tisdag 15 april 2014

Truth matters? Apparently not about sediment varves for young-earth creationists

Dave Hawkins at the blog "Truth Matters" is evidently a young-earth creationist who, like most other young-earth creationists, has to spend inordinate amounts of time and energy denying reality. The world is full of deluded people and normally it is not worth our time to give them any attention. However, it so happens that a blog post of Dave's about Lake Suigetsu and sediment varve (see also here) chronologies came up in a discussion (in Swedish). I have run across Dave's post before, and at the time just glanced through it to identify the most glaring falsehoods and mistakes. Normally there would be no need to spend time debunking this; Dave is honest (or suicidal) enough to provide links within his blog post to discussion forums where people explain to him exactly why he is dead wrong in his conjectures. In the comments there is also a link to an efficient and concise debunking of his post.  Alas, this does not seem to register with Dave; judging from the irritation displayed by his opponents, it is not the first time they try to explain these things to him.

However, the creationist Erik Scherman probably failed to perform due diligence in applying critical thinking when reading Dave's post and citing it in the discussion. For the sake of that discussion I need to shoulder the distasteful burden to demonstrate that truth indeed matters very little, when it comes to something that goes against the preconceived notions of Dave and other young-earth creationists. Ah well; here we go:

Dave: " They say that Lake Suigetsu has a continuous record of varves (fine laminations deposited annually) in the sediment below the lake for the last 100,000 years or so. [...]

But does it really? Or is this just one more false claim put forth by anti-creationists? [...]

We cannot say for sure yet, but it’s looking like yet another false claim. I have now been investigating Lake Suigetsu off and on since June 2007 and I have discovered some very fascinating stuff. For instance …"

[wait for it...]


Dave's first "argument" is thus not an attempt to deal specifically with the matter at hand, but a rather blunt rhetorical device to soften us up by throwing  uncertainty about the whole concept ov varves into the discussion.

Dave provides a quote from geologist R.M. Quigley, cited in a (now disappeared?) Answers in Genesis article, that bears every sign of being a quote mine to cast unwarranted doubt on the varve phenomenon. I hope it is obvious to the general reader that this has no bearing on the case at hand. When scientists are aware of a potential source of error and apply more stringent criteria as a result, this is not a sign that the whole phenomenon is questionable.

Moreover, in the forum discussion it is shown that the Quigley quote is indeed a quote mine; Quigley's text is partly an appeal for more stringent terminology to avoid confusion, and partly a discussion about diagnostic criteria to distinguish true varves from non-annual events. Unfortunately, this exchange seems to have very little impact on Dave's thinking (see also here - Dave is not a first-time offender when posting his blog post, but has been engaged in the same discussion for weeks). Instead, Dave (inexplicably) comes away with the impression that there is a legitimate case to be made that true annual varves are somehow in doubt.

Fortified with these general conjectures, Dave now launches into a specific example that is supposed to further undermine the case for sediment varves (brace yourselves!):


Oh my! Somewhere, someone misinterpreted sediments as varves! I guess that means that we have to scrap the whole idea..? Does Dave argue that  the whole evidentiary material for varves is undermined by a single case of someone sloppily mis-assigning a banded sediment formation? Hard to tell, because Dave does not attempt to put this single case in a general context. He just throws it out there without any further comments, in a "just sayin..., nudge, nudge"-kind of way. However, in a forum discussion right around the time of Dave's blog post it is obvious that this is more or less Dave's point. In the forum, it is explained to Dave multiple times why Third Sister Lake sediments are different in several fundamental ways from true annual varves, including those found in Lake Suigetsu, but I see no mention of this in the blog post.

Third sister lake exhibits banded sediments that in the 1930s and 1960s apparently were mistakenly assumed to represent varves, but a thorough sedimentological analysis of these banding patterns by Hammer and Stoermer (1997) demonstrated that these bands did not correspond to annual events.

