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Author Topic:   Young earth explanations for Angular Unconformities
iceage 
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Posts: 1024
From: Pacific Northwest
Joined: 09-08-2003


Message 1 of 202 (349887)
09-17-2006 11:53 PM


The best evidence for a very old earth are angular unconformities. Angular unconformities require several distinct steps each requiring significant lengths of time.

1. Deposition
2. Lithification (http://en.wikipedia.org/wiki/Lithification)
3. Sometimes metamorphosis
4. Tilting
5. Erosion
6. Deposition
7. Lithification
8. Tilting again on occasions.

http://en.wikipedia.org/wiki/Angular_unconformity
http://perlworks.com/geology/angular_unconformity/triassic_sandstone.jpg
http://perlworks.com/geology/angular_unconformity/syncline_unconformity.jpg

The nice thing about unconformities is that they are common and visible in road cuts everywhere. They do not require any assumptions about decay rates, the speed of light, absorption rates, etc.

What are the young earth explanations for angular unconformities?


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iceage 
Suspended Member (Idle past 5187 days)
Posts: 1024
From: Pacific Northwest
Joined: 09-08-2003


Message 15 of 202 (350522)
09-19-2006 10:53 PM
Reply to: Message 1 by iceage
09-17-2006 11:53 PM


Siccar point and YEC
I am somewhat disappointed that there is no resident Young Earth geologist here to provide a different "interpretive framework". So I had to do my own digging.

I have found two articles that revisit the most famous unconformity of Siccar Point - from a young earth perspective.

http://www.biblicalcreation.org.uk/scientific_issues/bcs100.html
http://biblicalgeology.net/content/view/55/9/

Both seem to indicate that since the contact point is flat (at least in one image provided) and does not show "differential weathering" that the lower rock strata were eroded in a high-energy environment - i.e. global flood.

One thing I noted is that both articles used the same image.

At this site

http://www.geos.ed.ac.uk/undergraduate/field/siccarpoint/images.html

I found images like this

http://www.geos.ed.ac.uk/undergraduate/field/siccarpoint/dscn0320.jpg

Which shows a much more differential erosion contact zone. Notice in the upper right the sandstone extending down the outside of one of the fingers. The flatness of the contact I would guess would depend dramatically on if you were looking at the contact parallel or perpendicular to the flat vertical layers. I would surely be disappointed if the above YEC articles cherry picked their images.

Also both articles provide no rational short-term flood model on how this formation formed other than noting that the features indicate high-energy processes. The second article even noted that lower material was metamorphosed. However, no acknowledgement that such a process would require long periods of time but a note that metamorphoses requires water, imply that this material was saturated, by the great flood I suppose.

Also the author of the second article mentions that the lower layers are folded.

quote:
Not only were the lower rocks deposited quickly, but they were folded while they were still soft and contained abundant water. The beds do not indicate evidence of brittle fracture. So they must have been folded while still plastic

The author is a mechanical engineer but ignores the well-known process of solid-state creep and the plastic deformation of brittle materials at high pressures and temperatures. Creep requires and indicates long periods of time.

Also mention in the article is the presence of breccia or fragments of the base material in the overlying sandstone. This breccia extends for several feet into the younger sandstone.

http://www.geos.ed.ac.uk/undergraduate/field/siccarpoint/dscn0324.jpg

Would it not be reasonable to expect that this breccia is the result of the upper ends of the differential eroded parts breaking off after the upper layer deposition began? In other words the “fingers” sticking through the newly layering deposited sand would break off from weathering and the fragments would lay deposited in a mixture of sand resulting in a flatter contact appearance.

From my view angular unconformities such as Siccar point disprove a young earth as powerfully as a picture of planet earth from orbit disproves a flat earth.


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iceage 
Suspended Member (Idle past 5187 days)
Posts: 1024
From: Pacific Northwest
Joined: 09-08-2003


Message 20 of 202 (418240)
08-27-2007 2:14 AM
Reply to: Message 19 by Ihategod
08-27-2007 12:49 AM


Re: compelled to reply
Vashgun writes:

I would like to point out that no one really answered the question, instead jumped on the bash-creationism-bandwagon.

