The possible impact of the Icelandic volcanoes on Energy Production

While it is early in the morning in Europe the following picture shows the impact of the volcano in Iceland on European air traffic if you compare Northern (none) and Southern (60) European flights. The blue crosses are airports. The volcano has already had a stunning impact on Europe, although articles about it are already dropping below the lead headlines. There is a thought that the plume may last another five days, and even though the cloud is largely invisible to those who are being impacted by it, the damage by neglecting these precautions could be severe. And given that the British election is on May 6th the impact of a sustained eruption on the debates in the UK, and the result may go beyond just limiting the travel of those who would campaign, to become more dominant with the length of the flight curtailments and the responses to help resolve what are likely to be growing transportation problems.

Status of flights over Europe (flight radar 24).

UPDATE The presence of sulphur dioxide is already obvious to local residents, though there don't appear to be any concerns over its toxicity. And parts of Britain may get some planes back in the air by this evening or tomorrow. I will repeat information on toxicity

WITH ACUTE EXPOSURE, 5 PPM CAUSES DRYNESS OF NOSE & THROAT AND A MEASUREABLE INCR IN RESISTANCE TO BRONCHIAL AIR FLOW; 6 TO 8 PPM CAUSES A DECR IN TIDAL RESP VOLUME. SNEEZING, COUGH & EYE IRRITATION OCCUR AT 10 PPM; 20 PPM CAUSED BRONCHOSPASM; 50 PPM CAUSES EXTREME DISCOMFORT BUT NO INJURY IN LESS THAN A 30-MIN EXPOSURE ... 1000 PPM CAUSES DEATH IN FROM 10 MIN TO SEVERAL HR BY RESP DEPRESSION.

The larger eruptions of Katla, have ejected up to 1.5 x 10^9 cu m of material with a Volcanic Explosivity Index (VEI) of up to 5. For comparison Mt Pinatubo in 1991 ejected 1.1 x 10^10 cu.m. with a VEI of 6.

The Times has an interesting graphic that shows some of the concerns and I am going to use a bit of it to show that the problem may be a little bigger than even the article suggests.

To begin with recognize that Iceland is at the intersection of different plates that together form the shell of the planet. Whereas in some parts of the world these plates are pushing together and riding over each other, in this part of the world they are tending more to separate, so that the magma, on which the plates ride, can make its way up along the joint planes and erupt at the surface.

Map of Iceland showing major volcanoes (The Times of London)


Now what the picture is concerned about is that generally when Eyjaflallajokull erupts so does Kalta, which is right next door. But Katla is a larger system and the eruption is generally much more severe.

Unfortunately what has also to be considered is that there are a whole line of craters, not shown on this map, between Katla and Vatnajokull, which are also a worry. Laki, an even greater threat than Katla, lies along this line.

Iceland's Laki volcano erupted in 1783, freeing gases that turned into smog. The smog floated across the Jet Stream, changing weather patterns. Many died from gas poisoning in the British Isles. Crop production fell in western Europe. Famine spread. . . . . . .

The winter of 1784 was also one of the longest and coldest on record in North America. New England reported a record stretch of below-zero temperatures and New Jersey reported record snow accumulation. The Mississippi River also reportedly froze in New Orleans.

It is at the orange flag in this picture.

(Google Earth)
There is a line of eruption calderas from Katla up to Laki, which is up around Skaftareldar.

Remember that the 3.5 earthquake I wrote about yesterday lies beyond Laki on the line from Eyjaflallajokull, and was centered further north in the Vatnajokull. Some have blamed the weather created by the eight-month eruption of Laki as a possible contributory cause to the French Revolution.

An eruption of that length, ejecting as much material as it may into the atmosphere, would have consequences that go beyond just the ability to survive the noxious gaseous clouds.

The impact of the dust is shown in this picture from the British Met Office, which shows that plume reaching down past Scotland:

Dust cloud passing Scotland (Met Office)

And the consequent distribution at different levels of the atmosphere.

High and low level ash distribution (Met Office via the Guardian)
The agriculture of Europe would be damaged by a prolonged eruption with this distribution, and with it the possible production of biodiesel. Consider that the growth of rapeseed (canola) around the world has been steadily rising over the past few years.


With European countries sitting just behind the leaders.


Somewhere over 4 million metric tons of the crop currently goes to producing biodiesel, mainly in Europe. (Heading up towards 100,000 bd). Losing a year of that crop (and large scale volcanic activity can have an impact for over four years on the climate and the ground chemistry), particularly given the current possible approach of the peaking of conventional oil production, could have an unanticipated impact on overall liquid fuel availability and price.

Unfortunately rapeseed is only one of the crops that will be effected and the significant drop in crop yields does not appear to be getting much attention yet.

Beyond that, there should be a little concern for the wind turbines that are now dotted over the horizon. The concern is with the speed at which the tips travel through the air. The air, that looks clean, will contain small particles of very sharp glass and other volcanic ejecta, that are the primary cause for the grounding of aircraft across Europe. While the aircraft can see very sudden loss in engine power, because of the high speeds with which they encounter the clouds, and the volumes of debris sucked into engines that then fail. (There are also video explanations)

Wind wing tip speeds have been projected to be in the range from 264 ft/sec to 326 ft/sec. At impact speeds over 120 ft/sec the particles from the eruption will start to erode the blades of the turbine. If the eruption continues for weeks, and the turbines rotate in that atmosphere (which looks clear to normal vision) then they will lose surface quality, and perhaps the particles will enter into the generators (as they do on aircraft) doing significant damage.

Thus, beyond the initial inconvenience of the loss of a way to fly (bearing in mind I am supposed to fly to Europe myself soon), there are the longer concerns over both the crops this summer and for the next four, and for the longer term health of the turbines. All in all it is a reminder that there is never a time that Nature, with a little nudge, cannot remind us of the risks of complacency. . (And I suspect that it will not be long before the usual climate change advocates will be dominating the papers with a new set of headlines to get them back on the bandwagon)

A short update on the Iceland volcano and Chinese earthquakes

Because there have been larger earthquakes (indicating possibly the passage of magma) under the ice of the glacier at Eyjafjallajokull and there are now fissures under the glacier, the authorities have issued an evacuation order for the area. h/t Jon at WUWT. There was a 3.1 earthquake two days ago, and there have been two (one at 3.5 and one at 3.0) more recently. The larger one is at the location of the upper green star in the map. It is at the other end of the range of volcanoes that run between the two and have been the source of the large eruptions of the past. The lower star, at Eyjafjallajokull is the one that everyone is concerned about.
(Update the eruption has now started and the evacuation is underway.)