Ironically, rather than undermining the general case for varves, the analysis is a text book example on how diagnostic criteria in the form of sedimentology and algal blooms can be applied to distinguish true varves from other banded sediment patterns. There could hardly be greater differences between the sediment bands found in Third sister lake and genuine biogenic/glacial varves represented by examples from Lake Heinälampi (Sandman et al. 1990; Quoted in Hammer and Stoermer 1997), Lake Suigetsu, (Nakagawa et al. 2012) and Passumpsic Valley (Figure 1).

Figure 1. Examples of one non-varved (=non-annual)  banded sediment pattern from Third sister lake (Hammer and Stoermer 1997), contrasted against three genuinely varved sediment cores from Lake Heinälampi (Sandman et al. 1990), Lake Suigetsu (Nakagawa et al. 2012 with inlaid varve closeup from here) and Passumpsic Valley. Both Heinälampi and Suigetsu cores are confirmed to be varved by means of diatom bloom events, sediment chemistry, and isotope signatures. Two consecutive drill events in Heinälampi 4 years apart demonstrate that 4 layers of surface sediments have been added during this time (see inlaid picture).

These examples demonstrate that true varves can be reliably diagnosed, based on criteria that correspond to known processes: annual diatom blooms (see also here) and other sedimentary and chemical processes that are well understood. In case of Heinälampi, the varve chronology is established all the way from the sediment surface and down, through freeze sampling of the upper sediment layers.

When possible, every effort is also made to anchor the chronology against other known events and validate the reliability of the varve count against independent data. At Lake Kälksjön, Stanton et al. 2010 validated a 9000 year varve count from the sediment surface (via freeze sampling) using liming events during the first decade, Cs137 (nuclear tests and Chernobyl) going back 50 years, Pb isotopes from lead smelting going back 2000 years, and C14 dating going back to approximately 10 000 years.

Figure 2. Varve counting and validation at Lake Kälksjön from Stanton et al. 2010. Upper left: Images of varves, with two liming events marking reference years. Upper right: description of the full sediment core, with varve chronology and corresponding C14 radiocarbon "dates".  Lower left: matching varve counts against Cs137 peaks from nuclear testing and the Chernobyl nuclear disaster. Lower right: matching varve counts against Pb signatures from Greco-Roman and medieval  lead smelting at around AD 1 and AD 1000, respectively, noting 250 missing varves.

Dave's case is thus nothing more than a rather transparent attempt to sow collective doubt about varve chronologies by presenting a very biased representation based on a single example, while ignoring the many good examples of validated varve chronologies that are out there.

[Now we move on to the main topics in Dave's post: Lake Suigetsu itself]


Now, this is a gigantic red herring. Whether or not varves are forming in Lake Suigetsu today , and how close to the surface they can be distinguished in sediment cores, has no relevance whatsoever for the question whether the tens of thousands of laminations found in large sections of the sediment cores actually represent true, annual varves. Which they do, according to all relevant criteria (see everywhere in this post). Dave is trying to direct attention away from the real problem (problem for YEC, that is), which consists of well-documented evidence of a long history of annual deposition, by focusing on unrelated issues. Varving is a delicate process, dependent on annual cyclic processes that leave sedimentary traces that are not overshadowed by noise from other events, and that sediment surfaces remain sufficiently undisturbed for these traces to be buried in situ by subsequent sedimentary deposition. At any time in the history of a lake, these conditions may or may not apply. It would not be surprising if conditions in Lake Suigetsu have changed sufficiently in the last few hundred years that varves would no longer be forming, even if they have done so for long periods in the past.

That said, it would still be interesting from a general point of view to understand if varved sediments are still forming in Lake Suigetsu today. Besides, Dave is thoroughly mis-representing the data to cast doubt on the varves, as usual, and we can't have that, can we?

In fact, there is nothing in the references presented by Dave that can tell us with any confidence what the present situation is with regard to the forming of varves, and I have not found anything explicitly stated in other references either. Basing one's conclusions on the available material would amount to nothing more than idle speculation - or in Dave's case frivolous, biased assertions to push an agenda.

