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Posts Tagged ‘geology

“On the geological time scale, a human lifetime is reduced to a brevity that is too inhibiting to think about deep time”*…

 

new geological era

The official history of Earth has a new chapter – and we are in it.

Geologists have classified the last 4,200 years as being a distinct age in the story of our planet.

They are calling it the Meghalayan Age, the onset of which was marked by a mega-drought that crushed a number of civilisations worldwide.

The International Chronostratigraphic Chart, the famous diagram depicting the timeline for Earth’s history (seen on many classroom walls) will be updated [as above]…

More at “Welcome to the Meghalayan Age – a new phase in history.”

But lest one think that a move like this is without controversy, consider this professional reaction:

“What the fuck is the Meghalayan?” asked Ben van der Pluijm, a geologist.

Whatever the Meghalayan is, we live in it now…

More at “Geology’s Timekeepers Are Feuding.”

* John McPhee

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As we take sides, we might recall that it was exactly 75 years ago today, on this date in 1943, that Los Angeles had it’s first major attack of smog:

On July 26, 1943 a “gas attack” hit the city of Los Angeles.

Here’s how Chip Jacobs and William J. Kelly described this dark day in Angeleno history in the first line of their essential book, “Smogtown“: “The beast you couldn’t stab fanned its poison across the waking downtown.” The “beast” was smog…  [source]

smoggy-civic-center

The L.A. Civic Center in a 40’s smog cloud

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Written by LW

July 26, 2018 at 1:01 am

“South America must have lain alongside Africa and formed a unified block which was split in two in the Cretaceous; the two parts must then have become increasingly separated over a period of millions of years like pieces of a cracked ice floe in water”*…

Earth, 600 million years ago. The Ediacaran Period; life is evolving in the sea, and multicellular life is just beginning to emerge.

From the good folks who brought you Dinosaur Pictures, a chance to watch continental drift at work– a marvelous interactive model of the earth that you can view from the present to 600 million years ago: Ancient Earth.

* Arthur Wegener

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As we marvel at the evolving reality of nature, we might marvel as well at the laws that govern it: it was on this date in 1686, the publication of Newton’s Principia (the Philosophiae Naturalis Principia Mathematicawas arranged in London at the Royal Society. The minutes of the meeting record that the astronomer Edmond Halley would “undertake the business of looking after it and printing it at his own charge.”

Title page of the first edition

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Written by LW

June 2, 2018 at 1:01 am

“Wonder is the beginning of wisdom”*…

 

Depiction of a Dragon featured in Mundus Subterraneus

Just before Robert Hooke’s rightly famous microscopic observations of everything from the “Edges of Rasors” to “Vine mites” appeared in Micrographia in 1665, the insatiably curious and incredibly prolific Jesuit scholar Athanasius Kircher [see here] published what is in many ways a more spectacular work. Mundus Subterraneus  (Underground world), a two-volume tome of atlas-like dimensions, was intended to lay out “before the eyes of the curious reader all that is rare, exotic, and portentous contained in the fecund womb of Nature.” There is an “idea of the earthly sphere that exists in the divine mind,” Kircher proclaimed, and in this book, one of more than thirty on almost as many subjects that he published during his lifetime, he tried to prove that he had grasped it.

As a French writer put it some years later, “it would take a whole journal to indicate everything remarkable in this work.” There were extended treatments on the spontaneous generation of living animals from non-living matter, the unethical means by which alchemists pretended to change base metals into gold, and the apparent tricks of nature we now recognize as fossils. The book included detailed charts of “secret” oceanic motions, or currents, among the first ever published. The author’s more or less correct explanation of how igneous rock is formed was also arguably the first in print. According to one modern scholar, Kircher “understood erosion,” and his entries “on the quality and use of sand” and his “investigations into the tending of fields” had their practical use.