Map showing the latest earthquakes (green means within the last 24 hours, and a star means it is over magnitude 3.0) (Icelandic Met Office) .
The concern at the moment relates mainly to the melting of the glacier, and the resulting floods that will follow. There is not, at the moment, a great deal of evidence of a major eruption further up the line, which is where the big ones have happened in the past. However the linear activity of the recent quakes there, and then the larger one, makes it an area to keep watching. I am keeping a list of the dates, location and sizes of the quakes above 3.0 at the bottom of this post. I am also going to start adding depths, since the northern green star earthquake is only 1.1 km below the surface. However the ash plume from the volcano is starting to cause air traffic problems over Norway.



Update This is the photo of the eruption that mg talks about in the comments:


The comment notes:

The three red arrows show the locations of the eruptions under the ice. The blue arrow points north.

The ice layer was 650 ft thick, before the eruption below it. Flooding that it has caused has already started to give problems. And if you want scale on the top picture Katla, the icecap to the East of yjafjallajokull is 12 miles away and under the Mýrdalsjökull glacier. The new fissure is about 1.2 miles long and the eruption is considered to be 10 to 20 times more powerful than that last week. There are web cameras set up to view the original eruption, and likely also the new one.

I have also just heard about the major earthquake in western China. I was in Xining City and drove around parts of Qinghai Province last year. One of the things that struck me is the number of small coal-fired brickworks, that were producing fired brick, and supplying a change from the mud brick of which most houses were constructed. Sadly that modernization was not fast enough, and most of the casualties are reported being buried under wood and mud brick buildings, though there are some concrete buildings (including a government one) that have collapsed.

Location of the Chinese Quake (BBC )

The area is remote, and difficult to drive around, so that rescue may be more difficult than in the previous large quake, and our thoughts and prayers are with the victims.

While DoE is complacent, DoD worries about Peak Oil

Last Sunday the Guardian carried a review of a recent report by the United States Joint Forces Command in which, hidden on page 29, lies the statement:

By 2012, surplus oil production could entirely disappear, and as early as 2015, the shortfall in output could reach nearly 10 mbd.

The report bases this conclusion, in part, on the poor discovery rate that has been achieved in finding new oilfields to replace those that are beginning to run out of oil. Looking at the alternative sources of energy, it is not convinced that they provide a viable short-term alternative, given the rising levels of capital cost required for their installation at considerable scale, and thus notes and concludes that:

A severe energy crunch is inevitable without a massive expansion of production and refining capacity. . . . . .Fossil fuels will very likely remain the predominant energy source going forward.

It also notes that if the energy problems drive the world into another Depression, that this might lead, as it has in the past, to the rise of totalitarian regimes that sought prosperity by “ruthless conquest.”

The caveat that I have between these two statements is that, grim as they are, they don’t really recognize the totality of the problem. Simplistically energy has two major uses, one is the creation of electric power, and the other is to provide the motive fuels for transportation. The two uses are disparate, and while oil can be used to generate power, in large measure this has been left to coal and natural gas, while oil has been transformed into the various liquids that power cars, trains and aircraft. At the moment there is not a significant volume of world transport that uses coal and natural gas to drive their vehicles. Nor realistically, apart from the campaign by Boone Pickens, is there much move to change the situation.


As some influential parties in Britain perhaps begin to understand that world oil supplies are finite, and beginning to run short, this does not yet appear to affect the Departments either in the UK or the US whose job it is to be concerned and to find ways of answering the problem.

Gail Tverberg’s review of Secretary Chu’s remarks at the Energy Conference in Washington last week, identified that there is no concern in the Department of Energy over coming shortages, and thus the Department can:
a) rely on the market to solve any problems
b) continue to be more concerned about addressing the climate change issue and
c) invest in longer term research which might provide answers in a decade or so.

The Department of Defense does not live in such a world. And it has heard rumblings of concern from earlier reports by the JASON group about rising costs, given that the Department can purchase up to 101 million barrels of fuel a year, and 145 million barrels of total petroleum products as noted by a recent Congressional Research Service Report. When the price of fuel rises, then the officers in charge have to re-adjust their budgets to cope, sometimes at the cost of the overall objectives. New technologies take years, even decades, to implement, and thus answers cannot be left to “blue sky” thinking alone. And older technologies may not be able to muster enough of an answer to meet the demand. I have seen nothing that yet convinces me that the world will be able to produce more than 90 mbd of crude oil and associated fossil liquids. Thus the projection that the world will need over 118 mbd by 2030 reinforces the implication that we’d better start looking for serious answers with a lot more intensity than we have to date.

There is at least some signs that people are beginning to pay attention, recognizing that there is a risk that there may not be enough jet fuel, the Air Force has begun to check out new fuel sources. Next week is Earth Week, and the Green Hornet, an F/A-18 Super Hornet, will be flown with a mixture of 50% regular fuel and 50% biofuel from camelina. The Navy is intent on moving the program forward.

The 'Green Hornet' initiative supports Mabus' energy reform targets, which will increase warfighting capability by reducing reliance on fossil fuels from unstable locations and reducing volatility associated with long fuel supply transport lines. The secretary's energy reform targets include:

- By 2016, the Navy will sail a "Great Green Fleet" composed of nuclear ships, surface combatants with hybrid electric power systems using biofuel and aircraft flying on only biofuels.

- By 2020, at least half of the DoN's shore-based energy requirements will come from alternative sources and half of total DoN energy consumption will come from alternative sources.

"[The flight] will demonstrate that our systems can work on biofuel," Mabus said in his remarks at a recent energy forum at the Johns Hopkins Applied Physics Lab in Laurel, Md. "After it is successful, and we are absolutely confident that it will be; we will move to expand biofuel testing to our marine gas turbine engines and to the engines of our tactical vehicles."

The problem may be in ensuring an adequate supply. As I noted in the earlier review of camelina, it is not getting rave reviews from the farmers that will have to grow it, nor from the State Agricultural Departments that must approve farmers growing either it or canola.

Oregon officials in 2005 restricted canola-for-oil production in the valley to protect the valley's high-value vegetable seed crops. Officials recently announced they are going to renew the prohibitions.
"I would like to grow canola, but the state interferes with that, too," Van Leeuwen said.

Fears are canola will attract insect pests common to canola and brassica crops and that canola will cross pollinate with cauliflower and broccoli, lowering seed purity and eventually driving vegetable seed contractors out of the valley.

There has, however, been a recent MOU between the UDSA and Navy and the Commercial Airlines Alternate Fuels Initiative to examine the potential of camelina as a crop, though there are already some concerns

Preliminary results from Sidney, Mont., suggest that current camelina varieties use about as much water as spring wheat, so growers would still need to leave land fallow in alternate years to build up water or accept possible yield losses for wheat grown in rotation. However, with appropriate breeding and selection for uniform, desirable agronomic and oil quality characteristics, camelina has potential to be a good oil seed crop for planting during fallow years.