The latest composite core SG06 is described here as laminated in the top ca 46 m below the surface. In Staff et al. 2011 the upper 15 m (corresponding to ca 12 000 years) are described as "largely non-varved". In Nakagawa 2012 the description is more nuanced. Figure 7 shows clearly laminated sediments from the beginning of the displayed core, which is shown from ca 20 cm depth. Figure 10 shows a continuous "Lamination Visibility Index" along the whole core, indicating that the visibility of the varves in the uppermost section fluctuates above and below the values where individual varves can be distinguished. Bronk Ramsey et al (2012) present a full radiocarbon record with varve counts limited to between 11.2 and 52.8 kYR before present.

Based on several other cores from the 1990's, Kitagawa et al. 1995 and Kitagawa and van der Plicht 1998 perform varve counts including the first 10-15 meters, except for the uppermost ca 20-30 cm, which are described as non-varved in the 1995 publication. In another sediment core, Kato et al. 2004 describe laminated sediment from 12 cm depth.

Based on the available material, we can conclude that the processes giving laminated, varved sediments have been continuously active for most of the last 50-100 000 years at least up until a few hundred years ago. The quality of the resulting laminar varves apparently varies depending on both sediment depth and on the individual core sample. Regarding the uppermost decimeters of sediments, it is never stated explicitly whether these are truly non-varved, or whether this is an effect of the sediment surface being disturbed by the coring procedure. I have no idea how much surface disturbance is generally caused in this process, but in both of my examples where surface sediments are explicitly included (Sandman et al. 1990; Stanton et al. 2010), the authors used freeze-coring where the sediment surface is frozen in situ before/during coring to preserve its integrity. See also similar coring issues below.

Dave, however, provides unfounded speculations about if and when the varving process may have stopped, and immediately tries to use this as an excuse to question the significance of the laminations in the whole sedimentary column:

"Some people have claimed that the varves stopped forming in 1664 when the canal was built because of the influx of saltwater to a formerly freshwater lake. But if this is true, why does Kato assert that varves were still forming up until 1729? The answer, in my opinion, is that the ‘varves’ in Lake Suigetsu are not all true varves, that is annual laminations."

I have no idea who "some people" are, but I have found no information showing that these constructions would be tied to any immediate interruption of the varving process. Fukusawa et al. 2002 (pdf here) describe changes to the ecology of Lake Suigetsu in the last 500 years. These and other studies describe two features that are visible in Suigetsu sediment cores close to the surface and have been used to correlate different cores and as starting points for varve counts: A turbidite mud layer that has been tied to a 1662 earthquake, and a volcanic ash (tephra) layer from 1779. The earthquake caused uplifts in a riverbed, changing local hydrological conditions. In response a canal was constructed in 1664, which allowed influx of seawater into the lake, which gradually shifted from freshwater to brackish conditions. This shift is described in Fukusawa et al. 2002 and Kato et al. 2004, with regards to water and sediment chemistry and algal composition. Influx of salty seawater deposited at the bottom of the lake seems to have caused a more stratified water column, but there is no indication that this caused varving to cease. On the contrary; Kato et al. 2004 describe continuous yearly varves during the whole period, with a chronology calibrated against the 1662 earthquake and the 1779 eruption indicating only an error of five missing years during this time, placing the tephra layer at 1774.

In summary; there is no indication that there is anything wrong with Kato's assessment of varves, nor with the sedimentary column as a whole. In fact, I have found nothing except Dave's unfounded claims suggesting that varves are not forming in Lake Suigetsu today. Perhaps they do; perhaps they don't. But it is never clearly demonstrated nor explicitly stated in any publication I have found. Anybody who is truly interested in this question should write to the many sedimentologists working at Suigetsu and ask for information.


[and Dave knows this how...?]

Here Dave bluntly asserts that Suigetsu laminations are more likely to be caused by turbidity currents than still water deposition, based on the following image (see below) that can be found on Glenn Morton's Suigetsu page (backup of original).

This is an example of claiming too much from too little information. There is no ground for this assertion based on a low-resolution image from about 20 cm2 of sediment core. Especially not in the context of auxilliary information that is provided together with the image that the light bands represent diatom blooms. But Dave needs this to be something other than varves, so then it of course has to be turbidity currents. Or something else. Just not varves.

