Every blogger knows the challenge. What shall I blog about next? What photos should I use? By the time the end of the year rolls around, there are always a few posts and photos that never quite made it. And so, with this final post of the year, here are a few from here and there, all from 2014. Please visit the same for 2013 here and 2012 here.
January
A Lustrous Pearl for an Illustrious New Year
My wife and I ushered in the New Year with our traditional early dinner at a wonderful local restaurant. To our surprise, one of the saltwater oysters in her appetizer contained an opaque white, natural pearl - a one-in-a-million chance.
Pearls begin as foreign bodies within the mantle of a mollusk. The bivalve’s response is to secrete layer after layer of nacre (NAY-ker), a hard crystalline substance around the irritant for protection. The result is a pearl, which is similar in finish to the shiny inside of oysters and mussels, known as mother of pearl and can take 5 to 20 years to form (1 to 6 years for freshwater pearls). Light passing through the nacreous substance is reflected and refracted, which gives the pearl its luster and iridescence. This is because the thickness of the platelets of aragonite - a form of calcium carbonate (the other being calcite) - is close to the wavelength of visible light. Unlike gemstones that are cut and polished to bring out their beauty, pearls require no such treatment.
Finding a pearl is considered to be good luck, and looking back on this year, I would affirm that superstition.
Pearls begin as foreign bodies within the mantle of a mollusk. The bivalve’s response is to secrete layer after layer of nacre (NAY-ker), a hard crystalline substance around the irritant for protection. The result is a pearl, which is similar in finish to the shiny inside of oysters and mussels, known as mother of pearl and can take 5 to 20 years to form (1 to 6 years for freshwater pearls). Light passing through the nacreous substance is reflected and refracted, which gives the pearl its luster and iridescence. This is because the thickness of the platelets of aragonite - a form of calcium carbonate (the other being calcite) - is close to the wavelength of visible light. Unlike gemstones that are cut and polished to bring out their beauty, pearls require no such treatment.
Finding a pearl is considered to be good luck, and looking back on this year, I would affirm that superstition.
February
William Smith’s Map That Changed the World
"Sing, cockle-shells and oyster-banks,
Sing, thunder-bolts and screw-stones,
To Father Smith we owe our thanks
For the history of a few stones."
Anniversary Dinner by A.C. Ramsey, 1854.
This eight by six-foot Delineation of the Strata of England and Wales with Part of Scotland is easily mistaken for a modern geologic map. Yet, it was created by William Smith in 1815 and was the first national-scale geologic map of any country covering 65,000 square miles. By far, it was the most accurate at its time and the basis for all others. Concealed behind stately green velvet curtains, it is on display in the foyer of the Geological Society of London’s Burlington House in Piccadilly alongside a bust of William. The Society is not to keen on allowing photographs of their geological masterpiece, so choose your moment carefully.
William Smith was born in 1769 in the hamlet of Churchill in Oxfordshire, the orphaned son of the village blacksmith. Raised by his uncle and with only a rudimentary education, he quickly learned the surveyor trade as an assistant. Fortuitously, he applied his skills with the Somersetshire Coal Canal Company, at which time he observed that rock layers within the canals were arranged in a predictable pattern and could always be found in the same relative positions. He also noted that each stratum was identifiable by the fossils that it contained and that the same succession of fossil groups from older to younger rocks could be found across the countryside, even as the layers dipped, rose and fell. In time, his astute observations led him to the hypothesis of the Principle of Faunal Succession – a major geological concept in determining the relative ages of rocks and strata.
Travelling throughout Britain, he observed exposures of the strata and meticulously sampled and catalogued their characteristics. First mapping vertically and then horizontally in color, his first sketch in 1801 led to the publication of the geological map of Britain. The timing was right. This was the dawn of the Industrial Revolution in England. Coal was king, and maps were needed. Yet, Smith's maps were plagiarized by the Geological Society of London, forcing him into bankruptcy and debtor’s prison. Destitute but not deterred after years of homelessness, Smith's bad fortune began to turn.