In the face of potential problems for any solution, it would appear wiser for those who should be looking to solve this problem to take their collective heads out of the sand and start to be a bit more constructive in their thinking.

The formation of coal and its forms

The tragedy in West Virginia this week, with the loss of 29 miners, emphasized the dangers that can arise in the production of fossil fuels. While the United States mines are, in general, much safer than those of many countries around the world, any death is a loss, and so I thought I would write a short series of posts on coal mining, from its origins to the methods of mining that are used today. Hopefully, as the series progresses, you might get a better understanding of the world in which the modern miner works. I will throw in a little history, since it helps to explain the evolution of some techniques. I intend to cover some of the other uses of coal, beyond power plants. The coal at the Upper Big Branch Mine, for example, is a metallurgical grade coal, used in steel manufacture. The loss of production from the mine is already having an impact in that market.

So, to begin, I am going to chat a bit about the origins of coal, where it came from, and some of the limits on estimating how much there is, and how much we are going to get out of the ground.

On the occasional morning each week I exercise and watch a video to help pass the time. About a year ago I watched the Cosmos series with Carl Sagan. If you get to about 9 minutes into the 10th episode he talks about how the Sun and planets rotate about the galactic center (the middle of the Milky Way) at somewhere around 220 km/sec. (The actual number has recently been increased about 15% to around 568,000 mph). Bear in mind, however, that speed is generally considered relative to something else and so different numbers can be found. This means that it takes about 250 million years (according to Sagan) for the Sun to circle the center, and as it passes around the center it will move through the four major arms of the galactic structure. And as it moves through these different zones, so there are different conditions that the Earth and the Solar System encounter and these changes reflect on the conditions that helped form the rocks that are now beneath our feet.

Geologists have been able to divide the history of the Earth into different epochs, with changing conditions leading to different types of rock being deposited, depending on what the surface conditions were at the time. In those different epochs temperatures varied, with the following plot coming from the Paleomap project.


Basic divisions and temperatures of the geological intervals in the Earth's rock history.

The period that I want to talk about today is known as the Carboniferous. It was some 300 million years ago, and so a bit more than one revolution of the Sun around the Galaxy. Back in those days, about 30 million years before the time of the dinosaurs (which appeared about that 250 million year ago time when the Sun and us were in about the same relative place as we are now) the landmass of the planet was much different than it is now, and Continental Drift had not yet got the continents to their current position.

Great Dismal Swamp (US Fish and Wildlife)

The late Bob Stefanko has written that the Great Dismal Swamp is probably the best current place that represents the type of conditions under which, back in Carboniferous times (about 355 to 290 million years ago) the various vegetative fragments fall into the water, and are slowly compressing to form a layer of peat. The peat layer in the swamp is about 7 ft thick, which may ultimately compress and ultimately convert to about 20 inches of coal. The swamp is slowly sinking, allowing the vegetative mat to continue to deepen and slowly built to a greater thickness. The trees, however, back then did not look quite the same as today.

Illustration of a living tree, parts of which were found as a fossil.

Back in the Carboniferous Bob Stephanko noted that the speed at which the layers formed was likely about twice that at which the current Swamp is growing, and that, due to the different levels of pressure required to form them, it would have taken about 160 years to lay down what is now a 1 ft thick layer of lignite; 260 years for a foot of bituminous, and about 490 years for a foot of anthracite. Since it is more worthwhile to mine thicker coal, and eight-feet is a nice working height, this would have required about 2,100 years of steady growth to lay down the layer of vegetation that formed the Pittsburgh seam in Pennsylvania. The original areas over which these forests and swamps grew were vast, and the cycles of deposition grew as the land distorted, with multiple seams being deposited in some cases, and a single thick seam in others. But how has it survived? How much is really there, and how much can we actually produce?

I thought I would split those questions into several bits, and in this one, I’d try and explain some of the reasons why, while oil companies often get more oil out of the ground than they anticipate, it is often the other way out when you are mining for coal. So, consider, if you will, the map from the site above, that shows back in Serpukhovian times that the planet looked a lot different than it does now.

Shape of the world at the time that the coal seams were laid down.

With all the continents together, as they were, they have had to travel a considerable distance over the past 300-odd million years to get to where they are today. Along the way they have bumped into each other, and in the process caused mountain ranges to rise, and fall, and there has been quite considerable erosion of the surface between times. And when the land fell then the seas would deposit more layers of rock, so that the coal as it was formed by the pressure of the rocks that overlay it, and the increase in temperatures that the coal would encounter as it moved deeper into the earth. These would change the original peat into the different types of coal that we know today. These start with a brown coal, or lignite. This is mined today in Texas, among many other places, and the transformation is not yet totally complete.

The color of lignite is usually a very dark brown . . . .It contains more or less clearly separable pieces of plant material identifiable as lignitized roots leaves, twigs, and tree trunks; but besides this material there is a considerable amount of earthy to dense, more or less friable material that cannot be identified as a botanical entitiy without the aid of a microscope.”

With increasing pressure, heat and time, the brown coal (which often has a very high moisture content) is transformed into a sub-bituminous coal. This may have between 42 and 52% carbon and 19 to 26 magajoules of energy per pound. That in turn, if the conditions exist, will transform into a denser, harder coal that is the most commonly found around the world, bituminous coal. And if the pressure continues, then the highest quality coal, anthracite – at 86-97% carbon may be formed. This latter is relatively rare in coal fields, being less than 0.5% of the coal in the United States, for example.

Even though the original coal material was laid down horizontally, as the continents moved these rocks became folded and tilted. Thus, for example, in Washington State beds, and in Colorado coal seams may end up lying at very steep angles. The geological way of expressing this is to talk about the dip of the seam, that being the maximum angle to the horizontal, while the strike of the seam is the line along the horizontal perpendicular to the dip. Thus beds in Washington State may dip at between 20 and 60 degrees.

Vertical slice through an area of Washington State showing the way that the coal seams dip.

There are considerable problems when the seam gets to dip more than a few degrees. Bear in mind that machines don’t easily move around slopes that are more than fifteen degrees, and you might understand why, for example, it has been very difficult to mechanize the mines of what once were the most productive in the Soviet Union, but now belong to Ukraine. These are the mines of the Donetsk Coal Basin, where

During the communist era , this region produced most of the Soviet Union's coal, and reaped the high wages and prestige that came with it. Statues of miners were erected in squares; villages were named after famous engineers.

