Thursday, April 30, 2009

Mavrick scientists: the good, the bad, and the ugly

It has been an interesting few months for rogue geoscientists. The maverick scientist is an icon of popular culture, despite being almost as mythical as a genteel cowboy, or a complete stratigraphic section. Additionally, the number of wannabe lone geniuses, whether delusional crackpots or slickly packaged corporate mouthpieces, far exceeds the supply of genuine articles. Never-the-less, the real deals have been having a good autumn (or spring, since the ones in the news are American).

To clarify, a maverick (or rogue) scientist is a person who advocates a scientific position that is contrary to mainstream though on that issue. For example, I had a grad school professor who didn’t believe in hot spots- he was of the opinion that the potential temperature of MORB was systematically undercalulated, and that a correct value put OIB and MORB within a few tens of degrees. Needless to say, this didn’t go down well in the geophysics side of the building.

As scientific knowledge advances, competing theories will gain supporting or contradictory evidence. This, in turn, will change the number of people who accept one hypothesis or the other. If a particular hypothesis end up being defended by very few stubborn individuals against an overwhelming horde of scientists and data, that’s when those few can be considered to be mavericks.

The first maverick geoscientist of recent note is Hiroshi Ohmoto, of Penn State University. Professor Ohmoto is a long and tireless advocate for oxygen in the Archean atmosphere and hydrosphere, despite the mainstream opinion that surficial conditions were generally reducing during that time. The recent Nature Geoscience paper (for which he is last, but corresponding, author) is just one in a long line of papers which present evidence for sulphur and Iron in high oxidation states in early sediments.

While the surficial conditions of the early Earth are very important for mineral exploration in Archean terranes and the early evolution of life, the Archean isn’t something that many people get emotionally attached to. For that you need volcanoes, dinosaurs, and massive cometary impacts. And that brings us to our second maverick:

Gerta Keller’s group at Princeton has an about-to-be published paper suggesting that the terminal cretaceous extinction event was caused by volcanoes, not the Chicxulub impact. This has caused an interesting ruffle in the blogosphere.

At their best, Mavericks force mainstream scientists to reassess their assumptions and double check their observations. This is a good thing, and excellent examples of scientific discussion of this type can be found at Kim or Survat’s blogs. The worst behavior of scientists behaving badly is also brought out, as is seen in the ad hominem attack of ‘Avondale’ in the comments of the Universe Today article.

So how do you tell the difference between a maverick and a crackpot? For me, the difference is in the data. If the investigation undertaken produces a dataset that is complete enough and good enough for use by researched pursuing investigations unrelated to the maverick’s pet theory, then they are still doing good science. If, however, their work is useless except in the specific context of the point they are trying to make, then to me that’s where you gotta start wondering.

Wednesday, April 29, 2009

Score one for the survivalists

For the past three months, the liberal educated elite has been heaping scorn on the small but loud minority of disgruntled conservatives who have been stockpiling cans, throwing away tea, and getting ready to barricade themselves in their homes, or the nearest convenient cave, if they've been foreclosed on.

Then, what do you know, a pandemic strikes, and these same elites are now asking us if we're prepared for the forced closure of schools, shops, and workplaces.

It's a shame this plague is related to swine, since irony tastes best with bacon.

Friday, April 24, 2009

Administration selects chimpanzee to head NASA

In a surprise move, the White House has selected Ham the chimpanzee to run NASA. In a brief statement, the White House press secretary said, “As this country’s first astronaut, this great ape has shown the same courage and commitment as our greatest space heroes. We have no doubt that Ham will have a positive impact on the agency. Despite years of training, chimpanzees have never developed the cost overruns, design mismanagement or political pork barreling that have typified recent NASA endeavors.”

In response to the accusation that all human candidates had either declined the job or been blocked by short-sighted politicians, White House press secretary Robert Gibbs said simply, “It’s a jungle out there.” Having been dead for 20 years, Ham declined to comment for this article.

Thursday, April 23, 2009

Looking for the next best thing

With my contract set to expire at the end of June, and Geoscience Australia looking at a blanket renewal ban in the face of their predicted staffing cuts, I’m hitting the job market again.

Given the current economic climate, I’d by lying if I said I had the ability to pick and choose. Still, my career to date has been more about the journey than the destination; its trajectory is best described using Brownian motion. Setting goals and working towards them has never really worked for me, but that doesn’t mean I shouldn’t at least think about some of the broad differences in various types of employment.