Over a decade later, he was eventually accepted into and honored by the Geological Society of London for his contributions as “the Father of English Geology.” In 1831, he was conferred the first Wollaston Medal by the Society in recognition of his achievements to the new science - all without a formal education in geology! It’s their greatest honor, bestowed by the very institution that denied him membership because of his low social status. Later, he was awarded an honorary doctorate of letters from Trinity College in Ireland. This uneducated surveyor rubbed elbows with famous astronomers, naturalists, biologists and geologists.
Simon Winchester in his book The Map That Changed the World summed up Smith's map as the work of a lonely genius. He states, "The task required patience, stoicism, the hide of an elephant, the strength of a thousand, and the stamina of an ox. It required a certain kind of vision, an uncanny ability to imagine a world possessed of an additional fourth dimension, a dimension that lurked beneath the purely visible surface phenomena of the length, breadth and height of the countryside, and, because it had never been seen, was ignored by all customary cartography. To see such a hidden dimension, to imagine and extrapolate it from the little evidence that could be found, required almost a magician's mind - as geologists who are good at this sort of thing know only too well today."
The brilliance of William Smith’s achievement is demonstrated by comparing the accuracy and detail of his maps with the ones used by the Geological Society today and the rest of the world. His creation heralded the beginning of a new science and anointed him as its founding father. As for Dr. William Smith, nothing but goodness, recognition and respect attended the final years of his life.
February
The Longitude Problem
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"The College will the whole world measure;
Which most impossible conclude,
And navigation make a pleasure
By finding out the longitude.
Every Tarpaulin shall then with ease
Sayle any ship to the Antipodes."
Anonymous (circa 1660) from the Ballad of Gresham College
On a foggy night in 1707, British Admiral Sir Cloudesley Shovell’s celebrated naval career was brought to a tragic end along with the lives of nearly 2,000 sailors, when his warship and three others in the fleet were wrecked on the rocks of the Isles of Scilly, off Great Britain's southwest coast. It was one of the greatest disasters at sea in British history and one of countless shipwrecks befallen to seafaring nations throughout history. The main cause of the British tragedy was the navigators’ inability to accurately determine their position at sea - longitude in particular. In response, Parliament established the Longitude Prize in 1714. The reward was for a "practical and useful" method for the precise determination of a ship’s longitude. The winner would collect £20,000 or roughly 4 million dollars in today’s currency, if accurate within half a degree (30 nautical miles at the equator). It was a large sum to pay for a desperate nation.
Back in school, we learned that our planet is divided into an imaginary grid. Hula hoop lines of latitude or parallels encircle it horizontally, the largest at the equator, while vertical, equi-length, pole-to-pole lines of longitude or meridians mark locations east or west of the Prime Meridian or 0º longitude. Unlike the equator, the Prime's location is arbitrary and is a universally-accepted reference line whose location has varied historically (Until 1911, the French used a Paris meridian). As of 1851, it runs through the Royal Observatory at Greenwich, England, which is located on a majestic hill overlooking the Thames River, where the above photo was taken looking north. The line is actually slightly to the right, but 500 happy kids were busy straddling the line with one foot in each hemisphere. Used together, latitude and longitude provide every location on our earthly sphere with a global address, and when calculated, indicate one’s whereabouts on a map – an important feat at sea when land is out of sight. If you know where you are, then you know where you're going. Admiral Shovell would surely have agreed.
One’s latitude is relatively easy to determine. Since ancient times, it was known that a star will consistently reach the same highest point in the sky, which changes with the observer’s latitude. By “sighting” the angle (declination) of the sun at it highest point from the horizon during the day or say the North Star at night, one’s position can be calculated from a table simply by knowing the time of measurement. On the other hand, finding longitude hasn't been so easy. Without it, ships at sea would follow a line of known latitude east or west, turn toward their assumed destination, and then continue on another line of known latitude. This process extended the voyage by days or weeks with increased risk of scurvy, bad weather, lack of potable water, starvation and worse - shipwreck. Another option was dead reckoning by using a predetermined “fix” and advancing that position based upon one’s known speed over time. Navigators threw a long, knotted rope attached to a log overboard and counted the number of knots let out in a given interval to allow a distance and speed calculation (which by the way is where we get the nautical term for speed at sea). The process was subject to cumulative errors induced by wind, current and change of course.
