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Author Topic:   The Light Time Problem
Tanypteryx
Member
Posts: 4443
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 5.0


(1)
Message 256 of 278 (895423)
06-26-2022 6:46 PM
Reply to: Message 255 by Astrophile
06-26-2022 5:38 PM


Re: SHOW US, candle2!
Excuse me for asking, but has this got anything to do with the light-time problem?
I think it was that very last bit.
quote
If you feel safe in your current view of the world,
then by all means don't do anything that might
enlighten you.
  —candyass2

Stop Tzar Vladimir the Condemned!

What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 255 by Astrophile, posted 06-26-2022 5:38 PM Astrophile has replied

Replies to this message:
 Message 257 by Astrophile, posted 06-30-2022 4:54 PM Tanypteryx has not replied

  
Astrophile
Member (Idle past 154 days)
Posts: 92
From: United Kingdom
Joined: 02-10-2014


(1)
Message 257 of 278 (895472)
06-30-2022 4:54 PM
Reply to: Message 256 by Tanypteryx
06-26-2022 6:46 PM


Re: SHOW US, candle2!
Tanypteryx writes:
I think it was that very last bit.

quote
If you feel safe in your current view of the world,
then by all means don't do anything that might
enlighten you.
—candyass2
Thank-you. I hadn't noticed that bit.

This message is a reply to:
 Message 256 by Tanypteryx, posted 06-26-2022 6:46 PM Tanypteryx has not replied

  
Dredge
Member (Idle past 100 days)
Posts: 2850
From: Australia
Joined: 09-06-2016


Message 258 of 278 (899224)
10-10-2022 8:44 PM
Reply to: Message 36 by dwise1
04-16-2022 4:01 PM


dwise1 writes:
Radiometric dating on rock is how long ago it solidified from being molten.
Radiometric dating cannot be performed on sedimentary rock since it is ground down and recycled older rock, so radiometric dating would just get the age of bit of old rock tested. However, we can tell which layers are older than others by the order in which they are stacked. We can also establish dates for layers from igneous intrusions which bracket them in. Therefore we can determine the age of a particular layer.
But the sedimentary rock could be much younger than the surrounding igneous rock.
A flood could leave a sedimentary layer-cum-rock around some igneous rocks millions-billions of years after said igneous rocks were formed.

This message is a reply to:
 Message 36 by dwise1, posted 04-16-2022 4:01 PM dwise1 has not replied

Replies to this message:
 Message 259 by ringo, posted 10-10-2022 10:12 PM Dredge has replied

  
ringo
Member (Idle past 438 days)
Posts: 20940
From: frozen wasteland
Joined: 03-23-2005


(1)
Message 259 of 278 (899235)
10-10-2022 10:12 PM
Reply to: Message 258 by Dredge
10-10-2022 8:44 PM


Dredge writes:
But the sedimentary rock could be much younger than the surrounding igneous rock.
How do you figure a sedimentary layer managed to sneak UNDER an older igneous layer?

"Oh no, They've gone and named my home St. Petersburg.
What's going on? Where are all the friends I had?
It's all wrong, I'm feeling lost like I just don't belong.
Give me back, give me back my Leningrad."
-- Leningrad Cowboys

This message is a reply to:
 Message 258 by Dredge, posted 10-10-2022 8:44 PM Dredge has replied

Replies to this message:
 Message 260 by dwise1, posted 10-10-2022 10:45 PM ringo has seen this message but not replied
 Message 261 by Dredge, posted 10-11-2022 8:15 PM ringo has replied

  
dwise1
Member
Posts: 5949
Joined: 05-02-2006
Member Rating: 5.2


(3)
Message 260 of 278 (899238)
10-10-2022 10:45 PM
Reply to: Message 259 by ringo
10-10-2022 10:12 PM


You forget that he's hanging upside down in Australia.
He doesn't know up from down, let alone which way is up.

This message is a reply to:
 Message 259 by ringo, posted 10-10-2022 10:12 PM ringo has seen this message but not replied

  
Dredge
Member (Idle past 100 days)
Posts: 2850
From: Australia
Joined: 09-06-2016


Message 261 of 278 (899313)
10-11-2022 8:15 PM
Reply to: Message 259 by ringo
10-10-2022 10:12 PM


ringo writes:
How do you figure a sedimentary layer managed to sneak UNDER an older igneous layer?
Between the sedimentary layer that contains a fossil and the igneous layer below could be hundreds of meters of other sedimentary rock layers ... which means that fossil-layer could have formed a very long time after the igneous layer.
But I guess general geological patterns emerge, which is where index fossils come into play.