Mundus Subterraneus identified the location of the legendary lost island of Atlantis (something that modern science hasn’t been able to accomplish) as well as the source of the Nile: it started in the “Mountains of the Moon,” then ran northward through “Guix,” “Sorgola,” and “Alata” and on into “Bagamidi” before reaching Ethiopia and Egypt. Kircher offered a lengthy discussion of people who lived in caves (their societies and their economy). He reported on the remains of giants (also mainly cave dwellers) found in the ground. And he went into detail on the kinds of lower animals who belong to the lower world (including dragons).

In short, Mundus Subterraneus covered almost every subject that might relate to the realm of earth, as well as many that wouldn’t seem to, such as the sun and “its special properties, by which it flows into the earthly world” and the “nature of the lunar body and its effects.” These correspondences and influences were nothing new, though perhaps only the always-inclusive Athanasius Kircher would choose to publish a series of moon maps in a book about the world below…

Portrait of Kircher at age 53 from Mundus Subterraneus

More on this extraordinary work– inspired in part by a subterranean adventure Kircher himself made into the bowl of Vesuvius– at John Glassie‘s “Athanasius, Underground“; browse the book at the Internet Archive.

* Socrates

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As we praise polymathy, we might recall that it was on this date in 1804 that Corps of Discovery– better known today as the Lewis and Clark Expedition– left Camp Dubois, near Wood River, Illinois, commencing what would be a trek over two years on which they became the first American expedition to cross what is now the western portion of the United States.

President Thomas Jefferson had commissioned the expedition shortly after the Louisiana Purchase (in 1803) to explore and to map the newly acquired territory, to find a practical route across the western half of the continent– a Northwest Passage– and to establish an American presence in this territory before Britain and other European powers tried to claim it.

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Meriwether Lewis and William Clark

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“In a scientific pursuit there is continual food for discovery and wonder”*…

 

An ancient bear skull sits on the floor of Hoyo Negro, a flooded cave on Mexico’s Yucatán Peninsula

Some 13,000 years ago in what’s now the Yucatán Peninsula, a deep pit inside a cave became the final resting place for a menagerie of exotic animals.

Now, their exquisitely preserved bones, trapped for centuries under water, are offering some of the first solid clues to how large Ice Age beasts were mixing and migrating between North and South America after the Isthmus of Panama connected the two continents.

“We’re going to go from a place with no records to having the best records for a lot of megafauna from Mexico, Central America, and northern South America,” says East Tennessee State University’s Blaine Schubert, who presented the findings this week at the Society of Vertebrate Paleontology’s annual meeting in Calgary.

The animal bones are also painting a more detailed picture of the strange world inhabited by Naia, an Ice Age girl found in the cave who is the oldest, most complete human skeleton yet discovered in the Americas…

A remarkable discovery sheds new light on the exchange of life that occurred when the Isthmus of Panama rose from the ocean to connect two continents that had been ecologically separate for tens of millions of years: “Ice Age Predators Found Alongside Oldest Human in Americas.”

* “In other studies you go as far as other have gone before you, and there is nothing more to know; but in a scientific pursuit there is continual food for discovery and wonder.”   – Mary Wollstonecraft Shelley, Frankenstein

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As we re-trim our family trees, we might send illuminating birthday greetings to Ferdinand Vandeveer Hayden; he was born on this date in 1829.  Trained as a physician (who served with the Union Army during the Civil War), Hayden was a practicing geologist and paleontologist noted for his work in the Badlands in the mid 19th century– it is believed he made the first North American discovery of dinosaur remains (1854)– and for his pioneering surveying expeditions of the Rocky Mountains later in that century, which helped lay the foundation of the U.S. Geological Survey.  Hayden is credited with having the Yellowstone geyser area declared the first national park (1872).