The longitude problem was viewed by astronomers as requiring a celestial calculation such as by viewing eclipses of Jupiter's moons or our own, which required extensive heavenly observations and complex charts - hence the observatory in Greenwich. Clockmakers, on the other hand, envisioned the problem as requiring a temporal calculation. As expected from such a large reward, there was a myriad of hair-brained solutions such as a fleet of globally-distributed anchored ships that fired position-signalling cannons as longitude locators.
Ultimately, it was John Harrison, a self-educated English carpenter and clockmaker, who, after over four decades of toil and experimentation, successfully invented a masterpiece of engineering. His H4 (earlier versions were H1 through H3) was a pendulum-less “sea clock” that was unaffected by movement and changes in temperature. At sea, a ship’s captain could, using Harrison’s marine chronometer, calculate longitude by comparing the time on his pocket watch to a constant clock at a predetermined location.
Here's how the the concept worked. The Earth makes a complete rotation on its axis every day. If there are 24 hours in a day, one hour of rotation is equivalent to 15º of rotation (360º ÷ 24). Thus, there exists a relationship between time and longitude. If you set your watch to 12:00 noon (not temporal noon but astronomical noon when the sun is highest in the sky at its zenith) at say Greenwich time, and you observe the sun at 4:00 PM at another location, then you’re at longitude 60º W (4 hours x 15º/hour = 60º). Finding local time was relatively easy. The problem was how to determine the time at a distant reference point while onboard a rocking, swaying, storm-tossed deck - an impossible task back in Cloudesley’s day with pendulum-swinging clocks that required a stable surface for accuracy.
Harrison's H4, which basically looks like an over-sized pocket watch, achieved all that and more - pendulum-less, compact, portable, shipworthy and accurate. Harrison's many timepieces are on display at the Royal Observatory, and as for their inventor, he spent his final years tinkering and experimenting with many timekeeping innovations - a very wealthy man.
February
Plaster of Paris Meets the Father of Comparative Anatomy
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Built of gleaming white travertine (a redepositional form of limestone), the Basilica of the Sacred Heart radically changed the profile of the once pastoral, hilltop village of Montmartre - located on the northern outskirts of Paris and now an integral part of the city. Beginning in 1875, its 39-year construction was no easy task, since its foundation was literally riddled with subterranean gypsum quarries.
Gypsum- an evaporite mineral formed by dehydration in an arid environment - is used in the manufacture of Plaster of Paris by heating it and then reapplying water to get it to harden. It has been excavated from beneath Montmartre from antiquity through the 19th century. Amongst its many decorative and artistic uses, it serves as an effective natural fire retardant on wooden structures, akin to our modern plaster board. After the Great Fire of London in 1666, its use was decreed by French King Louis XIV and literally saved Paris from the destructive fires that ravaged all major European capitals.
The gypsum of Montmartre and the limestone of northern France formed within the Paris Basin. It began as an epeiric (shallow inland) sea on the northeastern fringe of Laurentia (the cratonic core of ancestral North America) some 200 million years ago. When the supercontinent of Pangaea fragmented apart beginning in the Late Triassic, the basin (and the new continent of western Europe) was tectonically transported to the Eastern Hemisphere on the Eurasian plate across an ever widening Atlantic Ocean. Once part of northern France, the basin’s sedimentary rocks of limestone and gypsum were deposited some 45 million years ago during the Lutetian Period of the Eocene.