Well that is because no young earth creationist cared or dared to respond. And not without reason!

The reason that Angular Unconformities are a powerful evidence of old earth is that their interpretation does not require relying on others for the observation - they can be observed first hand. This is not the case with tree ring counting, radiometric dating techniques, star and galaxy distances, magnetic reversals, etc.

First question: How do you know that erosion shaped the rocks?

I suppose you are referring to why does the underlying layer appear to be cut at an angle to the sediment layer. I cannot not even suggest an alternative explanation in either view point - young or old earth. That is what could possible lay down sediment layers like....

////////////

Vashgun writes:

Second question: Could it have been a relatively short intermediate period between lower formation and upper layer?

Now that is a possibility.

However, we do know that often the lower layer of Angular Unconformity are considerably more metamorphised than the upper layer. Metamorphic rock is rock that has experienced high heat, high pressure and time as the result of being deeply buried. This implies that the lower layer and upper layer lithified under very different conditions and over different lengths of time.

Note that if one were to find an unconformity where the upper layer is more metamorphised then the bottom layer this would present a very serious problem (falsification).

The Great Unconformity at the bottom of the geological column of the Grand Canyon and Siccar Point are examples where the bottom layer are much more metamophised then the upper layer.

For reference here is a drawing of the Unconformity of the Grand Canyon....

And here is an actually image of the Grand Canyon Unconformity...

Vashgun writes:

Third question: I viewed as many pictures as I could find yet, the only real speculative angular unconformity I saw was a drawing on wikipedia. Why isn't there better evidence?

Angular unconformities are *not* speculative!!!! I visited your link to the wiki and found three images of real angular unconformities.

Angular Unconformities are are quite common. The one at the bottom of the Grand Canyon is very visible - you can put your hand across the contact.

Siccar point is another famous angular unconformity. Visit the linked reference below for hi-res images.

http://www.geos.ed.ac.uk/undergraduate/field/siccarpoint/images.html

here are many more here...

http://images.google.com/images?q=angular+unconformity

Here is another in Yellowstone National Park (taken by yours truly).


This message is a reply to:
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iceage 
Suspended Member (Idle past 5187 days)
Posts: 1024
From: Pacific Northwest
Joined: 09-08-2003


Message 35 of 202 (418407)
08-28-2007 12:04 AM
Reply to: Message 26 by Ihategod
08-27-2007 11:10 PM


Learn more
Vash writes:

Instead of jumping all over me and telling me how classic it is for a creationist to be so stupid, perhaps you should stop stroking your over-inflated egos and help me understand this topic

Vash we are all born with inflated egos - comes with being human.

If you are really interested take up a study course of your own and be skeptical of everyone and every source. After a while you began to detect when someone is trying to deceive via logical fallacies, filtering data and appealing to emotion arguement. You also pick up on just plain ignorance. Try not become invested in any particular mindset always willing to change and adjust to new data and ideas.

When I started looking into the old vs young earth I was probably biased towards young earth because of my background. The data just started stacking up that it soon became undeniable - angular unconformities, extremely complex surface geology where each formation represented long time periods, formations on top of formations on top of formations, large eroded basins, colossal deposits of sand and microfossils, incised river meanders, fossilized agatized wood, extensive ice age and glacier remnants, etc.

These evidences coupled with the realization that the scale of the universe is way beyond our normal everyday human comprehension it seems to fit that the universe and earth are also extremely old beyond our comprehension (not to mention the physical fact of the time required for light to travel the distances involved). Deep space corresponds with deep time.

Now look I am off topic on my own thread.


This message is a reply to:
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iceage 
Suspended Member (Idle past 5187 days)
Posts: 1024
From: Pacific Northwest
Joined: 09-08-2003


Message 42 of 202 (418746)
08-30-2007 2:12 AM
Reply to: Message 38 by Ihategod
08-29-2007 11:30 PM


Angular Unformities are Not Circumstantial
Vashgun writes:

First, I would like to point out that the position on angular unconformities comes from a priori knowledge and application of Steno's Principles. If I may say so this theory is super sketchy.

