Lost Diamonds and Disappearing Impact Evidence
In October of 2008, a dramatic documentary scene was shot in a microscopy lab at the University of California, Santa Barbara. Hexagonal nanodiamonds (lonsdaleite) were found exactly where predicted in the Greenland ice sheet. This provided apparent proof of the Younger Dryas impact hypothesis only one year after it had been published. The remarkable breakthrough brought one researcher to tears. After fourteen years this amazing discovery has never been reproduced. Why not?
PBS’s NOVA series provided financial support for the fieldwork by three authors of this paper (Andrei Kurbatov, Paul Mayewski and Jorgen Steffensen) to collect samples from the Greenland ice sheet. The timeline of the documentary suggests that this trip took place in late July and/or early August of 2008. According to the sponsor, in their documentary, the sample preparation was performed singlehandedly by one coauthor (Allen West).
Here are links to the documentary and transcript.
Younger Dryas impact hypothesis researcher Allen West prepares samples for the electron microscopy discovery scene in in the 2009 NOVA documentary “Megabeasts’ Sudden Death.”
The transcript of the documentary reads as follows:
“This iridium is a tantalizing clue, but, just like at the black mat, there's no smoking gun, because the levels are low. Now it comes down to the nanodiamonds, which are also the hardest to process. Searching through samples from a 17-meter trench for evidence that is a million times smaller than a grain of sand is a very, very painstaking process. That job fell to Allen West… When the meticulous work is finally done, and West has managed to prepare samples for the transmission electron microscope, NOVA asked Paul Mayewski to join James Kennett and materials scientist Chris Mercer, at U.C. Santa Barbara to have a first look at the evidence.”
Younger Dryas impact hypothesis researcher James Kennett reacts to an electron microscope image showing nanodiamonds in the 2009 NOVA documentary “Megabeasts’ Sudden Death.” According to the narrator, “These black specks are nanodiamonds in an extraordinary concentration in this one slide.” Kennett describes what he’s seeing and gives his impressions, “This has huge implications. There's no way you are going to get these kinds of particles in the ice sheet unless they are raining out of the atmosphere. If these indeed are diamonds, then this is a remarkable breakthrough. This is art. This, to me, is a Mona Lisa image, as far as Earth sciences goes. I've never seen anything like this before. This is exciting to me, very exciting. I'm looking for cubics on the list and here's hexagonals coming. I'm saying, ‘Hexagonals in Greenland?’ And yet here it is, alive and true in the Greenland ice sheet.” Later, he describes his reaction, “Exciting is really not the word. It's an experience you usually don't have much in your scientific career. Moments of intense discovery are very emotional for scientists. When scientists make discoveries that they think are really important breakthroughs, if you like, ‘eureka moments,’ there's an elation. There's an elation, an emotion. These were emotional moments. The hypothesis predicts that the diamonds should have been there and there they were.”
According to the documentary timeline, the UCSB scene was shot in October of 2008, within two or three months of the fieldwork to collect the samples.
Two coauthors of this paper (Douglas Kennett and James Kennett) returned to in Greenland to collect more ice samples in August, 2009, a full year before Kurbatov et al (2010) was published.
James Kennett (left) and Douglas Kennett collect samples from the Greenland ice sheet in August, 2009. Figure 3 from the book “Deadly Voyager” by Younger Dryas impact hypothesis advocate James Lawrence Powell.
By September, 2010, the samples they brought back were in the lab for processing. Kurbatov et al (2010) made an apparent reference to this effort in the section “Future work” which stated:
“The data presented herein result from a preliminary study. The discovery of a potential postglacial peak in NDs in the Greenland ice sheet is exciting, and although a few unanswered questions have arisen, we are presenting our results to stimulate further investigation and debate. For example, this study was undertaken using Greenland ice samples taken at relatively coarse resolution, and, to significantly refine the findings presented here, higher resolution sampling is needed. Further areas of potential exploration should include: (1) more precise dating through use of d18O; (2) more detailed geochemical time-series measurements, including for osmium and iridium; (3) utilization of improved diamond-extraction procedures to minimize acid-resistant amorphous carbon, which currently limits available analytical procedures; and (4) expanded analyses of diamond allotropes, such as by Raman spectroscopy. All of these analyses require more extensive, higher resolution sampling in Greenland.” Unfortunately, this future work still appears to be pending after 12 years, suggesting one or more negative results that were never published.