1. Academics. The good thing about academic work is that the projects can be really, really interesting. There is some really cool stuff going on out there, and if you can get on the right project, that’s great. However, my inability to write papers means that I am unlikely to ever do anything other than work on other people’s projects, and the pay is pretty lousy as well.

2. Industry. The think I loved about working in exploration was the sense of accomplishment that accompanies the end of a successful project. However, the work is extremely demanding, and not always intellectually stimulating. It can also be tough on the family.

3. Government. The difference between this and industry is that for Government work, you don’t have to get up before dawn and work until 10 at night. Not surprisingly, it is less rewarding, both monetarily and in terms of accomplishment. On the other hand, it is great for having a life outside of the job- which is tempting now that LLLL is walking, talking, and fun to be around.

Sometimes I think it might be fun to write a book or do something completely off the wall, but how to monetize such activities in the short term is not obvious to me.

Any suggestions?

Wednesday, April 22, 2009

Luke Missed

Recent NASA imagery has revealed the details of ring formation around a giant planet in a galaxy far, far away (click to enlarge).

For those of you not used to interpreting remote sensing images, an annotated version is posted below:

Maybe next time he will use the targeting computer.

Image from NASA, via the big picture.

Monday, April 20, 2009

Geology action heroes

Apparently, Julia, Kim, Silver Fox, Johannes, the Lost Geologist, Ian, and Garry have been showing and/or listing all the stuff they take to the field. I don't really see what the big deal is; as far as I can tell, being a field geologist is just like working in a cubicle. You type on a computer all day:

Friday, April 17, 2009

My God, it’s full of stars

The Kepler terrestrial planet finding telescope just released its first light picture. According to the mission designers, about 50 of these stars will have earth-sized planets in an orbit with similar insolation as we have. I’m guessing that after removing oddballs due to unusual stellar compositions and eccentric orbits, there will be fewer that are truly earth-like. But as with all experiments of this type, the coolest thing we find will be something we haven’t thought of yet.

Anyway, now that the starscape is out, I’d like to start the first internet planetary betting pool. The rules are simple. Have a look at the full-scale image. Pick a star. The person who selects the star with the most earth-like planet wins.

Now, it may seem like there are a lot of choices there. I haven’t counted them myself, but I read that there are about a quarter million stars in this picture. But think of it this way. One in a quarter million is way, way, way better odds than the lottery. And in this pool, the winner gets shouted to a pan-galactic gargle blaster by each and every one of the unsuccessful players. What could possibly go wrong?

My guess is the star at 4891, 3691.

Blood Emeralds

Been longing for a low Z gemstone that finances Islamic terrorism? Here's your chance.

From the New York Times:

Two dormant emerald mines have reopened under Taliban control. The militants have announced that they will receive one-third of the revenues.

Monday, April 06, 2009

Mutual replacement reactions in alkali feldspars II: trace element partitioning and geothermometry

ResearchBlogging.orgWhen I was taking care of the upstairs ICPMS lab back in my former university life, I would occasionally pick up stray orphan scientists who were interested in some mass spectrometry. These are people collaborating with ANU scientists on non-mass spectrometric matters, who want to get the trace element composition of something, but aren’t hooked up with one of the analytical gurus.

Ian was one such fellow. I think he was mostly here doing TEM work or something, but he came into lab one day wanting to do some laser work- something on alkali in feldspars.

Feldspars contain weight percents of alkali, so this didn’t sound terribly interesting. I set the machine up, tuned it up. OK, is there anything in particular you’re interested in?” I asked.

“I’ll need the smallest spot you can give me.”

I wasn’t a big fan of our small spot- it had 1/14th the area, and thus 1/14th the signal, of the standard size. “Why so small?” I asked.

“I’m trying to analyse exsolution lamellae. Also, I wouldn’t mind getting good numbers on rubidium, cesium and thallium.”

To make matters worse, it was a evolved unit from a layered intrusion, so the trace element compositions were way lower than from a granite.

What had been a painfully routine day had just turned into a challenge.

Fortunately, it was a challenge for which I was prepared. Rb and Cs are notorious in laser systems for having high and variable backgrounds due to reionization off the back of the skimmer cone from ejected electrons. We had a grad student who was looking at Rb and Cs in primitive, depleted melts, so I had been working on this problem for over a year. Suddenly, I had an application for all the work I had been doing.

