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Author Topic:   Non-marine sediments
Tranquility Base
Inactive Member


Message 1 of 221 (9656)
05-15-2002 1:26 AM


Are there any geologists out there who can tell me something about the non-marine sediments in the geological column? How thick can fossil bearing non-marine sedimentary beds be and how conformable (= continuously parallel stacked) are they? How conformable are they with the interfacing marine beds?

The reason I'm asking is that I'm a YEC and I'm often making statements about alternating marine and non-marine beds and was wondering how conformable they are - how continuous is the sequence of layers? I know about cyclothems and coal beds but what of the typical non-marine amphibian/reptile/mammal fossil bearing rocks where, eg, dinosaur fossils are found, what are these sequences like?

------------------
You are go for TLI


  
Tranquility Base
Inactive Member


Message 2 of 221 (9998)
05-20-2002 1:06 AM


No comments? BUMP.
Replies to this message:
 Message 3 by Joe Meert, posted 05-20-2002 1:14 AM Tranquility Base has not yet responded

  
Joe Meert
Member (Idle past 3843 days)
Posts: 913
From: Gainesville
Joined: 03-02-2002


Message 3 of 221 (9999)
05-20-2002 1:14 AM
Reply to: Message 2 by Tranquility Base
05-20-2002 1:06 AM


Let's try to narrow our topics a bit in the interest of economy. For example, I still want to know what sediments (in the conventional column) are pre, syn and post flood. I promise to answer your (BROAD) question. Simply put, there is no 'all encompassing answer".

Cheers

Joe Meert


This message is a reply to:
 Message 2 by Tranquility Base, posted 05-20-2002 1:06 AM Tranquility Base has not yet responded

    
Tranquility Base
Inactive Member


Message 4 of 221 (10435)
05-27-2002 10:57 PM


I'd like to resurrect this thread if possible. So Joe - we have the full spectrum of terrestial (land) strata do we - some neatly layered and some not? That makes sense I guess.

Certainly at Grand Canyon there are large non-marine formations that are comprised of neatly stacked layers. How is that explained in a mainstream context? If it's flood after flood there should be thousands of unconformaties (interfaces with gullies and erosion) as we travel down the local column in these beds disrupting the neat parallel stacking. Surely conformable non-marine sequences, such as those at Grand Canyon, argue for a single event for that bed as argued by flood geologists?

PS - Joe: I've given you my pre/syn/post-flood boundaries elsewhere as coinciding with TC and most ICR/AIG publicaitons although I'm prepared to admit I have no professional scientific opinion other than to say that I would link the flood deposits to the epeiric sea formations at the very least and this is typically Cambrian to Cretaceous worldwide.

[This message has been edited by Tranquility Base, 05-27-2002]


Replies to this message:
 Message 5 by Joe Meert, posted 05-28-2002 12:11 AM Tranquility Base has responded

  
Joe Meert
Member (Idle past 3843 days)
Posts: 913
From: Gainesville
Joined: 03-02-2002


Message 5 of 221 (10443)
05-28-2002 12:11 AM
Reply to: Message 4 by Tranquility Base
05-27-2002 10:57 PM


quote:
Certainly at Grand Canyon there are large non-marine formations that are comprised of neatly stacked layers. How is that explained in a mainstream context? If it's flood after flood there should be thousands of unconformaties (interfaces with gullies and erosion) as we travel down the local column in these beds disrupting the neat parallel stacking.

JM: I guess I am troubled by your use of 'flood after flood'. What exactly do you mean? There are many thick non-marine rock layers (the Navajo sandstone, Fish River Formation and many units within the Vindhyanchal basin come to mind). I think you need a field trip!