The tide began to turn in the last 20 years of Soviet rule, when the flow of funds from Moscow dried up. After communism's fall, the mines were exposed as the money-losers they are, at the same time that economic pressures devastated their customers. In a decade, the demand for Ukrainian coal dropped 45 percent.

Now Donbass is clinging to the two-thirds of its industry that remains. Viktor Yanukovich, the regional governor, said in an interview last month that another 30 of the region's 89 mines would eventually have to close. But he said he needed at least five years to accomplish that and needed an average of $18 million per mine to provide the miners benefits, retrain them and safely close the pits. "I am not against closing down the mines," he said. "But not as it was done before."

Talk of closure is anathema to Anatoli Goncharov, the director of Gaegova mine, which is located in a bleak village outside Donetsk. His mine produces 360,000 tons of coal per year, less than half what it did in the mid-1980s. Because of the steep angle of the seam, half of coal must be extracted by hand, with hammers.

It costs the mine nearly $30 to produce a ton of coal -- $11.50 more than the coal is selling for. Even with $2.7 million in state subsidies last year, the mine failed to break even. The Ministry of Fuel and Energy has put it on a list of pits that cannot be saved, the mine director acknowledged.

(Note that the story is from 2002). At the time the region was being considered as a future source for coal bed methane. There is, for example, a prospectus as part of the methane to markets program.

Coal seams can be mined as deep as 4,500 ft, but the methane and other problems (including keeping the roof from falling in) have made these difficult conditions to work in, so that while there is still coal in the ground, it is becoming increasingly uneconomic, under present conditions, to extract it.

So one of the first problems that the mining engineer has in determining whether to count coal as a reserve is whether or not it is either practical or economic to mine it. This means that, in general, it must be machine mineable, since the productivity of a human miner is no longer sufficient, in many countries, to cover the costs of labor and support.

The second problem is to ensure that there is enough of it. And so before deciding to mine the company will drill cores down to the coal seam over the planned area that will be mined. These don’t, at first sight, need to be that close, since the initial intent is just to see what is there and that it goes out far enough to make it worth while to sink the mining shaft (which costs several million dollars).

However, even the best attempts at accuracy with this planning do not necessarily work out. Consider for example, the case of the mine at Glenrothes in Scotland.

The primary reason for the designation of Glenrothes was to house miners who where to work at a new super coal mine. This was to be the most modern of the day and was built west of Thornton, an established village south of Glenrothes. The Super Pit was named the Rothes Colliery and it was officially opened by the Queen in 1957. Iconic photographs of the young Queen going down the Rothes Colliery in an all-white boiler suit and helmet are still regularly shown in programmes about the royal family. About 5,000 miners were to be required to produce 5,000 tonnes of coal per day, and huge railway yards were established. The pit was to have a working life of 100 years. The planned long-term benefits were to be huge, and the driver for economic regeneration for central Fife. In 1961, 4 years after opening, the huge investment was written off and the mine run down because of un-stemmable flooding.

There were actually a couple of problems at the mine that could not easily have been foreseen by the drilling pattern. If you look back up at the picture of the Washington coal seams you will see the almost vertical line in the middle of the picture, with the black lines representing the coal seams vertically offset one from the other on either side of it. This is what is called a “fault”, and over the course of time the rock was moved to the point that it broke here and created this fracture in the ground. The rock then moved on one side relative to the other. (Like, on a very small scale, the movement that occurs across a major Earth fault when there is an earthquake).


You have mined to x and meet a fault, did the coal go to a or b? How do you know?

With the movement the rock that lies along the fault gets crushed, which can make it easier for water to flow through. So that if some of the rock, on either side of the coal seam, contained water, then when the mining operation reached to fault, then water could flow through the fault into the mine. There is also another problem. Say you are in charge of the driving of the tunnel that reaches the fault. Suddenly, in front of you, the coal turns into rock. You realize that you have hit a fault, but which way did the coal go – did the ground hade (move) down, or up. The rational way to find out is to drill up or down until you find where it went. Well that takes time, and money, but the worst isn’t over yet. Now you have to move the mining operation that say 20 ft that the coal has moved up. This means driving tunnels upwards, then moving the equipment up, and then recreating the mining pattern, and then moving on. All this development has been in rock, so you haven’t been earning any money from the area while this was going on. And if the difference in height is too great, then the area is abandoned for the time being.

What happened at Glenrothes was that the ground had a lot of these very small faults. They were not apparent from the initial cores, which were quite widely spaced, but over a period of four years they were found sufficiently often, and with a lot of water in them, that it became uneconomic to continue to operate the mine. The mine was estimated to have reserves of 183 million tons of coal, to be able to produce a million tons a year, and to have an operational life of 100 years. In the five years of its life it produced around 700,000 tons in total. (The full story of the mine – which had many problems that I have glossed over – can be found in The Disappearing Scottish Colliery by Robert Halliday.)

There are a couple of other problems that happened at Genrothes that are also fairly common, but that can make life miserable for the miner. Let us go back to when the coal was first still vegetation in the swamp. Swamps are not great flat growing areas that are all even. Streams work their way through, cutting channels through the peat and filling them, often with sand, or other material washed down from local hills. There are dirt hillocks and, after storms the land might be flooded with layers of silt, that can be feet thick.

Now move forward some 300 million years. The sand and silt have turned into sandstone and shale, but they did not compress as much as the vegetation. So now instead of there being a nice 8-ft thick seam which the miner has a machine to extract, the coal has a layer of rock in the middle (the silt layer) that is about a foot thick, but that wanders up and down in the seam, and then gets thicker, as it approaches an old river channel so that the two sections of the seam are now about four feet apart. The mining machine grinds off the coal with picks but when these start to run into rock they wear away very quickly, so that mining slows down and becomes more expensive. And then the machine reaches the sandstone filled river channel and things get just a little more difficult.

When two fours are not as good as one eight.

Now the coal is still there, there are a lot of tools to help get it mined that were not around at the time of Glenrothes, and it is not really necessary in all cases that miners be physically present at the machine when it is mining. But some of the time we still haven’t got the answers that would bring some of this coal back to the point where it is considered a reserve. And there is some doubt, therefore, as to what we call a reserve and what not. But we’ll leave that discussion to another day.

California temperatures, GISS USHCN, E.M. Smith and Anthony Watts

This is the day that I am going to look at the temperature records for California. It was the truncation of the number of stations in the GISS analysis that led E.M. Smith to his post, that started me off into taking a significant look into the temperature records. His concern was initiated by the discovery that the number of stations being used by GISS to monitor CA temperatures had been cut to four, all located near the coast. So does this have any meaning? The task begins, as I outlined at the beginning, by getting the data from the 50 USHCN stations and also inputting the data from the GISS stations.