The principle that lower layers are older than upper layers is super sketchy !?

Other than the fact that it is relatively intuitive and common sense this "theory" has been proven to beyond a show of a doubt via radiometric dating, magnetic reversal markings and known events such as volcanic ash layers. Heck my desk serves as a great model - if I want to retrieve a document from say June I know I have to reach down about 1/4 of the way down.

Vashgun writes:

What is the foundations of this principle ?

Time, observation, simple reasoning.

Vashgun writes:

I don't understand why it couldn't have happened with enormous amounts of fluctuating liquid.

Fluctuating liquid in what way?

Vashgun writes:

The more water over a certain area the more "lighter" particles will drift up.

What? Why would more water over a certain area influence "lighter" particles to drift up? Water depth does not influence the density of a particle. Some non-standard physics at work here.

Vashgun writes:

With massive waves of varying oscilating degrees I don't see how this couldn't account for unconformities and different groups of layers on top of each other.

This is so vague that it is impossible to comment.

Vashgun writes:

Thirdly, it seems as if while reading the rebuttals to the flood, which are extraordinary in volume, there is an assumption of conformity to the prescribed yec theories. As if by proposing a new theory it must therefore must have no unconformities or paradoxes. It isn't to say this shouldn't be held up to inquisition, rather not treated as a law of the universe whilst the theory is in infancy.

No Comprende! Sorry but I can't figure out what you are trying to convey.

Vashgun writes:

Fourthly, there would have been an enormous amount of environmental change when the flood happened. As supposing a catalyst, such as a huge ice-meteorite to cause the north american ice age and tilt of earth's axis, it's possible that what could have transpired would be at best marginal in assumption to determining the process by which our world now rests.

Wow so much wrong in such a short paragraph....

There are no signs of impact of an ice-meteorite, ice floats which would present a significant problem for a simultaneous ice age, ice-meteorite, flood theory (creative but not supported by *any* evidence), the ice age was certainly NOT constrained to North America! or the even the northern hemisphere and *several* ice ages have occurred in the past.

Vashgun writes:

Furthermore, I have yet to witness a damning argument against the flood.

There are many. Spend some time looking and you will find an overwhelming amount of evidence.

Vashgun writes:

I read this was the best evidence, yet I see surface unconformities that if I looked upon them while trekking the wilds would assume it was relatively recent erosion.

What is a "surface unconformities". Angular Unconformities occur through out the geological column. Links were provided. You just can't get a nice picture of buried unconformities.

The Great Unconformity at the bottom of the Grand Canyon is 10,000 ft from the rim of the canyon - it is only on the "surface" because a river carved a deep canyon.

And your comment "relatively recent erosion" demonstrates that you are missing the arguement. Angular unconformities involve *two* separate deposition and lithification events with an erosional episode in between (not to mention a tilting event). As stated often the lower layer is metamorphosed. This implies deep burying, which further implies uplift to bring this formation back to the surface for erosion to act.

Further Angular Unconformities are not the "best evidence" against the flood. Angular Unconformities are just one of several evidences (others include river meanders, chalk deposits, lava layers) that are readily available and do not require reliance upon other peoples observations like do radiometric dating, dendrochronology, varves with seasonal markings, batholith cooling rates, magnetic reversals, deeply buried sediment basins, buried river canyons, etc. on and on.

Vashgun writes:

I am not doubting the existince of any unconformities in the rock strata, it is that the evidence has been purely circumstantial.

Just what exactly is circumstantial? The evidence is readily available and observable - the implications are clear - the explanations are simple. Are you being honest with yourself?

There are absolutely no rational flood explanations at all.

Edited by iceage, : No reason given.

Edited by iceage, : Added sub-title


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iceage 
Suspended Member (Idle past 5187 days)
Posts: 1024
From: Pacific Northwest
Joined: 09-08-2003


Message 86 of 202 (424120)
09-25-2007 5:20 PM
Reply to: Message 83 by CTD
09-25-2007 3:31 PM


Long Time Periods Required
CTD writes:

Earlier in the thread, the whole line was "creationists are scared to death of unconformities because they disprove the flood." Now it's more like "We think we have enough unconformities available that we hope we can find one a creationist can't explain."

