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Posted by: Webscientist Feb 13 2008, 08:49 PM

The latest news about Titan reveal that, according to a study led by Ralph Lorenz, the orange moon has hundreds of times more liquid hydrocarbons than all the known oil and natural gas reserves on Earth.
This estimate is close to the estimate made by independant authors, presented at the following webpage: http://www.planetaryphysics.com/Researchworktitanlakes281007.htm
The authors conclude that the liquid hydrocarbon reserves in Titan's arctic lakes might well be at least 650 times greater than the proven oil reserves on Earth. The key factor for obtaining the estimate appears to be the mean depth, postulated to be 250 meters, here.
Unfortunately, it won't change anything on oil prices! ( unless speculators...)

Posted by: nprev Feb 13 2008, 09:05 PM

Unfortunately, gas would have to hit a few tens of thousands of US$s per gallon to make any sort of resource exploitation even remotely feasible. Thinkin' I'll be walking to work a long time before THAT happens...

Posted by: Juramike Feb 13 2008, 09:21 PM

Awesome!

We can "crack" water to make oxygen, burn the hydrocarbons in internal combustion engines and produce CO2 to our hearts content without worrying about global warming. In fact, we'd probably have to worry about causing global cooling since CO2 has a lower GWP than methane. (GWP: http://en.wikipedia.org/wiki/Global_warming_potential)

Titan land of Big Weather and Bigger SUV's.

-Mike

Posted by: nprev Feb 13 2008, 11:09 PM

Yep...you just coined the first slogan for the Titanian Chamber of Commerce tourism campaign there, Mike! I wanna jump me some dunes in my 700HP 4x4...gotta have a sleeveless spacesuit though, do have a certain image to preserve...

Posted by: volcanopele Feb 13 2008, 11:16 PM

Blar! I was hoping no one would realize how much petrol you could get up in the north... There goes cornering the market in Titanian Natural gas. Besides, on Titan, I can have a nice SUV and I don't have to hear some whiny environmentalist complain about it.

Love the slogan!

Posted by: JRehling Feb 13 2008, 11:28 PM

The bright side is that even if you did increase Titan's temperature, it would only make it more comfortable. The down side is that Titan would start losing volatiles and you'd eventually find yourself on another Ganymede.

Posted by: nprev Feb 14 2008, 03:17 AM

Hmm. You raise an interesting question, JR, though probably not one easily answered: How much would the mean surface temperature of Titan have to be raised to begin losing its atmosphere?

I seem to recall some speculation that once the Sun enters its red giant phase Titan might become literally Earth-like, at least in accordance with primordial Earth models. Sounds pretty far-fetched to me (much more so after Cassini's revelations, in fact). Unfortunately, I think Titan will go <poof> in just a few million years after this happens & as JR said become another Ganymede, provided that the present atmosphere can even last until then (got my doubts there, too).

Any number-crunchers have some data to share? I don't want to commit to renting an SUV on Titan till I know how long the place is gonna be wild & foggy; ain't no fun jumpin' dunes in a vacuum, the dust ain't got no hang-time!!! <snort><spit><scratch>...<grunt> (Gee, can ya tell I'm from Montana?...)

EDIT: Fairly silly OT observation here, but what the hell are future residents of Uranus' moon Titania going to use as the possessive form of its name? All I can think of is "Titaniaian", which, when pronounced, actually sprained my epiglottis. We may have to avoid colonizing this place out of fear of strangling its residents.

Posted by: volcanopele Feb 14 2008, 03:48 AM

I figure it will be resolved the same way Georgians from the Caucasus and Georgians from the Southern US aren't confused very often: context, dialect/language. IF you are talking about working with the Titanians at one of their new oil refineries, you probably aren't talking about moving to Titania.

Posted by: Rob Pinnegar Feb 14 2008, 05:16 AM

Besides that, place names can change over time. If people ever start living on Titania, they might decide to change its name to something they like better.

Posted by: rlorenz Feb 14 2008, 03:42 PM

Doesnt get the headlines so much as the lakes, but our paper also evaluates the volume of the dune
deposits (=100s-1000s times the coal inventory on Earth..) as well as some of the sediment-generating
processes

Posted by: tty Feb 14 2008, 08:46 PM

Spreading hothouse gases on Titan is certainly an intriguing idea. However we had better find out more about the surface chemistry first. As suggested in another thread some of those complex organics may be quite unstable if heated. Having the whole surface suddenly go bang might be a bit awkward.