There will be a slight pause while I do this. And after loading in the data from the 54 USHCN stations there are a few observations. Firstly the data from Death Valley is missing three data points (1896, 1897 and 1899). So noting that 1896 was 0.29 degrees above the state average, and that Death Valley is on average 16.62 degrees above the state average, suggests that in 1896 the temp there would have been 75.92 deg. And so we enter that and do the same for 1897, and 1899. And in passing I note that there are a couple of stations (Death Valley and Indio) that are below sea level. Wonder how that will work out. There don’t seem to be that many in the heights, but we’ll see how the graphs plot out. This is the correction that I explained in more detail when I was looking at the data from Colorado and found some values missing.

Now I get the four station data from GISS that Chiefio lists, which are San Francisco, Santa Maria, Los Angeles, and San Diego, which I download from the GISS site and at first none of these are on the GISS list. So I go back to the station locator and type in San Francisco and I get four stations and checking with Chiefio’s list by grid reference the top one is the one he cites. (and it is the one that has data from 1880 to 2010). So the next one on his list is Santa Maria, try that through the station locator and there are two locations, but neither has a full set of data!! In this case it is the lower of the two, which gets me information from 1948 on. Los Angeles data is all there, as is San Diego’s, though again one has to choose the longer history site from the four available. Phew!

OK so what have we got? With the varying conditions in the state (and particularly since we are coming down from the mountains to the sea) I will expect that there will be some influence of longitude, but given the concentration of data along the coast and at low elevations, I am not sure how it will end up. And then there are a lot more towns with larger populations that we have seen in the states we have looked at until now. Checking populations Cedarville was too rural for the usual city-data site, so I got the population from neighborhoodlink . Cuyamaca is a State Park with zero inhabitants (I put down 1). Electra also appears to be on none of the lists – (So looking at the one site with info, I put down 10). Lake Spaulding is a fishing camp (no data – suggest 5).

And having put in all the data (using the elevations of the airports for the GISS stations) one finds some interesting results. Firstly how do the GISS stations compare with the USHCN data?

While the GISS stations are on average 1.6 degrees warmer than the USHCN stations, the difference between the two is increasing:


(Note however that the small number of GISS stations relative to the number of USHCN stations means that when one does a total average for the state the differences induced are quite small.) Even without the GISS station contribution, the temperature in the state has been increasing, though the rate seems relatively constant since about 1900.


The state is a relatively long one, and there remains a strong influence of latitude:


I had expected, since the mountains are on the East and the sea is on the West, that there would also be an influence of longitude.


And that, at any significant level is apparently a wrong assumption.

Hmm! Well how about height, that has been fairly consistent.


And so it is again, though note that those below sea level seem to be even hotter than predicted.

Now one thing that we also can check on, given that there are significantly more stations in this state, is as to whether the scatter in the data is getting worse. This is something that would be suggested by Anthony Watts survey of stations. The premise has been that as the maintenance on the stations declines so the scatter in the results would get worse. This would be reflected in an increasing standard deviation across the stations in the state.


And while there was no such trend in other states, it is very clear and significant in California.

And with respect to the influence of population, I am still seeing that logarithmic fit, with the knee of the curve being at around 10,000 folk. Thus if GISS is cutting off all the influence of towns below that size, and just calling them rural, the evidence continues to suggest that this is a significant error.


Well I also suppose that this is one of the states where there are enough larger cities in the data bank that we can plot this on a log scale:


Correcting the individual temperatures as though the stations were at the center of the state (i.e. adjusting for latitude, as I did last time), one gets:


And then if one looks at the effect of elevation with latitude taken out of the data, one gets:


Again a clear correlation, except that there is a considerable scatter as one gets down to the range below about 100 m. Since this brings in the possible effects of the nearby ocean, and I am not sure how to isolate that at this time, we’ll leave that part of the analysis until we have more information.

The average elevation of California, by the way, is 884 m, and if you look at the plot above you can see that there are only 9 stations (out of 58) that are above that height. So if you do just an average of the data (which is what I have been doing) it will be weighted by the stations below the average elevation, and this will bias the results. By how much? Well we’re going to have to find more data before we can answer than question, and I suspect that it has to do with making adjustments for being close to the ocean.

More explanations of coal mine gas and coal dust explosions

I have been asked whether it would be possible to make mines safer from methane explosions than they currently are. Firstly it has to be recognized that methane is generated with the coal as it turns from the original vegetation into the different varieties of coal, but it depends on how well the coal was sealed into the surrounding rock as to whether that methane is still there. If the overlying rock did not provide a seal, then the gas may have migrated to the surface over the millennia that it took the coal to form. Some of the topic was covered in the article by Tom Maugh discussing methane generation, but I thought it would also help to discuss two different aspects of the story. How a gas explosion could be so devastating, and how one might get the methane out, if possible before mining. If not then how to extract it from the coal before the machines get there.

Because methane is often present in coal mines, miners learned early in their career how to check and see whether there was any around. They usually did this by looking at the flame of the candle or other light they were using to work by. When there was gas present, then the yellow normal flame would be surrounded by a blue cone, the size of which depended on the gas amount present.

Methane caps on a safety lamp flame (Colliery Deputy’s Handbook) (One of the first tests I had as a miner was to be able to recognize the size and meaning of these cones)

When the miner saw the flame cone, he would first wave a shirt or towel to stir the methane into the air, hoping that the concentration would fall below 1%, but if the level built up, he might have to leave, or call for more drastic measures to get rid of it. Back in Medieval times there was an individual called The Penitent, who would wrap himself in wet rags and crawl into the mine with a candle on a long stick. Raising the candle to the roof, he would ignite the layers of methane that would gather there, before the rest of the miners came back into the working. Methane, being lighter than air would gather in the roof, when the air currents were not strong enough to mix it into the air and remove it.

The Penitent – an etching by Hildebrand

Obviously with the gas diluted and layered it would burn, but not explode –what makes the difference? Firstly it is concentration, when the concentration gets above 5% (but below about 15% since above that there is not enough oxygen in the mix) the gas will explode. And so if the gas is desorbing from the coal, or has previously desorbed into cracks in the coal structure, which are suddenly exposed by the mining process, then the gas can come out in an explosive mix with the air. Because the air currents along the face are high, that concentration is not held for long, but it is one of the two necessary conditions.

The second is that a flame source is also needed, and this would most likely be created by the action of the picks on the mining machine as they rotate through the coal, grinding it from the surface.

Picks backed away from the face so that the full pattern can be seen(ACS).

