subduction can carry surface materials down quite deeply.

    • Any hydrocarbons in the atmosphere would have been destroyed as soon as free oxygen started existing in the atmosphere.
      The idea that there are hug pools of hydrocarbons inside the planet is nonsense for two basic reasons.
      1) Lighter stuff floats to the surface. Methane is much lighter than rocks and metals.
      2) The intense heat of the early earth would have destroyed it.

      • MarkW: “Any hydrocarbons in the atmosphere would have been destroyed as soon as free oxygen started existing in the atmosphere.”

        That’s probably pretty much true. BUT, it seems likely that the oceans on the early Earth contained vast amounts of dissolved Iron. Iron oxides are insoluble. It looks like once Oxygen started to form, it probably almost immediately combined with Iron to form a variety of Iron compounds — Hematite (rust) of course. And Magnetite, and a bunch of more exotic stuff. So a lot of the really old sediments on Earth are so-called Banded Iron Formations. Typically those are rocks composed of alternate bands of red iron stained material and bands of something else. Most commercial Iron ores are BIFs.

        Anyway, it’s possible that not a lot of Oxygen made it out of the oceans where early photosynthetic organisms presumably lived into the atmosphere. At least not until the dissolved iron was depleted. Which, we’re pretty sure, took many hundreds of millions of years..

        BTW, There’s a lot more to BIFs than the short explanation above.

    • “why so few craters ?”
      zemlik
      Two possible related geological reasons:
      1. Because Titan has a thick atmosphere with an active meteorological process involving wind and liquid methane rain. On Earth impact craters are eroded by water and filled with solid sand (SiO2) sediments. We should expect to find that on Titan impact craters are eroded by liquid methane and filled with solid water ice (H2O) and dry ice (CO2) sediments.
      2. Because Titan has a solid water ice crust covering an ocean of liquid water. On Earth we have a solid rock crust covering a mantle of hot plastic rocks. These Earth rocks can melt to create liquid lavas that reach the surface and fill in the surface impacts. On Titan the crust is solid water ice and below is hot liquid water. If an impact breaks the crust on Titan then the crater will be filled in with liquid water “lava” before it cools and freezes solid.

  4. The Green Blob don’t like talk about Hydrocarbons other than linked to something called “fossil fuels” which we all know are the root of all evil!

    It makes the Green’s nervous, when something goes against their beliefs. They will protest and say this is not the Truth, such science must be stopped.

    But even Saint Attenborough in his Blue Planet sermon, stated that Hydrocarbons were forming in the “smokers” in the depths of the ocean. “How dare he” say such a thing.

  5. So, Titan, the one place in our solar system with an “earthlike’ atmosphere density and exposed liquids, is also way ‘down’ there in an entirely different temperature regime! To me, it seems like Mother Nature’s little joke on us, that we can’t physically go there without melting right into the landscape, like so many “hot” godzillas! Go into the ‘lake’ and the lake starts boiling all around you! What a day at the beach!

  6. Why isn’t it on fire? Presumably there are ignition sources, such as lightning and geological activity. Is there no oxygen?

        • Actually boiling point of oxygen is -183C at 1bar, there is 1.45bar pressure on Titan. Oxygen boils at this pressure at around -168C. Temperature on Titan is 179C. So it looks that Oxygen is liquid under normal circumstances on Titan. You can use normal canisters as for fuel 🙂

    • BC
      One of the fun (and potentially dangerous) experiments we were shown in chemistry class at school in the 1960s was the creation of a flame of air burning inside a Perspex box filled with methane gas. We think of the methane as being a dangerous flammable gas, but in truth it is the oxygen in the air we live in which is the reactive agent that creates the flame. So, on Earth we pipe methane into our homes to create flames in air. On Titan the process is would be reversed and the pipes would carry oxygen to the flame of burning gas in the air of methane and nitrogen.

    • Free oxygen is rare in the Universe. That it is common on Earth is due to life. It is produced as a byproduct of photosynthesis. A very small proportion of the hydrocarbons produced by photosynthesis get buried (e g as peat, coal, kerogen, oil, natural gas). This leaves the corresponding amount of oxygen in the atmosphere.

  7. Don’t know about the rest of you but my take away from this post was that we should start preparing our defenses against attack from methane / ethane based organisms with superior technology.

    • Why would they want to invade an extremely hot world with a corrosive atmosphere of 20% Oxygen and lakes of corrosive Hydrogen Dioxide? It’d be like us invading Venus where the longest our “superior technology” has lasted to date is 2 hours and seven minutes.

      • Even worse than Venus is for us. It would be like us invading a planet with an atmosphere consisting of a mixture of superheated steam and chlorine.

        • Hydrogen hydroxide. HOH aka H2O aka so corrosive, it will eat all your robots and turn them into drifting particles of oxydized metal.

          When the first satellite orbited Titan, there was a discovery of a large lake that had islands showing during one season, and then they were flooded in another season. So Titan, with Saturn’s help, has seasonal changes, just like the other planets. Might be some useful compounds on Titan, too.

    • HO2 is hydropyroxyl radical.

      Very reactive, and one of the metabolic attack dogs that cause the 1000 or so mutations per day per cell in your body. Several 9’s of which get repaired right away.

  8. One of these days humans are going to know all about these moons and planets. The progress we have made in my lifetime is just amazing.

    We’re trailblazing!

    • This book is super-cool…

      It’s a survey of volcanoes on Earth,the Moon, Mars, Venus and Io, written as if it’s describing a geological field trip.

  9. One thing cool about Titan is you could walk on the surface without a pressure suit. Of course you’d need an oxygen-mask & some VERY warm clothing…..

  10. The Atacama Large Millimeter/submillimeter Array ALMA microwave telescope :
    https://alma-telescope.jp/en/news/press/band10-201811
    Stellar nebulas, presumably like the one this system formed from , are full of hydrocarbons, a list at the link.
    Have a look at the Cats Paw spectrum.

    As planets form it sure seems like this stuff gets concentrated. Anyway before life got started it looks like the necessary stuff just happened to be available.

    Strangely enough the Large Megallanic Cloud example has much less methanol than a main galactic one.

    There is much more to this story…

  11. Did anyone notice this?

    “Williams worked with the JPL team to identify what geologic units on Titan could be determined using first the radar images and then to extrapolate those units to the non-radar-covered regions.”

    So some portion of this map is at best an educated guess…at worst, just made up. I didn’t spend any time looking deeper, so don’t know how good the non-radar-covered data might be. It just set off an alarm bell when my skeptical mind saw this sentence…

    • The entire map is an “educated guess.” That’s all that’s possible with the data they currently have.

      Here we identify and map the major geological units on Titan’s surface using radar and infrared data from the Cassini orbiter spacecraft. Correlations between datasets enabled us to produce a global map even where datasets were incomplete.

      https://www.nature.com/articles/s41550-019-0917-6

    • Look at the quantity of the stuff ALMA has found in stellar nebulas.

      The darned galaxy is full of hydrocarbons, never mind all that H2 they cannot optically see.

      OMG – we have to clear the Galaxy of CH4 , better call Greta quick!

  12. Plate tectonics is probably the most significant aspect of earth’s geology, not erosion. Is there any evidence of such processes on Titan? The map doesn’t seem to indicate any.

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