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Author Topic:   Formations really do match detailed lab expts of sorting under rapid currents
Tranquility Base
Inactive Member


Message 92 of 130 (26341)
12-11-2002 5:54 PM
Reply to: Message 89 by edge
12-11-2002 4:04 PM


Edge
Edge writes:
How do you know what I am used to? I have seen this phenomenon in the geological record, probably thousands of times. How do you think this has escaped the notice of geologists for the last 200 years?
Are you talking of cross-bedding for example?
Show me where they cross true bedding joints.
In Berthault's video-tape they clearly do. We can only surmise that where paleocurrents reveal rapid depositon that the bedding planes in these cases are only apparent or are not what you would normally consider a bedding plane.
Not at all. As I have said, we see these things frequently (but not everywhere, just why is that?) in the geological record.
Our model has plenty of room for deposition under zero-flow too.

This message is a reply to:
 Message 89 by edge, posted 12-11-2002 4:04 PM edge has replied

Replies to this message:
 Message 93 by edge, posted 12-11-2002 8:06 PM Tranquility Base has replied

  
edge
Member (Idle past 1785 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 93 of 130 (26359)
12-11-2002 8:06 PM
Reply to: Message 92 by Tranquility Base
12-11-2002 5:54 PM


quote:
Originally posted by Tranquility Base:
Edge writes:
How do you know what I am used to? I have seen this phenomenon in the geological record, probably thousands of times. How do you think this has escaped the notice of geologists for the last 200 years?
Are you talking of cross-bedding for example?
I am tired of answering your questions when you refuse to answer mine. How do you know what I am used to? How do you think geologists have missed this phenomenon over the last 200 years?
quote:
Show me where they cross true bedding joints.
In Berthault's video-tape they clearly do. We can only surmise that where paleocurrents reveal rapid depositon that the bedding planes in these cases are only apparent or are not what you would normally consider a bedding plane.
Nope, you cannot see this. Please point out where cross laminations actually cut a bedding joint.
quote:
Not at all. As I have said, we see these things frequently (but not everywhere, just why is that?) in the geological record.
Our model has plenty of room for deposition under zero-flow too.
Non sequitur.

This message is a reply to:
 Message 92 by Tranquility Base, posted 12-11-2002 5:54 PM Tranquility Base has replied

Replies to this message:
 Message 94 by Tranquility Base, posted 12-11-2002 8:36 PM edge has replied

  
Tranquility Base
Inactive Member


Message 94 of 130 (26363)
12-11-2002 8:36 PM
Reply to: Message 93 by edge
12-11-2002 8:06 PM


It has not been completely missed by generations of geologists but you have so emphasized gradualism that I beleive most formations are automatically forced into stratum at a time interpretaitons.
So, is cross-bedding what you are talking about?

This message is a reply to:
 Message 93 by edge, posted 12-11-2002 8:06 PM edge has replied

Replies to this message:
 Message 97 by edge, posted 12-11-2002 11:53 PM Tranquility Base has not replied

  
wehappyfew
Inactive Member


Message 95 of 130 (26365)
12-11-2002 10:11 PM
Reply to: Message 91 by Tranquility Base
12-11-2002 5:41 PM