This message is a reply to:
 Message 259 by ringo, posted 10-10-2022 10:12 PM ringo has replied

Replies to this message:
 Message 262 by ringo, posted 10-11-2022 10:22 PM Dredge has not replied
 Message 263 by dwise1, posted 10-11-2022 10:42 PM Dredge has replied

  
ringo
Member (Idle past 438 days)
Posts: 20940
From: frozen wasteland
Joined: 03-23-2005


(1)
Message 262 of 278 (899320)
10-11-2022 10:22 PM
Reply to: Message 261 by Dredge
10-11-2022 8:15 PM


Dredge writes:
Between the sedimentary layer that contains a fossil and the igneous layer below could be hundreds of meters of other sedimentary rock layers ... which means that fossil-layer could have formed a very long time after the igneous layer.
I specified that the igneous layer is ON TOP of the sedimentary layer. Try again.

"Oh no, They've gone and named my home St. Petersburg.
What's going on? Where are all the friends I had?
It's all wrong, I'm feeling lost like I just don't belong.
Give me back, give me back my Leningrad."
-- Leningrad Cowboys

This message is a reply to:
 Message 261 by Dredge, posted 10-11-2022 8:15 PM Dredge has not replied

  
dwise1
Member
Posts: 5949
Joined: 05-02-2006
Member Rating: 5.2


(2)
Message 263 of 278 (899323)
10-11-2022 10:42 PM
Reply to: Message 261 by Dredge
10-11-2022 8:15 PM