Outspoken critics of the Sacre Cour project - not only because of its exotic architecture but its exotic ideology - feared a seismic outcome related to its enormous weight. The architect, who had been commissioned to build his design, thought an immense platform of concrete four meters thick would stabilize the structure over the quarries. Instead, 80 stone pilings were laid down through the lime and clay and deeper through the voids of the quarries until bedrock was struck over 30 meters down. In effect, the foundation of Sacre Cour rests upon stilts like a dock on pilings over water. If an earthquake was to strike Montmartre, after the dust settled some Parisians thought the edifice would remain intact as if floating in air.
When you visit Paris or on Google Earth, you can catch a glimpse of the entrance to one the quarries beneath the basilica fenced off on the northern end of rue Ronsard. It was in these very gypsum quarries that the famous French naturalist and zoologist Georges Cuvier excavated Eocene mammalian fossils from the strata in the 1790’s. His investigations led him to the inescapable conclusion that fossils were the remains of animals long-extinct. A lifelong Protestant, he believed that periodic catastrophies had befallen the planet and its lifeforms. That implied God had allowed some of his creations to vanish, a rather blasphemous conclusion against the tenets of the English church and one of the foundations of modern paleontology. Cuvier's contributions and uncanny ability to reconstruct lifeforms from their fragmentary remains led to his appellation as the “Founder of Comparative Anatomy.”
March
The Seine's Epic Journey to the Sea
Four large rivers water France – the Loire, the Seine, the Rhine and the Rhone – linked by a system of interconnecting canals. The second longest is the Seine (pronounced SEN), which begins a 776 kilometer (482 mile) journey to the sea from a modest cluster of springs called the Source de Seine northwest of Dijon. This is the Cote d’Or, literally “golden slope” that arguably produces the best wines (and mustards) in the world. It’s the right combination of climate, soil, and of course, clean water.
The Seine flows through a thousand tiny hamlets, fields and woodlands, and halfway to the sea, right through the middle of Paris. It divides the city into its two famous banks - the conservative Left Bank or Rive Gauche and the radical Right Bank or Rive Droite. The Seine is the heart and soul of Paris, where the Parissi tribe first settled and where Romans took residence in their conquest of Gaul in 52 BC.
The Seine flows through an enormous geological depression flanked by huge escarpments that began to flood when it was part of an intricate network of inland seas when the Atlantic Ocean was just beginning to open. The supercontinent of Pangaea’s fragmentation sent the Paris Basin adrift on the Eurasian Plate across the Atlantic Ocean, along with a network of interconnecting basins in western Europe. Good thing for France. The River Seine is actually a recent waterform within the ancient trough, having originated when the Pleistocene ice sheet and enumerable alpine glaciers sent their waters to the sea from the highlands that encompass the basin.
Twenty-six tributaries later, the estuarine Seine discharges into the ocean, more precisely the English Channel, between the twinports of Honfleur and Havre, seen above through the clouds on my return flight from Paris to Boston.
May
Blue Skies, Green Water and Red Rocks on the Stove Pipe Trail
“The landscape everywhere, away from the river, is rock – cliffs of rock; tables of rock;
plateaus of rock; terraces of rock; crags of rock – ten thousand strangely carved forms."
John Wesley Powell, 1875
Originating in the Wind River Mountains of Wyoming and skirting the northwest corner of Colorado, the Green River flourishes in Utah in all its glory. It's a 730-mile long, chief tributary of the Colorado River before reaching their confluence at the southern terminus of the Island in the Sky. In northeast Utah, the Green carves its channel over and through fluvial and marine rocks of Cretaceous age - grayish remnants of a vast inland sea that connected then-warm Arctic waters with those of the Gulf of Mexico, yet to form. In southeast Utah, things change dramatically, as the river downcuts through rocks of Jurassic, Triassic, Permian and Pennsylvanian origins.
