Wednesday, March 27, 2013

Lake Baikal


Located in Siberia, Lake Baikal contains the worlds largest body of unfrozen fresh water; approximately 20% of the worlds total. And at over 1.6km deep at the deepest point it's also the deepest freshwater lake in the world. And that's not all, it's also believed to be the oldest freshwater lake in the world, with estimates placing it at 25 million years old.

Lake Baikal has formed ...in a rift valley created by the Baikal Rift Zone, a divergent plate boundary. So far geologically, there has been no volcanism associated with the rift underneath the lake, but there are hot springs present both on land and under the lake. Close-by volcanic activity on the Udokan Plateau is believed to be associated with the Baikal Rift.

The climate of the Lake Baikal region averages -19°C in the winter and 14°C in the Summer.

Home to over 1600 species of plant and animal (of which more than 80% are endemic to the region) Lake Baikal was declared a world heritage site in 1996. The Eastern side of the lake is also home to Buryat tribes (The Buryats are the largest indigenous group in Siberia and number around 500,000).

For more information click on the links below.

http://whc.unesco.org/en/list/754

http://geology.com/records/largest-lake.shtml

http://www.lakebaikal.org/

http://education.nationalgeographic.com/education/encyclopedia/lake/?ar_a=1&ar_r=3

http://www.volcano.si.edu/world/volcano.cfm?vnum=1002-03-

http://seismo.device.mst.edu/sgao/publications/epsl06a.pdf

Image; Cracked Ice on the surface of Lake Baikal by Daniel Kordan

Viking Spar



A group of French scientists have discovered physical evidence for the use of a “sun compass” from the wreck of a 16th century ship off the island of Alderney, in the English Channel. In a paper published this month, they suggest that a crystal of calcite, found near other navigational instruments at the wreck site, was used to locate the position of the sun, and hence south, by the a...ncient mariners on board. The finding backs up previous hypotheses that this was the method widely used by Viking seamen centuries earlier.

Any amateur (or professional, for that matter) photographers out there will know the potential benefit of using a polarising filter for enhancing your photos. A piece of polaroid in front of the camera lens will darken the sky if correctly oriented, by cutting out light scattered (and then itself polarised) off particles in the atmosphere. A polarising filter is most effective when pointing your camera in directions that are at a compass bearing 90˚ away from the sun. So, if it is mid-day you will find that the polarising filter will show the sky darkest when you face east or west. However, if you’re facing the sun, or have the sun directly behind you, a polarising filter won’t have any beneficial effect for your photos.

It is believed that the Vikings used the same phenomenon as a navigational aid. It seems that the Vikings sailed around the North Atlantic navigating by the sun. Noting the rising, mid-day, and setting sun they could identify south. But how do you manage that when the sun is obscured by cloud? It happens from time to time on the eastern and northern fringes of the North Atlantic, believe me! Well, this is where the polarisation of sunlight that is scattered by water droplets in the atmosphere comes in handy. If you have a polarising filter on your camera, we know that you can identify where the sun is by how effectively it cuts out glare, even when cloudy. One Icelandic saga appears to refer to this effect. It is reported there that King Olaf asked his vassal, Sigurd, the direction of the sun on a snowy day. He then checked Sigurd’s answer by “fetching the sunstone, he held it up and looked at the sky through the stone to confirm Sigurd’s answer”.

So, what stone did the Vikings use for polaroid? Well, it turns out that certain minerals can discriminate between light polarised in different directions. For example, some are “pleochroic” … their colour appears different depending on the polarisation direction of light shining through them (rather similar to polaroid, but usually not as dramatically). Most also show differences in their refractive index depending on that polarisation direction too. While such refractive differences are small for the majority of minerals, there are some that show really strong effects of this type, most notably calcite (CaCO3), also known as Iceland Spar. Calcite crystals can be found as large well-formed rhombs in Iceland (and elsewhere). When light shines through them, it travels faster or slower depending on its polarisation direction, so a single beam of light entering the crystal is refracted into two beams on exit (stay with me here …). This can be seen by placing a single mark on one side of the crystal and looking through it from the other side. The single mark shows up double. The two marks correspond to the two polarisation directions of light shining through the crystal from the sky beyond. Even on a cloudy day, the two marks will have equal intensity if you are looking in the direction of the sun, but one will appear dark and one light if you are looking at 90˚ to the sun. Hey presto! We have an optical compass. Actually, “sky-compass” devices like this have been the subject of patents in the last century or so, and were even used by trans-arctic aircrew in recent history.

So, coming back to the Alderney wreck. The calcite rhomb found in the wreck has been partially dolomitised (Mg replacing Ca in the calcite lattice) which acted to preserve it. No such Iceland spar crystals have been found in Viking sites, however. It is suggested that the reason for the lack of direct evidence of Viking spar crystals is that, as revered objects, they were consigned to the funeral pyres of their owners. Calcite (CaCO3) breaks down to CaO plus CO2 on heating (the process for making lime from limestone, in a lime kiln), so any Viking sun compass treated this way would inevitably have been destroyed. The more recent Alderney sun compass is the first physical proof of the use of calcite for this purpose in ancient times.

Vikings – mineral physics technicians?


