Thursday, March 22, 2012

Oystein's Contamination Denial

The MEK test in the Active Thermitic Material ... paper was important in that it established that the aluminium in the red/gray chips is in elemental form consistent with the thermite hypothesis, rather than aluminosilicate form consistent with the paint hypothesis. JREFer Oystein is skeptical. He believes that what Harrit et al soaked in MEK wasn't actually one of their "red/gray chips" at all.

Prior to soaking the chip in MEK, Harrit et al generated an XEDS spectrum (Figure 14). As Oystein points out, there are major differences between Figure 14 and earlier red layer spectra. In Figure 14, the oxygen is higher than the carbon, there's much less aluminium than silicon, there's more iron than silicon, and there's a high sulfur peak and a really high calcium peak, as well as peaks for zinc and magnesium. Because of this, Oystein reasons that the chip that was soaked in MEK was a different kind of chip from those documented earlier in the paper.

Harrit et al state that "the analysis was performed on the as-collected surface of the red layer". The chip was not cleaned or cross-sectioned, in other words. The spectra Oystein compares this figure to were of fresh red-layer cross-sections.

Harrit et al explain the unusual peaks as being due to contamination. Oystein doesn't buy this explanation:
Basically, to use "contamination" to explain why Fig 14 is so very different from Fig. 7, you need to remove
  • >80% of the oxygen (highest peak)
  • all of the major metal (calcium, 2nd highest peak)
  • 75% of the iron(4th highest peak)
  • 50% of the silicone (5th-highest peak)
  • all of the sulfur (6th-highest peak)
  • all of the Zn
  • all of the Mg
  • most of the Cr
In other words: With the exception of Al and C, you must declare more than 50% of everything in this chip to be "contamination".

Wow. What a handwave Harrit, Jones and Farrer tried there! And ScootleRoyale apparently fell for it!
Quote from Harrit et al: "Prior to soaking the chip in MEK an XEDS spectrum was acquired from an area of the red-layer surface."

The spectrum is of an area of the red-layer surface, not the entire red layer. So you don't have to declare more than half of the entire chip to be contamination, just the area that the beam was focused on!

For comparison, let's take a look at some of the red-layer surface spectra in Dr Millette's report...

MVA Sample L1616, Chip 4

In this spectrum, the oxygen peak is nearly equal to the carbon peak, and the silicon peak is significantly higher than the aluminium peak. Magnesium, calcium and sulfur are also present.

MVA Sample X0135, Chip 2

In this spectrum, the oxygen peak is higher than the carbon peak, and again there is significantly more silicon than aluminium. Calcium, magneiusm and sulfur are again present, along with zinc.

MVA Sample L1560, Chip 2

In this spectrum, the oxygen peak is much higher than the carbon peak and the silicon peak is much higher than the aluminium peak. Once again, there are also peaks for calcium, sulfur, zinc and magnesium.

MVA Sample X0135, Chip 4

In this spectrum, the iron peak is significantly higher than the peaks for aluminium and silicon.

MVA Sample M3451 (uncleaned), Spectra 9, 14 and 16

In spectrum 9 (top), the oxygen and silicon peaks are massive compared to the carbon and aluminium peaks. In spectrum 14 (middle), the oxygen peak is again much higher than the carbon peak. There is also a large calcium peak and significant sulfur. In spectrum 16 (bottom) the calcium peak is even higher, dwarfing even the silicon peak, and the oxygen and carbon peaks are basically the same height.

Using Oystein's reasoning, you could claim that none of these chips are a match for chips (a)-(d) in Harrit et al either. But Millette concluded, after cross-sectioning and SE imaging, that they are a match. It seems the unusual peaks in these surface spectra were due to surface contamination, just as Harrit et al reasoned for their Figure 14.

So what does Oystein believe they actually soaked in MEK? Tnemec primer! Wait so is he saying Tnemec primer contains elemental aluminium? Is he saying that Tnemec primer doesn't dissolve in paint solvent? Oystein's claim makes no sense. The reason Harrit et al soaked a chip in MEK was to compare the result to Tnemec primer!

Oystein does have a point though. The fact that there's no pre-MEK structural analysis is a weakness of the Harrit et al paper. Oystein's criticism is fair. This is why the case for the chips being thermitic isn't rested solely on the MEK test. This is why they did other tests afterwards, such as the flame ignition tests and DSC tests, and analyses of the post-ignition microspheres. In fact, as well as proving that the chips react exothermically, the DSC plots actually provide more evidence for elemental aluminium.

Notice how two of the traces go into the negative at around 620-670 degrees celsius. A small endothermic peak in this temperature range is characteristic of aluminium melting. This suggests that even after the reaction, there was still some elemental aluminium left over in those chips, which then melted.

I've noticed that a lot of debunker responses to the Active Thermitic Material paper revolve around there not being enough data in the paper. The MEK chip in the paper wasn't the only chip they soaked in MEK. Several chips were soaked in MEK but only one was reported on. Also, surface spectra were generated for chips (a)-(d) before they were cross-sectioned, but weren't included in the paper. According to Farrer, similar contamination to Figure 14 was observed in those. The paper is long enough as it is: 25 pages with 33 coloured illustrations - some of which fill an entire page. It could easily have been several times that with all the data they had. In fact, earlier versions of the paper were indeed longer, but the authors were told by peer-reviewers to keep the length to a minimum. You could nitpick just about every scientific paper ever published for not reporting enough data. And that's all Oystein's criticism is.