Anthony Knockaert’s free-kick on the stroke of half-time put Brighton ahead at the Amex Stadium.The visitors were on top for much of the first half and Conor Washington, restored to the starting line-up and looking for his first QPR goal, had a chance to put them ahead.Massimo Luongo’s ball into the box fell to the striker, who turned and fired over the bar.Rangers created other first-half openings, with Alejandro Faurlin firing over and delivering a corner that was headed straight at keeper David Stockdale by Clint Hill.Stockdale was also called into action to keep out a shot from Matt Phillips after the QPR wide-man had closed down Bruno.Promotion-chasing Brighton, who could move back into the top two if they win, barely troubled the R’s before James Wilson blasted narrowly wide 10 minutes before the break.Rangers, who have played well so far, responded strongly and Phillips sent a shot just over.Albion finished the half strongly, though, and Alex Smithies was well positioned to keep out Lewis Dunk’s header from Knockaert’s corner.But Smithies was unable to rescue his team after Nedum Onuoha was adjudged to have fouled Jiri Skalak. Knockaert beautifully curled the resulting free-kick into the top corner.QPR: Smithies; Onuoha, Hall, Hill, Perch: Henry, Faurlin; Luongo, Hoilett, Phillips; Washington.Subs: Ingram, Kpekawa, Gladwin, El Khayati, Petrasso, Chery, Polter.Follow West London Sport on TwitterFind us on Facebook
Reprinted from June 27, 2003, this mystery is worth considering still. What caused these global deposits that are not being formed today?6/27/03 — R. H. Dott, Jr (Univ. of Wisconsin) has a problem. He’s been trying to explain a geological puzzle for 50 years, and it is still unresolved. All around the world, sandstones are found that are “remarkably pure” that “seem nonactualistic” (jargon for “They can’t really be there”). These pure quartz arenites, as they are called, were considered a major puzzle half a century ago, when Dr. Dott was a student. Some of them “extend laterally over vast areas encompassing one or several states,” and they cover vast areas of Africa and Arabia, the Great Lakes region, South America, Australia, and more. These “sheet sands” (as they are nicknamed) are part of a notorious gang: “Together with the origin of dolomite, red beds, black shale, and banded iron formation, they made up a group of seemingly intractable geological problems” (emphasis added in all quotes).Dott tells autobiographically, “Having lived literally upon quartz-rich sandstones for almost 50 years, I have come to regard supermature quartz arenites as nature’s finest distillate—almost as remarkable as a pure single malt Scotch whiskey.” In the July 2003 Journal of Geology, he has written a lengthy paper addressing the mystery of the quartz arenites, and the status of current hypotheses. It amounts to a veritable State of the Century address to sandstone geologists. He explains the puzzle in the Introduction:What is the quartz arenite problem? Foremost is the extreme compositional maturity of sandstones composed of more than 95% quartz. Furthermore, the quartz consists almost exclusively of grains of unstrained, single-crystal units. Very rare lithic [rock] fragments consist only of durable polycrystalline quartz types such as chert or vein quartz. In addition, the extremely rare accessory mineral suite (generally <0.05% by weight) is dominated by durable zircon, tourmaline, ilmenite, and leucoxene. Where present, associated conglomerates also consist only of durable clasts of vein quartz, quartzite, or chert. How can we explain the complete disposal of at least 75% of any ultimate parent igneous or metamorphic rock to yield a residue that is at least 95% quartz sand? Extreme textural maturity is also characteristic of many, but not all, examples. A high degree of sorting has always been emphasized, with high rounding being common but not universal. Both properties imply much abrasion by one or more of nature’s most physically vigorous processes, such as surf and strong eolian [wind] or aqueous currents. Dr. Dott mentions additional puzzles about these formations:Thin, tabular geometry: layers tens or hundreds of meters thick, very flat over vast regions, yet Paleozoic in age – i.e., prior to the emergence of land plants.A paucity of associated shale, in contrast to other sandstones.Interstratified with shallow marine carbonate strata.A lack of volumetrically significant analogues forming today (i.e., nothing on that scale can be seen forming now). This implies weathering processes orders of magnitude greater in the past.Very rare body fossils, and some burrows.Frosting of the grains, making them rough on microscopic scales.Underlying mature shale high in kaolinite (clay) or illite.Even more pure quartz arenites, up to thousands of meters thick, in Precambrian strata.Many of them underlain by paleosols (ancient soils) that show a high degree of chemical maturation.According to Dott, wind erosion is the most efficient, but not the only, agent for rounding of the sand grains. Some geologists have resorted to theories of multicycling to explain the weathering and maturation of the grains, but theories of single cycles “under intense tropical weathering” also go back decades, and he cannot rule them out. (Though there are small examples forming in isolated river deltas today, their grains are not nearly as rounded.) The chemical maturation suggests that impurities were dissolved away, a process called diagenesis, but that is not possible in the presence of wind.The paradox of the compositional maturation of the sand “seems to require some additional factor to reconcile geomorphic conditions that could have enhanced the transport and abrasion of enormous volumes of pure quartz sand, on the one hand, but could have allowed exceptional chemical maturation of soils on the other hand, as indicated by profiles beneath, and the composition of pelitic [mud, clay] strata interstratified within, many quartz arenites.”Dott introduces his theory at this point. To solve the paradox, he postulates thin microbial crusts or mats of cyanobacteria formed over the soils, similar to the stromatolites and cryptogamic soils seen forming in some regions today. These might have protected the underlying paleosols while allowing wind transport of sand above. The lack of trees and shrubs might have allowed much more energetic