Mount Blackburn is the highest peak in the Wrangell Mountains of Alaska in the United States. It is the twelfth-highest peak in North America; the mountain is an old, eroded shield volcano, the second-highest volcano in the U. S. behind Mount Bona and the fifth-highest in North America. It was named in 1885 by Lt. Henry T. Allen of the U. S. Army after Joseph Clay Stiles Blackburn, a U. S. senator from Kentucky. It is located in the heart of Wrangell – St. Elias National Park, the largest national park in the country; the mountain's massif is covered entirely by icefields and glaciers, is the principal source of ice for the Kennicott Glacier, which flows southeast over 20 miles to just above the town of McCarthy. The mountain contributes a large volume of ice to the north-flowing Nabesna Glacier and the Kuskulana Glacier system. Mount Blackburn is a large, dramatic peak, with great local relief and independence from higher peaks, its west face drops over 11,000 ft to the Kuskulana Glacier in less than 4 horizontal miles.
Its other faces drop 8,000–10,000 ft, all in less than 8 miles. The toe of the Kuskulana Glacier, less than 12 miles from the summit, lies at an elevation of 2,400 ft, giving a rise of 14,000 ft. While these figures speak to the peak's relief, one measure of its independence is that it is the 50th-most topographically prominent peak in the world; the western of Blackburn's two summits is the mountain's highest point, a fact, not understood until the 1960s when new USGS maps were published. The first ascent of the west peak, hence Mount Blackburn, was done on May 30, 1958, by Bruce Gilbert, Dick Wahlstrom, Hans Gmoser, Adolf Bitterlich, Leon Blumer via the North Ridge; this team made the first ascent of Blackburn, but did not know it at the time due to the incorrect identification of the highest point. In fact, Blumer's article in the 1959 American Alpine Journal is titled "Mount Blackburn – Second Ascent." Kennedy Peak, or East Blackburn, 16,286 ft, is the eastern summit and was thought to be the highest point.
The first ascent of this summit was made in 1912 by Dora Keen and George Handy via the Kennicott Glacier and East Face. This heady exploit was ahead of its time. Dora Keen, driven by a deep desire for the climb, solicited miners from the nearby Kennecott Copper Mines, forged a route up the crevassed East Face to the East Peak, but did not traverse over to the West Peak. Keen went on to write a famous article for the Saturday Evening Post titled, "First up Mount Blackburn." In 1912, Keen and Handy thought. Mount Blackburn represents the eroded core of a shield volcano; because it is shrouded in permanent ice, its internal structure cannot be determined. It is believed to have a summit caldera modified by glaciation; the oldest rocks in the area are granites, about 4.2 million years old, representing an intrusive mass. The majority of the mountain is 3.4 million year old granite. From this it is inferred that a caldera collapse took place between 4.2 and 3.4 million years ago, after which activity ceased.
Today's standard route on the peak is the 1958 ascent route, the North Ridge, approached from the Nabesna Glacier, on the north side of the mountain, opposite from Keen and Hardy's route. The route starts from an airstrip on the glacier at an altitude of 7,200 feet, it is a moderate climb by Alaskan standards. List of mountain peaks of North America List of mountain peaks of the United States List of mountain peaks of Alaska List of the highest major summits of the United States List of the most prominent summits of the United States List of the most isolated major summits of the United States List of volcanoes in the United States Wood, Michael. Alaska: A Climbing Guide. Mountaineers Books. ISBN 0-89886-724-X. Richter, Donald H.. Guide to the Volcanoes of the Western Wrangell Mountains, Alaska. USGS Bulletin 2072. Winkler, Gary R.. A Geologic Guide to Wrangell—Saint Elias National Park and Preserve, Alaska: A Tectonic Collage of Northbound Terranes. USGS Professional Paper 1616. ISBN 0-607-92676-7.