Image: calcite sunstone and polaroid filter compared, a montage from www.making-it-up-as-i-go.com and www.cyphertext.net


Links:

http://www.nordskip.com/vikingcompass.html

http://rspa.royalsocietypublishing.org/content/469/2153/20120651.full

Lake Magadi, Kenya


Lake Magadi, the southernmost lake in the Kenyan Rift Valley, is a saline, highly alkaline lake, or "saline pan." The lake has an abundance of sodium bicarbonate, which precipitates as the mineral trona, or sodium sesquicarbonate. Since the lake is in an arid region, most of the water feeding the lake comes from saline hot springs with temperatures near 86°C. The lake has a pH ...of 10 and alkalinity of 380 mmol L-1. Despite the highly alkaline environment, one species of fish (tilapia grahami) and several types of bacteria survive in the water. Natronobacteria are abundant in the lake's salt flats, giving rise to the often-seen pink hue. Research is ongoing to learn more about bacteria that can survive in highly alkaline environments.



http://microbewiki.kenyon.edu/index.php/Alkaline_Lake

Photo courtesy of Lynne Tuller
http://commons.wikimedia.org/wiki/File:Lake_Magadi,_Kenya-5.jpg

Flint: A rock made of life


Flint is one of the oldest materials used by man, shaped by knapping into an incredible variety of tools, used with iron pyrite as a fire lighter, or in early firearms. It is also found in many of England's old buildings, particularly Norman churches. The beginning of our long relationship with this rock is lost in the mists of time, but advanced tools date from at lea...st 1.75 million years ago when our ancestor Homo Erectus roamed the land. Southern England's pebbly beaches are mostly flint, with their magical tinkling noise as the waves of a North Sea storm roll in, carrying their cargoes of driftwood and the odd lump of amber floated over from the Baltic.

In Europe it is usually found within, or weathered out of, the upper Cretaceous chalk formation (deposited between 60-95 million years ago). This chalk started life as a white calcareous ooze at the bottom of a warm, shallow sea. It consists of the excreta of shrimp that ate plankton with calcium carbonate shells (called coccolithophores), and is therefore a form of very fine grained limestone with some mud and volcanic ash mixed in. Our earlier story on Beach head (link below) shows the stunning chalk cliffs found on Britain's southern coastline.

Within the chalk lie many horizons (horizontal beds) of flint nodules. Chert, another name for flint, is a mosaic of micro-crystalline quartz (crystals too small to see) and opal (amorphous silica). It is usually coloured black by organic matter/clay or orangey-brown by iron rich minerals such as haematite, and the nodules often have a thick white coating. These horizons have been used for stratigraphic correlation since Strata Smith's first geological maps in the late 18th century, and they reflect periods of silica rich deposition in the original sediments.

In our recent post on mineral evolution (link below) we discussed the importance of life/rock interactions in the creation of new minerals, here we have a similar tale about the origin of a rock. Flint formed in the complex processes of diagenesis, which transformed the ooze into the soft chalk we see today. The silica came from plankton shells and bits of sponges called spicules in the ooze. These partly dissolved in the water and were precipitated around or replaced a nucleus, often a fossil or worm burrow. It's thought that the silica was first deposited as a gel (see our story on opal, linked below), as it is often found filling sea urchin shells, creating perfect internal moulds. Over time the crystallinity increased as the gel was dissolved and re-precipitated.

The action happened some distance below the surface, where the layer of ooze containing oxygen from sea water met the anoxic layer below. Here bacteria called methanogens were busy eating by stripping oxygen from carbonate and sulphate, extracting the energy for their chemosynthetic lifestyle (some of the methane ends up in clathrates, link to recent story below). Others are feeding by decaying the organic matter in the ooze. The effect of this activity is to create complex gradients in water chemistry and acidity that end up first concentrating and then precipitating the dissolved silica into nodules. These grow layer by layer over a long time until the conditions change as the sediments are gently baked and pressed into rock.
Some scientists think the horizons correspond to radiolarian blooms linked to seasonal or other factors. Others suggest that they mark a pause in sedimentation, when sponges thrived on the sea floor. Flint formation is rarer in today's seas, which have been depleted in silica since the Eocene. The silica richness of Cretaceous seas came from the higher rate of hydrothermal activity in mid ocean spreading ridges as Pangaea broke up.

Flint is therefore made from life's remains, by the action of bacteria during the birth process of a rock. This energetic dance is good illustration of the Taoist concept of jijimuge, which means 'the interpenetration of all things'. We keep on discovering new layers to this concept as our understanding of Earth as a series of interconnected dynamic systems grows.