TB, I think you are comparing apples to oranges here:
TB writes:
but the vertical facies effect only occurs as the coastline migrates. In Julien's experiments you do not need migration to get vertical sorting.
I disagree strongly with the unneccessary dichotomy here. Vertical sorting in a prograding lamination/crossbed is a standard part of conventional sedimentology. Julien's flume work shows exactly what sedimentologists have known for decades. It shows how cross beds and other laminations build out along the direction of current. Julien has repeated the earlier work done by the half a dozen other researchers I listed in a previous post.
Julien's work does NOT show vertical facies changes, and it does NOT show that the superposition of crosscutting relationships is violated. The alternating layers of fine and coarse sand in the flume would be classified as a single facies of laminated sands or crossbedded sands. Several such layers can be seen in this photo:
The top middle shows a series of crossbed sets that truncate previous sets. Each of these is composed of laminated fine and coarse sands. Each individual crossbed set is strongly diachronous - that is, the laminations at one end were formed at a different time that those at the other end. To translate this to Julien's work, several of these laminations would be forming at the same time, and a lower one might form after an upper one at a different location in the same crossbed set. Julien's flume layers represents the formation of a single set of laminations comparable to the laminations in a single crossbed set.
Each time a set of crossbedded laminations intersects another set at an angle, it truncates it. This is a crosscutting relationship. It shows that all of the truncating laminations formed after all of the truncated ones. The photo of the Tapeats sandstone above shows several crossbeds that crosscut. From the few clear truncations visible, it might look like the dune sets that formed the crossbeds migrated to the left, thus the strata is older on the right, younger on the left. Each flat layer of conglomerate truncates the sand laminations below it, thus each conglomerate layer is younger than all the sand beds below it (and younger than the previous conglomerate below the sand crossbeds). There are several such sequences visible in the photo.
Nothing in Berthault's website show any evidence that such crosscutting relationships have been found to violate superposition, despite his many claims of having done so. For his scenario to be correct, the flat-lying conglomerate layers above must all form at the same time, yet the crosscutting relationships of the crossbeds clearly show this is impossible.
A vertical facies change is what constitutes a trangressive sequence. Sand overlain by silt overlain by shale overlain by limestone. Nothing in Berthault's website or Julien's flume experiments constitutes a vertical facies change. The alternation of fine and coarse sand is a single facies - laminated sandstone. The velocities in Julien's flume cannot deposit shale or lime mud or even coarse silt, so no facies change is possible. Even the conglomerate/coarse sand/fine sand visible in the photo above could not all be deposited by the same flow velocity. Even that limited micro-facies change from beach conglomerates to underwater sand dunes requires a significant change in current velocity. About 50 cm/s is low enough to begin the deposition of the smallest conglomerate, but that is high enough to erode a med/coarse sand. Not until velocity falls to about 1 cm/s would the fine sands be deposited, by which time the conglomerate would have long since dropped out.
Your claim... "In Julien's experiments you do not need migration to get vertical sorting" ... is true only WITHIN the facies.
In your last post:
TB writes:
but you have so emphasized gradualism that I beleive most formations are automatically forced into stratum at a time interpretaitons
Actually, the exact opposite is true. Most formations are recognized and even assumed to be diachronous unless proven otherwise. Your geologic knowledge appears to remain at the cartoon/kindergarten level. Even the intro level geology texts cover the diachronous nature of most strata.

This message is a reply to:
 Message 91 by Tranquility Base, posted 12-11-2002 5:41 PM Tranquility Base has not replied

Replies to this message:
 Message 96 by TrueCreation, posted 12-11-2002 10:28 PM wehappyfew has not replied

  
TrueCreation
Inactive Member


Message 96 of 130 (26368)
12-11-2002 10:28 PM
Reply to: Message 95 by wehappyfew
12-11-2002 10:11 PM


"Nothing in Berthault's website show any evidence that such crosscutting relationships have been found to violate superposition, despite his many claims of having done so."
--What really would be Berhault's accomplishment by violating the principle of superposition? I am slightly confused as to what exactly the issue at hand is here.
--And I had the impression that superposition is a principle in sedimentology which is only applicable in vertical successions. Unless ofcourse there was the scneario in geomorphologic influence where an earlier deposited stratum be lapped over a younger one.
--By the way, my desktop is working now so I'll be continuing some of the other threads I've been absent from recently.
------------------
[This message has been edited by TrueCreation, 12-11-2002]

This message is a reply to:
 Message 95 by wehappyfew, posted 12-11-2002 10:11 PM wehappyfew has not replied

Replies to this message:
 Message 98 by edge, posted 12-11-2002 11:57 PM TrueCreation has not replied

  
edge
Member (Idle past 1785 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 97 of 130 (26370)
12-11-2002 11:53 PM
Reply to: Message 94 by Tranquility Base
12-11-2002 8:36 PM


quote:
Originally posted by Tranquility Base:
It has not been completely missed by generations of geologists but you have so emphasized gradualism that I beleive most formations are automatically forced into stratum at a time interpretaitons.
Not at all. I simply do not ascribe rapid deposition to ALL systems as you require. I have seen and understand rapidly deposited sands that form beaches etc. The point is that the sands were probably deposited many times before they were preserved by overlying deposits. Just as todays beaches will sometime look like those in the geological record if they are part of a transgressive sequence.
On the other hand, if you allow what you call zero flow deposition for the Pierre Shale, for instance, you are instantly out of a one year flood scenario.
quote:
So, is cross-bedding what you are talking about?
Basically, yes. I'm trying to think if there are exceptions but can't come up with any right now. What you are seeing in the experiments are cross beds.