winds. This assumes that the first land invaders were cyanobacteria, although “the fossil record has seemed mute” on this point. In a sense, these crusts formed a cap that protected the lower strata while the high winds deposited the sand (although he does not propose sources for the sand).He ends with one other paradox; without land plants, unless the landscape were perfectly flat, how could it be stable enough to allow the chemical weathering of both the sand and underlying paleosols? “The abundance of medium-grained to coarse-grained sand and associated pebbles required streams with sufficient gradients to transport such materials, which in turn points to at least moderate topographic relief, which exacerbates the stabilization problem,” he says. His best guess, in conclusion, is the microbial mat theory; this formed a crust enough to stabilize the landscapes for up to two billion years while these puzzling structures formed. This was an interesting paper about an interesting puzzle that some readers may wish to investigate further. Does his explanation satisfy you? Notice how these formations are huge, and exist on every continent. Notice how thick and flat they are. Notice how they are interspersed with clays and soils, yet are exceptionally pure, “nature’s finest distillate.” Notice how they give evidence of being deposited via nature’s most vigorous and energetic forces. Doesn’t this sound like global cataclysm? Since catastrophism is back in vogue, should we not follow the evidence where it leads?(Visited 830 times, 1 visits today)FacebookTwitterPinterestSave分享0
Location:AlabamaFavorite Points:197Love stumbling upon the unexpected? There’s a GeoTour for that! A Dash of the Unexpected GeoTour is located in Northern Alabama in the southern foothills of the Appalachian Mountains and along the rushing waters of the Tennessee River. The 31 geocaches in the GeoTour capture the best parts of the region. There are views of waterfalls, civil war battle sites, and at the right time of year you may stumble upon a friendly southern-style barbecue. SharePrint RelatedA Dash of the Unexpected GeoTour (GT7B)March 5, 2019In “GeoTours”Experience Cortland GeoTour (GT21)August 31, 2017In “GeoTours”Spokane History GeoTourJanuary 8, 2016In “Community” Great geocaches on this GeoTour:Joe Wheeler State ParkTraditional Cache | GC6XGN4 | by NorthAL | D1.5/T1.5 Along the 652-mile (1050 km) long Tennessee River, Joe Wheeler State Park has beautiful vistas, campgrounds, watersports, and several geocaches for all of your outdoor adventure needs. This cache leads you just off the walking path to the water’s edge, where you’ll have a spectacular view of the river and Appalachian foothills.D.O.U. Key Underwood Coon Dog Memorial GraveyardTraditional Cache | GC6Y6E3| by NorthAL| D2.5/T2.5A coon dog, or sometimes referred to as a coonhound, is a breed of hunting dog that hunts raccoons.This geocache tells the story of a man and his beloved pup, “Troop” dating back to the 1920’s. Known for his perennial hunting skills and kindness to others, Troop was admired by all who met him. After 15 years of companionship it came time for Underwood to lay his friend to rest at the campsite where they spent a lot of time together. What Underwood did not know was that others would follow suit by burying their beloved dogs at the campsite. Today the graveyard is the only one of its kind and attracts dog lovers across the United States. While searching for the cache in the area you can pay homage to many great dogs buried here.North Alabama Civil War Trail 1818 FarmMulti-Cache | GC669BM | by NorthAL | D1.5/T1.5 1818 Farms is a Multi-Cache along the North Alabama Civil War Trail in the historic town of Mooresville, Alabama. The number of caches in Mooresville out-number the population—there are 333 caches and only 58 people! You can see a variety of animals sheep, goats, cats, hens, a pot-bellied pig, mini pigs, and two Great Pyrenees guardian dogs. 5 Reasons to visit Northern Alabama:U.S. Space & Rocket CenterGorgeous waterfalls and parksFun festivals and events throughout the yearMouth watering BBQUnique craft breweries and wineriesPrizes:Geocachers receive a geocoin for 60 points. Geocachers receive a geocoin and a T-shirt for 75 points.What geocachers say:On an awesome adventure with our best caching friends, to complete the “Dash of the Unexpected”. Fantastic! Bit chilly today but still…awesome place! Thanks for placing and maintaining this cache.” -Nurse 1The amazing, outstanding, demanding, commanding and downright awesome Team Bald Mob has taken on yet another Geotour!! We came, we saw, we kicked its well you know. We left our mark for all to see!! Thank you NorthAl for giving us another opportunity to show just how great we are!! Maybe now we can get one in the southern part of Alabama!! TFTC and as always Roll Tide!!!” -GeoACT3This was the last cache in the series for us. Well the last we found. The challenge is complete and the coin in collected. Thank you to the north Alabama mountain and lakes travel bureau. So much fun competing this series. Went all over the state and had so much fun. Thank you for all of the great caches.” -The4LollyGaggersFind out more about the Dash of the Unexpected GeoTour here.Note: All the above information was provided by the GeoTour host. Copy has been edited by Geocaching HQ.Share with your Friends:More
On Sunday India under-19 cricket captain Unmukt Chand, scored a brilliant knock in the final of the U-19 World Cup in Townsville against hosts Australia. The knock helped India to an emphatic six wicket victory.No sooner had the team won the U-19 World Cup, that congratulatory messages started pouring in along came cash awards – it was a dream come true for skipper Unmukt Chand.All that would seem cake walk for Unmukt, who is busy fighting another battle. The St Stephen’s College student had been debarred from giving his exams as he was short of the required attendance.The BA first year student was barred from taking the second semester exam because of low attendance, following which Unmukt approached the Delhi High Court.Though the court has allowed him to write the exams, he would only be able to appear in two out of the prescribed four in the semester as he got late in approaching the court.Unmukt apparently had just eight per cent attendance in college. The next hearing for the case is on September 14.