Ch+13

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Can Coal Be Earth Friendly? media type="custom" key="13163880"

Mir Mine - The largest diamond mine in the world

At 525 meters deep, the Mir mine in Eastern Siberia is the fourth deepest open mine pit and the second largest excavated area in the world. In 1955 it was the first kimberlite pipe to be discovered in Russia. At the time the Soviet Union required big amounts of industrial diamonds to rebuild the enormous country, especially in mechanical machinery . Mining conditions at Mir were extremely harsh. During the seven month winter temperatures were so low that oil and rubber tires of vehicles froze. In addition, the mine had to be covered to prevent the heavy machinery from freezing. Summer did not make conditions much better since the permafrost would transform into stubborn mud.

At its height the mine produced around 2 million carats of diamonds a year. However, from the 1970s onward, the Mir mine started producing smaller amounts of diamonds until in 2004 the mine was closed.

In 2010 plans came out of a Russian construction company hoping to build a domed city in the abandoned mine powered by solar energy. It could house up to 100,000 people.

(for more info see http://www.wired.co.uk/news/archive/2010-11/17/russia-domed-city-siberia )

-BO

Image: Filip Singer

References:  http://www.abazias.com/diamondblog/diamond-industry/a-brief-history-of-the-worlds-largest-open-pit-diamond-mine  http://www.atlasobscura.com/places/mirny-diamond-mine

Sobolev & Logvinova et al. 2004. Mineral inclusions in microdiamonds and macrodiamonds from kimberlites of Yakutia: a comparative study.



The Danish seismologist Inge Lehmann (1888-1993) is best known for discovering Earth's inner core, though this was only the most important single discovery of a long and productive career. She was born in Copenhagen and educated at a coeducational school where boys and girls were treated identically and where, she said, "No difference between the intellect of boys and girls was recognized, a fact that brought some disappointments later in life when I had to recognize that this was not the general attitude." She studied mathematics at university and did actuarial work before being introduced to seismology around 1925-26, when she became the assistant to a director of a geodetic institute and was tasked with installing seismographs in a new station in Copenhagen. Upon learning that seismographs could be used to reveal the inner structure of the Earth, Lehmann began studying seismology on her own and soon started her own research, and in 1928 earned a degree in geodesy and a position as chief of the Royal Danish Geodetic Institute's seismology department. She worked on the problem of determining the travel times of seismic waves over distances, a task that was difficult early in her career due in part to the poor distribution of seismic stations in Europe; she preferred to analyze seismograms from different stations herself to make interpretations more consistent, as different seismologists might read different wave arrivals, making correlation more difficult. Through careful analysis of earthquake records, she argued in a 1936 paper that certain anomalous seismic waves had been reflected off a discontinuity in the core; this is now known to be the boundary between the liquid outer core and the solid inner core.

 Later in her career, especially in the 1950s, Lehmann studied the propagation of different kinds of surface and body waves, some of which had been difficult to resolve in seismic records. In the early 1960s, a number of countries began to improve and standardize their seismographs in large part for surveillance of underground nuclear testing. This allowed seismic records, which before were generally made by non-standardized equipment, to be compared far more easily across the world, and drove much of her last decade of research, which largely focused on the structure of the upper mantle and the analysis of seismic waves from nuclear explosions.

 - Robin F.

 Image: Photo of Inge Lehmann, date unknown, by B.A. Bolt. Image source: http://www.amnh.org/education/resources/rfl/web/essaybooks/earth/p_lehmann.html  Further reading: <span class="text_exposed_show"> A biographical essay by a fellow seismologist: http://www.physics.ucla.edu/~cwp/articles/bolt.html <span class="text_exposed_show"> Lehmann's recollections of her early seismology career: @http://www.geus.dk/departments/geophysics/seismology/seismo_lehmann_art-dk.htm

<span class="text_exposed_show"> <span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">GEODES

<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">For those of you who have a geode sitting on your desk that your Aunt Margaret gave you for Christmas three years ago, pick it up now and take a closer look at it.