This message is a reply to:
 Message 94 by Tranquility Base, posted 12-11-2002 8:36 PM Tranquility Base has not replied

  
edge
Member (Idle past 1785 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 98 of 130 (26372)
12-11-2002 11:57 PM
Reply to: Message 96 by TrueCreation
12-11-2002 10:28 PM


quote:
Originally posted by TrueCreation:
"Nothing in Berthault's website show any evidence that such crosscutting relationships have been found to violate superposition, despite his many claims of having done so."
--What really would be Berhault's accomplishment by violating the principle of superposition? I am slightly confused as to what exactly the issue at hand is here.
The issue is superpostion as defined by mainstream science, not superposition as defined by Berthault.
quote:
--And I had the impression that superposition is a principle in sedimentology which is only applicable in vertical successions. Unless ofcourse there was the scneario in geomorphologic influence where an earlier deposited stratum be lapped over a younger one.
Every sediment must overlay an older sediment at the same location. If that bed overlies something younger in another location, then it is even younger at that location.

This message is a reply to:
 Message 96 by TrueCreation, posted 12-11-2002 10:28 PM TrueCreation has not replied

Replies to this message:
 Message 99 by Tranquility Base, posted 12-12-2002 12:06 AM edge has replied

  
Tranquility Base
Inactive Member


Message 99 of 130 (26373)
12-12-2002 12:06 AM
Reply to: Message 98 by edge
12-11-2002 11:57 PM


At the risk of repeating myself here is what Berthault's experiments show in black and white (OK, blue and white):
t=0
*********
&&&&&&&&&&&&
t=t1
************
&&&&&&&&&&&&&&&
t=t2
^^^^^
***************
&&&&&&&&&&&&&&&&&&
The right-most parts of the &-layer occur after some of the ^^^^ layer. The mechanim turns out to be hydrological sorting and preferential friction with the current layer at X. Note that sorting neatly puts new ^^^, new *** and new &&& all in a line. The time-boundary is not the bedding-planes but crosses it and may be evident as cross-bedding I imagine.
[This message has been edited by Tranquility Base, 12-12-2002]

This message is a reply to:
 Message 98 by edge, posted 12-11-2002 11:57 PM edge has replied

Replies to this message:
 Message 100 by wehappyfew, posted 12-12-2002 8:02 AM Tranquility Base has replied
 Message 101 by edge, posted 12-12-2002 5:43 PM Tranquility Base has replied

  
wehappyfew
Inactive Member


Message 100 of 130 (26397)
12-12-2002 8:02 AM
Reply to: Message 99 by Tranquility Base
12-12-2002 12:06 AM


TB writes:
The time-boundary is not the bedding-planes but crosses it and may be evident as cross-bedding I imagine.
Imagination is a poor substitute for actually looking at rocks and sediments. The alternating bands of fine and coarse sand that result from your illustration are called "laminations". No one would confuse them with cross-bedding because a crossbed is composed of many individual laminations. It is the change in grain sizes that makes the horizontal laminatons visible. A line drawn through the surface of deposition would indeed cross the individual laminations, but would not leave a crossbed unless deposition was interrupted or changed in character. An interruption leaves a change in grain size at an angle to these laminations. Without any interruptions or changes, the time boundary is not even visible. Only the horizontal laminations have sufficient contrast to be visible.
As I explained previously, these laminations are very common, and frequently intersect each other in a sequential manner to form crossbeds. The sequence is apparent by examining the cross-cutting relationships between each set of laminations.
Other forms of laminations are also possible, and I wouldn't be suprised if Julien re-created then in his flume experiments. Think of the horizontal laminations as the simplest configuration possible. Under a different set of conditions, rippled laminations might form, for example.

This message is a reply to:
 Message 99 by Tranquility Base, posted 12-12-2002 12:06 AM Tranquility Base has replied

Replies to this message:
 Message 102 by Tranquility Base, posted 12-15-2002 7:08 PM wehappyfew has not replied

  
edge
Member (Idle past 1785 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 101 of 130 (26449)
12-12-2002 5:43 PM
Reply to: Message 99 by Tranquility Base
12-12-2002 12:06 AM


quote:
Originally posted by Tranquility Base:
At the risk of repeating myself here is what Berthault's experiments show in black and white (OK, blue and white):
t=0
*********
&&&&&&&&&&&&
t=t1
************
&&&&&&&&&&&&&&&
t=t2
^^^^^
***************
&&&&&&&&&&&&&&&&&&
The right-most parts of the &-layer occur after some of the ^^^^ layer. The mechanim turns out to be hydrological sorting and preferential friction with the current layer at X. Note that sorting neatly puts new ^^^, new *** and new &&& all in a line. The time-boundary is not the bedding-planes but crosses it and may be evident as cross-bedding I imagine.
The problem is that the sloping line is now your time-stratigraphic horizon. The bedding is not time-bound as wehappy and I have been saying ad nauseum. The sloping layers will be laminai that are readily recognized by geologists in the field.
{Fixed quote structure - AM}
[This message has been edited by Adminnemooseus, 12-12-2002]