Posted by: volcanopele Feb 14 2008, 08:53 PM

Personally, I think colonists would use what ever is cheap and easy to obtain when it comes to energy sources. For Io, you would obviously go with geothermal (or iothermal). On Titan, hydrocarbons make sense.

How much would obtaining energy from hydrocarbons on Titan heat the place up? CO2 would largely freeze out (or if you are that worried about, just do what some have been advocating here, sequester it), for example.

Posted by: Juramike Feb 14 2008, 09:43 PM

Exactly.

CH4 is a much more efficient greenhouse gas than CO2. I doubt that the slight amount of CO2 kicked into the atmosphere will do much compared to the natural variation of methane. (H2O is also a greenhouse gas as well)

Course, the CO2 (and H2O) would like to stay as a frozen solid on the surface. It's real easy to sequester the stuff when you can shovel it around (and guessing wildy about the vapor pressure of CO2 at that temperature, it's probably not necessary to sequester it).


But you've got much better options for generating "clean" and easy power on Titan:
Wind (in the equatorial zones), low speed but the higher pressure should give more "oomph" per m/s.
And the hydrocarbon equivalent of a hydroelectric plant in the temperate, polar zones. (gotta find some streams that move).

[I think all these and more were discussed in a previous thread somewhere in here.]

-Mike

Posted by: helvick Feb 14 2008, 09:50 PM

How (exactly) are our colonists going to liberate much energy from these hydrocarbons ? What do we propose as an oxidiser for these hydrocarbon burning mega-SUV engines?

Posted by: Juramike Feb 14 2008, 10:31 PM

Oxygen from electrolysis of water.

Wind power generates electricity, water electrolyzed to hydrogen and oxygen. Oxygen would be "bottled" and would be the Titan equivalent of a tank of gasoline. The oxidizer part of the equation would be the more energy-intensive stuff to generate and store safely.

In comparison, the hydrocarbon part would be easier to get, just scoop up and refine and pour into a second fuel tank. (Combustion motors on Titan would require two tanks - one for the oxidizer, one for the fuel).

On Titan, the hydrocarbon tanks would be relatively safe from accidental spillage. (A little extra hydrocarbon spilled outside in a reducing atmosphere is not a major safety hazard.) In comparison, the oxidizer would be dangerous, organic fuel would be omnipresent in the environment.

-Mike

Posted by: helvick Feb 14 2008, 11:39 PM

Hmmh - it's doable but some back of the envelope numbers make me think that it takes about 5kWhr to electrolyze 1 litre of water which yields about 890grammes of O2. You need approximately 4x the mass of O2 to burn hydrocarbons so you will chew up slightly more than 22kWh for each kg of hydrocarbon fuel you eventually get to burn. A kg of petrol\gasoline liberates about 12kWh of convertable energy when burned in an efficient internal combustion engine so you would need to use about 20kWhr to generate the oxygen that you will subsequently use to generate 12kWhr of work.

That seems like a very inefficient energy exchange - surely you would be way better off using batteries\fuel cells?

Posted by: centsworth_II Feb 15 2008, 12:17 AM

Why would you not just use the hydrogen liberated at the
same time as fuel rather than processed hydrocarbons.

Posted by: Juramike Feb 15 2008, 12:57 AM

Ummmmm......because H-powered SUV's haven't come out yet?

(Emoticon meant for automobile manufacturers only: )

-Mike

Posted by: tty Feb 15 2008, 01:17 PM

I'm not sure that would be the best way to run it on Titan. Here on Earth we have limited fuel and unlimited oxidant, so we go for oxygen-rich ("lean-burn") full combustion to use the fuel optimally. On Titan we would have limited oxidant and unlimited fuel so it might be better to use "fat-burn" partial combustion and use the liberated energy to heat/decompose the unburnt fuel fraction. It would make for a very dirty exhaust, but that is hardly a problem on Titan.

Posted by: EckJerome Feb 15 2008, 07:12 PM

If you'll forgive an old lurker interjecting a potentially volatile question...