Image credit: Paul Frogatt

http://www.quartzpage.de/flint.html

http://www.stoneagetools.co.uk/what-is-flint.htm

http://www.westsussexgeology.co.uk/page2-09-4.html

A chapter on the upper Cretaceous rocks of the UK:
http://jncc.defra.gov.uk/pdf/v23chap1.pdf
http://www.guardian.co.uk/science/2011/aug/31/hand-axes-oldest-advanced-stone-tools

You can read our piece on Beachy Head, one of England's chalk cliffs at:

https://www.facebook.com/photo.php?fbid=423328307728219&set=a.352867368107647.80532.352857924775258&type=1

on mineral evolution at: https://www.facebook.com/photo.php?fbid=488752257852490&set=a.487707811290268.1073741830.352857924775258&type=1

about opal formation at:
https://www.facebook.com/photo.php?fbid=474086139319102&set=a.487707811290268.1073741830.352857924775258&type=3&src=https%3A%2F%2Ffbcdn-sphotos-e-a.akamaihd.net%2Fhphotos-ak-ash4%2F485343_474086139319102_1136965089_n.jpg&size=480%2C333

methane clathrates at:
https://www.facebook.com/photo.php?fbid=490062364388146&set=a.490062084388174.1073741836.352857924775258&type=1


Kiss Me! I’m 320 Million Years Old…and I’m Irish! A St. Patrick’s Day Tribute


Everyone is a little Irish on St. Patrick’s Day. To celebrate this historical holiday, let’s take a visit to the Cliffs of Moher, one of Ireland’s most precious lucky charms. Soaring over 200 meters (≈650 ft) above the Atlantic, the Cliffs of Moher were made from the sediments of sandstone and siltstone that were deposi...ted by an ancient river delta into a seabed around 320 million years ago. Over time, the sediments hardened into rock layers which make up the current visible strata on the cliffs’ edges today.

Not only do the strata tell the story of these ancient cliffs, but they also offer a timeline of evolutionary and geological events that took place over millions of years. The uppermost layers of the strata are the youngest rock layers and the bottommost layers are the oldest. Hidden within the bedding are tons of fossils of goniatites and other extinct surface-dwelling / near-surface-dwelling critters. From these fossils, scientists have been able to calculate some of the atmospheric conditions on earth millions years ago, specifically near Ireland in this case.

So when you’re dining on your corn beef and cabbage and drinking dark beer in a local pub, imagine yourself at the Cliffs of Moher and consider its rich history. You can only wish to be so lucky to have a rainbow backdrop during your stay at the cliffs, as in the featured picture, but who knows? When you’re lucky, you’re lucky.


Photo Credit:
Rutger, Deviant Art
http://pixllmania.deviantart.com/art/Cliffs-of-Moher-with-rainbow-268844396

References:
1. http://www.geoneed.org/wp-content/uploads/downloads/2011/05/Module-B4-Information-Sheets.pdf
2. http://www.cliffsofmoher.ie/AtlanticEdge/Rock.aspx?rowid=6684
3. https://www.gsi.ie/Education/Sites+Walks+Field+Trips/Cliffs+of+Moher.htm
4. http://www.prehistoricplanet.com/news/index.php?id=48

ATHABASCA TAR SANDS


If you’ve followed the news, you’ve probably heard a fair amount about the processing of “tar sands” in Canada, as they have become both a major supplier of oil to the U.S. and controversial for many environmental reasons.

Without taking a specific side of the political debates in this post, I thought it would be interesting to cover the geology of this deposit and what exact...ly it is, since that doesn’t get discussed very often. If nothing else, it probably will lead to some lively comments!

The key ingredient in the Canadian tar sands is a material called “bitumen”. Another word for it is asphalt, which is probably more familiar to people. Bitumen is basically a version of petroleum that is solid at room temperatures. It’s fairly sticky, it does flow if you heat it, but it’s like a very thick sludge. In road construction, asphalt is often used as the glue that holds the road together. If you’ve stepped on a recently paved road on a hot day and felt like your feet might stick to the road…that’s asphalt. That’s what’s being mined here.

The bitumen in Canada is a product of several geologic events. First, rocks were laid down and buried that could act as source rocks; carbon-rich rocks that give off oil when heated called kerogen. There is some debate about what exactly the source rocks were, but they must be buried somewhere. Later, on top of the source rocks, an estuarine system developed. An estuary is a place where a river meets an ocean. The river delivers sand and mud, building up thick piles of sedimentary rock, including lenses of sand. These rocks are, in places, known as the McMurray formation, and the sandy layers are the rocks that wind up hosting the “oil”. Next, carbonate rocks were formed on top of the estuarine sediments. The carbonates are important because they’re impenetrable; oil can’t flow through them easily.

Finally, to form oil, something major happened; the Rocky Mountains formed, impacting this area in the late Cretaceous (~65 million years ago). The building of those mountains heated the source rocks to create oil, and created pressure that forced the oil to migrate. The oil moved from the source rocks into the estuarine sands, which are good places to trap oil. The oil was trapped there, finally, by the carbonate rocks above, which it couldn’t migrate through.

All of these are normal processes in oil reservoirs, but something different happened here. The oil in these sediments was shallow, close to the Earth’s surface, and held at low temperature, mostly below 80°C. At these temperatures, bacteria can survive, and bacteria have evolved to use many of the chemicals in oil as energy sources. The bacteria must have gone wild; they ate enormous amounts of oil as it migrated into these rocks.

The stuff left over is, well, leftover waste. It was the stuff too complicated or too difficult for the bacteria to consume. Oil is made up of many chemicals, some of them easy to use, some not. The not-so-easy-to-consume chemicals were left in the rocks, which built up into thick piles of sticky sludge. Furthermore, that sludge is mixed in with the sandy estuary rocks; the sludge and sand stick together like road-building materials. When these rocks are exposed at the surface, they can be sticky, sometimes seeping thick viscous carbon-rich oozes, but they’re really solid rock.