Richter, Donald H.. Geologic Map of the Wrangell-Saint Elias National Park and Preserve, Alaska. USGS Scientific Investigations Map 2877
Mount Bona is one of the major mountains of the Saint Elias Mountains in eastern Alaska, is the fifth-highest independent peak in the United States. Mount Bona and its adjacent neighbor Mount Churchill are both large ice-covered stratovolcanoes. Bona has the distinction of being the highest volcano in the United States and the fourth-highest in North America, outranked only by the three highest Mexican volcanoes, Pico de Orizaba, Popocatépetl, Iztaccíhuatl, its summit is a small stratovolcano on top of a high platform of sedimentary rocks. The mountain's massif is covered entirely by icefields and glaciers, it is the principal source of ice for the Klutlan Glacier, which flows east for over 40 miles into the Yukon Territory of Canada; the mountain contributes a large volume of ice to the north-flowing Russell Glacier system. Mount Bona was named by Prince Luigi Amedeo, Duke of the Abruzzi in 1897, who saw the peak while making the first ascent of Mount Saint Elias about 80 miles to the southeast.
He named it after his racing yacht. The mountain was first climbed in 1930 by Allen Carpé, Terris Moore, Andrew Taylor, from the Russell Glacier on the west of the peak; the current standard route is the East Ridge. List of mountain peaks of North America List of mountain peaks of the United States List of mountain peaks of Alaska List of the highest major summits of the United States List of the most prominent summits of the United States List of the most isolated major summits of the United States List of volcanoes in the United States List of mountain peaks of North America List of mountain peaks of the United States List of mountain peaks of Alaska Mount Bona at the Alaska Volcano Observatory "Mount Bona". Bivouac.com. Retrieved 2009-01-06. "Churchill". Global Volcanism Program. Smithsonian Institution. Retrieved 2009-01-06
Scheelite is a calcium tungstate mineral with the chemical formula CaWO4. It is an important ore of tungsten. Well-formed crystals are sought by collectors and are fashioned into gemstones when suitably free of flaws. Scheelite has been synthesized using the Czochralski process, it was used in radium paint in the same fashion as was zinc sulphide, Thomas Edison invented a fluoroscope with a calcium tungstate-coated screen, making the images six times brighter than those with barium platinocyanide. Its crystals are in the tetragonal crystal system. Colors include golden yellow, brownish green to dark brown, pinkish to reddish gray and colorless. Transparency ranges from translucent to transparent and crystal faces are lustrous. Scheelite possesses its fracture may be subconchoidal to uneven, its specific gravity is high at 5.9–6.1 and its hardness is low at 4.5–5. Aside from pseudo-octahedra, scheelite may be columnar, tabular or massive in habit. Druzes are quite rare and occur exclusively at Zinnwald, Czech Republic.
Twinning is commonly observed and crystal faces may be striated. Scheelite is brittle. Gems cut from transparent material are fragile. Scheelite's refractive index and dispersion are both moderately high; these factors combine to result in scheelite's high lustre and perceptible "fire", approaching that of diamond. Scheelite fluoresces under shortwave ultraviolet light, the mineral glows a bright sky-blue; the presence of molybdenum trace impurities results in a green glow. Fluorescence of scheelite, sometimes associated with native gold, is used by geologists in the search for gold deposits. Scheelite occurs in contact metamorphic skarns. Temperature and pressure of formation is from 200 to 1,500 bars. Typical mineral association includes cassiterite, topaz, apatite, quartz, grossular–andradite, diopside and tremolite. Scheelite occurs in tin-bearing veins. Fine crystals have been obtained from Caldbeck Fells in Cumbria, Zinnwald/Cínovec and Elbogen in Bohemia, Guttannen in Switzerland, the Riesengebirge in Silesia, Dragoon Mountains in Arizona and elsewhere.
At Trumbull in Connecticut and Kimpu-san in Japan large crystals of scheelite altered to wolframite have been found: those from Japan have been called “reinite.” It was mined until 1990 at King Island, Glenorchy in Central Otago and Macraes Flat in North Otago and at The Golden Bar mine at Dead Horse Creek during World War 1 in Nelson, New Zealand. There is a high concentration of Scheelite in Northeast of Brazil in the Currais Novos mine in Rio Grande do Norte State. Scheelite was first described in 1781 for an occurrence in Mount Bispbergs klack, Säter, Dalarna and named for Carl Wilhelm Scheele. Owing to its unusual heaviness, it had been given the name tungsten by the Swedes, meaning “heavy stone.” The name was used to describe the metal, while the ore itself was given the name scheelerz or scheelite. Although it is now uncommon as a diamond imitation, synthetic scheelite is offered as natural scheelite, collectors may thus be fooled into paying high prices for them. Gemologists distinguish natural scheelite from synthetic material by microscopic examination: Natural material is seldom without internal growth features and inclusions, while synthetic material is very clean.