When the shearer is moving down the face that full set of picks will be set into the coal. The coal is broken free by the picks and moved over to the conveyor by the shape of the scroll that is carrying the picks that you see in the picture above. But because of the shape of the picks, as they cut into and break out the coal, they will also crush some of it to a fine powder. Some of this is fine enough (between 2 and 10 microns that it can be breathed in by the miners, and to prevent this the cutting head is surrounded by spraying jets of water that are located and operated to capture and knock down the dust onto the floor of the mine. Thus by both wetting the coal and by ventilation with a lot of air, the mines develop plans to make the area safe.

The problem however is that within the immediate area after the machine has mined the coal, and while the large coal has been carried away by the adjacent conveyor belt, the fine coal is left on the floor. Now when there is an explosion, there is a blast wave that moves down the tunnel faster than the flame front itself. This blast wave can lift up the dust that is lying on the floor and scatter it across the path of the flame front before it gets to that point. Thus a small pocket of methane exploding can generate a cloud of coal dust ahead of itself, which then ignites with a much more powerful explosion, that is self-sustaining as it keeps lifting the coal dust ahead of the blast to continue fueling the propagating flame front.

In order to stop the blast there are two precautions that mines take. The first is to cover the walls and floor with stone dust. This is usually a limestone, and so when you go down a mine you will find that instead of the surfaces being black they are white. Now if the blast lifts the dust, it also lifts the stone dust into the passage, and this stone dust quenches the flame front when it arrives. Near the face they can also place stone dust piles on planks that are set in the upper part of the passage way. This dust has to be fine enough to pass through a 240 mesh sieve. When the blast wave hits the barrier it knocks it over spilling the dust into the air, and again quenching the following flame front. In some mines the dust barrier has been replaced with water troughs that serve the same function.

The barriers are placed in the tunnels close to the face, since this is the area where stone dust can’t be laid onto the floor and walls, since the mining operation prevents it.

While there are a couple of ways of getting rid of the risk (I mentioned last time that using high pressure waterjets to cut the coal instead of picks obviates the heat source required to initiate the explosion) the process that is being increasingly used is to drain the methane from the coal before the mining process begins.

Par of the historic problem with introducing this methane drainage is that it is a different fuel resource than the coal is, and thus the mineral rights to the two may be different. But getting the methane from the coal first, provides the Coal Bed Methane (CBM) that has become an additional source of natural gas. There is a video on recovery that lasts 8 minutes on Youtube, showing how much of the drilling uses the long horizontal drilling that is becoming common for recovering gas and oil in more conventional deposits. It is that process that EPA has already decided does not threaten surface drinking water quality. Already it provides about 7% of natural gas production in the U.S. But it is not always possible to do this drainage from the surface, particularly in mountainous terrain, where it is difficult to get the necessary drilling rigs in place.

And so the gas is often still there when the coal mine is put into production? And at this point, again, based on how much gas there is, and whether it can be economically recovered for sale an analysis will likely be made on whether it would be worthwhile putting in a methane drainage network.

What is most useful is to drill long horizontal holes into the coal before the coal is mined, since in this way there are fewer problems, and the gas recovered is generally of better quality. If these weren’t drilled before mining they can be drilled from the developing tunnels of the mine, though typically these will not reach out as far as those from a dedicated surface drilling operation.

Even if there is not enough gas to make it economic to sell, with higher volumes in the coal it can be cost effective to drain the gas from the seam before it is mined, or as part of the mining process, since this can increase the safety of the mining process itself. In this case drainage holes must be drilled not only into the coal. Because the advancing face causes the coal to crack about 9 to 15 ft ahead of the longwall face itself, these cracks also work their way into the roof. So that gas can be desorbed into the cracks, and is then carried in the fractures that open around the mining operation, not only into but also over the mining operation and into the collapsing rock pile behind the face. Thus to get all the methane out of the vicinity exhaust holes need to be drilled not only into the coal ahead of the face, but also into the overlying rock, to capture all this methane, before it causes a risk.

These exhaust holes are increasingly fitted with monitoring instruments that feed data to a central computer and software that monitors levels of the dangerous gases within the mine so that, when dangerous levels are detected, then the operations may be closed down.

Sadly, however, the instruments are not sensitive enough or in enough places that they can capture any release of gas from small pockets that can ignite, with tragic results. Our thoughts and prayers remain with those who have lost loved ones in West Virginia, and in other recent disasters of this type around the world.

A correction on the Icelandic earthquake location

Hmm! One of the problems with quoting different sources for information is that sometimes I don’t notice when they get things wrong. Thus it was yesterday when I wrote about the location of earthquakes near the Katya volcano. Let me correct the geography, since while there is some concern it is not quite at the stage yet that I thought it was.

Let’s start with an overall map of Iceland from the Icelandic Meteorological Office. This is the overall map of Iceland, which can be accessed to show where earthquakes have happened over the last 2 days.

Map of Iceland showing recent Earthquakes, stars mark those over magnitude 3.

Now zooming in to the area of most activity down near the bottom, one comes to two ice fields, the Mýrdalsjökull and the Eytafyallajokull, with the recent eruption being at the north side of the latter.



You will notice relative to the plot that I showed from Icenews yesterday


That the field that they had marked as Katla is, in fact Eytafyallajokull and that the recent quakes, while progressing toward Katla, which eruption would be the worrying one, is not quite as severe as I had described. (Katla is under Myrdalsjokull. )

Katla location (Google Earth)

The most severe eruptions have come from Laki, which is the orange flag at Skaftareldar in the following, and it is a bit North of the current eruption.

There is a line of eruption calderas from Katla up to Laki, which is up around Skaftareldar.

This should give some better location sense to the eruption and earthquake patterns:

Latest earthquake locations (note that this is changed since the uppermost figure, the site refreshes regularly)

My apologies for the inaccuracy of the previous report, the sense of concern was appropriate, the location of the site was wrong. I will try to do better.

UPDATES
I am going to park subsequent earthquake locations here for a while - yhose bigger than a 3, and where they are, since there was a second one today (13th April) and to see how this might progress I am going to give latitudes and longitudes

So the info is date, latitude, longitude and magnitude (the web site has more information including depth)

1) 4-12-2010, 63.636, -19.544, 3.1 (East side of Eytafyallajokull, apparently under the snow cap, about the same place as the first one).

2) 4-13-2010, 63.627, -19.636 3.0 (depth of 9.6 km)

3) 4-14-2010, 64.413, -17.225, 3.5 (this one is up at the other range of the likely range of erupting volcanoes)

4) 4-16-2010, 66.471, -17.588 3.6 (depth 4.5 km this one is North of the Island)

5) 04-16-2010, 66.47, -17.583 3.0, depth 4.1 km (very close to the one before it so can't be seen on the map.)