As usual, you ignore the whole picture.
Of course your pathological willful stupidity will keep you from learning, so this is for others who will read this (eg, online right now are four members and 153 visitors):
  • Sedimentary layers can be dated relatively based on the Law of Superposition:
    quote:
    In its plainest form, it states that in undeformed stratigraphic sequences, the oldest strata will lie at the bottom of the sequence, while newer material stacks upon the surface to form new deposits over time. This is paramount to stratigraphic dating, which requires a set of assumptions, including that the law of superposition holds true and that an object cannot be older than the materials of which it is composed.
  • Radiometric dating determines how long ago the rock last solidified after having been completely molten.:
    • Igneous rock as is found in volcanic ash, lava flows, and igneous intrusions had been melted and so can be dated with radiometric dating methods.
    • Sedimentary rock is composed of ground-up rocks so radiometric dating methods will not work on them, but rather would yield older dates from the component older rocks.
    That means that you can get absolute ages for igneous rocks but not for sedimentary rocks.
  • We can bracket in a range of absolute values for sedimentary layers (ie, determine its age to be with a range between a younger and an older age). This is typically done through igneous layers and igneous intrusions:
    • If the sedimentary layer is above an igneous layer that had formed on the surface (important point; see below), then the sedimentary layer is younger than the underlying igneous layer. The age of the igneous layer would give us an upper bound on the sedimentary layer's age.
    • If the sedimentary layer is below an igneous layer that had formed on the surface (important point; see below), then the underlying sedimentary layer is older than the overlying igneous layer. The age of the igneous layer would give us an lower bound on the sedimentary layer's age.
    • If the sedimentary layer is between two igneous layers that had formed on the surface (important point; see below), then those two igneous layers bracket in the age of that sedimentary layer: it is younger than the older igneous layer and older than the younger igneous layer.
      Note that that bracketing between igneous layers can be constructed from findings at two different sites as long as the sedimentary layer can be determined to be the same layer. This is determined by comparing the characteristics of the layer at the two sites (eg, composition, index fossils) as well as its relative position between other layers.
    • If a vertical igneous intrusion is found through another layer, then that means that that layer had to already exist before the intrusion. Hence, that intrusion would be younger than the layer and, of course, the layer would be older than the intrusion. In addition, an intrusion could extend through multiple layers, thus providing a lower bound on those layers' ages (ie, they'd all be older than the intrusion).
    • It is possible for an intrusion to be horizontal, such that it forces itself between two pre-existing older layers. That would make the layers above and below a horizontal intrusion older than that intrusion.
      This is the important point I alerted you to above:
      This raises the question of how to tell whether an igneous layer had formed on the surface and then had more layers deposited on it, or had formed as a horizontal intrusion. Understand that the intense heat of that molten lava would have affected the pre-existing rock that came in contact with it. For example, in the Badlands of North Dakota, I found igneous intrusions into sandstone. Right along the contact between the sandstone and the intrusion the heat had changed the sandstone into a layer of sandy crust about a quarter-inch thick. It was very obvious and easy to see.
      In the case of the lower layer, both a surface lava flow and a horizontal intrusion would have the same effect due to intense heat along that contact. In the case of the upper layer, only a horizontal intrusion would have changed the upper layer along the contact due to intense heat. A surface lava flow would have solidified and cooled down before the overlying layer would have started to form, so the overlying layer would not be affected by the heat that is no longer present.
  • The bracketing of sedimentary layers between igneous layers could involve multiple sedimentary layers. In that case, relative dating between those layers as well as indicators of how rapidly they formed (eg, layers with large particles indicate rapid depositation and lack of large particles slow depositation) can be used to assign each layer its own time period within that range of ages.
  • Also, igneous bracketing at different sites can affect different sedimentary layers within that group of layers as well as provide comparison and verification of the igneous dates obtained.
But I guess general geological patterns emerge, which is where index fossils come into play.
Since you are a creationist, I can smell this typical stupid creationist "objection" coming: "Fossils are dated by their layers and layers are dated by their fossils, so it's nothing but circular reasoning."
No, that is most definitely not true. We see above how layers are dated.
Index fossils are just one means of identifying which layer we're looking at, plus those index fossils are very common ones and not the ones we're dating.
I explained that before to candle2 in this same topic, my Message 36 reply to his Message 30 (actually, your Message 258 that spawn your current fit of confusion was a "reply" to that same Message 36, excerpted here with a few typographical corrections):
DWise1 writes:
candle2 writes:
Also, fossils are dated by the strata that they
are found in, and the strata is dated by the
fossils they contain.
Yes, and? By the way you say that means that you are insinuating circular reasoning. Same dishonest creationist lie, hasn't changed a bit.
Radiometric dating on rock is how long ago it solidified from being molten.
Radiometric dating cannot be performed on sedimentary rock since it is ground down and recycled older rock, so radiometric dating would just get the age of bits of old rock tested. However, we can tell which layers are older than others by the order in which they are stacked. We can also establish dates for layers from igneous intrusions which bracket them in. Therefore we can determine the age of a particular layer.
Fossils cannot be dated directly (excluding organic specimens). For one thing, if you melt the fossil in order to "restart its clock", then you have destroyed that fossil -- if it's a fossil, it hasn't been melted, so no radiometrically dating a fossil. Fossils result from burial and so are most commonly found in sedimentary rock, but we can arrive at a date for the layer it's found in as described above (extremely important that you don't just pull a fossil out of the ground and carry it to a museum).
So how do we identify a layer here to be part of that other layer way over there?
In geology it's done with identifying characteristics which have been determined empirically, which includes index fossils. However, many of those index fossils are microscopic, eg diatom shells which evolve over time. Fossils such as the ones that we are interested in (eg, dinos) are not used as index fossils. Thus the fossils identifying the stratum (from which we know its age) are not the same as the fossils that get their age from which stratum they're in. There is no circular reasoning here.
Hope I was able to nip that one in the bud. But then you do never fail to disappoint.
 

This message is a reply to:
 Message 261 by Dredge, posted 10-11-2022 8:15 PM Dredge has replied

Replies to this message:
 Message 264 by Dredge, posted 10-11-2022 11:05 PM dwise1 has replied

  
Dredge
Member (Idle past 100 days)
Posts: 2850
From: Australia
Joined: 09-06-2016


(1)
Message 264 of 278 (899324)
10-11-2022 11:05 PM
Reply to: Message 263 by dwise1
10-11-2022 10:42 PM


Believe it or not, I'm not an expert in geology or atomic dating, so thank you for the information.

This message is a reply to:
 Message 263 by dwise1, posted 10-11-2022 10:42 PM dwise1 has replied

Replies to this message:
 Message 265 by dwise1, posted 10-11-2022 11:42 PM Dredge has replied

  
dwise1
Member
Posts: 5949
Joined: 05-02-2006
Member Rating: 5.2


(1)
Message 265 of 278 (899327)
10-11-2022 11:42 PM
Reply to: Message 264 by Dredge
10-11-2022 11:05 PM


