Planetary Stretch Marks: More Evidence For Expansion Tectonics

Topic: How does plate tectonics explain stretch marks on planets (e.g. Mercury) and moons (e.g. Callisto) that have no plate tectonics?

Below: Mercury's Stretch Marks

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Below: Valhalla Crater (Callisto)

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"The apparent widening in diameter and flattening of older craters, is what one would expect to observe, if the exterior crust were slowly stretching. This is a very common observation on all rocky planets. The formation of concentric rings as present on the surfaces of Callisto and Mercury can show the effects of a gradual expansion with time." (Harms 1998)

 

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"The apparent widening in diameter and flattening of older craters, is what one would expect to observe, if the exterior crust were slowly stretching. This is a very common observation on all rocky planets. The formation of concentric rings as present on the surfaces of Callisto and Mercury can show the effects of a gradual expansion with time." (Harms 1998)

 

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What's the publication this quote is mined from?

 

That's irrelevant to whether it's true or not. Something need not be published in order for it to be true.

But since you can't debate without ad hominem and personal attacks here you go: http://www.johnkharms.com/

Insult him however you like.

 

How are we to know who the author is and what the original context is? Why are you afraid to reveal the publication?

 

You mean how are you supposed to know who to attack with insult and ad hominems? You could try google or something but that would require reading, effort, and research. Source posted above.

 

To the casual reader, this is the typical response from a pseudoscience proponent that makes a claim and is challenged: "do your own research."

Rather than support claims with genuine peer-reviewed work, they offer quotes mined out of context from real scientific works or present quotes from non-scientific sources dressed up as science. This, casual reader, is pseudoscience.

I'm betting OIM has cited a source that is a fellow crackpot and not an actual researcher and is, thus, hesitant to show this link since he's already dressed the quote up to appear as a scientific one when it's really just a crackpot.

And, yes, ad hominem is the correct term for the argument when I say crackpot. But this is also a label that is useful and accurate given the anonymous sources probable beliefs and pseudoscientific outlook.

 

This is a topic/thread best suited for the Pseudoscience subforum. Please move.

 

LOL @ U.

I think all plate tectonics threads belong in pseudoscience.

 

Lucky for the rest of the world, science doesn't revolve around your crackpot beliefs.

 

This is a strawman argument, since there is no citation to a claim that anyone here (or elsewhere) is claiming that "plate tectonics" created "stretch marks" on either of the two solar bodies mentioned.

The anonymous author above is clearly not educated in planetary sciences or even basic geology. If she went to school, she certainly shouldn't have left so early.

There is no "apparent widening in diameter and flattening of older craters" and there is no indication from this mysterious, undereducated author (assuming that OIM has maintained the context of the quote) that this is "what one would expect to observe, if the exterior crust were slowly stretching." By indication, I mean there's no demonstration of why such a concentric ring system would be present -no mathematical formula, empirical data, etc.

What *is* shown in the photo of Callista's Valhalla crater, however, is an impact and the resulting concentric rings that are a function of the thickness and strength of Callisto's lithosphere as well as the crater's diameter (McKinnon & Melosh 1980; Melosh 1982). These are the results of impact, which is a far, far more parsimonious explanation than "planetary expansion," which has no supporting data which can be tested. Impacts, however, can and have been tested on many occasions (Melosh 1999).

The dozens of grabens that surround the Valhalla impact crater are a result of the low-viscosity or low-strength of Callisto's lithosphere. A thin, weak lithosphere is the explanation for concentric rings (Luttrell, 2006; McKinnon & Melosh 1980; Melosh & McKinnon 1978). Not the pseudoscientific 'expansion' claim.


References:

Luttrell, Karen & David Sandwell (2006). Strength of the lithosphere of the Galilean satellites Icarus, 183 (1), 159-167.

McKinnon, William B. & H. J. Melosh (1980) Evolution of planetary lithospheres: Evidence from multiringed structures on Ganymede and Callisto, Icarus, 44 (2), 454-471.

Melosh, H.J. & B.A. Ivanov (1999). Impact Crater Collapse. Annual Review of Earth Planetary Science, 27, 385–415

Melosh, H.J. & W. McKinnon (1978). The mechanics of ringed basin formation. Geophysical Research Letters 5, 985–88

Melosh, H.J. (1982). A simple mechanical model of Valhalla Basin, Callisto. Journal of Geophysical Research 87, 1880–90

 

Because I read and learn new things as time passes.

Here is another argument I didn't rely on.

"Over twelve years of laser ranging to the LAGEOS spacecraft have enabled the motions of the Earth's crust to be determined at approximately twenty laser tracking sites around the world. ...The relative motion of Hawaii and Arequipa is 80±3 mm/yr from our solution compared to the geologically predicted 66 mm/yr." (Smith et al, 1990).

So if Hawaii and Arequipa are moving away from eachother at 80±3 mm/yr, then the Nazca Plate cannot possibly be subducting. Therefore the Pacific is growing.

Furthermore, +65.33 mm/yr increasing width between Yaragadee Australia and Arequipa Peru (Smith et al., 1993). Therefore the Pacific is growing.

 

What publications are these quotes from?

 

A question is not an argument...

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The author isn't anonymous. Furthermore ad hominem fallacies are not a logical or scientific argument...

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The 1990 paper is titled "The determination of present-day tectonic motions from laser ranging to LAGEOS." It was published in Developments in Four-Dimensional Geodesy. The 1993 paper is titled, "SLR Results from LAGEOS." However the exact paper is irrelevant since the scientific literature contains countless papers purporting to prove subduction, but which unwittingly include several measurements that show the Pacific Ocean basin to be increasing in width--not decreasing in width as required by subduction.

 

Ad hominem arguments are a part of logic as well as being fallacious. They can, and do, have their places in debate, particularly with skillful and timely placement. This, you would also have learned in a first year philosophy course. As far as being scientific, none of what you're presenting is "scientific." This has been demonstrated time and again.

This is another of your complete and utter faults. Not only have you completely removed a quote from its original context, you consistently do this and hide the original texts so that others cannot review and see the contexts for themselves.

The quote above (Smith, D.E. et al 1990) isn't a paper at all but a part of a book chapter.

Had you bothered to retrieve the entire chapter, you would have read a work that demonstrates and supports the plate tectonic model with empirical data. As a sample, here's a quote:

This is the sort of prediction that the plate tectonic model predicted and was demonstrated as early as 1990.

Since that time, many such measurements have been made which, likewise, support the plate tectonic model and not a single bit of testable, empirical data has ever shown the pseudoscientific claim of "earth expansion" to be the supported.

Here's a question: what is the rate at which you suggest the Earth is expanding over what period of time?

Reference:

Smith, D.E. et al (1990). "The determination of present-day tectonic motions from laser ranging to LAGEOS," Developments in Four-Dimensional Geodesy. Berlin: Springer Publishing.

 

Unfortunately personal insults and ad hominem attacks are explicity against forum rules.

 

Okay. I apologize.

Now, you're free to address the other content of my posts or concede that you know nothing of the science behind geologic processes. Your arguments are pseudoscientific and that is not an ad hominem remark.