Posts Tagged 'Geology'

Fossils

A collection of fossils from Missouri, from back when the region was a shallow sea. Long before our time, my friends. These were a gift from a friend who recommended they be boiled a long, long time before they’re ready.

I can’t get over the ones that look like liberty or Phrygian caps. You might be more familiar with those from the French Revolution, but Americans wore them first. Mineralization: turned to stone.

Oh, Schist!

The eastern edge of Twin Island, facing Long Island Sound just north of Orchard Beach in the Bronx, is an outcropping of the Hartland Formation schist.And does it ever outcrop!Quoting the geological argot of the USGS “The rock consists of granitic and garnetiferous amphibolite gneiss with numerous quartz veins and migmatite dikes. Migmatite is an type igneous rock that forms when metamorphic rocks begin to melt under high temperature. Felsic minerals melt and are injected into the surrounding rock along joints, faults, and other zones of weakness in the rock. As the igneous material gradually cools, bands of feldspar and quartz crystals form along the edges of the intrusion. The center of the migmatite veins typically consist of larger crystals of feldspar and quartz. The migmatite stands out in outcrops as light-colored bands in contrast to the darker amphibolite gneiss host rock. In some cases, the dikes cut across older dikes and quartz-filled veins; many are folded or display offset by faulting.” It’s an open-air classroom, so here’s Hunter College on the spot: “The site contains the following rock types: gneiss, amphibolite, migmatite, pegmatite, quartz veins, marble, ptygmatic folds, pearl gneiss, and boudines. The following minerals can be found here: K-feldspar, quartz, biotite, muscovite, hornblende, garnet, pyrite, limonite, kaolinite, calcite, tourmaline, plagioclase, and chlorite.” .I’ll say that again!

Gorges

“Ithaca is Gorges” is awfully good branding. I thought the gorges that sliced away through shales and sandstones at the northern and southern edges of Cornell were gorgeous.Fall Creek in the rain during the morning. Most of this one is seen from above, on the Cayuga Trail. Only disconcerting thing: all the anti-suicide netting on the bridges.
Cascadilla Gorge in the late afternoon, after the sun had come out. We descended to town from the hill citadel of the university, right alongside the tumbling water.

Flinty

The National Museum of Copenhagen is filled with flint tools from the pre-metal millennia. This stuff makes for very sharp edges. The stone of Europe’s Stone Age, flint stones were also used to start fires and spark guns into the 19th century. The Baltic beaches were littered with nodules of this dark chert. It’s a finely-grained quartz, not, as I first thought, obsidian (which is volcanic glass). This fist-sized and rather knuckle-like piece was my Swedish souvenir, found on a beach in Malmo. Here’s the verso and recto of a piece I split on the Northumberland coast a few years ago when my dearheart said the original piece was too large to carry back on the plane.The white coating here is typical. According to this site, “The thick white crust, the cortex, is not made of chalk, but of fine-grained opaline silica.”

Chesapecten

These are fossilized shells of extinct scallops found on the Piankatank River in Virginia. They’re in the genus Chesapecten, all of whose members no longer live upon this earth. Such mineralized remains are dated from the early Miocene period to the early Pleistocene.

Here’s more detail about the rich fossil world of the Chesapeake.

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Trump yearns for an FBI to go after journalists. Secretary of Corruption (formerly Commerce) Wilbur Ross praises the lack of protests in the dictatorship of Saudi Arabia. A reporter was arrested when he tried to question Secretary of Death (formerly Health) Tom Price. Meanwhile, the Trump regime has been rather shameless about Turkish gestapo tactics in the heart of Washington D.C., because pretty clearly they want to be able to emulate them. After all, they cite the murderous kleptocracy of Putin’s Russia as a model.

Those who are against our best traditions are not patriots. They are, in fact, traitors. Never, ever, let supporters of Trump get away with claims of patriotism again.

Oregonia

mushroom

caterpillar

bark

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There’s your beautiful world, NW edition. Here’s Masha Gessen, an old hand at autocracy, on surviving Trumpism, very necessary reading now.

Traces of the Ice Age

striationsDon’t you just love these? These grooves are found along the path in the forest of the NYBG, and time and generations of feet have worn them down slightly. They’re glacial striations, gouged out by the rubble on the bottom the ice as it scraped across the hard surface rock.

These can be found in Central Park, too. But not here in the home borough, which is all glacial deposit–made up, come to think of it, with some of that Bronx rock.


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