So, I blew off everything else I had planned to do on what was supposed to be a routine out-of-the-lab-by-morning-tea day, converted everything into low detection mode, put the machine back together, tuned it up, checked the backgrounds, and off we ran. With enough trial and error, We eventually got a machine state and a run table that got most elements detectable most of the time, and by the end of the day the signals were looking semi-respectable. Cs in the albite ended up being too low for us to see, but everything else we got decent detections for. The next day was productive, and by the time we finished it was almost routine. Charlotte did the data reduction and Ian interpreted and plotted all of it up, so I never actually saw what the results meant. When I finally got the draft, I was astounded at the outcome. It’s a natural system, and yet it behaves just like it ought to. Who’d a thunk that?

Of course, the papers describes the analytical procedure used to collect the counts. But counts don't make a signal, counts in excess of background do. And while I'd love to tell you how the background was reduced, that paper just got rejected.

The abstract and word cloud are below:

Perthitic alkali feldspar primocrysts in layered syenites in the Klokken intrusion in South Greenland, underwent dissolution–reprecipitation reactions in a circulating post-magmatic aqueous fluid at *450_C, and are to a large degree pseudomorphs. These ‘mutual replacement’ reactions provide a perfect natural experiment with which to study trace element partitioning between sodium and potassium feldspars growing simultaneously. The reactant ‘phase’ was a cryptoperthitic feldspar consisting of low albite and low microcline in a coherent sub-lm ‘braid’ intergrowth and the product phases were ‘strain-free’ incoherent subgrains of low albite and low microcline forming microporous patch perthites on scales up to 200 lm. The driving force for the reaction was reduction of coherency strain energy. The mechanisms of this process are described in Part I. Five mixed braid perthite–patch perthite crystals were analysed for major and trace elements using laser ablation-inductively coupled plasma mass spectrometry with a 19 lm beam diameter. This gave bulk analyses of the braid texture, which were in the range Ab73–54Or45–27An4.3–0.8, but could resolve Ab- and Or-rich patches in patch perthite. The major element bulk compositions of the crystals were retained during the replacement reactions. Major components in patches plot on tielines in the Ab–Or–An ternary system that pass through or very close to the parent braid perthite composition and indicate local equilibrium on the scale of a few tens of mm. Many trace elements, including REE, were lost to the fluid during the deuteric reactions, but the effect is large only for Fe and Ti. Cs, Pb and Sr were added to some crystals. Plots of log distribution coefficient D for Rb, Ba, Pb, Eu2?, La and Ce between Or- and Ab-rich patches against ionic radius are straight lines, assuming eightfold coordination, and to a first approximation are independent of ionic charge. K also lies on these lines, and the smaller ions Na and Ca lie close to them. The best linear fits were obtained using ionic radii for [8]K and [8]Ca, but there is ambiguity as to whether [7]Na or [5]Na is most appropriate. The linear relationship shows that the listed trace elements are in the feldspar M-site rather than in inclusions. Tl is in M although an exact D could not be obtained. The very large Cs ion partitions strongly into the Or-rich phase but its D value appears to be less than predicted by extrapolation. The near-linearity arises because partitioning is occurring between two solids into sites which have similar Young’s moduli, so that the parabolas that normally represent trace element partitioning between crystals and liquids (which have negligible shear strength) approximately cancel out. Ga and Be are in T-sites, as well as some of the Fe and Ti present, although part is in oxide inclusions. The site of Sc is unclear, but if structural it is likely to be T. Partitioning on M-sites is a potential geothermometer but because the effective size of the irregular M-site is defined by its K and (Na ? Ca) contents, which are controlled by ternary solvus relationships, its calibration is not independent of conventional two-feldspar geothermometers. Trace elements may however provide a useful means of confirming that feldspar pairs are in equilibrium, and of recognising feldspar intergrowths produced by non-isochemical replacement rather than exsolution. Two-feldspar geothermometry for the ternary phases in the low-albite microcline patch perthites gives temperatures above the stability range of microcline, markedly so if a correction is made for Si–Al ordering. This is probably because current geothermometers are too sensitive to low concentrations of An in ordered Or-rich feldspars. This interpretation is supported by two-feldspar assemblages growing at known temperatures in geothermal systems and sedimentary basins.

Wordle: Parsons et al. 2009

Parsons, I., Magee, C., Allen, C., Shelley, J., & Lee, M. (2008). Mutual replacement reactions in alkali feldspars II: trace element partitioning and geothermometry Contributions to Mineralogy and Petrology, 157 (5), 663-687 DOI: 10.1007/s00410-008-0358-1

Thursday, April 02, 2009

Why do we publish papers?