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Written by LW

September 7, 2017 at 1:01 am

“To see a world on a grain of sand”*…

 

Sand covers so much of the earth’s surface that shipping it across borders—even uncontested ones—seems extreme. But sand isn’t just sand, it turns out. In the industrial world, it’s “aggregate,” a category that includes gravel, crushed stone, and various recycled materials. Natural aggregate is the world’s second most heavily exploited natural resource, after water, and for many uses the right kind is scarce or inaccessible. In 2014, the United Nations Environment Programme published a report titled “Sand, Rarer Than One Thinks,” which concluded that the mining of sand and gravel “greatly exceeds natural renewal rates” and that “the amount being mined is increasing exponentially, mainly as a result of rapid economic growth in Asia.”…

It’s one of our most widely used natural resources, but it’s scarcer than you think: “The world is running out of sand.”

* William Blake

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As we think anxiously about the beach, we might spare a thought for René Just Haüy; he died on this date in 1822.  An ordained priest (and honorary canon of Notre Dame), he began his scientific career as a botanist, but detoured into geology when a specimen of calcareous spar caught his fancy.  It inspired him to undertake a series of experiments which resulted in his outlining of the geometrical law of crystallization now associated with his name.  As a result, he’s considered the Father of Crystallography…  a field that concerns itself with quartz, a major component of sand.

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Written by LW

June 1, 2017 at 1:01 am

“Plato intended to write a long fable about legendary Atlantis; like Solon, he never did write it. Yet there existed beyond the Atlantic an unvisited land, after all”*…

 

The lost continent of Mauritia likely spanned a great swathe of the Indian Ocean before it was torn apart by indomitable geologic forces and plunged into the sea. Now, a good chunk of it may have been found.

In 2015, researchers visited the island of Mauritius, east of Madagascar, to study volcanic rocks. While there, they unearthed something unexpected. Embedded in the rocks were ancient crystals, dated up to three billion years old—300 times older than the island’s young volcanic surface. Rocks this old come from Earth’s continents, but there aren’t any continents around Mauritius. It’s surrounded by boundless sea in all directions. There was just one place left for the researchers to look—down. Their findings, published in the journal Nature Communications, suggest that the curious crystals came from a long-forgotten place buried well beneath the island…

Plumb the depths of Earth’s history at “Scientists may actually have found a lost continent.”  See also here (from whence, the illustration above)

* Russell Kirk

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As we take tectonics into account, we might spare a thought for René Descartes, the French philosopher and mathematician who thought and therefore was; he died on this date in 1650.

Many contemporaries (perhaps most notably, Pascal) rejected his famous conclusion, the dualist separation of mind and body; more (Voltaire, et al.), since.  But Descartes’ emphasis on method and analysis, his disciplined integration of philosophy and physical science, his insistence on the importance of consciousness in epistemology, and perhaps most fundamentally, his the questioning of tradition and authority had a transformative– and lasting– effect on Western thought, and has earned him the “title” of Father of Modern Philosophy.

“In order to improve the mind, we ought less to learn than to contemplate.”
– Rene Descartes

Frans Hals’ portrait of Descartes, c. 1649

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Written by LW

February 11, 2017 at 1:01 am

“The metabolic rate of geology is too slow for us to perceive it”*…

 

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Researchers modeled continental drift, going back 240 million years ago, on the scale of millimeters per year. It starts really slow and as if the supports give way to the separating pressure, there’s a relative burst of movement.

The full paper is in Nature, and the interactive version, which is a bit rough around the edges, can be found here. Select the time, rotate the planet around, and press play to watch the continents break apart.

From Flowing Data: “Continental drift, from 240 million years ago to present.”

(While the changes are slow, they are in fact detectable in the course of a human life; c.f., “Australia’s Entire GPS Navigation is Off By 5 Feet.”)

* Russell Banks, Continental Drift

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As we slip and slide, we might spare a thought for William Buckland; he died on this date in 1856.  A English theologian who became Dean of Westminster, he was also a paleontologist (who wrote the first full account of a fossil dinosaur, which he named Megalosaurus) and a geologist (who was known for his effort to reconcile geological discoveries with the Bible and anti-evolutionary theories).  A gentleman of some eccentricity, Buckland undertook his field work wearing an academic gown.

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Written by LW

August 15, 2016 at 1:01 am

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