Cheers

Joe Meert


This message is a reply to:
 Message 4 by Tranquility Base, posted 05-27-2002 10:57 PM Tranquility Base has responded

Replies to this message:
 Message 6 by Tranquility Base, posted 05-28-2002 12:44 AM Joe Meert has not yet responded

    
Tranquility Base
Inactive Member


Message 6 of 221 (10445)
05-28-2002 12:44 AM
Reply to: Message 5 by Joe Meert
05-28-2002 12:11 AM


I would love to go on some field trips. Having said that, isn't it true to say that:

(i) There exist large non-marine beds with hundreds of feet of neat parallel stacked layering (eg that are visible in the Grand Canyon cutting as well as your examples).
(ii) If these were formed gradually on land (eg by either normal rain or big storms) the conformity would be disrupted and we would see hundreds and thousands of unconformities?

[This message has been edited by Tranquility Base, 05-27-2002]


This message is a reply to:
 Message 5 by Joe Meert, posted 05-28-2002 12:11 AM Joe Meert has not yet responded

Replies to this message:
 Message 7 by Minnemooseus, posted 05-28-2002 1:43 AM Tranquility Base has responded

  
Minnemooseus
Member
Posts: 3723
From: Duluth, Minnesota, U.S. (West end of Lake Superior)
Joined: 11-11-2001


Message 7 of 221 (10451)
05-28-2002 1:43 AM
Reply to: Message 6 by Tranquility Base
05-28-2002 12:44 AM


First of all, I thought I'd post some definitions from the site's geology glossary:

Unconformity - A discontinuity in the succession of rocks, containing a gap in the geologic record. A buried erosion surface. See also angular unconformity, nonconformity.

Angular unconformity - An unconformity in which the older strata dip at a different angle (generally steeper) than the younger strata.

Nonconformity - An unconformity in which stratified rocks rest on eroded granitic or metamorphic rocks.

Disconformity - An unconformity in which beds above and below are parallel.

Now let me repeat a portion of the above:
Unconformity - A discontinuity in the succession of rocks...

Sedimentary discontinuities come in a vast range of varities. They can be on a very small scale, such as the boundry between one thin bed and another thin bed.

Much more extreme discontinuities are such as angular unconformities. A very extreme example is the nonconformity found in the Minnesota River valley. There, gneisses with radiometric dates of somewhere about 4 billion years are overlain by Pliestocene glacial sediments.

So, there are minor unconformities, and there are major unconformities. I would think that only in very stable depositional environments (such as an eperic seafloor) would unconformities be truly rare. In the non-marine environment, small unconformities would be abundant. Think of all the truncated relationships in a crossbedded sandstone.

Not a real coherrant posting on my part, but I wanted to get these thoughts out before they escaped me.

Moose

------------------
BS degree, geology, '83
Professor, geology, Whatsamatta U
Old Earth evolution - Yes
Godly creation - Maybe


This message is a reply to:
 Message 6 by Tranquility Base, posted 05-28-2002 12:44 AM Tranquility Base has responded

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 Message 8 by Tranquility Base, posted 05-28-2002 2:55 AM Minnemooseus has not yet responded

    
Tranquility Base
Inactive Member


Message 8 of 221 (10453)
05-28-2002 2:55 AM
Reply to: Message 7 by Minnemooseus
05-28-2002 1:43 AM


Thanks - Moose - I'm aware of this but it's good to have it sitting in front of us. What I'm trying to point out is that in the non-marine beds of the Grand Canyon series there are very few 'genuine' unconformities - ie where there is erosion visible - gullies etc. I would actually normally expect gradually formed non-marine beds to be pretty messed up.

So what is the mainstream understanding of the nicely layered non-marnine formations like at Grand Canyon?

[This message has been edited by Tranquility Base, 05-28-2002]


This message is a reply to:
 Message 7 by Minnemooseus, posted 05-28-2002 1:43 AM Minnemooseus has not yet responded

Replies to this message:
 Message 9 by edge, posted 05-28-2002 11:32 AM Tranquility Base has not yet responded
 Message 10 by wehappyfew, posted 05-28-2002 11:04 PM Tranquility Base has responded

  
edge
Member
Posts: 4605
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 4.5


Message 9 of 221 (10474)
05-28-2002 11:32 AM
Reply to: Message 8 by Tranquility Base
05-28-2002 2:55 AM


quote:
Originally posted by Tranquility Base:
Thanks - Moose - I'm aware of this but it's good to have it sitting in front of us. What I'm trying to point out is that in the non-marine beds of the Grand Canyon series there are very few 'genuine' unconformities - ie where there is erosion visible - gullies etc. I would actually normally expect gradually formed non-marine beds to be pretty messed up.

