Wednesday, March 30, 2011

Thoughts on the mining supertax

I originally wrote this blog rough draft 9 months ago. It got shelved because the prime minister to which it refers got sacked, and since then the new PM canceled the policty, had an election, came up with an amended policy, and then as far as I know shelved it. So the personalities involved have changed, but the overall situation has not.

The government unveiled its new overhaul of the Tax system, which include a resource profits tax of 40%. This has obvious implications for geology, since that is the science used to characterize and find all of these resources that provide the profits.

A few caveats:
Firstly, I despise the Prime Minister. I think he’s a smug, micromanaging, precious, condescending, myopic ratbag. I am similarly unimpressed with just about everything his government has done, with the exception of their financial crisis handling, which was OK.

Secondly, I’m gonna ignore the federalism issues here. Currently, mining royalties are paid to the States, as they own onshore resources and only offshore resources are federal. Obviously this federal resource tax would change all that, which is why the phrase “resources owned by all Australians” is repeated a zillion times.

The problem with resource booms in Australia is this: When the resource sector booms, Australia’s trade balance improves, and the Australian dollar gets stronger. This makes non-resource exports less competitive, and thus hurts the non resource-related part of the economy.

Mineral resources are non-renewable. So ideally, the wealth created by mining them should be used to strengthen and diversify the economy. In a boom, the opposite happens, because of currency strengthening and inflation related to industry demand.

So, some sort of boom-retarding economic adjustment does make sense. However, it needs to be done well. There is no shortage of current or historical countries which have squandered their mineral wealth and ended up dirt poor. And, unsurprisingly, it is not clear how this new tax will work.

The Government is notorious for not explaining how its policies are supposed to work. Most announcements are a curious mix of inside baseball terms and pandering platitudes, and all the tax reform announcements which I could find fit this pattern. However, a lot of the funds are earmarked for ‘infrastructure’. This could be useful, or it could be code for Pork. We really have no idea. However, the Government’s inability to communicate how programs work seems to be related to its tendency to pass reforms that don’t actually work, or that get rorted and ripped off. So I see no evidence that this is not such a debacle.

The thing is, it is really easy to actually summarize the problems of a 2 speed economy (export minerals vs. everything else) quite easily. There is no need to resort to condescending half-truths. Instead of repeating dubious talking points over and over robotically, they could actually tie the various current problems together into a compelling narrative. For example:
-Skilled export industries (be it IT, manufacturing, or education) are suffering because the dollar is being inflated by the export boom.
-Home loan rates are going up because higher interest rates are the only tool the bank has to cool off the overheating resource sector.
-Retailers are losing out to overseas online merchants because of the strong dollar
-International tourism (and education) is suffering for the same reason, coupled with the weak buying power of US and European currency.

These are all reported in the media as unrelated problems, and there has been no attempt by anyone to link them to overall macroeconomic management. No wonder they aren’t making any headway.

Saturday, March 19, 2011

Why fuel rods are radioactive

As everyone knows by now, there is a nuclear crisis in Japan. One of the reactors, despite shutting down correctly, has had a number of explosions and has leaked a frightening amount of radioactive material into the surrounding environment. We all know that nuclear reactors produce lots of highly radioactive waste, so hopefully I can clearly explain why.

Every atom has a nucleus, which contains protons and neutrons. The number of protons determines what chemical properties the atom will have, and thus which chemical element it is. Thus, every nucleus with 20 protons is calcium.

In order for the nucleus to be bound together, it must contain roughly equal numbers of protons and neutrons. However, large nuclei need more neutrons than protons.

color coded decay schemes for nuclei
This can be shown in figure 1. This is a chart of the nuclides. The X axis is the number of neutrons, and the Y axis is the number of protons. The little black squares are stable elements. All of the colored squares indicate radioactive nuclei; the color determines the type of radioactive decay.

Radioactive decay is a process in which an unstable nucleus changes into a more stable nucleus, releasing energy in the process. The type of energy released depends on the type of decay.

In figure 1, the yellow and green colors, which are most common in the very large nuclei, indicate alpha decay and spontaneous fission. In both of these cases, the nucleus is too big, and breaks into smaller parts. In alpha decay, the nucleus loses two neutrons and two protons. In spontaneous fission, the nucleus splits into two large pieces.