Kurbatov et al (2010) also included an appendix with the section “Concentrating nanodiamonds from ice” which solicited independent confirmation of the results by stating, “A detailed protocol is provided so other researchers can adequately test the results presented herein.” I immediately responded to this solicitation and invitation for more investigation and debate by requesting samples. I sent requests to coauthors Paul Mayewski, Allen West and Ted Bunch. All declined for various reasons, so I asked for clarification. On a Sept. 9, 2010 coauthor Ted Bunch, apparently speaking on behalf of the other authors, sent me email giving two reasons: “First, you have been hostile to the YDB impact from the start,” and “Second, I thought that I made it clear that our diamond grid samples have been promised elsewhere. That is all we have – there ain’t no mo!” He went on to state that many others had already requested and received samples, “The impact team has sent YDB samples all over the world to requesters for their studies. We can’t give what we don’t have. To obtain these Greenland samples cost tens of thousands of dollars and huge efforts, in addition to costly sample prep and analyses.” Bunch made no mention of the fact that the team had just returned from Greenland with more samples, and I didn’t become aware of the existence of more material until many years later.
In the twelve years that have passed since this paper came out, I have not seen any published confirmations based on the samples that were sent all over the world, nor have I seen any publication based on the samples that were collected in 2009.
According to the Kurbatov et al (2010) abstract, “From that layer, we extracted n-diamonds and hexagonal diamonds (lonsdaleite), an accepted ET impact indicator, at abundances of up to about 5 × 10^6 times background levels in adjacent younger and older ice.”
That statement is now contradicted by coauthor Allen West, who recently wrote in an email, “The only problem we encountered was with the lonsdaleite, simply because there were too few of them. We ran every test available… but because there were a few tests we couldn't run, we decided to call them ‘lonsdaleite-like’."
Unfortunately, this change of opinion does not seem to have been published, and reviewers do not seem to be aware of the apparent retraction by the coauthor who prepared the samples for one of the primary findings of Kurbatov et al. 2010). In his 2020 book, “Deadly Voyager,” James Lawrence Powell wrote, “In August 2010 in the Journal of Glaciology, the four scientists and co-authors published, ‘Discovery of a nanodiamond-rich layer in the Greenland ice sheet.’ They confirm the presence of lonsdaleite among the nanodiamonds in the Greenland ice at the YDB, noting that is, ‘the first highly enriched, discrete layer of [nanodiamonds] observed in glacial ice anywhere, and its presence indicates that ice caps are important archves of ET events.’” A 2021 review by M.B. Sweatman states in support of the YDIH, that “…Kurbatov et al. (2010) claimed to find abundant nanodiamonds, including Lonsdaleite, at the Younger Dryas boundary at Kangerlussuaq, on the margin of the Greenland ice sheet.” In his 2022 review, Powell wrote, “Kurbatov et al.[65] reported ‘the discovery in the Greenland ice sheet [of] n-diamonds and hexagonal diamonds (lonsdaleite), an accepted ET impact indicator, at abundances of up to about 5 × 10^6 times background levels in adjacent younger and older ice.’” The age control needed to be improved, they noted, but ‘Using a preliminary ice chronology based on oxygen isotopes and dust stratigraphy, the ND-rich layer appears to be coeval with ND abundance peaks reported at (YDB) sites.’” The reviewers, and now the readers of these reviews, remain unaware that the consensus of the authors of this paper appears to have shifted since 2010.
Because this 2010 paper still has enormous influence on the acceptance of the YDIH by non-specialists and the lay public, I think it is important for the authors to make some clarifying statements on Pubpeer in response to the following questions.
Is it indeed the policy of the paper’s authors to withhold samples of Greenland ice collected from the putative YDB layer from independent researchers who are perceived to be “hostile to the YDB impact” as stated by coauthor T.E. Bunch?
Is it true that as of September, 2010, there were no samples left to provide to independent researchers, as stated by coauthor T.E. Bunch?
Is it true that as of September, 2010, the impact team had “sent YDB samples all over the world to requesters for their studies,” as stated by coauthor T.E. Bunch?
Of the samples that have been sent to requesters, how many have resulted in publications, and how many have provided independent confirmation of the results of Kurbatov et al (2010)?
What were the results of the analysis of the samples retrieved in August, 2009 by coauthors James and Doug Kennett, and why have they not been published?
Has any progress been made on the tasks listed in the “Future Work” section, and if so, when do you anticipate that results will be published?
Scene from the 2009 NOVA documentary “Megabeasts’ Sudden Death” describing the discovery of lonsdaleite (hexagonal) nanodiamonds by the Younger Dryas impact hypothesis team. According to the narrator, “Most diamonds found on Earth are cubic, and have a highly symmetrical structure. But one type they are finding, the hexagonal diamond, is not at all common. The only known way to make these is through a high-pressure blast, such as an impact.”
If it is not in fact the policy of the Kurbatov (2010) coauthors to deny samples to skeptical researchers, and if samples still exist (either from the 2008 NOVA-funded expedition or the 2009 Kennett expedition) I hereby restate my 2010 good faith request for samples for independent analysis by me and my colleagues. Thank you in advance for responding to my questions and for considering my sample request.
Originally published in PubPeer. Authors of Kurbatov (2010) are encouraged to respond, on the record, in that forum.