<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">There are many kinds of geodes filled with many kinds of minerals but one thing they all have in common, that which defines them as geodes is – that they all originated because of an empty hollow space within the earth.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">Most geodes are quite spherical in shape (but not all), and those that contain empty cores are called “duds” (I have no idea why, since I like them), those with crystal lined cores are simply “geodes,” and those that are solid are called nodules (a misnomer since not all nodules are geodes, and in the scientific sense, a nodule precipitates from an inner core outward, so go figure).

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">In lava beds, the hollows that preceded geode formation are attributed to gas bubbles whose shapes are preserved when the lava hardened. The tremendous amethyst-filled giant geodes from Brazil are hosted by lava tubes and gaseous-filled cavities.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">In sediments, the problem of hollow spaces is more complex. In some cases, vegetation, burrows or animal fragments (including bones and shells) are buried by sediments, then “leached out” during rock formation, leaving behind an open hollow. Other sediments that provide “hollows” for geode formation are mixes of silicate and clay mineral sediments with limey sediments: when lithification occurs, silica and lime tend to segregate (“unmix”). The result can be limestone full of round chert (silica) nodules, or sandstone-claystones with limestone concretions. When these concretions react with ground water, they can dissolve, leaving behind a generally spherical void where the concretions used to be.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">Once there is a hollow space present, the waters of the earth do the rest of the work for us: over tens of thousands of years, groundwaters and/or hydrothermal waters wend their ways through the hosting rocks, filling the hollows, and slowly depositing minerals from various elements carried by these waters. As for cave formations, waters containing calcium can deposit rims, linings, and even precipitate as superb crystals of calcite or dolomite. Waters leaching through silicate rocks deposit dissolved silica, reforming as a variety of minerals, most gorgeous. When hydrothermal fluids are involved, sulfide-based minerals can precipitate within the hollows.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">Minerals and types of crystals that can fill geodes are as varied as are the way that geodes form: the image shown with this post is a geode slice that contains silica minerals of at least five different varieties: red jasper around its rim, chalcedony (a mix of microcrystalline quartz and moganite with some iron impurities causing the mustard hue), rock crystal (clear quartz crystals), opal (white milky-looking bands), and a tinge of pink quartz in the middle. In other geodes, amethyst (quartz that has impurities of iron and transition metals in its atomic structure) is treasured. A lovely geode from Ethiopia is filled with twinkling rainbow-colored opal ( @http://tinyurl.com/csv4qhh ). Other minerals a delight to find when one saws open a geode to explore its mysterious interior include: selenite (a calcium sulfate that can make lovely bladed crystals), pyrite and chalcopyrite, malachite, galena, sulfur… the list is as endless are there are geodes.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">Among geodes you might see for sale on-line or in a mineral store are some that possess amazing colors – far too amazing to be real, in fact. Indeed, these are stained by a fairly simple process of boiling them in fabric dye. Why someone would prefer a geode the color of Aunt Margaret’s bathroom rather than its original “gift from the earth” color is beyond me.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">Annie R

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">Image: This is a scanned image of a slice of geode that sits on my desk, ready to hold a hot cup of coffee, was collected this in a lava field in Arizona.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">Some refs: <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;"> @http://www.desertusa.com/magjan98/jan_pap/du_rock_geode.html <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;"> @http://www.isgs.illinois.edu/maps-data-pub/publications/geobits/geobit3.shtml

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 11.199999809265137px;">

<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">ATHABASCA TAR SANDS

<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">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 reaso <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">ns.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">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 exactly it is, since that doesn’t get discussed very often. If nothing else, it probably will lead to some lively comments!

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">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.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">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.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">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.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">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.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">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.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">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.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">-JBB

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">References: Zhou et al., (2008) Biodegradation and origin of oil sands in the Western Canada sedimentary basin

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;"> @http://www.springerlink.com/index/P4277621627L47K7.pdf

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">Musial et al., (2011), Subsurface and outcrop characterization of large tidally influenced point bars of the Cretaceous McMurray Formation (Alberta, Canada)

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;"> @http://www.sciencedirect.com/science/article/pii/S0037073811001722

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">Geologic features of the Athabasca oil sands

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;"> @http://www.ramp-alberta.org/river/geography/geological+prehistory/mesozoic.aspx

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">Image credit: UT Austin Bureau of Economic Geology

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;"> @http://www.beg.utexas.edu/indassoc/dm2/qcl_news_2010.htm

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">

<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">For your consideration…the Alabama Hills.