This is Canyonlands, where John Wesley Powell in 1869 surveyed, mapped, described and named the landforms on the first of two expeditions to the region. First, through curvy Labyrinth Canyon and then more linear Stillwater Canyon, both appropriately named, the Green River slices its way back in time through confining cliffs of the Jurassic Glen Canyon Group and underlying erodible slopes and ledges of Triassic Chinle and Moenkopi Formations. The strata of these two geologic periods of the Mesozoic tell a tale of widespread Jurassic aridity in western Pangaea and distant Triassic mountain ranges draining across vast floodplains and river systems to the sea.
Our journey down the Green River - under the leadership of famous geologist Wayne Ranney and the supreme navigational skills of Walker Mackay and his family-run Colorado River and Trail Expeditions or CRATE - rafted us into camp at the foot of the Stove Pipe Trail in Stillwater Canyon, about seven miles upriver from the confluence.
To work up an appetite for dinner, we ascended over 1,000 feet through a series of switchbacks and a palette of colors derived from cherty, chalky limestones and dolomites, pale-red sandstones, blue-gray siltstones and thin beds of evaporites of the Elephant Canyon Formation. At the top, where the photo was taken, the white to pale-reddish brown and salmon-colored Cedar Mesa Sandstone comes into view, forming the cliffs and ledges that hold it all up. These Permian strata are derived from the Ancestral Rocky Mountains or, more appropriately, the southwest range of the Uncompahgre Highlands that began their ascent in Pennsylvanian time. As they rose, the inexorable forces of erosion tore them down. Here too was an inland sea represented by the Uncompahgre's flexural trough that persisted with intermittent communications with the ocean and whose dimensions vacillated with the whim of South Polar glaciation an astounding 33 times. To see the strata within the trough, we had to wait for the following day in order to travel further down the Green.
Both long gone, the highlands and basin left their signature deposits from Colorado to Utah. Uplift and erosion of the Colorado Plateau have put the finishing touches on the landscape. What's left is a rainbow feast for the eyes!
June
Born to Reproduce
On a glorious Spring afternoon outside of Boston, I exited the train station and began the short walk home. A bright colored object on the ground caught my eye, and, glancing down, I spotted this splendid Cecropia Silkmoth (si-KROH-pee-uh) on the pavement. A little worse for wear, I photographed it with my cellphone. I recognized the creature, having remembered a pinned specimen from sixth grade biology class so long ago.
The cecropia is North America’s largest moth and are abundant east of the Rockies, although this specimen is the first I’ve seen outside of class. Females achieve a wingspan of seven inches! The larvae are mostly found largely on maple trees, which squirrels fastidiously dine on. I suspect this is a male, based on the more resplendent morphology of its antennae, having evolved as such for one specific purpose.
Born to reproduce, nocturnally-active males lack functional mouthparts and a digestive system, and therefore survive only a few weeks. Unable to resist, males fly miles following the scent plume of wind-born female pheromones, guided by their antennae. Using an adaptive process called chemical mimicry, bolas spiders copy the pheromones produced by cecropia females, in order to lure males into their next meal. Predators and their prey exist up and down the food chain at virtually every level.
July
Architectural Geology of Boston – the Oldest Cut Granite Building in America
"In the love of truth, and the spirit of Jesus Christ,
We unite for the worship of god and the service of man."
King's Chapel Covenant
King’s Chapel in Boston was designed by Peter Harrision of Rhode Island and built in 1754 on the site of a smaller wooden Anglican church, itself built in 1688. It was situated on the public burying ground, because no resident would sell land for a non-Calvinist church. The stone church was constructed around the wooden church, so that the parishioners could continue to practice their faith, and was later disassembled and removed through the windows of the new church.
The edifice is a classic example of American Georgian architecture – eponymous for the first three British monarchs of the House of Hanover, all named George in the early 18th and early 19th centuries. Its salient architectural features include a tall, boxy portico surrounded by 12 painted Ionic columns made of wood. The cornice has decorative mouldings and is topped off with a spindled-balustrade that terminates in a flat-roofed tower with four louvered, arched windows. The planned steeple was never built, which gives the church its distinctive "unfinished" look. Directly behind, the chapel has a characteristically four-sided, hipped roof. The Georgian style was big in eastern America, that is until King George III and the American Revolution turned the aesthetic sentiment elsewhere.