That’s the stuff being mined as tar sands and converted to gasoline in Canada. The process is like taking a freshly-paved, blacktop road, grinding up the material, and extracting oil from it. Many people in the Midwestern U.S. right now are running their automobiles using gasoline created from the leftover products of whatever bacteria didn’t eat in these oil reservoirs, but mankind has figured out a way to process industrially.


References: Zhou et al., (2008) Biodegradation and origin of oil sands in the Western Canada sedimentary basin
http://www.springerlink.com/index/P4277621627L47K7.pdf

Musial et al., (2011), Subsurface and outcrop characterization of large tidally influenced point bars of the Cretaceous McMurray Formation (Alberta, Canada)
http://www.sciencedirect.com/science/article/pii/S0037073811001722

Geologic features of the Athabasca oil sands
http://www.ramp-alberta.org/river/geography/geological+prehistory/mesozoic.aspx

Image credit: UT Austin Bureau of Economic Geology
http://www.beg.utexas.edu/indassoc/dm2/qcl_news_2010.htm

Friday, March 15, 2013

NATURAL DISASTER: TOHUKU EARTHQUAKE AND TSUNAMI


Today, March 11 marks the two year anniversary of the deadly Tohuku earthquake and tsunami. The earthquake was the strongest in Japanese recorded history, registering 9.0 on the Richter scale, and one of the 5 strongest recorded in the world since 1900. The epicenter was located about 70 km (43 mi) off the coast of the Oshika Peninsula at a depth of 32 km (20 mi). Although the death toll and damage from the earthquake was severe, the greatest destruction was caused by the deadly tsunami that followed. The tsunami traveled inland up to 10 km (6 mi) in the Sendai area and reached an incredible height of 37.88 m (124 ft) in Miyako. The estimated death toll was 15,853, with at least 6.023 injuries and 3,282 missing. The infrastructure damage was severe, as well with 129,225 buildings collapsed, 254,204 half-collapsed and 691,776 partially damaged. Of great concern for weeks after the event was the damage to the Fukushima Daiichi nuclear reactor, which suffered a level 7 meltdown.

The earthquake was classified as a megathrust quake and occurred along a subduction zone, an area where the Pacific plate is sinking below the North America plate in the Japan Trench. Studies after the event indicate the seabed between the earthquake epicenter and the Japan Trench moved approximately 50 m (164 ft) east-southeast and rose about 7 m (23 ft). Many seismologists were surprised by the strength of the earthquake, as past modeling studies indicated subduction zone quakes in that are would not exceed magnitude 8.4. However, models were generated using data from short historical records. New work is being done to revisit models and include paleoseismic records, although even those events are limited. Several other subduction zone areas in the world may need to be studied and revised as potential 9.0 magnitude zones.

The tsunami generated by the earthquake was far more destructive than the initial quake. A tsunami occurs when the seafloor abruptly deforms, causing a vertical displacement in the water. A series of long-wavelength waves, or wave train, is formed as the water attempts to regain equilibrium. Although the government of Japan issued tsunami warnings after the earthquake, the loss of life was severe due to the unprecedented height of the waves. The tsunami waves inundated approximately 561 km2 (217 mi2) at heights over 9m (29 ft) in many coastal cities.


Photo: Wave crashing over a street in Miyako City, Japan, courtesy of Mainichi Shimbun, Reuters

References and additional information:

http://mceer.buffalo.edu/infoservice/disasters/Honshu-Japan-Earthquake-Tsunami-2011.asp
http://www.sciencedaily.com/releases/2013/01/130123133901.htm
http://earthquake.usgs.gov/earthquakes/eqinthenews/2011/usc0001xgp/


Additional posts from The Earth Story:

http://tinyurl/afrevrb
http://tinyurl/atexxzw




View from Angel's Landing, Zion National Park (Utah)


A strenuous, 8 kilometer hike will take you to this stunning view overlooking Zion Canyon atop Angel's Landing in Zion National Park. Towering canyon cliffs stand around the valley, as the Virgin River winds itself through the canyon floor.

The genesis of these cliffs lies in the deposition of sand 240 million years ago. Zion was originally adesert basin, but as surrounding mountains underwent natural erosion, sand was produced. Rivers around the basin transported the sediment, depositing it into layers. Sedimentation occurred, and sand eventually overtook the water-covered basin, turning it into a basin of not water, but sand. Stratum upon stratum of sand layered atop one another over millions of years.

This resultant sand began to undergo lithification and compaction into rock via the filtration of mineral-rich water. Aqueous iron oxide, calcium carbonate, silica, and other minerals helped to turn sediment into sandstone, limestone, and other rocks. Uplift caused the rock to rise further out of the ground, raising these large piles to an elevation of 3000 meters, and still rising today.

Then how are these canyons and steep cliffs formed? Erosion! The Virgin River in Zion is the chief waterway responsible for this erosion. 90% of erosion comes from flash flooding, rather than normal water flow. This erosion carved the preliminary, historic canyon walls of Zion, continuously widening it.