I am sorry that you have the sense that some feel that a YEC model can explain *any* known Angular Unconformity.

If one considers the time required for lithification (ie dewatering, compaction, cementation) you could not find a single unconformity that would fit within the Young Earth model. Consider that you have two separate geological formations that are lithified at separate times. Each Lithification event by itself excludes a young earth consideration. This is ignoring the time periods required for erosion, deposition, uplift, etc.

CTD writes:

I seem to recall reading that these things actually make a good case for the flood, but I don't have access to my books now.

A flood cannot account for an unconformity. Every YEC explanation I have come across involves hand waving, an impossible sequence of events and a complete detachment from known physics even when considering the scale of a global world wide flood. This is the reason you will find very little discussion in YEC literature. It is a very large elephant in the YEC living room.


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iceage 
Suspended Member (Idle past 5187 days)
Posts: 1024
From: Pacific Northwest
Joined: 09-08-2003


(1)
Message 87 of 202 (424181)
09-26-2007 2:23 AM
Reply to: Message 72 by Minnemooseus
09-19-2007 2:33 AM


Re: Iceage, from the "Grand Canyon Paradox" topic
Minnemooseus writes:

(I)f it were to be high grade metamorphosed it would no longer be a bedded sediment. By definition, an unconformity with the lower rocks being high grade metamorphics or intrusives would be a nonconformity.

However a high grade metamorphic formation may have vestigial components that reveal the original sedimentary features and bedding plane.

Minnemooseus writes:

There are two unconformities at the bottom of the Grand Canyon. The lowest one indeed is over high grade metamorphics, and is a nonconformity. The higher (the Great Unconformity) is an angular unconformity.

i have never had the joy of hiking down to the bottom of the Grand Canyon but have explored the north rim area.

A number of authors refer to the bottom unconformity as an Angular Unconformity and some the "Greatest Angular Unconformity". I can only assume this is due to markers or vestigial bedding planes. I found this wonderful paper from 1933 demonstrating some remaining sedimentary structures in the Vishnu.

http://www.pnas.org/cgi/reprint/19/9/806.pdf

Further this link even provides some details of the Vishnu Group and even gives the general sedimentary beds angle and refers to the contact as an Angular Unconformity.

http://www.thebestlinks.com/Geology_of_the_Grand_Canyon_area.html

Reference link writes:

Vishnu Group

About 2000 million years ago in Precambrian time, thousands of feet of ash, mud, sand, and silt were laid down in a shallow forarc basin behind an orogenic belt of mountains and volcanoes in an island arc. No fossils have been found in these strata.

1700 to 1600 million years ago the process of plate tectonics compressed and heated these marine sediments into the metamorphic rock now exposed at the bottom of the canyon in the Inner Gorge. Geologists call this dark-colored, garnet-studded layer the Vishnu Schist. This combined with the other schists of this period, the Brahma and the Rama, make up the Vishnu Group (see 1a in Figure 1). This layer was later intruded by blobs of magma rising from a subduction zone offshore. These plutons slowly cooled to form the Zoroaster Granite (seen as light-colored bands in the darker Vishnu Schist; see 1b in Figure 1). Some of this rock eventually was metamorphosed into gneiss.

100 million years later in Paleozoic time, an orogeny (mountain-building event) uplifted the region and created the 5-6 mile (8-9.5 km) high Mazatzal Mountains and tilted the beds 15°. For 200 million years erosion stripped much of the exposed sediments and the mountains away and thus left an angular unconformity in the area's geologic sequence. The roots were all that remained of the Mazatzal Mountains as the sea reinvaded the area. Today the Vishnu Schist and the Zoroaster Granite are exposed in the Inner Gorge of the canyon.