6) 04-26-2010 64.78 -17.285 3.3 (depth 2.8 km up around Loki)

7) 04-27-2010 66.396 -18.773 3.5 (depth 7.1 km offshore N of Iceland)

Oh, and while it is relatively minor, there was one on the 28th at Katla - only a 1.5, but it was at a depth of 0.8 km. Let's see if anything else develops around there.

8) 05-06-2010 64.697 -17.322 3.2 (depth 1.1 km this is around Loki again)

9) 05-07-2010 63.697 -23.244 3.3 (depth of 10.5 km off the South western tip of the island)

There were 3 significant earthquakes in the days before 19 May along the fault line North of Iceland followed by

10) 05-19-2010 66.308 -18.852 4.0 (depth 5.9 km)

11) 05-19-2010 66.144 -18.286 3.3 (depth 1.1 km)

12) 05-19-2010 66.321 -18.599 3.4 (depth 4.2 km)

13) 05-21-2010 64.073 -20.562 3.1 (depth 4.5 km)

14) 06-06-2010 66.618 -17.865 3.0 (depth 3.1 km) (offshore North)

15) 06-06-2010 66.482 -17.562 3.4 (depth 9.5 km) (offshore North)

16) 06-21-2010 64.815 -17.281 3.0 (depth 5.8 km) Kistufell which is up near Loki, north of Grimsfjall

17) 06-27-2010 66.721 -17.721 3.7 (depth 1.1 km offshore North)

18) 06-28 - 2010 64.669 -17.353 3.1 (depth 1 km NE of Bardarbunga - up by Loki)

19) 07-17-2010 64.672 -17.426 3.0 (depth 1.8 km, 6 km NE of Bardarbunga - up by Loki)

20) 07-21-2010 66.673 -17.991 3.1 9depth of 12.4 offshore Grimsey - with a whole slew of adjacent smaller ones)

21) 07-22-2010 66.395 -17.822 3.0 (Depth of 1.2 km offshore Grimsey as with the surrounding ones)

22) 07-23-2010 66.650 -17.946 4.1 ( depth of 22.5 offshore Grimsey - continuing lots of little ones)

23) 07-23-2010 66.656 -17.997 4.1 (Depth of 13.4 km offshore Grimsey - near last two)

24) 07-24-2010 64.038 - 21.231 6.4 (depth of 1.3 SSW of Hromundartindi)

25) 07-26-2010 66.676 -17.983 3.4 (depth of 12.7 km 15 km N of Grimsey)

26) 07-26-2010 66.649 -17.933 3.0 9depth of 13.4 km 12.4 km NNE of Grimsey)

27) 08-03-2010 64.429 -17.225 3.0 (1.1 km deep NE of Grimsfjall - near Loki)

28) 08-03-2010 66.689 -17.988 3.6 (14.9 km deep N of Grimsey)

29) 08-04-2010 66.636 -17.961 3.0 (10.7 km deep NNE of Grimsey)

30) 08-12-2010 64.492 -17.741 3.0 (1.7 km deep 3.3 km E of Hamarinn)

31) 08-19-2010 64.741 -17.266 3.4 (2 KM Deep 5.2 km SSW of Kistufell)

32) 08-19-2010 64.742 -17.244 3.1 (3.6 km deep 4.6 km SSW of Kistufell)

33) 08-19-2010 64.749 -17.234 3.2 (depth 2.3 km 3.7 km SSW of Kistafull)

34) 08-19-2010 64.740 -17.24 3.0 (depth 2.9 km 4.8 km SSW of Kistafull) (I.e. N of Bardarbunga near Loki)

35) 08-23-2010 64.705 -17.281 3.4 (depth 0.7 km 9.1 km SSW of Kistafull)

36) 09-14-2010 66.529 -17.808 3.6 (depth of 13.3 km 9.0 km E of Grimsey)

37) 09-14-2010 66.530 -17.812 3.4 (depth of 11 km 9.1 km ESE of Grimsey)

38) 09-14-2010 66.506 -17.794 3.0 (depth of 8.4 km 10.3 km ESE of Grimsey)
All these last 3 were offshore and within 90 minutes of one another. They were followed by a bunch of shallower and weaker ones.

39) 09-19-2010 64,694 -17,309 3,5 (depth of 1 km, 10,8 km SSW of Kistufell)

40) 09-19-2010 65,105 -16,488 3,0 (depth of 1.1 km 5,1 km WNW of Herðubreiðartögl)

41) 09-19-2010 66,377 -17,070 3,6 (1.4 km deep 28,8 km WNW of Kópasker)

42) 09-19-2010 66,349 -17,049 3,6 (1.1 km deep 27,2 km WNW of Kópasker)

The above 4 shallow quakes all occurred within 90 minutes of one another.

43) 09-22-2010 66,922 -18,359 3,5(4.5 km deep 28,7 km SSE of Kolbeinsey)

44) 09-23-2010 64,401 -17,312 3,0(2.9 km deep, 1,9 km WSW of Grímsfjall)

45) 09-25-2010 64,504 -17,762 3,5 (Surface 3,0 km NE of Hamarinn)

46) 09-25-2010 64,504 -17,747 3,9 (0.8 km deep 3,6 km ENE of Hamarinn)
The above 2 seem part of the same process and are ENE of Grimsfjall)

47) 10-04-2010 64,714 -17,320 3,1 (0.4 km deep 9,1 km SW of Kistufel)l

48) 10-04-2010 64,509 -17,749 3,6 (0.8 km deep 3,8 km NE of Hamarinn)

49) 10-07-2010 66,397 -19,509 3,4 (3 km deep 37,7 km NW of Siglufjörður)

50) 10-24-2010 63,488 -23,951 3,0 (1.1 km deep 7,2 km W of Eldeyjarboði) which is way South

51) 10-28-2010 65,165 -19,605 3,7 (1.1 km deep 33,1 km N of Hveravellir)

52) 10-28-2010 65,139 -19,581 3,1 (1.1 km deep 30,2 km N of Hveravellir)

53) 10-31-2010 65,139 -19,540 4,0 (1.1 km deep 30,1 km N of Hveravellir)

54) 10-31-2010 65,162 -19,596 4,0 (o.9 km deep 32,8 km N of Hveravellir)

55) 11-03-2010 64,811 -17,198 3,3 (5.1 km deep 3,4 km N of Kistufell)

56) 11-04-2010 67,202 -16,750 3,8 (15.5 km deep 83,4 km E of Kolbeinsey)

57) 11-05-2010 66,915 -18,099 3,0 (1.1 km deep 36,1 km SE of Kolbeinsey)