Given the incredible abundance of hydrocarbons on Titan and elsewhere in the solar system, why do people so tenaciously cling to the theory that hydrocarbons on Earth can only be of fossil origin? My layman's understanding is that fossil origin theory derives from a single piece of evidence, that being the presence of an isotope which can only be the result of biological activity. However, with the discovery deep rock bacteria, it is entirely possible that hydrocarbons on Earth are being affected by active underground life rather than having been created by life. Few people seem to be aware of the sketchy nature of the evidence pointing to fossil origin when, in fact, there is a great deal of evidence against it.

http://www.oralchelation.com/faq/wsj4.htm

Now, don't get me wrong...I'm not a pave-the-Earth type and I fully support the wise-use and conservation of resources, but I firmly believe that politics has decided the scientific consensus on this issue.

Thoughts?

Posted by: dburt Feb 15 2008, 10:10 PM

Hardly my specialty, so I won't give you a lot of links, just a couple of comments. First, comparing Earth and Titan, there clearly is more than one way to form hydrocarbons. That said, there is extremely abundant geological and geochemical evidence that the vast majority of hydrocarbons (including petroleum, natural gas, and coal) on Earth were formed by life - that is why they are called fossil fuels. If small quantities are being produced by other (inorganic) means, they clearly are insufficient to come anywhere close to replacing those that our civilization currently is using (and arguably wasting) for energy, chemicals, and plastics. The observations described in your old link can probably be explained by other means, including the fact that petroleum is a liquid that is less dense than liquid water. It therefore normally migrates upwards from where it is formed to where it is trapped beneath an impermeable layer, such as a salt or clay bed. If geologically young, it could therefore appear to be replenishing itself.

The organic vs. inorganic formation of the simplest hydrocarbon, methane or CH4, is of special interest for Mars, where tiny quanitities have tentatively been detected in the atmosphere. Whether this finding might indicate microbial life is an open question.

Some of the Houston petroleum types who post here should probably add to these comments.

-- HDP Don

Posted by: EckJerome Feb 16 2008, 12:00 AM

Perhaps I was a bit ignorant in my statement of the "sketchy" nature of biogenic origins of hydrocarbons on Earth. Having done a bit of web-surfing on the subject, I see that most western geologists believe that while there may be small amounts of abiogenic hydrocarbons, the vast majority of deposits are biogenic in origin. Thomas Gold, an astronomer, was one of the few proponents of abiogenic origins of petroleum in more recent times. Of course, nobody explores for petroleum based on abiogenic theories so it would seem the theory has not been tested much either.

Admittedly, my opinions came from my father who was a petroleum geologist in Canada and a bit of a maverick regarding many currently accepted theories. That said, he had a very successful record of locating oil deposits, remaining in demand as an independant consultant even as North American exploration came nearly to a halt. Later in his career, he specialized in the study of abandoned oil fields...pinpointing the locations of additional deposits either missed in the original drilling, or made accessible by new technology. I have no idea if he used his own maverick ideas in determining where to drill. (Nor can I call him in grave to quiz him.)

Posted by: dburt Feb 16 2008, 01:53 AM

Vast experience and an unusual aptitude for visualizing buried structures in 3-D were probably the keys to your father's success. That is, I doubt if he ever found much oil in igneous or metamorphic rocks, which the abiogenic hypothesis suggests could contain as much hydrocarbons as fossiliferous sediments. Although such rocks are rarely, if ever, drilled for petroleum, they commonly are drilled for many other purposes (e.g., exploring for groundwater or mineral deposits) and petroleum and other hydrocarbons generally are not encountered. An extremely deep drill hole in Sweden, drilled in part to test Thomas Gold's abiogenic petroleum hypothesis, was unsuccessful. At roughly $100 per barrel of oil currently, any hypothesis, no matter how wild, will be tested. The biogenic idea of organic-rich source sediments that are buried and heated in the so-called "petroleum window", upwards migration of petroleum liquids through denser aqueous brines, and trapping beneath an impermeable barrier (the best barriers are evaporites), is the only one that has proven consistently successful on Earth. Furthermore, modern "biofuel" production deliberately uses biological processes to generate hydrocarbon liquids (although current methods have many hidden costs). Again, biology may not be the only way to make petroleum or other hydrocarbons, but it seems to predominate on Earth.

-- HDP Don

Posted by: centsworth_II Feb 16 2008, 07:48 AM

Either way, I don't think it changes the fact that natural hydrocarbons on Earth are a
non-renewable resource when looked at on a scale of hundreds of years.