So what is the mainstream understanding of the nicely layered non-marnine formations like at Grand Canyon.


Just a couple of quick comments. First, it is not at all uncommon (and seems logical) that many unconformities plane off the lower beds giving the appearance of evenness, though the deposits may have consisted of large sand dunes. Imagine a coastal plain sliced level by wave action of a receding or advancing sea.

Second, it can be said that all bedding planes or laminae represent brief unconformities. Many are so short that there is no erosion or folding, but others, for instance those which often define a set of cross-beds, do give evidence of some erosion and are often planar.

[This message has been edited by edge, 05-28-2002]

[This message has been edited by edge, 05-28-2002]


This message is a reply to:
 Message 8 by Tranquility Base, posted 05-28-2002 2:55 AM Tranquility Base has not yet responded

  
wehappyfew
Inactive Member


Message 10 of 221 (10524)
05-28-2002 11:04 PM
Reply to: Message 8 by Tranquility Base
05-28-2002 2:55 AM


quote:
Originally posted by Tranquility Base:
Thanks - Moose - I'm aware of this but it's good to have it sitting in front of us. What I'm trying to point out is that in the non-marine beds of the Grand Canyon series there are very few 'genuine' unconformities - ie where there is erosion visible - gullies etc. I would actually normally expect gradually formed non-marine beds to be pretty messed up.

So what is the mainstream understanding of the nicely layered non-marnine formations like at Grand Canyon]


Actually, I am having some difficulty finding Grand Canyon non-marine unconformities that DO NOT exhibit signs of extensive weathering and erosion...
From the web-site I referenced in the other thread (Triassic Strata of the Colorado Plateau), a brief description of just the Triassic strata of the Grand Canyon contains these references to erosion and weathering:

"...there are caverns in the Redwall Limestone which often contain remnant clasts of these previously existing, overlying sedimentary rocks, including clasts from the Chinle Formation..."

"...As noted previously, an erosion surface is present at the Kaibab-Moenkopi contact in northwestern Arizona, southeastern Nevada, and southwestern Utah, including channels 250ft deep and 700ft wide in Rock Canyon, and possible paleokarst depressions..."

"...Raindrop prints and salt casts are present on some bedding planes..."

"...The Chinle Formation consists of a conglomerate valley-fill sequence overlain by fluvial, floodplain, marsh, delta, and lacustrine deposits..."

"...The depositional environments include channels, overbank/crevasse splays, floodplains, and minor lacustrine facies, with increasing evidence of eolian and lacustrine deposition at the top of the section. Three unconformity-bound sequences have been observed in these deposits. The first two sequences consist of basal channel-fill conglomerates and sandstones that fine upwards into dominantly flood-plain mudstones and paleosols. The third sequence consists primarily of interbedded siltstones and fine sandstones, and demonstrates an increasing eolian trend..."

"...The basal Chinle member, the Shinarump Conglomerate, consists of conglomerate-filled channels up to 40 meters thick. In some areas the Shinarump Conglomerate contains clasts as large as a car. The conglomerate also contains gravelly fossiliferous clasts derived from the underlying Kaibab limestone..."

"...Many of these logs have been permineralized into agate or jasper. Most of the petrified logs seem to have been transported, but some in situ stumps have been reported..."

"...Camborygma burrows with diameters in centimeters and lengths from 30 cm to 200+ cm are known from the upper Chinle, and in the correlative Dockum Formation of northwest Texas and eastern New Mexico. These may include chimney structures at their tops, and a "surficial burrow morphology including scrape marks, scratch marks, mud-and lag-liners, knobby and hummocky surfaces, pleopod striae, and body impressions" (Hastiostis et al.. nd). Hastiostis (1990; 1991) and Hasiotis and Mitchell (1993) attribute these to crayfish, which produce burrows with virtually identical features..."