58) 11-05-2010 66,574 -18,052 3,4 (9.1 km deep 4,1 km NNW of Grímsey)

59) 11-10-2010 65,703 -16,784 3,0 (3.3 km deep 1,7 km SW of Kröfluvirkjun)

60) 11-11-2010 63,953 -22,071 3,1 (6.9 km deep 5,1 km ENE of Keilir)

61) 11-14-2010 64,260 -16,523 3,0 (1.1 km deep 28,2 km NNE of Hvannadalshnjúkur)

62) 11-25-2010 68,549 -16,687 3,3 (6.4 km deep 176,6 km NNE of Kolbeinsey)

63) 11-25-2010 64,506 -17,579 3,5 (1.1 km deep 11,2 km E of Hamarinn)

64) 12-02-2010 65,096 -16,422 3,1 (1.5 km deep 1,9 km WNW of Herðubreiðartögl)

65) 12-13-2010 63,904 -22,045 3,1 (4.6 km deep 2,1 km NNE of Krýsuvík)

66) 12-15-2010 66,158 -17,840 3,0 9(9.2 km deep 0,9 km S of Flatey)

67) 12-16-2010 66,705 -18,050 3,9 (14.7 km deep 18,3 km N of Grímsey)

68) 12-17-2010 66,459 -17,356 3,2 (6.1 km deep 30,4 km ESE of Grímsey)

69) 12-17-2010 63,882 -19,791 3,0 (9.7 km deep 13,6 km SSW of Hekla)

70) 12-17-2010 66,630 -17,878 3,0 (7.9 km deep 11,4 km NNE of Grímsey)

71) 12-22-2010 66,337 -17,401 3,0 (8.4 km deep 27,3 km NE of Flatey)

72) 12-23-2010 66,663 -17,945 3,0 (11.9 km deep 13,8 km NNE of Grímsey)

73) 12-23-2010 66,614 -17,807 3,0 (1.1 km deep 12,0 km NE of Grímsey)

74)12-24-2010 66,676 -17,985 3,0 (13.5 km deep 15,0 km N of Grímsey)

75)12-24-2010 66,347 -17,509 3,0 (1.1 km deep 25,0 km NE of Flatey)

76)12-24-2010 66,242 -17,250 3,0 (1.1 km deep 22,6 km N of Húsavík)

77)12-31-2010 64,761 -17,178 3,3 (3.5 km deep 2,6 km SSE of Kistufell)

78)01-02-2011 64,757 -17,191 3,8 (2.1 km deep 2,8 km SSE of Kistufell)

79) 01-06-2011 63,627 -23,336 3,0 (2 virtually simultaneous one 1.1 km dee, one 17 km 6,2 km SSW of Geirfugladrangur)

80)01-10-2011 63,587 -23,607 3,7 (10.4 km deep 14,6 km NE of Eldeyjarboði)

81)01-13-2011 64,400 -17,250 3,8 (14.4 km deep 1,2 km ESE of Grímsfjall)

82) 01-25-2011 64,514 -17,667 3,0 (1.1 km deep 97,5 km ENE of Hamarinn)

83) 02-02-2011 64,682 -17,361 3,1 ( 1.4 km deep 9,2 km ENE of Bárðarbunga)

84) 02-03-2011 64,764 -17,266 3,3 (1.1 km deep 3,3 km SW of Kistufell) Not that far from the last one

85) 02-06-2011 64,501 -17,609 3,4 (1,1 km deep, 9,7 km E of Hamarinn)

86) 02-06-2011 64,689 -17,020 3,3 (1,1 km deep 13,6 km SE of Kistufell)

87) 02-06-2011 64,753 -17,256 3,0 (2,7km deep 3,8 km SW of Kistufell)

88) 02-12-2011 64,587 -20,655 3,6 (2,6 km deep 16,0 km SE of Húsafell)

89) 02-12-2011 64,347 -20,711 3,3 (1,1 km deep 6,8 km SSE of Skjaldbreið)

90) 02-12-2011 64,556 -20,636 3,4 (1,0 km deep 17,5 km NNE of Skjaldbreið)

91) 02-12-2011 64,583 -20,618 3,2 (1,1 km deep 17,5 km SE of Húsafell)

92) 02-25-2011 64,402 -17,281 3,3 (1,1 km deep 0,5 km SW of Grímsfjall)

93) 02-27-2011 63,928 -22,034 4,1 (1,1km deep 4,8 km NNE of Krýsuvík)

94) 02-27-2011 63,934 -22,036 3,1 (7,5 km deep 5,4 km NNE of Krýsuvík)

95) 02-27-2011 63,920 -22,030 3,4 (1,6 km deep 4,0 km NNE of Krýsuvík)

96) 02-27-2011 63,892 -22,354 3,0 ( 4,4 km deep, 4,1 km WSW of Fagradalsfjall)

97) 03-02-2011 63,894 -22,052 3,6 (3,8 km deep 1,0 km NE of Krýsuvík)

98) 03-02-2011 63,897 -22,054 3,0 (6,4 km deep 1,2 km NNE of Krýsuvík)

99)03-12-2011 64,505 -17,512 3,1 ( 1,1 km deep 14,4 km E of Hamarinn)

100) 05-21-2011 64,369 -17,201 3,6 (1,1 km deep 5,3 km SE of Grímsfjall)

101) 05-21-2011 64,154 -17,642 3,3 (1,1 km deep 30,2 km ENE of Laki)

102) 05-21-2011 64,366 -17,266 3,0 (1,1 km deep 4,3 km S of Grímsfjall)

103) 05-21-2011 63,905 -18,523 4,6 (1,1 km deep 23,1 km SW of Laki)

104) 05-21-2011 64,049 -17,770 3,1 (3,3 km deep 22,7 km E of Laki)

105)06-05-2011 66,572 -17,830 3,1 (13,1 km deep 8,6 km ENE of Grímsey)

106)06-17-2011 63,642 -19,159 3,3 (1,1 km deep 4,5 km E of Goðabunga)

107)06-17-2011 63,637 -19,108 3,5 (4,8 km deep 6,3 km N of Hábunga)

108)06-18-2011 64,585 -20,619 3,3 (2,1 km deep 17,4 km SE of Húsafell)

109) 07-05-2011 66,242 -16,889 3,1 (5,0 km deep 20,6 km WSW of Kópasker)

110) 07-06-2011 63,638 -23,344 3,1 (10,1 km deep 5,3 km SSW of Geirfugladrangur)

111) 07-06-2011 63,491 -22,937 3,0 (1,1 km deep 26,5 km SSE of Geirfuglasker)