King’s Chapel was originally planned to be of English sandstone but was built with native Quincy Granite. It's the oldest, still-standing granite building in Boston but not the first to utilize granite, having been incorporated into many early foundations and associated structural elements. The blocks of granite demonstrate a patchwork color mix with pockmarked surfaces on the exposed “seam-faces.”
The granite's appearance is reflective of the mode of quarrying from boulders scattered about rather than from excavated bedrock. The process involved heating and splitting the granite with heavy iron balls, followed by hammering, chiseling and shaping into stackable units. The "quarry" locale was Quincy (pronounced KWIN-zee), about 10 miles south of Boston. The town is officially called the “City of Presidents” after John Adams and John Quincy Adams, but its nickname is the Granite City. A hundred years later, the use of famous Quincy Granite in construction would become commonplace in Boston, and quarrying the bedrock would become a major commercial enterprise there.
By the way, in the bowels of King's Chapel is a 200-year old crypt and in the tower is the largest and last bell made by Paul Revere. It's located on the famous Freedom Trail, the red brick line on the pavement in front of the chapel.
October
The Granite Railway
In the face of great opposition to his idea, architect and engineer Solomon Willard traipsed all across New England looking for the perfect stone. His plan, after several architectural modifications, was the construction of a 221-foot tall obelisk out of Quincy Granite - the Bunker Hill Monument - situated in Charlestown across the harbor from Boston. By comparison, the Washington Monument - built to commemorate George Washington - was completed in 1884 on the National Mall in Washington, DC, and is the world's tallest stone obelisk at 555 feet. Willard's edifice was built to commemorate the Battle of Bunker Hill, the first major conflict between the British Regulars and the Patriot forces of colonial militiamen in the Revolutionary War fought in 1775. Technically, the monument is not on Bunker Hill but on Breed’s Hill, where most of the fighting in the misnamed Battle of Bunker Hill actually took place.
In 1825, Willard recognized there was something special about the granite in the hills west of Quincy. It wasn’t its convenience, since the granite still had to be excavated - no easy or safe task back then. It wasn’t its proximity (although that helped), since a lot of varied terrain stood in the way of the granite’s final destination. And it wasn’t the granite’s massivity - not meaning lots of it (which there was) but referring to its consistent homogeneity for aesthetic purposes.
It was from Quincy Granite’s unique mineral composition. The high percentage of alkali feldspar, as opposed to the plagioclase variety, affords the rock its dusty gray, greenish tint, aided by its variety of black quartz. Formed from the slow crystallization of magma some 450 million years ago when the micro-terrane of Avalon was in transit to Laurentia, the granite’s characteristic mineral of riebeckite, a brittle prismatic amphibole, allows the rock to achieve a high polish, in addition to its lack of micas. Quincy Granite was the rock that Willard sought - attractive, distinctive, stately, transports well, available, highly polishable and weather-resistant.
It was from Quincy Granite’s unique mineral composition. The high percentage of alkali feldspar, as opposed to the plagioclase variety, affords the rock its dusty gray, greenish tint, aided by its variety of black quartz. Formed from the slow crystallization of magma some 450 million years ago when the micro-terrane of Avalon was in transit to Laurentia, the granite’s characteristic mineral of riebeckite, a brittle prismatic amphibole, allows the rock to achieve a high polish, in addition to its lack of micas. Quincy Granite was the rock that Willard sought - attractive, distinctive, stately, transports well, available, highly polishable and weather-resistant.
However, a major obstacle in 1826 was getting multi-ton blocks out of the ground, down from the heights above Quincy and across 12 miles of swamp, forest and farms for construction. After considering an overland route, the solution of how to transport the blocks from the quarry to a dock on the Neponsett River was modeled after English railroads. The idea for the Granite Railway was conceived and became not the first public transportation railroad in the United States but the first purpose-built, commercial railroad.