This message is a reply to:
 Message 99 by Tranquility Base, posted 12-12-2002 12:06 AM Tranquility Base has replied

Replies to this message:
 Message 103 by Tranquility Base, posted 12-15-2002 8:02 PM edge has replied

  
Tranquility Base
Inactive Member


Message 102 of 130 (26670)
12-15-2002 7:08 PM
Reply to: Message 100 by wehappyfew
12-12-2002 8:02 AM


Wehappy
wehappy writes:
Imagination is a poor substitute for actually looking at rocks and sediments. The alternating bands of fine and coarse sand that result from your illustration are called "laminations". No one would confuse them with cross-bedding because a crossbed is composed of many individual laminations.
I never confused that at all. The laminations are micro-layerings. During deposition under rapid flow, the bedding-planes are not time-boundaries and instead the time-boundaries I'm talking about cut across the laminations (see my 'graphic' above).
A line drawn through the surface of deposition would indeed cross the individual laminations, but would not leave a crossbed unless deposition was interrupted or changed in character.
That's perhaps the general mainstream understanding (or perhaps your expectaiton). Bertahult and Julien's work suggests that cross-bedding might actually be evidence of cross-bedding plane time-boundaries formed during non-zero flow.
But I'm no expert on cross-bedding. Have you carefully read where cross-bedding entered this thread? The issue came up when Edge mentioned that he can easily see the time-bpoundaries that cut across bedding planes. I asked whether that evidence includes cross-bedding and the debate is no over whether such time boundaries cross'genuine' bedding planes. I simply can't work out whetehr Edge thinks corss-bedding crosses bedding planes or not and whether he thinks it is Berhault's mecahnism or not. So please don't lecture me on lack of knowledge etc etc. I proposed something very sensible on the basis of Edge's comment and he is responding cryptically. I suspect that cross-bedding is precisely evidence of Bertahult's mechanism.
An interruption leaves a change in grain size at an angle to these laminations. Without any interruptions or changes, the time boundary is not even visible. Only the horizontal laminations have sufficient contrast to be visible.
I think if you actaully saw Berthaults video tape you and saw how rpaid flow genrates mulitple layers simultaneously you would probabaly agree that it is unlikely that this could occur with nicely continuing layers with large time gaps inbetween the time-boundaries.
As I explained previously, these laminations are very common, and frequently intersect each other in a sequential manner to form crossbeds. The sequence is apparent by examining the cross-cutting relationships between each set of laminations.
I agree. But the sorting mechanism belies a rapid current. Do you deny that cross-bedding speaks of currents? Cross-bedding itslef is a paleocurrent measure and strongly suggests rapid formaiton of such beds.
Other forms of laminations are also possible, and I wouldn't be suprised if Julien re-created then in his flume experiments. Think of the horizontal laminations as the simplest configuration possible. Under a different set of conditions, rippled laminations might form, for example.
No problem.
[This message has been edited by Tranquility Base, 12-15-2002]

This message is a reply to:
 Message 100 by wehappyfew, posted 12-12-2002 8:02 AM wehappyfew has not replied

  
Tranquility Base
Inactive Member


Message 103 of 130 (26676)
12-15-2002 8:02 PM
Reply to: Message 101 by edge
12-12-2002 5:43 PM


Edge writes:
The problem is that the sloping line is now your time-stratigraphic horizon. The bedding is not time-bound as wehappy and I have been saying ad nauseum. The sloping layers will be laminai that are readily recognized by geologists in the field.
Why is that a 'problem'. Why do you keep telling me that this is what you're telling me when it is I that have maintained this since the very first post in this thread?
Tranquilty in the first post of this thread writes:
The lower layers at the end of the flow direction are formed after much of the top layers at the start of the flow area but the layers are trackable from start to end.
Your sloping lines will produce laminai. I essentailly agree but wha tare these laminai identifiable by? Composition? 3D Texturing? What? Is this an example of cross-bedding? Do these sloping laminai, easily recognized by the pros, cross bedding planes that separate compostionally differnetiated laminai?
Key point: Are you agreeing with us or not? Why make this all such a mystery?
[This message has been edited by Tranquility Base, 12-15-2002]