It's all common knowledge. Plus things that one can work out based on how things work. Or asking the right questions and then researching for the answer. Anybody who has given it any serious thought would have come up with the same.
For example, while driving up to Lake Arrowhead (going from an elevation of 100 ft to one mile) for a father-son event, I was regarding the exposed roadside geology on display when a question occurred to me:
Since sedimentary layers (of which I was seeing a lot) consists of older rock that had been ground up and recycled, exactly how are they dated?
I mean, if you date them directly, then you should get a much older age because they consist of much older rock, right?
Since at that time (1994) we were just beginning to get access to the Internet, we didn't have the online resources yet, so I hit the university library. That is when I learned about the use of igneous layers and intrusions as "tie points".
The purpose of questions is to point us to the direction for finding the answer. And in science the best thing you can find in that answer is more questions. That way, we find paths to keep learning.
Using questions in order to intimidate or prevent discussion or to otherwise weaponize them is a serious abuse. That is how creationists typically abuse questions.

This message is a reply to:
 Message 264 by Dredge, posted 10-11-2022 11:05 PM Dredge has replied

Replies to this message:
 Message 266 by Dredge, posted 10-12-2022 10:09 PM dwise1 has replied

  
Dredge
Member (Idle past 100 days)
Posts: 2850
From: Australia
Joined: 09-06-2016


Message 266 of 278 (899381)
10-12-2022 10:09 PM
Reply to: Message 265 by dwise1
10-11-2022 11:42 PM


dwise1 writes:
Since sedimentary layers (of which I was seeing a lot) consists of older rock that had been ground up and recycled, exactly how are they dated?
I mean, if you date them directly, then you should get a much older age because they consist of much older rock, right?
Right. Furthermore, I imagine sedimentary rock could contain a mish-mash of particles of vastly varying ages - for example, some particles could be only thousands of years old while other particles could be billions of years old.

This message is a reply to:
 Message 265 by dwise1, posted 10-11-2022 11:42 PM dwise1 has replied

Replies to this message:
 Message 267 by AZPaul3, posted 10-12-2022 10:21 PM Dredge has replied
 Message 268 by Tanypteryx, posted 10-12-2022 10:30 PM Dredge has replied
 Message 270 by dwise1, posted 10-13-2022 2:01 AM Dredge has replied

  
AZPaul3
Member
Posts: 8552
From: Phoenix
Joined: 11-06-2006
Member Rating: 4.9


Message 267 of 278 (899385)
10-12-2022 10:21 PM
Reply to: Message 266 by Dredge
10-12-2022 10:09 PM


Furthermore, I imagine sedimentary rock could contain a mish-mash of particles of vastly varying ages - for example, some particles could be only thousands of years old while other particles could be billions of years old.
And you imagine god and meat-crackers and all kinds of other wrong things. So now that you know you are wrong about the particle mix how does this change things?

Stop Tzar Vladimir the Condemned!

This message is a reply to:
 Message 266 by Dredge, posted 10-12-2022 10:09 PM Dredge has replied

Replies to this message:
 Message 269 by Dredge, posted 10-13-2022 1:49 AM AZPaul3 has replied

  
Tanypteryx
Member
Posts: 4443
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 5.0


Message 268 of 278 (899387)
10-12-2022 10:30 PM
Reply to: Message 266 by Dredge
10-12-2022 10:09 PM


for example, some particles could be only thousands of years old while other particles could be billions of years old.
Well, the rocks would have to be at least as old as the particles that make them up, and I don't think there are any exposed sedimentary rocks that are only thousands of years old. And I also don't think that any particles from exposed sedimentary rocks have ever been dated at only thousands of years old. And yes, we can do radiometric dating on individual particles using mass spectrometry.

Stop Tzar Vladimir the Condemned!

What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 266 by Dredge, posted 10-12-2022 10:09 PM Dredge has replied

Replies to this message:
 Message 272 by Dredge, posted 10-13-2022 3:13 AM Tanypteryx has not replied

  
Dredge
Member (Idle past 100 days)
Posts: 2850
From: Australia
Joined: 09-06-2016


Message 269 of 278 (899394)
10-13-2022 1:49 AM
Reply to: Message 267 by AZPaul3
10-12-2022 10:21 PM


AZPaul3 writes:
So now that you know you are wrong about the particle mix how does this change things?
I don't know⁶.