The wide canyon and steep cliffs you see in this image are results of this historic process - sedimentation, lithification, uplift, and erosion. Today, over 4,500 metric tons of rock are stripped of the canyon walls by the Virgin River every day! In combination with the more significant flash flooding, the depth of the Zion Canyon is expected to decrease by 183m (600 feet) in a million years, or 0.18 millimeters per year.

Gorgeous!


Did lightning strikes feed early life?


Since the 1953 Miller-Urey experiment which used simulated lightning in a replica of the early atmosphere to create amino acids, speculation on the role of lightning in generating early life has continued. Research by scientists at the University of Arizona now suggests a new mechanism by which lightning may have helped life on its way.

The research involved multi-instrument analysis of rocks called fulgurites, named after the Latin for thunderbolt (and also known as lightning glass). These form when lightning strikes moist silica rich soil or rock, melting and vaporising it as the electrical energy dissipates into the earth. The melt cools swiftly to a glass, similar to that of impact tektites such as Moldavite, and often takes the shape of a hollow tube as the vapour component escapes. Fulgurites resemble roots or branching corals, whose shapes reveal the pattern of electrical dissipation in the earth as the current follows the path of least resistance through the particular material. They are a good illustration of the Chinese concept of Li (literally the markings in jade), which is incorporated into one of their words for science and translates as patterns of organic energy. Their colour depends on the chemical makeup of the rock and their size on the depth of penetration of the strike, which also gives a measure of its energy. They are usually quite small (< 1 metre) but a record 4.9 metre specimen was once found in Florida. They are collectable and can be quite expensive.

The analysis revealed that lightning may have helped enrich the early earth in vital nutrients in a form early life could assimilate. It was already known as one of the few abiotic means of fixing nitrogen (which is why we use agricultural fertilisers), but this research demonstrates its role in providing phosphorous in the reduced form used by early life. Phosphorous is a vital constituent of RNA/DNA and cell membranes, and was once referred to by Isaac Asimov as 'life's bottleneck' as it constitutes 1% of organisms while only being present in 0.1% of the world's minerals. It is usually the limiting nutrient in an ecosystem as its hard to dissolve and moves slowly through the rock cycle.

Nowadays, phosphorous is relatively plentiful, mostly as fully oxidised orthophosphate. In the Achaean and early Proterozoic, before oxygen entered the atmosphere, reduced phosphorous was a larger percentage of the available stock, and early life evolved a different chemical pathway for incorporating it to that of modern life. Modern phosphate comes from the weathering of rock in our current oxidising atmosphere, but on early Earth the geochemical sources must have been different.

Lightning is one of the few natural phenomena powerful enough to reduce phosphorous, electricity providing the energy, while the organic matter in the soil strips off the oxygen, acting as the reducing agent (though other reduced elements more reactive than Phosphorous could have done it on early Earth). Analysis of modern fulgurites showed elevated amounts of reduced phosphorous in proportion to their contents of organic matter. Since the element is rare today in its reduced forms, biologists are puzzled why many micro-organisms retain the enzymes to process it, and the genetic evidence suggests that this is an ancient biochemical pathway. They believe it was more common on the primordial Earth, and had long posited the existence of a geological source of reduced phosphorous, which the Earth sciences have now found for them.

The real joy lies in the feeling that as the work of geoscience progresses each year, each brick builds into an awareness of the whole Earth system. Terra doen't divide itself into pieces in the way that those of us who study it do. As we get to know it as an undivided whole, our love and respect for our wonderful world grows with the profundity of our understanding.


Fulgurite image credit: Stan Celestian and Earth Science Picture of the Day: http://epod.usra.edu/

http://blogs.nasa.gov/cm/blog/whatonearth/posts/post_1290194194320.html

http://www.scientificamerican.com/article.cfm?id=spark-for-life-lightning

Fulgurite and phosphite paper:http://www.lpi.usra.edu/meetings/abscicon2010/pdf/5261.pdf

http://www.gemstonesadvisor.com/fulgurite/



Tao Rusyr – An island within an island


The Kuril Islands are part of one of the most volcanically active areas in the world, activated by the subduction of the Pacific Plate under the Eurasian Plate along a 200 km long deep-sea trench. The remarkable Onekotan Island contains a 7.5 km wide caldera, Tao-Rusyr which formed during a VEI (Volcanic Explosivity Index) 6 eruption around 5500 Before Christ. (For an overview of the VEI, see http://volcanoes.usgs.gov/images/pglossary/vei.php) A caldera forms when the magma chamber under a volcano empties and collapses creating a cauldron-like structure. Caldera’s often fill with water, in case of Tao-Rusyr, Kal’tsevoe Lake.

Not long after the big eruption the magma chamber of Tao-Rusyr filled up again. However, the magma could not move through the solid rock of the caldera floor and thus a new volcanic cone, an island within an island, Krenitzyn Peak formed. At 1325 m high the volcanic cone towers high above Onekotan Island. Also, it has a 350 meter wide and 100 meter deep crater. In 1952, a week after a 9.0 earthquake occurred along the subduction zone a VEI 3 eruption occurred on the east flank of Krenitzyn peak creating a small lava dome.