Distinctly artificial curved striae and clouds of minute gas bubbles may be observed in synthetic scheelite. The visible absorption spectrum of scheelite, as seen by a hand-held spectroscope, may be of use: most natural stones show a number of faint absorption lines in the yellow region of the spectrum due to praseodymium and neodymium trace impurities. Conversely, synthetic scheelite is without such a spectrum; some synthetics may however be doped with neodymium or other rare-earth elements, but the spectrum produced is unlike that of natural stones. Anderson, B. W. Jobbins, E. A.. Gem testing. Butterworth & Co Ltd, Great Britain. ISBN 0-408-02320-1
Mount Lucania is the third-highest mountain located in Canada. A long ridge connects Mount Lucania with the fifth-highest in Canada. Lucania was named by the Duke of Abruzzi, as he stood on the summit of Mount Saint Elias on July 31, 1897, having just completed the first ascent. Seeing Lucania in the far distance, beyond Mount Logan, he named it "after the ship on which the expedition had sailed from Liverpool to New York," the RMS Lucania; the first ascent of Mount Lucania was made in 1937 by Robert Hicks Bates. They used an airplane to reach 2,670 m above sea level. Washburn called upon Bob Reeve, a famous Alaskan bush pilot, who replied by cable to Washburn, "Anywhere you'll ride, I'll fly"; the ski-equipped Fairchild F-51 made several trips to the landing site on the glacier without event in May, but on landing with Washburn and Bates in June, the plane sank into unseasonal slush. Washburn and Reeve pressed hard for five days to get the airplane out and Reeve was able to get the airplane airborne with all excess weight removed and with the assistance of a smooth icefall with a steep drop.
Washburn and Bates continued on foot to make the first ascent of Lucania, in an epic descent and journey to civilization, they hiked over 150 miles through the wilderness to safety in the small town of Burwash Landing in the Yukon. The second ascent of Lucania was made in 1967 by Jerry Halpern, Mike Humphreys, Gary Lukis, Gerry Roach. List of mountain peaks of Canada David Roberts, Escape from Lucania: An Epic Story of Survival, Simon & Schuster, ISBN 0-7432-2432-9
In modern mapping, a topographic map is a type of map characterized by large-scale detail and quantitative representation of relief using contour lines, but using a variety of methods. Traditional definitions require a topographic map to show both man-made features. A topographic survey is published as a map series, made up of two or more map sheets that combine to form the whole map. A contour line is a line connecting places of equal elevation. Natural Resources Canada provides this description of topographic maps:These maps depict in detail ground relief, forest cover, administrative areas, populated areas, transportation routes and facilities, other man-made features. Other authors define topographic maps by contrasting them with another type of map. However, in the vernacular and day to day world, the representation of relief is popularly held to define the genre, such that small-scale maps showing relief are called "topographic"; the study or discipline of topography is a much broader field of study, which takes into account all natural and man-made features of terrain.
Topographic maps are based on topographical surveys. Performed at large scales, these surveys are called topographical in the old sense of topography, showing a variety of elevations and landforms; this is in contrast to older cadastral surveys, which show property and governmental boundaries. The first multi-sheet topographic map series of an entire country, the Carte géométrique de la France, was completed in 1789; the Great Trigonometric Survey of India, started by the East India Company in 1802 taken over by the British Raj after 1857 was notable as a successful effort on a larger scale and for determining heights of Himalayan peaks from viewpoints over one hundred miles distant. Topographic surveys were prepared by the military to assist in planning for battle and for defensive emplacements; as such, elevation information was of vital importance. As they evolved, topographic map series became a national resource in modern nations in planning infrastructure and resource exploitation. In the United States, the national map-making function, shared by both the Army Corps of Engineers and the Department of the Interior migrated to the newly created United States Geological Survey in 1879, where it has remained since.1913 saw the beginning of the International Map of the World initiative, which set out to map all of Earth's significant land areas at a scale of 1:1 million, on about one thousand sheets, each covering four degrees latitude by six or more degrees longitude.
