Just Sayin’: Not all bays were lakes

Chris Moore, Andy Ivester and other skeptics of sudden bay formation recently published a beautiful poster detailing their findings and discussing their conclusions. I was impressed and disappointed. Impressed to see thoughtful research into the bay phenomena, disappointed that it ignored our previous published work determining that at least one (and presumably many more) Carolina bays were never lakes.

Here is their poster:

Download (PDF, 2.89MB)

And below is an excerpt from our abstract concerning the nature of the sands in the eponymous “Howard Bay,” and below that our 2007 Acapulco AGU Carolina Bay poster.

Point is, to refute our conclusion that bays formed suddenly by invoking long-lived “lakes,” Moore and Ivestor need to disprove that, 1) Howard Bay is indeed a Carolina bay formed like all others; and/or 2) It was never a lake.

If our poster helped reignite the terrestrial versus or ET causation debate, then the poster’s conclusions should be addressed directly. It seems the best way would be for Moore, Ivestor and team to core Howard Bay themselves and prove a lake once lived there.

Further analyses of samples in complete core sequences reveal that, unlike typical, peat-rich Carolina Bays, Howard Bay essentially lacks peat, diatoms, pollen, or other organic materials, suggesting that this Bay never stored water for any sustained length of time. Furthermore, several trenches confirm that the deepest part of the Bay is filled with >6 m of cross-bedded eolian sand with no evidence of lacustrine sedimentation. This evidence calls into question prevailing hypotheses (a) that all Bays were lakes and ponds in the past and that their shapes were formed by wave action, or (b) that groundwater movement led to subsidence that formed the Bay….

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  • Steve Garcia

    George –

    Yes, there are some comments to be made about Moore’s poster. For anyone to follow this, they are going to have to download the .pdf and zoom and pan around. I think if they do they will see how bad this poster actually is. As Moore did 3 or 4 years ago, he starts out with his conclusion – “everything there is aeolian” – and it dictates every interpretation he makes.

    These are the things that I find questionable in their conclusions:

    GPR File 001

    1. They label the substrata as “mud” which seems quite unspecific and, to be honest, rather unscientific to not name it more specifically.

    2. In the transect GPR File 001 the mud subsurface is not flat and conforms very consistently with the top surface about 3 meters down, but in the Geoprobe Core Transit they sketch in the mud as being much flatter. With the vertical scale shown the mud surface comes out to be essentially flat. This even though the two transects are parallel and very close to each other.

    – – – – The NON-flatness of the GPR mud surface would seem to suggest that the landform UNDER the bay rim(s) was there and was deformed before the bay sand was lain on top of it – and that the sand is merely following the land form underneath. In essence, the sand is “draped” (there really is no better word for it) over the mud landform – exactly as I’d pointed out ~3 years ago.

    – – – – The sand being draped over, this argues that the wind is NOT forming the bay rim but that the underlying mud/clay is itself deformed by some unspecified process before the sand was laid down.

    – – – – Either that or the entire layer-cake was deformed together.

    – – – – Since mud/clay is sediment laid down by deposition, it is most normally laid down FLAT or following the counters of the previous sediment layers. No explanation is given for why the mud is not flat. As far as I’ve ever seen (which admittedly is spotty) when there are subsurface layers shown in GPR that undulate like this it is assigned to folding of the layers geologically – meaning forces within the ground. This, of course, would be hard to explain in an elliptical surface morphology – how do you fold the surface all around an ellipse?

    3. The Core Logs & OSL Dating panel shows transect 003

    – – – – This transect is more or less perpendicular to the other two transects, meaning that it is more or less tangent to the curve of the rim. Thus, whether by accident or what, the mud surface is labeled “Scoured Surface,” even though it is (merely) sketched in as being FAR different from the actual surface morphology That is exactly what I would expect from sand deposition from above, as it splayed out from the impact – the basal surface should show evidence of scouring (and the scouring should be more or less radial – that should be something to look for).