On the northern end of Onekotan island three much older overlapping calderas make up Nemo Peak. One caldera was created 25,000 years ago, the other two 9500 years ago and more recently. Here, a central cone is surrounded by the crescent shaped Chernoe Lake.


Image: NASA Earth Observatory. The image shows Tao-Rusyr with Krenitzyn Peak on the right and Nemo Peak on the left.

KURILE ISLANDS, ALEXANDER BELOUSOV AND MARINA BELOUSOVA. Institute of Volcanology and Seismology, Petropavlovsk, Russia. THOMAS P. MILLER. U.S. Geological Survey. 2009

http://www.volcano.si.edu/world/volcano.cfm?vnum=0900-31%3D
http://www.volcano.si.edu/world/volcano.cfm?vnum=0900-32%3D
http://volcanoes.usgs.gov/images/pglossary/caldera.php
http://earthobservatory.nasa.gov/IOTD/view.php?id=40891



The rarest lava on Earth


Nearly all volcanoes on Earth erupt silicate lava--that is, lava which primarily forms minerals containing silicon and oxygen. Some rare exceptions to this can be seen in carbonatites, igneous rocks that consist primarily of carbonate minerals--usually dominated by calcite or dolomite, and often with silicate minerals mixed in. Only one volcano erupts carbonatite lava today: Ol Doinyo Lengai, a rift volcano in Tanzania (see crater in picture). But Ol Doinyo Lengai's lavas are unique even for carbonatites: while most carbonatites in the geologic record are dominated by calcite or dolomite, Ol Doinyo Lengai's lavas are extremely rich in sodium and potassium, and often contain less than 0.5% silica. As it cools below the surface, the magma mainly forms two rare sodium-calcium-potassium carbonate minerals, nyerereite and gregoryite. The lava is black and usually flows very easily, and may look like a mud flow. At the surface, however, the minerals are quickly weathered, turning the rock from black to almost white.

Geologists think that natrocarbonatite magma forms by separating from a body of silicate magma, similar to how a mixture of oil and water will separate. Ol Doinyo Lengai's rock record may suggest that this occurred fairly recently within the mountain: most of the mountain was built by eruptions of sodium- and potassium-rich silicate lava, with natrocarbonatite eruptions starting only recently in its history. Even today, eruptions alternate between nearly pure natrocarbonatite and relatively silica-rich episodes, and in a few eruptions, small spheroids of silicate material were carried along with the natrocarbonatite.


Image: Crater of Ol Doinyo Lengai, Tanzania, January 2011. Photo by Albert Backer, http://en.wikipedia.org/wiki/File:Crater_of_Ol_Doinyo_Lengai_(Jan_2011).jpg
References:
http://hvo.wr.usgs.gov/volcanowatch/archive/2003/03_04_17.html
http://blogs.stlawu.edu/lengai/what-is-carbonatite/
http://www.sciencedirect.com/science/article/pii/S0024493712002149




The Theory of Relativity


“Anyone who has never made a mistake has never tried anything new.” –Albert Einstein

On March 14, 1879 Albert Einstein was born into a middle class Jewish family. He had speech difficulties did not speak until the age of three and was interested in physics at an early age. An encounter with a compass at the age of five and trying to figure out the invisible forces acting upon the needle helped to spark his interest. He attended school at Luitpold Gymnasium in Munich where he excelled at his studies.

In 1889 the Einstein family invited polish medical student Max Talmud over for weekly dinners and he soon became Einstein’s “tutor” and introduced him to higher mathematics as well as philosophy. He shared a children’s science book with Albert that really peaked his interested and would ultimately lead to his first scientific paper at the age of sixteen – “Investigation of the State of Aether in Magnetic Fields”. In the book, the author goes for a ride alongside electricity travelling down a telegraph wire. After reading this, Einstein started racking his brain as to what a beam of light looked like. If light were a wave then the beam should appear stationary, but since it was moving this could not be true. Also he began to question the speed of the light relative to a stationary observer. These questions were in the forefront of Einstein’s mind for the next ten years.

Albert’s father ran his own electrical company and when it failed to secure a huge electrical contract to power Munich, the family was forced to move to Milan, Italy. Albert was left behind to live in a boarding house and finish school. He was alone and miserable, and hoping to avoid entering the military, Albert obtained a doctor’s note and left to join his family in Italy. His parents were understanding but also concerned what sort of issues he may face as a dropout and draft dodger.

He then applied to the Swiss Federal Polytechnic School in Zurich; he lacked the equivalent of a high school diploma but scored exceptionally well on the math and physics portion of the entrance exam. He was admitted on the condition he had to complete his schooling first. In 1896 at the age of seventeen, Einstein graduated, renounced his German citizenship and enrolled in the Zurich school. It was at this school where he met his future wife, Mileva Maric. She was Serbian and this coupled with her Eastern Orthodox background made Einstein’s parent disapprove. His father ended up giving the couple his blessing before he died. The couple married in 1903 and had two sons shortly after.

