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The American Niagara Falls without water (New York, 1969).

The American Falls is the second of three waterfalls that make up the Niagara Falls.  It has a massive talus (rock pile) at its base as a result of a series of natural rockslides in 1931 and 1954.  In the late 1960s, however, there were concerns that further rockslides could erode the falls entirely.  A joint American-Canadian commission decided to “dewater” the falls for five months, so that a geological survey of the rock face could be carried out.

So in June 1969, over 1,200 trucks dumped nearly 28,000 tons of rocky fill into a dam upstream of the falls [1 top right & 2], diverting the flow of the Niagara River away from the American Falls and towards the much larger Horseshoe Falls.  This process took three days.  The US Army Corps of Engineers could then begin their investigation.

The riverbed was criss-crossed with a series of cracks [4] that were examined for possible links to rockslides, and the engineers mechanically bolted and strengthened any faults that they found [7]. They drilled test-cores to check for instabilities, planted instruments to monitor rock movements in several locations, installed steel bolts and cables to stabilize the rocks around Luna Island and Bridal Veil Falls, and drilled drainage holes to relieve hydrostatic pressure at several points.

A temporary walkway was installed 6 metres from the edge of the dry falls, allowing tourists to explore the landscape.  Only two corpses were found during these five months, which was surprising given the falls’ history of accidents and suicides.

There was a plan to remove the huge mound of talus [9], but it was abandoned because of the high cost for what would be basically aesthetic reasons.

In November, the dam was dynamited in front of 2,650 observers, restoring the river’s flow to the American Falls.  Luna Island (between the American and Bridal Veil Falls) remained off-limits to the public for years, due to fears that it was unstable and could collapse into the gorge.  Erosion of the American Falls used to be about 1.2m a year, but today it is only 7.5 – 10.0cm.

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Mount Rainier from Crystal mountain [OC][2592x3888]

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The Most Photographed Stone East of the Mississippi

Very near the Soudan Underground State Park administered by the Minnesota Department of Natural Resources is what some people call “the most photographed outcrop in the state.” This is a pavement outcrop of folded banded iron formation. The outcrop consists of metallic hematite, red jasper and white chert. These originally horizontal layers have been folded multiple times. In some areas, the jasper and chert have fractures filled with milky quartz.

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Garnet var. Uvarovite

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This new Hubble image shows spiral galaxy ESO 137-001, framed against a bright background as it moves through the heart of galaxy cluster Abell 3627. This cluster is violently ripping the spiral’s entrails out into space, leaving bright blue streaks as telltale clues to this cosmic crime. This new Hubble image shows ESO 137-001, a galaxy located in the southern constellation of Triangulum Australe (The Southern Triangle) — a delicate and beautiful spiral galaxy, but with a secret. This image not only captures the galaxy and its backdrop in stunning detail, but also something more dramatic — intense blue streaks streaming outwards from the galaxy, seen shining brightly in ultraviolet light. These streaks are actually hot young stars, encased in wispy streams of gas that are being torn away from the galaxy by its surroundings as it moves through space. This violent galactic disrobing is due to a process known as ram pressure stripping — a drag force felt by an object moving through a fluid. The fluid in question here is superheated gas, which lurks at the centres of galaxy clusters. This image also shows other telltale signs of this process, such as the curved appearance of the disc of gas and dust — a result of the forces exerted by the heated gas. The cluster’s drag may be strong enough to bend ESO 137-001, but in this cosmic tug-of-war the galaxy’s gravitational pull is strong enough to hold on to the majority of its dust — although some brown streaks of dust displaced by the stripping are visible. Studying ram pressure stripping helps astronomers to better understand the mechanisms that drive the evolution of galaxies. For example, it will leave this galaxy with very little of the cold gas that is essential for star formation, rendering the galaxy effectively incapable of forming new stars. Caption: Hubble Heritage Team NASA, ESA, D. JEWITT (UCLA)

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Azurite with Cerussite and Arsentsumebite - Tsumeb Mine, Tsumeb, Otjikoto Region, Namibia, Africa.

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Fluorite

Okorusu Mine, Otjiwarongo Region, Karibib District, Namibia

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Planetary Scientists Create Global Geologic Map of Ganymede http://www.sci-news.com/space/science-geologic-map-ganymede-01759.html

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CINNABAR (Mercury Sulfide) from Guizhou Province, China. The photo shows crimson red cinnabar crystals associated with quartz and calcite. Microscope photo taken at 10X. 

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Rutile Quartz cluster

Thailand

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CHALCANTHITE (Copper Sulfate) crystals that were grown in a laboratory by allowing a saturated solution of copper sulfate to slowly evaporate. The beautiful electric blue colour is typical of laboratory grown chalcanthite crystals. The crystals provide a stunning view under a binocular microscope. Photo taken at 15X with a binocular microscope.

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copper sulfate crystals, grown by solution evaporation

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Deceased Researcher’s Message In A Bottle Discovered In The Arctic

The message is dated July 10, 1959.

In the northernmost reaches of the Canadian Arctic, 500 miles (800 kilometers) away from the nearest human settlement, researchers discovered a literal message in a bottle, Halifax’s Herald News reports.

It begins just like the worst examples of cover letters on the Internet: “TO WHOM IT MAY CONCERN.” But the rest of it is pretty awesome. It turns out it’s a note buried by Paul Walker, an American geologist well known to those in his field today. He built two rock “cairns” in this remote spot, as the discovering scientist, Warwick Vincent of Laval University in Quebec, described them. Walker asks scientists of the future to measure the distance between the two cairns, one of which is located on the Ward Hunt ice shelf. Walker wanted to know whether the ice shelf, the Artic’s largest, was growing or retreating.

The note is dated July 10, 1959. Vincent and his colleagues carried out Walker’s request and discovered that the rock piles are now 333 feet (101.5 meters) apart. In Walker’s day, the distance was just 4 feet. The findings jibe with Vincent’s work tracking the melting of the ice here, theHerald News reports.

Sadly, Walker, 25, died the same year he set up this 54-year-long experiment. He had a stroke while out in the Arctic, the Los Angeles Times reports. A bush pilot came to bring him back to civilization and to medical care, but he died in his parents’ home that November.

source 

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 Aquamarine with Cleavelandite and Muscovite

Shigar Valley, Skardu District, Baltistan, Northern Areas, Pakistan

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Martian TARs (Traverse Aeolian Ridges), an overview by Dr. Jim Zimbelman of the Smithsonan National Air and Space Museum

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Temperature and Current of Earth’s Oceans, recorded by the Goddard Space Center

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Selenite gypsum