In figure 1, the blue and pink colors are types of radioactive decay where the nucleus has a ratio of neutrons to protons which is either too high or too low. In the blue scheme, one proton turns into a neutron in one of two processes, called “electron capture” and “beta plus” decay. In the pink area, the nucleus has too many neutrons, and one of the neutrons transforms into a proton by a mechanism known as beta decay.

When a neutron (which has no electric charge) turns into a proton (which has a positive electric charge), it also emits a high energy electron (which has a negative charge), so that the total charge does not change. A particle known as an antineutrino is also produced, but this is harmless. However, many beta decays also release additional energy in the form of a gamma ray, which is a photon, or type of light, that is basically the same as a high energy X-ray.

Large stable nuclei have a higher ratio of neutrons to protons than small stable nuclei. Nuclear fission, the process that powers nuclear reactors and bombs, involves splitting a large uranium (or occasionally plutonium) atom in two by hitting it with a neutron. This releases lots of energy, more neutrons, and creates two much smaller nuclei. If one or more of the neutrons created by fission then causes another atom to fission, then the reaction is self-sustaining, or “critical”.
235U fission products, color coded by abundance

Fission is a messy process, so the new nuclei produced are not always the same. Figure 2 shows the probability of various possible fission decay products. purple-red is the most likely, while yellow is less likely. As you can see from figure 2, Most of the nuclei most likely to be produced by fission lie to the right of the stable elements, and this have too many neutrons. This means that they must decay via the beta decay process, turning protons into neutrons (and emitting beta particles and gamma rays) without changing the total mass number, until the resulting nucleus become stable. Note that the distribution field is somewhat dumbbell shaped- there is a heavy purple blob and a light purple blob, with a red connector in between.
Figure 3. Fission decay products in the main heavy area of fission yield. Decay shifts atoms up and to the left.

Figure 3 shows the closeup of the area near the centre of the heavy purple blob. As seen here, the elements that are far from stability generally decay rapidly, but in some cases the last decay to stable can take many years. The result is that even if the fission process is stopped, the radioactive decay in the recently created fission products will continue to heat the fuel in the reactor, leading to all the problems we’ve seen on the news.

Friday, March 18, 2011

Old-school optical petrology question

Dear Readers,
What are the standard sizes for petrographic thin sections? Americans may answer in inches, of that is their standard. metric sizes would also be appreciated.

I seem to recall 1x2 inch and 1x3 inch from my days of youth, but I can't find any written evidence of that.


Wednesday, March 16, 2011

How genocide becomes the logical thing to do

While the world stands transfixed by the unfolding disaster in Japan, Qadaffi has been systematically mowing down the opposition in Libya. They Egyptian and Tunisian revolutions earlier this year suggested that a freedom revolution might be in the works. But if Qadaffi mass-murders his way back into power, that could all come to a screeching halt. His approach to mass demonstrations- killing everyone- gives modern dictators two choices:

Firstly, they can refuse to shoot, and end up deposed and exiled, like the ex-presidents of Tunisia and Egypt.

Alternatively, they can gun down the protesters, and remain in power.

The emergence of mass murder as a successful regime-preservation measure is not an encouraging sign. However, this technique appears to be catching on rapidly.

The key to this approach is to find soldiers willing to mow down civilians, and to then deploy them with vastly superior military equipment.

Two days ago, the King of Bahrain, which has seen heavy protests over the past month, ‘invited’ several thousand foreign Sunni Arab troops into his country to deal with his Shi-ite protesters. Last night, they decided to take the Qadaffi approach, and cleared the protesters out of Pearl square, setting fire to the protest encampment.

Like Qadaffi, they have also refused to allow medical professionals to access the wounded, barring ambulances, and locking down the hospital. If the approach works, why change it?

Western governments have suggested, to various extents, that it might be nice to prevent this carnage, but their attempts to do so through multinational agencies like the UN have been stymied by governments who have used the kill-everyone technique in the past. And unlike 1986, we seem to be either unwilling or incapable of bombing him again, despite all the trillions of dollars of defense spending and technological advances since that time.