"...Archeoentomoichnos burrows are perhaps the most interesting. These consist of "multistory ramps, floors, and walls constructed in a cylindrical structure approximately 7 cm in diameter; associated with mm to cm diameter-sized corridors greater than 5 cm in length; walls, ramps, and floors, range in thickness from 2 mm to 5 mm. . . These nests represent the earliest known examples of social behavior in insects as well as the oldest evidence of termite activity. The ichnofossil evidence predates the body fossil evidence of termites by 135 million years (early Cretaceous). The nests are composed of calies (nest proper), galleries (runways between nests), and peripheral calies (storage chambers)..."

"...Paleosols of varying degrees of maturity are found throughout the Chinle:
Major types of paleosols present in the Chinle include Gleysols, Alfisols, Vertisols, Calcisols, and Aridisols, all of which also range in stages of maturity based on the amount of time in their formation (e.g., Mack et al., 1993)..."

Until you provide some references to back up your assertion that erosion is generally absent from the G. Canyon strata, I must conclude that your knowledge base is insufficient to support your opinions.


This message is a reply to:
 Message 8 by Tranquility Base, posted 05-28-2002 2:55 AM Tranquility Base has responded

Replies to this message:
 Message 11 by Tranquility Base, posted 05-29-2002 10:18 PM wehappyfew has not yet responded

  
Tranquility Base
Inactive Member


Message 11 of 221 (10603)
05-29-2002 10:18 PM
Reply to: Message 10 by wehappyfew
05-28-2002 11:04 PM


I'm not saying that non-neatly layered terrestial fromations don't exist. But for the neatly layered ones that do exist, such as Hermit Shale or Supai how did they from from a mainstream POV? And the Redwall is a marine formaiton isn't it? I'm aware that some of these formations are a mixture of marine and freshwater of course.

[This message has been edited by Tranquility Base, 05-29-2002]


This message is a reply to:
 Message 10 by wehappyfew, posted 05-28-2002 11:04 PM wehappyfew has not yet responded

Replies to this message:
 Message 12 by edge, posted 05-30-2002 1:07 AM Tranquility Base has responded

  
edge
Member
Posts: 4605
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 4.5


Message 12 of 221 (10612)
05-30-2002 1:07 AM
Reply to: Message 11 by Tranquility Base
05-29-2002 10:18 PM


quote:
Originally posted by Tranquility Base:
I'm not saying that non-neatly layered terrestial fromations don't exist. But for the neatly layered ones that do exist, such as Hermit Shale or Supai how did they from from a mainstream POV?

Not sure, but it seems to be part of a regressive sequence, with a gradual transition from marine(?) Redwall to eolian Coconino. See how this fits right in with the presence of an epeiric sea that is in regression? You seem to think that non-marine deposits are completely independent of the marine and have nothing to do with epeiric seas. It isn't so.


This message is a reply to:
 Message 11 by Tranquility Base, posted 05-29-2002 10:18 PM Tranquility Base has responded

Replies to this message:
 Message 13 by Tranquility Base, posted 05-30-2002 1:48 AM edge has responded

  
Tranquility Base
Inactive Member


Message 13 of 221 (10618)
05-30-2002 1:48 AM
Reply to: Message 12 by edge
05-30-2002 1:07 AM


The marine merging into non-marine fits our scenario too.

But here's the important point. In your vast layered non-marine Grand Canyon deposits why do we get land plant fossils strewn throughout these hundreds of thousands of square miles of strata? Why not just at the lake/sea edges? There is nowhere on earth where vast quantities of land plants get dragged hundreds of miles out to sea? I think you'll find that layered non-marine beds will not have very good mainstream explanations Edge - but surprise me. We think a vast flood explains this data very nicely - not to mention cyclothems and coal.