    – – – – If one can trust the OSL dates***, they seem to imply a sand deposition at or about 40kya, not the 780kya date. I myself am distrustful of OSL dates, because I don’t know the protocols to ensure that the sample was not tainted with light in some way during collection and before testing. From what I read a good while ago, I recall that ANY exposure to light – even a second or two – starts the OSL clock going again.

    – – – – If you zoom in and look at the 4 cores, the sand at all depths IS sand and is quite consistently either “medium” or “fine” with only a few variances from that.

    – – – – – – If lain down as sediment, would it be so consistent?

    – – – – From Figure 2 in LIDAR Imagery and also from the GPR panel, too, it is clear that the researchers cherry-picked the core locations as being on the very top of the “rims” (“remnant rims”?). IMHO any solid research would also show cores in what they call “inter-shoreline swales,” to show that the core configurations are or are not consistent with the rim peak cores.

    4. Once again, IMHO Moore et al cherry picked the location of transects to show the results they wanted to show.

    – – – – They do not show what is going on the supposed “upwind” side of the bay rim, only the side (“corner”) downwind, where they can argue “See? The wind did it!” (THIS definitely goes in the category of cherry picking.) If I recall, they did this before, 3 or 4 years ago.)

    – – – – Even though they looked at the SE end, they chose the leeward side of the curve.

    – – – – Until some lacustrine-aeolian persons do research also on the NW or SW side of bays I can not accept that they are doing more than cherry picking. The reason for this skepticism is that no one can explain why the elliptical shape is on THAT side of the bays, also. Wind can ONLY do contouring DOWNWIND. Downwind we often see parabolic sand shapes (but not really any ellipses; curves, yes, but all curves are not ellipses). Upwind no one has ever seen a reverse parabolic sand shape. (Unless I am wrong about that, and I don’t think so.) It cannot pick up material from the bottom of the bays and PULL it back around to the windward rim. Thus, until they explain THAT 180° curve of the bays, we can put their work down to looking through rose-coloured glasses – seeing only what they want to see, and making sure that they only look where they think the geomorphology will give them the answers they seek.

    5. LIDAR Imagery

    – – – – In Figure 2, they label one of the more “faded” underneath features as “Remnant bay basin.” I would consider it possibly a separate bay that was laid down before the pristine one currently named Herndon Bay. It certainly would not be the only overlapped Carolina bay situation.

    – – – – The other “bay rims” – which is what Moore et al is ACTUALLY studying in this poster – CAN be put down to later aeolian reworking, except for one thing: The clay underneath is what everything above conforms to, and THAT they call “scoured”. How do they explain the geomorphology of the mud/clay bottom? That the wind created THAT, too?

    6. Comparison with GISP2

    – – – – This 3-core overlaying onto the ice cores reminds me of (the UNpublished, UN-peer-reviewed) Kaczorowski 1977 study, because they took only three points (from FOUR cores), and one is tempted to assert that when they got the result they were hoping for, they stopped there and did not try to replicate it. They have a 3-point curve that has the most recent date closest to the bay center, and that is good enough for them.

    – – – – This makes it actually suspicious that they claim to not have taken an OSL sample at Core 4 – in spite of having taken OSL samples at the other three. Why not? Or did they and perhaps the OSL sample at Core 4 did not fit their expectations? WHY would they not show their OSL dating for Core 4?

    7. The bay migration model

    – – – – Having written this all as I step through the panels, I almost spewed when this one actually refers to being based on Kaczorowski 1977.

    – – – – This plan view as drawn makes no sense. The authors assert “erosion” on the windward portion of the bay rim curve – even though the rim is still a RIM and is NOT eroded down, but sticks UP. Any erosion on the windward side of the bay ellipse would erode the top down, making a more flattened or non-existent rim.

    – – – – The authors INVENT – without giving its basis – the “subaqueous circulation cell” motions, perhaps out of thin air.

    – – – – Also in the plan drawing, they FUDGE on the location of the “remnant bay rim” in two ways:

    – – – – – – The location of that remnant bay rim is shown more coaxial with the current bay than it is in the LIDAR

    – – – – – – They cheat on the A-A’ axis for the main bay by drawing it through the SE tip of the “remnant bay rim”, further hinting at the two bay alignments being in line. (It is clearly NOT symmetrical with Herndon Bay itself.)