This message is a reply to:
 Message 101 by edge, posted 12-12-2002 5:43 PM edge has replied

Replies to this message:
 Message 104 by edge, posted 12-16-2002 1:28 PM Tranquility Base has replied

  
edge
Member (Idle past 1785 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 104 of 130 (26794)
12-16-2002 1:28 PM
Reply to: Message 103 by Tranquility Base
12-15-2002 8:02 PM


quote:
Originally posted by Tranquility Base:
Edge writes:
The problem is that the sloping line is now your time-stratigraphic horizon. The bedding is not time-bound as wehappy and I have been saying ad nauseum. The sloping layers will be laminai that are readily recognized by geologists in the field.
Why is that a 'problem'. Why do you keep telling me that this is what you're telling me when it is I that have maintained this since the very first post in this thread?
Because you don’t seem to treat sediments below the time line as older than those above. You seem to think that being vertically higher means younger. This is not the case. You repeatedly tell us that you understand this but you clearly do not.
quote:
Tranquilty in the first post of this thread writes:
The lower layers at the end of the flow direction are formed after much of the top layers at the start of the flow area but the layers are trackable from start to end.
Just as I have said. You are saying the lower layers above the time line should be older than the higher sediments above the time line according to us. This is not so.
quote:
Your sloping lines will produce laminai. I essentailly agree but wha tare these laminai identifiable by? Composition? 3D Texturing? What? Is this an example of cross-bedding?
They are discontinuities in the depositional sequence. Compositional and/or textural. Depends on the environment.
quote:
Do these sloping laminai, easily recognized by the pros, cross bedding planes that separate compostionally differnetiated laminai?
Sometimes.
quote:
Key point: Are you agreeing with us or not? Why make this all such a mystery?
I’m not sure who ‘we’ is, but basically, no. I disagree entirely with the meaning and significance of the observations. This is basic geology and Berthault has taken a common, but non-intuitive geological observation and turned it into an issue that does not exist, but can be used to deceive the layman.

This message is a reply to:
 Message 103 by Tranquility Base, posted 12-15-2002 8:02 PM Tranquility Base has replied

Replies to this message:
 Message 105 by Tranquility Base, posted 12-16-2002 9:46 PM edge has replied

  
Tranquility Base
Inactive Member


Message 105 of 130 (26914)
12-16-2002 9:46 PM
Reply to: Message 104 by edge
12-16-2002 1:28 PM


Edge
Here is the point of all of this.
If you tracked a stratum for 800 km (let's say a small group of starta since that is probably unrealistic) would you normally assume that there could be a 70 million year time differential between one end and the other? I doubt it.
Progradation is one thing, applying it, and understanding the mechanism, for individual strata is another. Showing that such progradation starta can occur under rapid currents without neccesarily requiring sea-level changes is another thing again.
These are the novel features of Berhault and Julien's experiments that you pretend are not novel or significantly expanded on.

This message is a reply to:
 Message 104 by edge, posted 12-16-2002 1:28 PM edge has replied

Replies to this message:
 Message 106 by edge, posted 12-17-2002 12:09 AM Tranquility Base has replied

  
edge
Member (Idle past 1785 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 106 of 130 (26928)
12-17-2002 12:09 AM
Reply to: Message 105 by Tranquility Base
12-16-2002 9:46 PM


quote:
Originally posted by Tranquility Base:
Here is the point of all of this.
If you tracked a stratum for 800 km (let's say a small group of starta since that is probably unrealistic) would you normally assume that there could be a 70 million year time differential between one end and the other? I doubt it.
Who does this? I never make such assumptions.
quote:
Progradation is one thing, applying it, and understanding the mechanism, for individual strata is another. Showing that such progradation starta can occur under rapid currents without neccesarily requiring sea-level changes is another thing again.
These are the novel features of Berhault and Julien's experiments that you pretend are not novel or significantly expanded on.
Sorry, but they aren't. If you think they are, you have been deceived by your professional creationists. I have an almost thirty year old text that talks exactly about this phenomenon. The only people who don't understand this are creationists. And thus it will always be.

This message is a reply to:
 Message 105 by Tranquility Base, posted 12-16-2002 9:46 PM Tranquility Base has replied

Replies to this message:
 Message 107 by Tranquility Base, posted 12-17-2002 7:53 AM edge has replied

  
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