This message is a reply to:
 Message 267 by AZPaul3, posted 10-12-2022 10:21 PM AZPaul3 has replied

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dwise1
Member
Posts: 5949
Joined: 05-02-2006
Member Rating: 5.2


(1)
Message 270 of 278 (899395)
10-13-2022 2:01 AM
Reply to: Message 266 by Dredge
10-12-2022 10:09 PM


Furthermore, I imagine sedimentary rock could contain a mish-mash of particles of vastly varying ages - ...
Correct in general, but there's are a few things to keep in mind. BTW, the next thing you wrote alerted me to the need for the following:
  • The age of a layer is how long ago it had formed:
    • For an igneous layer, that would be when the molten rock (eg, lava) had solidified.
    • For a sedimentary layer, that would be when the material, usually a collection of rock particles, was deposited.
    • For metamorphic rock, I'm not sure since I haven't worked through this case. It would have an age for when it formed originally as a layer at which time it would have been either igneous or sedimentary. But then it was subjected to forces (eg, heat, pressure) which changed it, thus metamorphizing it into a different kind of rock. I do not know whether there are dating methods for determining when that metamorphic event happened.
      Therefore, we won't discuss dating a metamorphic layer. Nor should we here since the question is about sedimentary layers.
  • The material making up the sedimentary layer must be older than that layer. Here is why:
    • The material that makes up a sedimentary layer has to already exist. That means that all that material, every single particle of it, has to be older than the layer they form. Using the cake analogy, you can't bake a cake with flour that won't be milled for another month yet; the flour has to have been milled before going into the cake.
    • The layers that were the source of that material had to have formed before their material was available for forming the new sedimentary layer. Therefore, those layers had to have been older than the new sedimentary layer.
    • Parts of those older layers had to have broken up and ground up by forces such as erosion. That takes time, usually a lot of time.
      A typical scenario would be:
      1. The older layers form. Usually they will be buried under later layers, but occasionally some of them remain as the surface (in which case, skip Step 2).
        BTW, in order to lithify (ie, become rock -- Greek: λιθος = rock) the layer must be buried. If it is not buried, then it just remains dirt (or soil) which will get transported away with the rain or wind (unless trapped by vegetation's root systems) in the quickest form of erosion I can think of.
        You know, actually a layer that doesn't get buried and lithifies but rather remains the surface ... that doesn't qualify as a sedimentary layer. It's just unincorporated particles waiting around to be transported or buried to form a layer. We don't have to worry about it (though I had written a lot of the following before this realization and don't have time to edit it).
      2. Over time, those upper layers erode away, exposing those older layers. Or else (and much more commonly I would think) erosion creates a cliff (eg, the sides of a hill or of a river valley) which exposes part of those layers on the cliff face.
      3. Whether through being exposed by earlier erosion or having remained the surface, erosion breaks off pieces of those older layers and then breaks them down into smaller and smaller particles which then get transported away by flowing water or winds (eg, the beaches of Southern California where granite mountains get broken apart and ground up into smaller particles that are transported by streams and rivers out to the ocean where they form the quartz sand on our beaches; the coral reefs around Oahu getting eroded down by the ocean waves to form the coral sand of Waikiki).
        BTW, when geologists examine sandstone, they are able to tell whether that sand had been deposited by wind or by water.
      4. Well, finally the particles get transported to where they form the new sedimentary layer.
    • Each of those steps take time, a lot of time. So taking the example of just a single old layer: you have the old layer forming which takes time, then you have it being buried (or not, but it won't lithify unless it is buried) which takes time. Then you have to expose it again through erosion, which takes more time. Then erosion on those exposed parts of the layer needs to break it up into particles, which takes more time. Then those particles need to get broken down into smaller particles, hence even more time. And finally those particles need to be transported to where they can form a new layer -- you guessed it: more time.
    • What we end up with is the obvious fact that the particles that comprise a new sedimentary layer must be older than that layer. Most commonly much older by an order of millions of years older.
So then, yes, the ages of individual particles within a sedimentary layer would be a vastly varying mish-mash. But we do know that all those ages have to be greater than the age of the new layer composed of those particles. Often vastly older.
... - for example, some particles could be only thousands of years old while other particles could be billions of years old.
If not for your protestations that you are an OEC and not a YEC, I would say that it looks suspiciously like you are trying to set up a YEC claim.
No, "only thousands of years old" is very unlikely. The time it would have taken for each step of the process taken sequentially as I delineated it above would have to have been far greater than that.
I think you may be getting too close to veering off the road and into the weeds there. Keep your eyes on the road, your hand upon the wheel.

This message is a reply to:
 Message 266 by Dredge, posted 10-12-2022 10:09 PM Dredge has replied

Replies to this message:
 Message 271 by Dredge, posted 10-13-2022 3:12 AM dwise1 has replied

  
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