<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Ok, I’ll be honest …I’m secretly hoping someone screams “Nerd!” at me in the comments, because in this post I’m reveling in it. I’ve already got my tickets for Iron Man 3 this weekend, and considering that Disney is spending tens of millions of dollars marketing that film, I might as well try to tag along. Either I’ll be stealing attention from their mark <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">eting, or helping it, or maybe both. So, for this post (and my next one), I’m delving into geology that appeared in the first Iron Man film.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">This image comes from the state of California, just outside of the town of Lone Pine, a place known as the Alabama Hills. In the background, you can see the Sierra Nevada mountain range, with Mount Whitney, the highest peak in the continental United States, in the distance almost at the center of the frame.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">In California, the main mountain range, the Sierra Nevada, runs north-south through the state. On the west side, the Sierras gradually lose elevation and merge into sedimentary basins in the Central Valley, but on the east side, they stop abruptly.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">The Sierras are cut on their eastern side by a series of normal faults that have dropped the rocks down and created a deep, sediment-filled basin known as Owens valley. You can see the trace of one of those faults in this image; it basically marks the place where the mountains go from incredibly steep to very flat.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">The Alabama Hills sit right in the middle of Owens Valley. They’re made of granite that is very similar to the rocks of the Sierra Nevada, but there are about 3 kilometers of valley floor between them and the Sierras. The Alabama Hills are a block of the Sierras basically trapped in the middle of Owens valley.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">These hills are pieces of Sierran granite, but because they are bounded by faults, they didn’t drop down as far as the rest of the valley. The faults around the hills still move, and in fact there was a magnitude 7.4 earthquake along the east side of the Alabama Hills in 1872.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">They sit in an incredibly picturesque area. There isn’t a lot of rain, so the hills don’t erode rapidly, but since they’re not big they’re easy to climb on or drive around, and they have the gorgeous Sierra Nevada as a backdrop. These hills are such a great location that they show up throughout Hollywood history. The other name for the portion of land right around the Alabama Hills sums this up pretty well; Movie Flat. If you look in the background of any number of “western” movies, there’s this remarkable habit of Mount Whitney showing up. Django Unchained, Gladiator, Tremors, How the West was Won; the list of films shot here seems endless. Captain Kirk was even buried here.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">The Alabama Hills also sit in the rain shadow of the Sierras; they don’t receive much precipitation, making the area great for filming desert scenes. The weathering granite helps as well, it weathers to grus; broken up fragments of the grains in the granite that don’t host much vegetation and give a good impression of a desert when they’re on camera.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">That brings me back to Iron Man. In the 2008 Iron Man film, the Alabama Hills played a key role, standing in for Afghanistan. This spot is where Tony Stark demonstrates the Jericho Missile. In fact, they test the missile on the Sierras; literally on the slopes just south of Mount Whitney. The scene where Stark is attacked and captured by militants, leading to the development of his miniaturized arc reactor, was also filmed right here, in the Alabama Hills. So effectively, the entire Iron Man film series (and the other Avengers movies) got their start right here, in the shadows of Mount Whitney.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">So, to paraphrase the movie…ladies and gentlemen, for your consideration…the Alabama Hills.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">-JBB

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Photo credit: Me! No rights reserved.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">1872 Lone Pine Earthquake: <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> http://en.wikipedia.org/wiki/1872_Lone_Pine_earthquake

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Alabama Hills on Tripadvisor: <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> http://www.tripadvisor.com/Attraction_Review-g32646-d117177-Reviews-Alabama_Hills-Lone_Pine_California.html

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Alabama Hills from the BLM: <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> http://www.blm.gov/ca/st/en/fo/bishop/scenic_byways/alabamas.html

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Lone Pine Film Database (39 pages!): <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> @http://www.lonepinefilmhistorymuseum.org/index.php?option=com_joodb&view=catalog&Itemid=31

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">And why not, the video clip: <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> @http://www.corporate-aliens.com/quotes/getquote.php?Tony-Stark&quoteid=462



<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">It turns out the core of the Earth is closer to about 6000 degrees Celsius, about 1000 degrees hotter than previously estimated. This is good, because the difference between the core and the mantle needs to be at least 1500 degrees to create a magnetic field. To read more about the new estimate and why the old estimate was wrong, go to:

<span style="background-color: #ffffff; color: #3b5998; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; text-decoration: none;">@http://www.sciencedaily.com/releases/2013/04/130425142355.htm



<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">About 23 million years ago, when the Tibetan Plateau began to rise, a river was born.