It ran only three miles with wagons pulled by horses, although steam locomotives had been in operation in England for two decades. Wooden and later granite rails on stone crossties were plated with iron. In 1830, a new section of railway called the Incline, seen above, was added to haul granite from the quarry, one of many above town. Wagons and horses moved up and down the 315 foot incline in an endless conveyor belt. From the docks, blocks were loaded on barges that traveled across Boston Harbor. Off-loaded onto ox-drawn carts, the cargo went up a hill at Charlestown for construction of the obelisk. The capstone was laid in 1842 at a project cost of $101,680. Interestingly, the monument underwent a 3.7 million dollar renovation in 2007 - the cost of 36 monuments!
The Incline remained in operation until the 1940’s with metal channels laid over the old granite rails and motor trucks pulled by a cable. In 1871, steam trains carried the granite directly to Boston from the quarries.
These days, the quarries have been filled in for safety purposes with 12 million tons of dirt from the Big Dig highway project in Boston. In years past, many young persons were injured or killed while swimming and cliff diving into the abandoned quarries that had filled with water. Ironically, the steep quarry walls are used today by organized groups of rock climbers to hone their skills. As for the Granite Railway, it's listed on the U.S. National Register of Historic Places, while the Bunker Hill Monument towers over Charlestown across the harbor from Boston proper. You could see it from the quarry, if it wasn’t for the city's tall buildings. The Bunker Hill Monument is managed by the National Park Service and is on Boston’s Freedom Trail.
November
The Bridge that Spans Two Geologic Eras
Viewed from Upper Manhattan, the George Washington Bridge spans the Hudson River between New York and New Jersey. Its footings are secured in two geologic eras. Cross the bridge heading west, and you time-travel from the Late Proterozoic to the Paleozoic. During the Late Triassic, the supercontinent of Pangaea began its fragmentation and newly-evolving dinosaurs were trudging through the mudflats of the Jersey Meadowlands. That epic schism created the continents of our New World and the Atlantic Ocean within the void, while the North American and Eurasian tectonic plates continue to drift apart.
During supercontinental breakup, aborted rift basins from the Canadian Maritimes to Georgia developed up and down the margin of North America. In northeastern New Jersey and southeastern New York, the Newark rift basin subsided and listrically tilted as molten mafic rocks injected through the depocenter’s sedimentary strata into black argillites of the Lockatung Formation. The prominent cliff seen above on the western bank of the Hudson represents the eroded edge of that angulated, tabular intrusive sheet – the famed Hudson River Palisades. Its obvious vertical jointing formed when the magma solidified, so spectacularly exposed by the carving of the Hudson Canyon during the last Ice Age.
The Palisades was threatened by quarrying in the early 20th century, when J.P. Morgan, American financier, banker, philanthropist and art collector, purchased twelve miles of New Jersey shoreline. On the east side of the river in Washington Heights, John D. Rockefeller, American business magnate and philanthropist, acquired the land of Fort Tyron and the Cloisters, where this photo was taken.
Thankfully, the natural beauty of the Palisades cliffs rising above the west bank of the Hudson has long been appreciated by generations of residents and visitors to the metropolitan area. But now, LG Electronics, a South Korean multinational electronics corporation, is planning to build an office tower that will rise high above the trees, and for the first time, violate the unspoiled ridgeline. Interested in preserving the Hudson River Palisades? Visit “Protect the Palisades” here.
Thankfully, the natural beauty of the Palisades cliffs rising above the west bank of the Hudson has long been appreciated by generations of residents and visitors to the metropolitan area. But now, LG Electronics, a South Korean multinational electronics corporation, is planning to build an office tower that will rise high above the trees, and for the first time, violate the unspoiled ridgeline. Interested in preserving the Hudson River Palisades? Visit “Protect the Palisades” here.
That's all folks. Thanks for following my blog! Happy New Year!
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