And another reference Pillar Of Gold by George H. Billingsley of the U.S. Geological Survey refer to the contact between the lower Vishnu and the upper GC Supergroup as the "Greatest Angular Unconformity" (see lower left corner)


Click to enlarge

One more reference Geology of National Parks By Ann G. Harris, Esther Tuttle, Sherwood D. Tuttle also refer to this contact as Angular Unconformity.

However definitions aside the Vishnu group had to be buried considerably deeper than it is today in order for it to be metamophosed as it is. Also I believe that the Vishnu Group extends several miles below the current exposed layers.

These various steps of deposition, deep burial, metamorphic conversion, fracturing, intrusion, uplifting and tilting, folding, erosion, and subsequent deposition and lithification of the various GC Super Group layers can only inspire complete and utter awe in the deep unimaginable time required for the occurrence of these events.

Combine that with yet another unconformity just about the Super Group and I just can't see how anyone can accept that this mass of formations and features could be explained by a mythic year. I also cannot understand why people want to take away the Grandeur of Creation and God by placing these events within time periods that puny humans can understand.

Edited by iceage, : No reason given.


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iceage 
Suspended Member (Idle past 5187 days)
Posts: 1024
From: Pacific Northwest
Joined: 09-08-2003


Message 91 of 202 (424579)
09-27-2007 2:17 PM
Reply to: Message 88 by CTD
09-27-2007 12:34 AM


Hey CTD that is one impressive rock plug - thanks for sharing it, it is pretty cool.

CTD writes:

If something like this were to happen underneath some horizontal rocks, what would the result look like?

Rock is largely an incompressible and brittle material. Therefore for a solid igneous rock like this to protrude into established sediments there would be lots of fracturing and material displacement.

Nevertheless as pointed out below this would not form an Angular Unconformity as the rock is igneous and not sedimentary.

As far as repositioning the established sedimentary rock to form a feature that would *appear* to be an Angular Unconformity is really just pie-in-the-sky wishful thinking. This sounds a bit like the non-evidence based theory the NJ mentioned before (actually I think the source was a prior poster here Faith). Keep in mind this theory is being posited by people that are not looking at the evidence and the data. This theory is just trying to invent some creative impossible events to make some preconceived notion somehow work. Also you would never find a YEC with a modicum of Geology knowledge promoting such a concept.

Here are a few reasons of the top why this idea does not work and does not conform to the data…..

  • The upper and lower components of a most Angular Unconformities are of a completely different material and method of deposition. This is because the time between each separate deposition is often separated by millions to 100’s of millions of years and the surrounding conditions that resulted in the erosion/deposition had changed. If the above theory was largely correct we would find most Angular Unconformities of the same material and might even be able to identify common strata in both upper and lower components. Note there are some unconformities of the similar material. Such Unconformities are rare and my guess is if you dated the upper and lower layer they would not be widely different in age.

  • Many Unconformities have recognizable erosion horizons and rounded eroded rock of the lower component (and other country rock) are found mixed in a matrix in the first few feet of the upper components. Look at these hi-res images of the famous Siccar point and you can see what I am talking about…

    http://www.geos.ed.ac.uk/undergraduate/field/siccarpoint/images.html

  • There is not usually fracturing in the sedimentary layers of an unconformity, at least not anymore than you would usually expect otherwise. As noted above, underground displacement of strata would entail significant fracturing and disturbance.

  • If solid or semi-solid sedimentary rock was sliding over each other you would not find nicely beveled surfaces like the image below. And just where did that extra shaved off material go?


    Click to enlarge

  • Rock formations moving around by each other deep in the earth under enormous pressures would generate some intense frictional heating which would be noted in the nature of the rock at the contact.

    CT writes:

    And you guys need to get down to NASA & take care of whoever let this slip out, BTW. Someone's not with the gameplan. We're supposed to have to rely on AIG for this kind of thing.

    Well NASA did publish that cool image but somehow I don’t think they are proposing it as some support for whacked-out theories anymore than they are planning to revert to an earth-centric cosmology.

    Let me just add that I think I would prefer a theory of Unconformity origin based on mischievous underground poltergeist rearranging strata just keep us busy than the one proposed :)

    Edited by iceage, : No reason given.


  • This message is a reply to:
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