The take home message, of course, is that simply gunning down huge crowds of unarmed civilians will not incur a penalty from the western world that is anywhere near as severe as the penalty of acceding to the people’s demands. So unless there is a sudden and dramatic turnaround in the western response to the Lybian bloodbath, the technique of shooting anyone who gets in the government’s way will become the most logical course of action for a wide variety of regimes. Thus, we will probably see a lot more of this sort of response in the future. Indeed, if tonight’s reports from Bahrain are correct, the Qadaffi approach is already being emulated in other parts of the Arab world.

Is this “change we can believe in”?

Monday, March 14, 2011

Japan disaster

I've been away for a long weekend, and haven't been keeping up with the news. Other people have, though.
Highly Allochthonous has a roundup on the Earthquake.

See links therein for details.

Jeff, the Arms Control Wonk, was in japan visiting the reprocessing facility at the time of the quake, and has decent information on the state of the reactors.

Geoblogger Evy's dad is a nuclear engineer, so she has posted two explanatory interviews.

An commentary on various things I heard on the radio while driving:

1. The hydrogen explosions at the nuclear plants are not the same as little hydrogen bombs.

Hydrogen bombs release nuclear energy bu fusing hydrogen into helium; basically the same reaction that makes the sun shine.

The hydrogen explosions at the Japanese nuclear plants are a chemical explosion caused by hydrogen gas igniting in air.

The hydrogen is released by the reaction of water (or possibly an acid) with a metal (M):

xH2O + M -> xH2 + MOx

Where x is one half the valence state of the oxidized metal.

The reaction can take place at low temperature in the presence of an acid or catalyst, or at high temperature in the presence of pure water. The most likely scenario is that the zirconium metal in the fuel rods are reacting. One kilogram of Zr metal will release about 44 grams, of ~500 liters, of H2 gas, so you don't need much metal to get a decent bang.

It may be possible that the seawater they have been using as an emergency coolant is boiling to produce a hot, highly saline brine that might be able to catalyze oxidation of other metal components. But you'd have to talk to an aqueous chemist and a nuclear engineer to see what metals are present and whether they could be corroded in this manner. The boric acid that they have been adding to absorb neutrons is a weak acid, and should not be able to react with anything in the reactor to produce hydrogen. There was a confirmation of exposed fuel rods this morning.

2. The earthquake in New Zealand did not cause the Japan Earthquake. They are related only in that they involve the western edge of the Pacific tectonic plate, which is sliding past the Australian plate in New Zealand, and under the Eurasian plate in Japan.

3. The uranium in the reactor may well have been mined in Australia. Japan imports uranium from Australia. It also imports natural gas and coal from Australia. It also imports uranium from Canada. I don't know how much of the non-nuclear generating capacity has been damaged, but there have been images of burning natural gas facilities in the papers.

4. I don't buy the suggestions that this quake is a foreshock for a bigger quake. This is about as big as they get, and none of the other 8.5+ quakes that I know of have been followed by similar sized quakes on the same system. On the other hand, aftershocks are likely, and some may be as big or bigger than the NZ quake.

I don't know if this makes a large quake on Japan's southern subduction zone more or less likely. That would not be a significantly bigger quake (it might even be smaller), but it would effect a more densely populated part of the island, so that could be what people mean by 'the big one'.

Sunday, March 06, 2011

Bye-bye butterfly

What sort of spider is this?

Tuesday, March 01, 2011

Mineralogical Society of America proposes a position statement on Asbestos

The Mineralogical Society of America has proposed a position statement on Asbestos. The criteria of position statements, as explained on their website are:

A position statement should express or espouse a principle or policy of timely significance to the MSA community. The position statement should be consistent with the purpose of MSA and supportive of the disciplines represented by and activities undertaken by MSA and its endeavors, including its publications (e.g., American Mineralogist, RiMG volumes), its programs (e.g., Lecture Program, Short Courses), and functions (professional society, membership in IMA, etc.). A position statement, in and of itself, should not put at risk the corporate and non-profit status of MSA or commit MSA to undue financial liability or risk.

The proposed statement on asbestos can be found here. Non-anonymous comments are welcome at that site.