It is also an example of a common feature typical for proponents of creationism and other pseudoscience: selectively focusing on evidence that (they delude themselves) supports their view. There was no reason to focus selectively on this image as representative of Suigetsu laminations, as there was more relevant information available already when Dave posted this in April 2008, including Kawakami et al. 1996, quoted in his own post (!), which describes the composition of varves in detail , and distinguishes varves from other features including turbidites and tephra layers. Dave should also have checked out Tanimura et al. 2006, containing a detailed analysis of light and dark laminae.

If Dave is bothered by the appearance of the laminations presented by Morton, all his objections should now have been laid to rest by the excellent depictions of laminations in Nakagawa et al. 2012 (shown  in my Figure 1. See also here.).

Dave never acknowledges the diatom evidence presented in the forums. What he does is present the following image from Kato et al. 2004, and asking his opponents to explain why it does not show cyclic annual variations in diatom concentrations:

The answer is, of course, that the figure is not designed to show this kind of variation. The data are presented to show variation over depths of several centimetres, appropriate to demonstrate changes over decades to hundreds of years. Annual millimetre variations are simply not visible on this scale. Surprisingly, It seems like Dave's opponents (for once) didn't catch this, or didn't bother to discuss it, but we can now offer a retrospective correction.


[...] Kato claims that the 1662 earthquake layer is at ~102cm below the top of her core while Kitagawa [1998?see rather Kitagawa et al. 1995 and Kawakami et al. 1996] puts his 1662 earthquake layer at ~29cm, roughly a 70 cm difference. Remember, we’re talking about two cores taken from the same lake fairly close to one another. Does this much variation over such a small area speak of slow, steady, annual deposition? To me, it does not. To me it argues strongly for episodic deposition…"

Ahh, here we go again, don't we? Episodic deposition is the pre-determined conclusion that Dave wants to get to, while the "evidence" he presents before is just a quasi-scientific filler. Any real or imaginary concern with sediment cores that Dave brings up always seems to point in one direction.

Again: whatever problems there may be with sediment depth above the layers in question, have no relevance for the strong correlation between different cores displayed in the varved sediments below these event layers. It is quite possible that sediments today are deposited in a much different way than before (with or without varves). Fukusawa et al. 2002 describe increased primary productivity in the lake today compared to hundreds of years ago, and several different tunnel and canal constructions that may have altered sediment flows. This is all irrelevant for the question of earlier varves.

And: Depending on how the two cores were obtained, there may be substantial differences in where their respective surfaces were positioned relative to the true sediment surface. There is a discussion here between Dave and his opponents about how corers work, and the variation regarding how far down in the sediment the corers may plunge before the coring process begins. Personally, I have no idea whether 70 cm is a significant difference in this context - but neither has Dave. He is only working from his intuitions that this seems like a big difference, but he has not bothered to access background data about how much variation can be expected between individual cores in relation to the sediment surface.


[..yes, what about it?...]

”So my question is, `Did Van Der Plicht’s AMS lab (who did Kitagawa’s tests) reject several small leaf bits as they were testing each leaf until they hit on one that roughly matched the ‘varve age’ that they were given beforehand?´ I see no reason why they would not have, given the knowledge we have about radiometric dating practices.”

Oh, it's the old canard about the scientific conspiracy/paradigm/bias/whatever that causes mainstream scientists to fudge their data to conform to the straitjacket of scientific dogma.

Well, without personal familiarity with either Dave or the C14 lab in question, we can nevertheless state with confidence that:
1) Dave has no real knowledge about radiometric dating practices. They are nothing like what you hear from creationist misinformers.
2) Dave is utterly deluded if he truly imagines that the reported gradual changes of many orders of magnitude of C14-amounts between the top and bottom of several independent sediment cores can be accomplished by selective reporting of data points. 
3) No, you silly nitwit - they would not have done that in the first place, because it would amount to scientific fraud, which is not part of good scientific practice.