I recently had a short technical note rejected by JAAS, wrote a bitchy self-indulgent blog post about it. Then through the miracle of delayed posting came back and revisited it before it went live. So, in an attempt to create something productive (and marginally less self-indulgent) out of the experience, I’d like to look into the final comment of the first reviewer:

2g. References: I could locate but not open Geostandards Newsletter and Geostandards and Geoanalytical Research journals. I could not find ICP-MS Journal 2000 (refs 1 and 1-10). Ref. 11 is not complete. I had also no access to refs. 4-7, 12, 13. Ref. 14 is missing.

Geostandards newsletter, which became GAGR in 2001 or so, was the publication referenced in numbers 2, 3 (mostly), and 9. Number 8 referenced an article in JAAS, the journal for which this person was reviewing. How many does that leave?

In reality, of course, it doesn’t matter if anyone ever reads papers. Papers are just a way ot scorekeeping for promotion reviews of professional academics. Back in the 19th and 20th centuries, however, journals were actually used for the dissemination of scientific information. I’m not old enough to know what that was like, but it does make me wonder:

If non-academic scientists get all old-fashioned and traditional, and feel the urge to give their colleagues tips, what is the point of trying to publish papers if even the people who review the papers can’t read any of the work on which the research is based?

The reference list is attached. Observant readers may note that my likelihood to be taken seriously as a scientist might improve if I could successfully demonstrate the ability to count to three.

1 C. Tye, K. Sakata, ICP-MS Journal 2000, 8, 7.
2 S. M. Eggins 2003 Geostandards and Geoanalytical Research 2003, 27, 147–162
2 K Sakata, N. Yamada, Naoki Sugiyama Spectrochimica Acta Part B, 2001, 56, 1249-1261.
3 K. Govindaraju. Geostandards Newsletter 1994, 18, 1-158; S.M. Eggins, J. D. Woodhead, L. P. J. Kinsley, G. E. Mortimer, P. Sylvester, M. T. McCulloch, J. M. Hergt, M. R. Handler. Chemical Geology 1997, 134, 311-326; M. D. Norman, W. L. Griffin, N. J. Pearson, M. O. Garcia, S. Y. O'Reilly, Journal of Analytical Atomic Spectrometry, 1998, 13, 477-482; R. W. Hinton, Geostandards Newsletter: The Journal of Geostandards and Geoanalysis 1999, 23, 197-207; S. Gao, X. Liu, H. Yuan, B. Hattendorf, D. Günther, L. Chen, S. Hu, Geostandards Newsletter: The Journal of Geostandards and Geoanalysis 2002, 26, 181-196.
4 S.-s. Sun W. F. McDonough. 1989 Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes Geological Society, London, Special Publications; v. 42; p. 313-345
5 J. Longhi, American Journal of Science 1987, 287, 265-331.
6 D. L. Hamilton, D. M. B. Henderson, Mineralogical Magazine 1968, 36, 832-838.
7 S. Eggins, R. Grün, A. Pike, J. M. S. Shelley and L. Taylor, Quaternary Science Reviews 2003, 22, 1373–1382.
8 H. P . Longerich, S. E. Jackson and D. Gunther, Journal of Analytical Atomic Spectrometry, 1996, 11, 899-904
9 N. J. G. Pearce, W. T. Perkins, J. A. Westgate, M.P. Gorton, S.E. Jackson, C. R. Neal, S. P. Chenery, Geostandards Newsletter, 1997, 21, 115-144.
10 C. Tye, K. Sakata, ICP-MS Journal 2000, 8, 7.
11 I. Parsons, C. Magee, C. Allen, J. M. S. Shelley, M. Lee, Mutual replacement reactions in alkali feldspars II: Trace element partitioning and geothermometry. Contributions to Mineralogy and Petrology. In Press.
12 A. Kallio, T. Ireland; “Silicate melt inclusions in komatiites as potential indicators for crustal growth”. 2006 16th annual Goldschmidt conference.
13 J. D.Stopar, G. J. Taylor, and M. D. Norman 2007 Aqueous alteration in Naklite MIL 03346: LA-ICPMS and Raman spectrometry. 7th International Mars Conference.

* * UPDATE * *

Can you find the references listed above? If so, can you read them? There are polls to the right! -->