This message is a reply to:
 Message 12 by edge, posted 05-30-2002 1:07 AM edge has responded

Replies to this message:
 Message 14 by wehappyfew, posted 05-30-2002 3:35 PM Tranquility Base has responded
 Message 16 by edge, posted 05-30-2002 10:31 PM Tranquility Base has responded

  
wehappyfew
Inactive Member


Message 14 of 221 (10658)
05-30-2002 3:35 PM
Reply to: Message 13 by Tranquility Base
05-30-2002 1:48 AM


quote:
Originally posted by Tranquility Base:
But here's the important point. In your vast layered non-marine Grand Canyon deposits why do we get land plant fossils strewn throughout these hundreds of thousands of square miles of strata? Why not just at the lake/sea edges? There is nowhere on earth where vast quantities of land plants get dragged hundreds of miles out to sea? I think you'll find that layered non-marine beds will not have very good mainstream explanations Edge - but surprise me. We think a vast flood explains this data very nicely - not to mention cyclothems and coal.

I wish you would slow dowm, TB. On this thread and the other one, you have sprinted from one mistaken assumption to another with little pause to reflect on the vain attempts at correcting the serious problems in your geological understanding.

The statement above is a good example.

First, you provide no data or examples to illustrate your point. Your assertion that land plants are "strewn throughout" large areas is so vague that it cannot be asessed seriously. You are forcing us to guess what you might be talking about.

Second, you are failing to think in the dimension of time as well as space. In geologic time, a delta that progrades and retrogrades across a continental shelf or epeiric sea will leave a broad expanse of fluvial, delta, tidal and shallow marine sediments over the entire area it covers (in 4 dimensions). Modern analogs of this are easy to find... the Mississippi Delta has many abandoned fluvial features like oxbow lakes, levees, birdsfoot deltas, etc that have exact one-to-one correspondence with ancient sedimentary structures. These modern features are found spread across the entire Mississippi floodplain and delta - hundreds of miles wide and deep.

In other words, the features you are referring to ARE found "just at the lake/sea edges", but the edge of the sea, lake or river has moved back and forth.

quote:
I think you'll find that layered non-marine beds will not have very good mainstream explanations

Examples and data... without it, you are blowing smoke. I have already provided a long list of unconformities and erosional features you claimed at first did not exist... I think you will find this is another case of reality failing to conform to your mythology.

To review, I will list your unfounded and incorrect impressions revealed in this thread. Your ability to respond with data and evidence will be a strong indication of the seriousness of your stated desire to learn about "mainstream" geology. Quotes from the secondary literature count for little, BTW.

1. Cyclothems explained by massive floods - how can alternating layers of very finegrained limestone and clay be deposited at all in a Flood?

2. Ditto for coal - examination of almost any actual coal bed will reveal plenty of evidence contradicting this Creationist myth.

3. The Hermit Shale cannot be considered "neatly layered" if it lies unconformably on the underlying Supai Group. And it does.

3a. The Supai and Hermit both contain abundant cross-bedding, ripple marks, conglomerates, and other small-scale unconformities. So at some levels, the "neatly layered" look completely disappears.

4. The Redwall is, indeed, marine. But you fail to consider the consequences of the evidence I cited. The Redwall contains paleo-karst and other erosional features that entirely preclude a Noah's Flood explaination. Clasts of Redwall limestone are present as basal conglomerates in the overlying formations. Clasts of overlying formations are present as infillings in sinkholes and caverns within the Redwall Formation. Some of these overlying formations have been entirely removed in localized areas by erosion, yet their clasts are preserved within the cavities of the Redwall. The myth of soft sediment erosion of the Grand Canyon is completely impossible in light of this evidence.

5. There exists large non-marine beds with hundreds of feet of neat, stacked layers (as you posited in post 6), but the layers are NOT PARALLEL!!! This is plainly evident by the fact that all Grand Canyon strata thicken to the west, and many are shallow marine, tidal and deltaic. The importance of this point cannot be overstated. It, alone, pre-empts any possibility that these strata were laid down in a short period of time.

6. You are mistaken if you think we do not see hundreds and thousands of unconformities in the GC. There are gullies and other erosional surfaces found thoughout the GC. I listed quite a few found in one small section of the Grand Canyon strata, yet this seemed to make little impression on you.

Tonight I will do the same for the other thread.