See other responses to creationist Dave's assertions about radiometric dating, including this wonderful rant against the idea that most scientists, most of the time, commit scientific fraud in most subjects relevant to the young-earth creationist view of reality. There is simply no excuse for Dave to spew such unsubstantiated nonsense.

If Dave or other creationists are not happy with these radiometric dates, they are perfectly free to repeat the procedure themselves. Why doesn't Dave ask some creationist organization to take a core of their own from Lake Suigetsu and send blinded samples to the same C14 lab? That should already be high on their agenda, if they were indeed a legitimate research enterprise instead of a front for biblical apologetics masquerading as scientific research. We all know that they will never do that, because they never perform scientific tests that they know in advance will go against their pre-conceived dogma.


Yes, but probably not many.”

Yes, Dave. There are many. 

[Now watch Dave's conclusion to this horror story of solipsistic narrow-mindedness:]

"Contrary to firm declarations from Old Earth Advocates that Lake Suigetsu ‘disproves the Genesis timescale’ or that it supports an Old Earth, the evidence favors episodic deposition of laminations. Probably the majority of the laminations were laid during the year of the Global Flood of Noah, with much of the balance being laid during the ensuing Ice Age and the Global Warmup and Melt which followed that several hundred years later."

"Lake Suigetsu seems to fit well within the Flood paradigm"

In summary: Dave manages to run his preconceived notions along the gauntlet of insightful rebuttals from a multitude of qualified commentators, towards the epistemological train wreck that we can behold above.

What we see is the result of Dave going into several discussions about varves and their supporting evidence, especially concerning the Suigetsu varves and their implications, with the foregone conclusion that these sedimentary formations cannot possibly represent true varves. I will go out on a limb and assert that Dave's general reluctance to accept the reality of sedimentary varves does not stem in any way from geological insight, but from a stubborn insistence on the Bible as literal truth.

In his argumentation, Dave almost never directly addresses the coherent and concordant evidentiary support for tens of thousands of Suigetsu varves. Instead, his arguments concern peripheral issues that lie outside the central focus, with some unfounded insinuations about scientific fraud thrown in for good measure. His arguments are being refuted over and over again, which he refuses to acknowledge or simply chooses to ignore.

Through this painful and embarrassing spectacle of a discussion, Dave stoutly maintains his delusions by shutting out all contradictory information. His utter disconnection from reality is manifested in his final "conclusion" about the Suigetsu varves in the imaginary context of a Noachian flood, which in no way follows from any of the evidence that has been up for discussion.

Dave's blog post stands as a glorious monument over an intellectual process that is entirely corrupt to the core. In this process, truth matters not.


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Fukusawa H, Kato M, Fujiwara O. 2002. Changes of eco-systems in the last 500 years caused by human impacts in lake Suigetsu, central Japan. Geographical Reports of Tokyo Metropolitan University 37:41-49

Hammer BK, Stoermer EF. 1997. Diatom-based interpretation of sediment banding in an urbanized lake. Journal of Paleolimnology 17:437-449

Kato M, Tanimura Y, Fukusawa H. 2004. Survival strategy of diatom species living on now-depositing non-glacial varves. Quaternary International 123:21-26

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Sandman O, Lichu A, Simola H. 1990. Drainage ditch erosion history as recorded in the varved sediment of a small lake in East Finland. Journal of Paleolimnology 3:161-169

Staff RA, Ramsey CB, Bryant CL, Brock F, Payne RL, Schlolaut G, Marshall MH, Brauer A, Lamb HF, Tarasov P, Yokoyama Y, Haraguchi T, Gotanda K, Yonenobu H, Nakagawa T, Suigetsu Project M. 2011. NEW C-14 DETERMINATIONS FROM LAKE SUIGETSU, JAPAN: 12,000 TO 0 CAL BP. Radiocarbon 53:511-528

Stanton T, Snowball I, Zillen L, Wastegard S. 2010. Validating a Swedish varve chronology using radiocarbon, palaeomagnetic secular variation, lead pollution history and statistical correlation. Quaternary Geochronology 5:611-624