Excluding borders, each sheet was up to 66 cm wide. Although the project foundered, it left an indexing system that remains in use. By the 1980s, centralized printing of standardized topographic maps began to be superseded by databases of coordinates that could be used on computers by moderately skilled end users to view or print maps with arbitrary contents and scale. For example, the Federal government of the United States' TIGER initiative compiled interlinked databases of federal and local political borders and census enumeration areas, of roadways and water features with support for locating street addresses within street segments. TIGER was used in the 1990 and subsequent decennial censuses. Digital elevation models were compiled from topographic maps and stereographic interpretation of aerial photographs and from satellite photography and radar data. Since all these were government projects funded with taxes and not classified for national security reasons, the datasets were in the public domain and usable without fees or licensing.
TIGER and DEM datasets facilitated Geographic information systems and made the Global Positioning System much more useful by providing context around locations given by the technology as coordinates. Initial applications were professionalized forms such as innovative surveying instruments and agency-level GIS systems tended by experts. By the mid-1990s user-friendly resources such as online mapping in two and three dimensions, integration of GPS with mobile phones and automotive navigation systems appeared; as of 2011, the future of standardized, centrally printed topographical maps is left somewhat in doubt. Topographic maps have multiple uses in the present day: any type of geographic planning or large-scale architecture; the various features shown on the map are represented by conventional symbols. For example, colors can be used to indicate a classification of roads; these signs are explained in the margin of the map, or on a separately published characteristic sheet. Topographic maps are commonly called contour maps or topo maps.
In the United States, where the primary national series is organized by a strict 7.5-minute grid, they are called topo quads or quadrangles. Topographic maps conventionally show land contours, by means of contour lines. Contour lines are curves. In other words, every point on the marked line of 100 m elevation is 100 m above mean sea level; these maps show
John Muir Wilderness
The John Muir Wilderness is a wilderness area that extends along the crest of the Sierra Nevada of California for 90 miles, in the Inyo and Sierra National Forests. Established in 1964 by the Wilderness Act and named for naturalist John Muir, it contains 581,000 acres; the wilderness lies along the eastern escarpment of the Sierra from near Mammoth Lakes and Devils Postpile National Monument in the north, to Cottonwood Pass near Mount Whitney in the south. The wilderness area spans the Sierra crest north of Kings Canyon National Park, extends on the west side of the park down to the Monarch Wilderness; the wilderness contains some of the most spectacular and highest peaks of the Sierra Nevada, with 57 peaks over 13,000 feet in elevation. The peaks are made of granite from the Sierra Nevada Batholith, are shaped by glacial action; the southernmost glacier in the United States, the Palisade Glacier, is contained within the wilderness area. Notable eastside glaciated canyons are drained by Rock, McGee, Bishop Creeks.
The eastern escarpment in the wilderness rises from 6,000 to 8,000 feet from base to peak, in 5 to 6 miles. The Sierra crest contains peaks from 12,000 to 14,000 feet in elevation, including Mount Whitney, the highest peak in the continental United States. Other notable mountains in the wilderness area include the Mount Humphreys. Mount Muir is located 2 miles south of Mount Whitney. Mount Williamson is the second-highest peak in the wilderness, at 14,375 feet: it rises in one continuous sweep of granite from the floor of the Owens Valley to a peak just east of the main range; the John Muir Wilderness contains the largest contiguous area above 10,000 feet in the continental United States. It contains large areas of subalpine meadows and fellfields above 10,800 feet, containing stands of whitebark and foxtail pine. From 9,000 feet to 10,800 feet, the wilderness is dominated by lodgepole pines. Below the lodgepole forest is forest dominated by Jeffrey pine. Common animals in the wilderness include yellow-bellied marmots, golden-mantled ground squirrels, Clark's nutcrackers, golden trout, black bears.