<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">The Yangtze river runs through China, from the Tibetan Plateau to the East China sea. It is the world's third longest river (6300 kilometers or about 4000 miles) and scientists have long debated its age. Now, thanks to researchers from Nanjing Normal University in China, the age of the river was determined using <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> rocks found in the Jianghan Basin (below the Three Gorges Dam).

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Picture courtesy of:

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> @http://www.china-tour.cn/China-Pictures/Yangtze_River_Three_Gorges_1.htm

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Sources:

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> @http://www.sciencenews.org/view/generic/id/349900/description/News_in_Brief_Yangtzes_age_revealed

<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Monument Rocks, Kansas

<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Some of the flattest land in North America is in the Great Plains, located in center of the United States. In Kansas, a state known particularly for its open green prairie, limestone giants, known as the Monument Rocks, defy this trend and rise up out of the flattened landscape. Standing as tall as 21 m (≈70 ft) the ancient limestone formations seem to resist the power of g <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">ravity and rise up to the sky. The formations have also earned the more local name of the Chalk Pyramids of Kansas.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">The rocks are some of the last bits of an ancient sea floor that extended from the Gulf of Mexico all the way up into Canada. Over millions of years, the sea dried up and erosion took its toll on the limestone seabed. Much of the limestone has been completely eroded away, leaving the Monument Rocks standing alone in a deserted and dried up sea. The rocks’ ties to the ocean are in fact still present to this day in the form of fossilized plants, animals, and an abundance of seashells that are contained within the limestone. Visitors are asked to refrain from touching or taking any sea shells, as their presence alone offers a look into North America’s geology some 80 million years ago.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Much like a sunken ship does in the middle of an ocean, the rocks attract wildlife and make home to a significant number of birds including the world’s smallest falcon and rock doves (common pigeons) in one of their original natural habitats. Here, the rock doves ‘jump’ from rock to rocks, similar to how they do from building to building in modern day cities.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Today, the Monument Rocks/Chalk Pyramids are considered a National Natural Landmark by the US Department of the Interior. Though they do technically sit on private property, the owners are welcome to visitors as long as they are respectful to the ancient rocks. True, the rocks may be a little out of the way to get to, but if you are ever passing through Kansas, make a stop in Gove County. There, you can appreciate what our continent used to consist of, and what millions of years of erosion have brought it to look like today.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">--Pete D

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Photo Credit: <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Scott Branine <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> http://tinyurl.com/cujfcy6

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">References: <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">1. http://www.washburn.edu/cas/art/cyoho/archive/KStravel/bigrocks/pyramids.html <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">2. http://www.geographic.org/geographic_names/usaname.php?uni=471391&fid=usageo_423 <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">3. http://www.naturalkansas.org/monument.htm <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">4. @http://www.keystonegallery.com/area/monument_rocks.html <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">5. @http://www.kansastravel.org/monumentrocks.htm



<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Zhangye Danxia Landform Geological Park, China

<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Over the course of 24 million years, deposits of various sedimentary rocks were laid down upon the modern Gansu Province of China. Over time, these formed into red conglomerate rock, sand conglomerate rock and sandstone. Hence, the landscape of this region has a significant spectrum of rock texture, ranging from its clastic lithified rock to the fine <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> grained sandstone.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Many geological factors played a role into this location's strange nature. The regional tectonic lines beneath the surface controlled both the pattern and shape that these rock formations took. However, while active movements underground shaped the surface, exogenous factors above the surface played a major role as well. Alluvial corrosion and natural weathering created a perfect environment for landslides. The steep scarps are most often the results of these "eboulements".