Einstein’s father’s business went bankrupt and he was forced to find any job he could hold onto in hopes of being able to provide for his future bride. In 1902, a friend of his father’s tipped him off to an opening at the Swiss patent office. Einstein jumped on this opportunity as evaluated patent applications for various electromagnetic devices. He quickly mastered his job at the patent office, freeing up his mind to contemplate more complex issues like the transmission of electrical signals and electromagnetic synchronization.

He studied Maxwell’s electromagnetic theories on the nature of light and uncovered a previously unknown fact – the speed of light was constant. This was a violation of the Newtonian theory and ultimately led Einstein to formulate his theory of relativity.
The year 1905 is often thought of as Einstein’s miracle year and it was during this time he submitted a paper for his doctorate, along with publishing four papers in the Annalen der Physik – one on the photo electric effect, Brownian motion, special relativity and one on the equivalence of matter and energy. These publications altered the course of modern physics and put him on the academic world’s radar.

In his paper on matter and energy, he introduced the equation we are all familiar with today – E=Mc2. This equation suggested tiny particles of matter could be converted into vast amounts of energy. His papers received little attention until they caught Max Planck’s eye. Planck’s comments and experiments confirmed Einstein’s theories and expedited his rise to the top in the academic world – leading to job offers at very prestigious universities.

His rise to fame played a toll on his personal life. His marriage to Mileva fell apart and the couple divorced in 1919; as a divorce settlement he agreed to pay Mileva money he for any potential Nobel Prize he may win.

He completed what he considered to be his masterpiece, his theory of general relativity, in November 1915. He was convinced of its mathematical beauty and how accurately it predicted the Mercury’s perihelion (point of orbit closest to the Sun). General relativity also predicted a measurable deflection of light around the Sun when a planet was near in its orbit. This prediction was first confirmed by British astronomer Sir Arthur Eddington while observing a solar eclipse in 1919.

A few years later in 1921, Albert Einstein received the Nobel Prize for physics – not for his theory of general relativity but for his findings on the photoelectric effect. He single-handedly launched the new science of cosmology. He used his cosmological constant combined with the theory of relativity to show that our universe was static. Soon after he realized this was incorrect, that the universe was actually expanding and called it his “biggest blunder”. It was realized later that his cosmological constant and theory of relativity was actually correct and the universe was expanding which Edwin Hubble confirmed.

Big changes were happening in Germany; as Einstein was rising to the top of the academic world, Hitler was rising to power in Germany. He had his own team of physicists working to dispel Einstein and his “Jewish physics”. At the time Jewish people were not allowed to hold any kind of official position and Einstein was actually on Hitler’s “hit list”. In 1932 Einstein said goodbye to Germany forever and moved to Princeton, NJ where he took a position at the Institute for Advanced Study. He spent the rest of his career here working to develop a unified field theory.

Several other European scientists fled Europe at this time and moved to the United States. It was rumored that Nazi Germany was trying to develop nuclear weapons, and a few of these scientists tried to warn the US government but were ignored. Finally in 1939, Einstein and another scientist, Leo Szilard, wrote a letter to then President Franklin D. Roosevelt to warn him about the proposed atomic weapon. They were able to grab his attention and Roosevelt met with Einstein and soon after the Manhattan Project was born.

Einstein was granted permanent residency in the US in 1935 but did not become a citizen until 1940. The Manhattan Project was moving forward and many of Einstein’s colleagues were asked to assist in creating the first atomic bomb, but it’s rumored J. Edgar Hoover and the FBI did not trust Einstein’s affiliation with peace organizations. While his colleagues worked on the atomic bomb, Einstein helped the Navy with weapon system design.

In 1945, Einstein heard the news that the US dropped the atomic bomb on Japan. Along with his friend Leo Szilard, they campaigned for the US to supply the United Nations with the nuclear weapons to be used as a deterrent only. Once the war was over, Einstein continued his work on relativity focusing on time travel, black holes, and the creation of the universe. The development of the atom bomb had resulted in huge discoveries in quantum theory.

In the latter part of his life, Einstein spent the majority of his time working on his unified field theory. Einstein was working on a speech to commemorate Israel’s 17th anniversary when we suffered and abdominal aortic aneurysm. On April 18, 1955 Einstein died in the hospital after refusing surgery. He believed he had lived his life and was ready to accept his fate. After his death, Thomas Stoltz Harvey removed and preserved Einstein’s brain without permission. Samples were taken and slides were made of his brain for future analysis. Recently Harvey’s slides have been digitized and you can see an example of one herehttp://bit.ly/Yds8fv . This slide is of the occipital lobe of Einstein’s brain.


Source:
http://www.nobelprize.org/nobel_prizes/physics/laureates/1921/einstein-bio.html
http://www.biography.com/people/albert-einstein
http://www.alberteinstein.info/
http://einstein.biz/

Image Credit:
Einstein.biz/National Museum of Health Chicago

Tuesday, March 12, 2013

OMG bees !!


An immense observation hive in the Netherlands:
Imagine having this in your house. I think it is quite beautiful and probably makes your house smell like honey. Would you like to have an observational hive in your house?

visit our website for more Amazing Stuff at -http://adf.ly/KdV1V



Wednesday, March 6, 2013

Dark Matter in 3D


Abell 383 is a galaxy cluster located approximately 2.3 billion light-years away. Galaxy clusters are the largest celestial objects gravitationally bound; they play a key role in understanding dark matter. Astronomers recently used data from Chandra X-ray Observatory to map the cluster’s dark matter. After careful data analysis they were able to determine where the dark matter was located and how it is distributed.