The wilderness area includes California bighorn sheep zoological areas, which are set aside for the protection of the species. The wilderness contains 589.5 miles of hiking trails, including the John Muir Trail and the Pacific Crest Trail, which run through the wilderness from north to south. The John Muir Wilderness is the second most-visited wilderness in the United States, quota are required for overnight use on all trailheads. Duck Lake Lake Virginia Squaw Lake Bibliography of the Sierra Nevada, for further reading Wilderness.net TopoQuest map
Tungsten, or wolfram, is a chemical element with symbol W and atomic number 74. The name tungsten comes from the former Swedish name for the tungstate mineral scheelite, tung sten or "heavy stone". Tungsten is a rare metal found on Earth exclusively combined with other elements in chemical compounds rather than alone, it was identified as a new element in 1781 and first isolated as a metal in 1783. Its important ores include scheelite; the free element is remarkable for its robustness the fact that it has the highest melting point of all the elements discovered, melting at 3422 °C. It has the highest boiling point, at 5930 °C, its density is 19.3 times that of water, comparable to that of uranium and gold, much higher than that of lead. Polycrystalline tungsten is an intrinsically hard material, making it difficult to work. However, pure single-crystalline tungsten can be cut with a hard-steel hacksaw. Tungsten's many alloys have numerous applications, including incandescent light bulb filaments, X-ray tubes, electrodes in gas tungsten arc welding and radiation shielding.
Tungsten's hardness and high density give it military applications in penetrating projectiles. Tungsten compounds are often used as industrial catalysts. Tungsten is the only metal from the third transition series, known to occur in biomolecules that are found in a few species of bacteria and archaea, it is the heaviest element known to be essential to any living organism. However, tungsten interferes with molybdenum and copper metabolism and is somewhat toxic to more familiar forms of animal life. In its raw form, tungsten is a hard steel-grey metal, brittle and hard to work. If made pure, tungsten retains its hardness, becomes malleable enough that it can be worked easily, it is worked by drawing, or extruding. Tungsten objects are commonly formed by sintering. Of all metals in pure form, tungsten has the highest melting point, lowest vapor pressure, the highest tensile strength. Although carbon remains solid at higher temperatures than tungsten, carbon sublimes at atmospheric pressure instead of melting, so it has no melting point.
Tungsten has the lowest coefficient of thermal expansion of any pure metal. The low thermal expansion and high melting point and tensile strength of tungsten originate from strong covalent bonds formed between tungsten atoms by the 5d electrons. Alloying small quantities of tungsten with steel increases its toughness. Tungsten exists in two major crystalline forms: α and β; the former is the more stable form. The structure of the β phase is called A15 cubic. Contrary to the α phase which crystallizes in isometric grains, the β form exhibits a columnar habit; the α phase has one third of the electrical resistivity and a much lower superconducting transition temperature TC relative to the β phase: ca. 0.015 K vs. 1–4 K. The TC value can be raised by alloying tungsten with another metal; such tungsten alloys are sometimes used in low-temperature superconducting circuits. Occurring tungsten consists of four stable isotopes and one long-lived radioisotope, 180W. Theoretically, all five can decay into isotopes of element 72 by alpha emission, but only 180W has been observed to do so, with a half-life of ×1018 years.
The other occurring isotopes have not been observed to decay, constraining their half-lives to be at least 4 × 1021 years. Another 30 artificial radioisotopes of tungsten have been characterized, the most stable of which are 181W with a half-life of 121.2 days, 185W with a half-life of 75.1 days, 188W with a half-life of 69.4 days, 178W with a half-life of 21.6 days, 187W with a half-life of 23.72 h. All of the remaining radioactive isotopes have half-lives of less than 3 hours, most of these have half-lives below 8 minutes. Tungsten has 11 meta states, with the most stable being 179mW. Elemental tungsten resists attack by oxygen and alkalis; the most common formal oxidation state of tungsten is +6, but it exhibits all oxidation states from −2 to +6. Tungsten combines with oxygen to form the yellow tungstic oxide, WO3, which dissolves in aqueous alkaline solutions to form tungstate ions, WO2−4. Tungsten carbides are produced by heating powdered tungsten with carbon. W2C is resistant to chemical attack, although it reacts with chlorine to form tungsten hexachloride.
In aqueous solution, tungstate gives the heteropoly acids and polyoxometalate anions under neutral and acidic conditions. As tungstate is progressively treated with acid, it first yields the soluble, metastable "paratungstate A" anion, W7O6–24, which over time converts to the less soluble "paratungstate B" anion, H2W12O10–42. Further acidification produces the soluble metatungstate anion, H2W12O6–40, after which equilibrium is reached; the metatungstate ion exists as a symmetric cluster of twelve tungsten-oxygen octahedra known as the Keggin anion. Many other polyoxometalate anions exist as metastable species; the inclusion of a different atom such as phosphorus in place of the two central hydrogens in metatungstate produces a wide v