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">While all this was occurring, a landscape was being sculpted that contained cave holes, rock pillars, peaks and valleys, jagged scarps, and a varying array of terrain from rough to smooth. The amazing "layer cake" of colors was formed by the local tectonic plates in the same way that the Himalayan mountains were formed, revealing the wide range of clastic and fine grained sedimentary rock. Instead of being one hunk of rock, erosion forces like wind and rain carved the landscape, accomplishing the task of creating stunning towers, ravines, waterfalls, and more.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Today, the regions is a protected geological park, currently growing as a tourist location. Artists envy this natural spilled palette of rock. The combination of a beautiful landscape and amazing cultural scenery drives increased tourism development. Yet, as the small town of Zhangye slowly becomes awakened by the touristic boom of its natural wonder, the Danxia Landforms retain their natural beauty.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">--Sam J.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">Image Credit: Amos Chapple, The Telegraph

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">References:

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> @http://en.cnki.com.cn/Article_en/CJFDTOTAL-DLKX200003001.htm

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> http://www.telegraph.co.uk/travel/picturegalleries/9550531/Colourful-rock-formations-in-the-Zhangye-Danxia-Landform-Geological-Park.html?frame=2343145

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;"> @http://www.amazingworldonline.com/2013/03/zhangye-danxia-landform-geological-park.html

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif;">

<span style="background-color: #ffffff; color: #333333; display: block; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.8px;">TauTona Mine- Deepest mine in the world

Carletonville, South Africa is home to the world's deepest mine. This gold mine extends 3.9 km below the surface of the earth. That’s about 13 Eiffel Towers stacked one on top of the other.

According to National Geographic, TauTona is in the area of South Africa that has produced over half of all the gold that has ever been mined.

<span class="text_exposed_show">Between 3000 and 2700 million years ago, the Witwatersrand bodies of ore were deposited. The majority of the layers of ore are conglomerate with small stones of quartz and fine-grained silica-rich microcrystalline (chert) in a matrix of quartz grains and sulphides (primarily pyrite).

The layer of ore (from which the gold is mined) that extends from Johannesburg doesn't lie close to the Earth’s surface. It lies more or less at an acute angle below the surface. Furthermore the layer is only 25 cm thick. Nevertheless, the mine processes 140 000 tons of ore a month (with a yield of 1.6 tons of gold).

Three shafts exist as it is not possible to carry workers to the deepest depths of the mine. The journey down the shafts can take up to an hour even though the elevators or cages travel at 16 meters per second (57.6 km/h). The labyrinth of the tunnels that make up the mine collectively cover 800 km. A four hour commute awaits miners who work at the deepest parts of the mine.

The mine experiences an average of 10 underground earthquakes a day. Geologists and engineers use geophones planted deep into the rock face to monitor this seismic activity.

In Setswana (language) TauTona means “great lion”.

<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">♞ <span style="background-color: #ffffff; color: #333333; display: block; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.8px;">Renesh T

Check out our earlier post by TEL

@http://www.facebook.com/photo.php?fbid=370408159686901&set=a.486796331381416.1073741825.352857924775258&type=3&theater

<span class="text_exposed_show">Image credit

@http://www.mining-technology.com/projects/tautona_goldmine/tautona_goldmine3.html

References and further reading

National Geographic - Megastructures- TauTona, City of Gold (2005)

http://www.mining-technology.com/projects/tautona_goldmine/ http://www.infomine.com/minesite/minesite.asp?site=tautona http://researchspace.csir.co.za/dspace/bitstream/10204/1813/1/GAP709a.pdf http://www.dtic.mil/dtic/tr/fulltext/u2/a526774.pdf @http://info.goldavenue.com/info_site/in_mine/in_min_sa_geol.htm @http://global.britannica.com/EBchecked/topic/211535/fluvial-process <span style="background-color: #ffffff; color: #333333; display: block; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.8px;"> <span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.8px;"> Harmony Borax Works Article <span class="text_exposed_show"> : <span style="background-color: #ffffff; color: #333333; display: block; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.8px;">[|Harmony Borax Works] <span style="background-color: #ffffff; color: #333333; display: block; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.8px;">media type="custom" key="27790631" <span style="background-color: #ffffff; color: #333333; display: block; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.8px;"> =<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.8px;">Canada's Tar Sands Landscape from the air: = =<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.8px;">[|Canada's Tar Sands Landscape from the air] = <span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.8px;">media type="custom" key="27790641"

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