This message is a reply to:
 Message 13 by Tranquility Base, posted 05-30-2002 1:48 AM Tranquility Base has responded

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 Message 15 by Tranquility Base, posted 05-30-2002 9:41 PM wehappyfew has responded

  
Tranquility Base
Inactive Member


Message 15 of 221 (10678)
05-30-2002 9:41 PM
Reply to: Message 14 by wehappyfew
05-30-2002 3:35 PM


Wehappyfew, I have posted references along with some of my claims. Other claims I have made becuase they are general impressions I have gained and I agree I ultimately need refs but I also hoped that there would be people here who knew the answers. But I am still at it, this is a work in progress.

I'll give you an example. I made the simple statement in the other thread that 'I knew' that much of the geological column was laid down by epeiric seas. Do you think anyone here came and said - we agree, now continue. No, I had to go find the evidence. That's fine, I learnt a lot doing it.

OK, this case I am claiming, is based on general reading and no specific reference, that there are vast terrestial beds with terristial plant and animal fossils strewn horizontally throughout the strata. Why don't we together find out? I'm searching, but some of you are geologists and either already know the answer or can find out easier than I can. I brought it up so I should prove it but I reserve the right to comment on a general impression in the case that someone here does know the answer of the top of their head! That's all that I'm doing. I am not trying to incite anything. I'm telling you my impression of the data, the mainstream sceanrio, the creationist scenario and my own synthesis of it.

What I have based the claim on is books I've read about Grand Canyon strata. And these state that strata are dominated by confiers, ferns etc etc. If you think they are only at 'edges' then you equally need to show that with refs. I perfectly understand how one expects to get a 'diagonally' travelling sea edge during transgression/regression. But when we hear that a partilcular stratum is 'dominated' by conifers and ferns then I will usually assume that it is not just along a lake boundary. We both need refs to show this, in particular for Grand Canyon non-marine strata. I don't deny there are genuine 'lake edge' phenomena but, from my reading, that is not the case in the vast layers of the fresh water depoists that overlap with the epeiric seas (in terms of plant fossil locations).

I don't believe I have made mistake after mistake here. I have honestly offered you my current understanding and you have all contributed to my educaiton in geolgoy, yes, but, IMO, it hasn't changed my basic thesis.

We explain coal as occurring via the burial of state sized floating mats of vegetation uprooted catastrpohically. The next surge could have deposited sandstone and limestone.

The Hermit Shale is in itself neatly layered, as is the Supai. There is a very flat unconformity separating the two formations but there is no evidence for 1000s of non-marine events within these formaitons. I can only assume that you guys think that some how these were fresh water coastal lakes or river deltas and may not have considered why there are land plant fossils horizontally throughout strata.

Unless I'm mistaken, I've never seen cross bedding and ripple marks described as unconformities. These type of phenomena occur pwithin stratum. Unconformities typically generate relief traversing multiple strata.

Can you explain your Redwall issue again. I have no problem with there being an unconfromity at the top of this sequence. Why couldn't conglomerates have been transported in?

I think you overstate the significance of the layers narrowing. There is nothing in our scenario which states that layers don't gradually disappear horizontally! We think big but no one expects layers to be universal.

Your hunreds and thousands of unconformities? Any layman looking at the Grand Canyon strata knows that there are almost no interfaces which look like the current topgraphy of the earth with the Grand Canyon strata. We are arguing extents here. I have not even mentioned the trivial relief that occurs at the boundary of the Carboniferous Redwall Limestone and the supposedly much older Cambrian Muav Limestone. Trivial relief and 200 million years of missing time!

I agree, let's look for refs but I think you'll find that I am right on the vast non-marine layers, at least in Grand Canyon. There is good support for the floating mat model of coal formation and the vast non-marine, non-coal bearing layers are essentially the same phenomenon - rapid freshwater flooding carrying plant material across vast temporarily flooded regions.

[This message has been edited by Tranquility Base, 05-30-2002]


This message is a reply to:
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Replies to this message:
 Message 20 by wehappyfew, posted 05-31-2002 2:31 AM Tranquility Base has responded

  
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