    – – – – – – What I see is two separate bays, one (the later) overlying the other. They see them as the same bay having migrated. I don’t think they have made a strong enough case.

    – – – – They also draw the latter symmetrical upon the axis of the SW winds, but NOT symmetrical upon the axis of the NW winds.

    – – – – In the cross-section drawing they clearly misrepresent the GPR sand layer. They show them as being anything BUT paralleling the mud/clay below. This one I actually would call chicanery and mendacious. As drawn, the “water-lain (shoreface) sediments” are CLEARLY far different from the GPR transects and the Geoprobe Cores. Such “sediments” do not even EXIST in the GPR or the Geoprobe data, as presented – those two show underground features as faithfully following both the mud/clay basal surface and the rim surface. (Though their “faked in” mud surface in the lower figure doesn’t show what I am saying; in any event, all the data show the underground discontinuities parallel to the bay rim surface.) Their drawn-in “water-lain sediments” simply don’t exist as drawn.

    DISCUSSION

    – – – – It opens with “Evidence from Herndon Bay suggests periods of bay migration, including scouring of the underlying mud facies.” They give NO mechanism whatsoever for this supposed “migratory scour.” Once covered by sand – which will embed into the mud, if for no other reason than the weight of what is over the sand, the basal mud “facies” surface will be immune to scour. While I would LIKE there to be mud scour (it would support a sand deposit as ejecta model quite nicely), at this moment I am not sure the “scour” even exists.

    – – – – “Periods of stability are punctuated by periods of high-energy shoreline processes leading to bay basin migration and the development of a regressive sequence of sand rims.” Though asserted as fact, this is supposition – a conclusion without basis, simply what they WANT to be true. They claim without sufficient evidence and without having done one thing to show that they have challenged their premise, to show that the premise is robust. The latter is an important step in the scientific method. All of what they argue is one-sided – but I see holes throughout the entire presentation (which is what my babbling here is all about***).

    – – – – They assert a linear migration, based on only 3 data points. Very VERY unscientific – similar to Kaczorowski 1977.

    – – – – They assert a migration to the NW, but other than LIDAR imagery that shows two main bays, one under the other, there is no migration. Their 3 data points for OSL are pathetically inadequate for making the assertions they make. Had they taken the samples at slightly different depths, they would possibly have gotten a different time curve – especially if their premise is correct.

    – – – – – – What would have been REALLY instructive is if they had taken OSL dates at different depths in the same cores. (If the different ones from the same core came out the SAME, then THAT would support YOUR idea. You should do that, if possible! And if the sand WAS all deposited at the same time, that is exactly what should be found – all OSL samples in the same core with the same dates, top to bottom.)

    – – – – – – The OTHER “rims” can just as easily be seen as wind-blown dunes, blown off the SE rim as part of reworking of the bay rim. These being wind-blown in no way is conclusive that the original rim (main rim) of Herndon Bay is itself aeolian.

    – – – – Basing ANYTHING on the pathetic so-called and un-replicated paper of Kaczorowski 1977 is really bad science. These people cannot see the inadequacies of Kaczorowski 1977. Using it as a foundation without replicating it is really, REALLY bad science. (Richard Feynman rips into this kind of science very thoroughly in his longer YouTube about the Scientific Method, as well as his 2004 CalTech Graduation speech.) I understand that Moore tried to replicate Kaczorowski’s 1977 experiment, and that the attempt failed miserably. That is not surprising, since Kaczorowski only ran about 4 complete cycles and when he saw something approaching an elipse, he stopped. And he never attempted to replicate his own work, as far as is known.

    As far as my eyes and brain can see, all of what they are describing is reworking of the bay rim. Nothing in this poster discusses the causes of the original formation – WHY would the mud underneath be the same contour as the bay rim? Nobody asks that.

    ***I am not doubting OSL itself, but it is critical to choose the proper geomorphic location and then to also choose the proper depth. I also question that in a possibly disturbed location – perhaps folded over – that the dating can be assumed to be a simple matter.