The dark matter was observed through gravitational effects and the data shows there is six times as much dark matter as normal matter. Astronomers gathered the data and were able to generate 3-D pictures of the elusive dark matter. They observed the dark matter was stretched out to form a gigantic American “football” and that the football’s point is lines up close to the line of sight.

Two teams of scientists at two different universities studied Abell 383 and came up with similar as well as very different observations. After combining x-ray observations of “normal matter” with optical data derived from gravitational lensing, they observed arc-like appearance for some of the galaxies. You can see the “arc” in the image. The vast purple area is x-ray data from Chandra highlighting hot gas – the dominate type of matter in the cluster.

Team Newman (and yes I said that in Jerry Seinfeld’s voice), headed up by Andrew Newman (CalTech) and Tommaso Treu (UCSB) combined Hubble lensing data with Japanese telescope Subaru and adding Keck observations to measure star velocities in cluster center. This allowed for a direct estimate of dark matter. The data showed the dark matter was not as concentrated in the cluster’s center as predicted by the standard cold dark matter model.

Team Morandi lead by Andrea Morandi (Tel Aviv University) and Marceau Limosin (Université de Provence/University of Copenhagen) determined the dark matter concentration to be higher towards the cluster center and the observation are in line with most theoretical models. Data from the Hubble space telescope was also analyzed by this team.

So we have two teams and two different results – how does this happen? One key reason is Team Newman used velocity data in the central galaxy and was able to estimate the dark matter density close to the cluster’s center – as close as 6,500 light-years away from center. Without the velocity data, Team Morandi was only able to estimate density as close as 80,000 light-years. Team Morandi were able to predict the dark matter “football” orientation. Further studies are needed to clear up the discrepancies between these two teams. It may be a while before we find out which is correct – Team Newman or Team Morandi.

If Team Newman’s results are validated and there is a lack of dark matter in Abell 383’s center, then we need a better understanding of how normal matter conducts itself in galactic centers and may demonstrate how dark matter particles interact.


Source:
http://phys.org/news/2013-02-abell-full-picture-elusive-subject.html

Image Credit:
NASA/CXC/Caltech/ESO/VLT/SDSS

MONTH IN THE UNIVERSE - FEBRUARY 2013


Can't read the image? Click here: http://i.imgur.com/AsGCer1.jpg

Missed Part One? Click here: http://imgur.com/miCJFcb.jpg

Though February is the shortest month of the year, it wasn't short on discoveries and events. The Universe Team invites you to take a look back with us.

1. LANDSAT 8 LAUNCH - Landsat Data Continuity Mission spacecraft launched February 11th. Read more:http://on.fb.me/Wrgqmf (Image credit: NASA/VAFB)

2. ISS BLACKOUT - The day before a planned Google+ Hangout, NASA completely lost contact with the International Space Station. Read more: http://on.fb.me/15tPa74 (Image credit: NASA)

3. SMARTPHONE LAUNCHED INTO SPACE - British spacecraft STRaND-1 carried a Google Nexus One smartphone into space. Read more: http://on.fb.me/XGE5MO (Image credit: Surrey Satellite Technology Ltd.)

4. INDIA'S 101ST SPACE MISSION - India's Polar Satellite Launch Vehicle carried the Indo-French oceanographic study satellite 'SARAL' from the Satish Dhawan Space Centre. Read more: http://on.fb.me/Y97vAo (Image credit: Associated Press)

5. PLANS ANNOUNCED FOR MANNED MARS FLYBY - Dennis Tito's nonprofit Inspiration Mars Foundation announces plans to send a manned mission to do a flyby of Mars by January 2018. Read more: http://on.fb.me/XSqdgs (Image credit : Inspiration Mars Foundation)

6. CURIOSITY DRILLS FIRST ROCK SAMPLE - The Mars rover sent back images confirming that it had drilled the first ever rock sample taken from the interior of another planet. Read more: http://on.fb.me/105NHVp (Image credit: NASA/JPL-Caltech/MSSS)

7. ASTRONOMY SOFTWARE HELPS FIGHT CANCER - Software originally developed for spotting exoplanets found a new use in tumor analysis. Read more: http://on.fb.me/Y9e45Y (Image credit: Medgadget.com)

8. R.I.P. DAVID MCKAY, MARS PROGRAM FOUNDER - Dr. David McKay, astrobiologist, passed away at the age of 77 on February 20th. His research was instrumental in initiating the Mars Exploration Program as well as the foundation of the NASA Astrobiology Institute. Read more: http://on.fb.me/Y9erxo (Image credit:http://extremethinkover.files.wordpress.com/2010/02/david_s_mckay1-astrobiologist.jpg)

9. BAUMGARTNER RECORD CONFIRMED - The World Air Sports Federation confirmed that Felix Baumgartner's 38.969.4 meter jump did, in fact, break three records. Read more: http://on.fb.me/13CF0Tx (Image credit: Red Bull Stratos)





Powered By Blogger