What Causes Brazil’s ‘Meeting of the Waters’?
by Bec Crew
This is what it looks like when the Solimões River meets the Rio Negro in Brazil.
Almost 10 kilometres from the inland city of Manaus in northern Brazil, ‘the Meeting of the Waters’ is the point where two of Amazon River’s largest tributaries - a smaller river that flows into a bigger ‘parent’ river - converge but never mix.
The Solimões River forms the lighter half, its ‘cafe au lait’ colouring owed to the rich sediment that runs down from the Andes Mountains, including sand, mud and silt. Known as a ‘white water river’, the Solimões River stretches over a 1600 km distance. 
The darker side is the Rio Negro, and it gets its ‘black tea’ hue from leaf and plant matter that has decayed and dissolved in the water. It might look dark and murky, but the Rio Negro carries little or no sediment, and according to the European Space Agency website, is considered one of the cleanest natural waters in the world. On really clear days, water visibility in this black water river can exceed nine metres. ..
(read more: Science Alert - Australia)
Image: Danocoo1/Reddit.com

What Causes Brazil’s ‘Meeting of the Waters’?

by Bec Crew

This is what it looks like when the Solimões River meets the Rio Negro in Brazil.

Almost 10 kilometres from the inland city of Manaus in northern Brazil, ‘the Meeting of the Waters’ is the point where two of Amazon River’s largest tributaries - a smaller river that flows into a bigger ‘parent’ river - converge but never mix.

The Solimões River forms the lighter half, its ‘cafe au lait’ colouring owed to the rich sediment that runs down from the Andes Mountains, including sand, mud and silt. Known as a ‘white water river’, the Solimões River stretches over a 1600 km distance. 

The darker side is the Rio Negro, and it gets its ‘black tea’ hue from leaf and plant matter that has decayed and dissolved in the water. It might look dark and murky, but the Rio Negro carries little or no sediment, and according to the European Space Agency website, is considered one of the cleanest natural waters in the world. On really clear days, water visibility in this black water river can exceed nine metres. ..

(read more: Science Alert - Australia)

Image: Danocoo1/Reddit.com

Journey to the Center of the Earth 
by David Schneider 
Since the advent of plate tectonic theory in the 1960s, geologists have recognized that that many parts of the earth’s crust and mantle move horizontally. But most of that motion is exceedingly sluggish: usually less than 10 centimeters a year, which would barely outpace a growing fingernail.
Four years ago, seismologists Xiaodong Song and Paul Richards (both then at Columbia University’s Lamont-Doherty Earth Observatory) discovered that one part of the solid earth—the inner core—moves quite a bit faster, rotating in such a way that much of its surface shifts more than 10 kilometers a year. Such breakneck speed is possible because the inner core floats within a immense liquid shell…
(read more: American Scientist)
image: Kelvinsong

Journey to the Center of the Earth 

by David Schneider 

Since the advent of plate tectonic theory in the 1960s, geologists have recognized that that many parts of the earth’s crust and mantle move horizontally. But most of that motion is exceedingly sluggish: usually less than 10 centimeters a year, which would barely outpace a growing fingernail.

Four years ago, seismologists Xiaodong Song and Paul Richards (both then at Columbia University’s Lamont-Doherty Earth Observatory) discovered that one part of the solid earth—the inner core—moves quite a bit faster, rotating in such a way that much of its surface shifts more than 10 kilometers a year. Such breakneck speed is possible because the inner core floats within a immense liquid shell…

(read more: American Scientist)

image: Kelvinsong

Marianas Trench: The Deepest Depths
by Becky Oskin
The Mariana Trench is a crescent-shaped trench in the Western Pacific, just east of the Mariana Islands near Guam. The region surrounding the trench is noteworthy for many unique environments. The Mariana Trench contains the deepest known points on (the surface of the) Earth, vents bubbling up liquid sulfur and carbon dioxide, active mud volcanoes and marine life adapted to pressures 1,000 times that at sea level. 
The Challenger Deep, in the southern end of the Mariana Trench (sometimes called the Marianas Trench), is the deepest spot in the ocean. Its depth is difficult to measure from the surface, but modern estimates vary by less than 1,000 feet (305 meters). 
In 2010, the Challenger Deep was pegged at 36,070 feet (10,994 m), as measured with sounds pulses sent through the ocean during a 2010 survey by the National Oceanic and Atmospheric Administration (NOAA)…
(read more: Live Science)
image: NASA/UNH Center for Coastal and Ocean Mapping/Joint Hydrographic Center

Marianas Trench: The Deepest Depths

by Becky Oskin

The Mariana Trench is a crescent-shaped trench in the Western Pacific, just east of the Mariana Islands near Guam. The region surrounding the trench is noteworthy for many unique environments. The Mariana Trench contains the deepest known points on (the surface of the) Earth, vents bubbling up liquid sulfur and carbon dioxide, active mud volcanoes and marine life adapted to pressures 1,000 times that at sea level. 

The Challenger Deep, in the southern end of the Mariana Trench (sometimes called the Marianas Trench), is the deepest spot in the ocean. Its depth is difficult to measure from the surface, but modern estimates vary by less than 1,000 feet (305 meters). 

In 2010, the Challenger Deep was pegged at 36,070 feet (10,994 m), as measured with sounds pulses sent through the ocean during a 2010 survey by the National Oceanic and Atmospheric Administration (NOAA)…

(read more: Live Science)

image: NASA/UNH Center for Coastal and Ocean Mapping/Joint Hydrographic Center

Giant Icebergs Used to Ram Up Against Florida
21,000 years ago, icebergs carved up the ocean floor off the Miami coast
by Rachel Nuwer

Gaze out to sea from Florida’s beaches circa 21,000 years ago, and you would have spotted not paragliders and sailboats on the horizon but icebergs. According to a new study, icebergs from the Hudson Bay’s Laurentide ice sheet—a massive sheet of ice that all but covered Canada—broke free and drifted down the eastern coast of the landmass that would one day become America. 
Sometimes those icebergs would make it as far south as Miami and the Bahamas. Those giant hunks of ice—some of them up to 1,000 feet thick—left deep gouges along the Florida coast that can still be measured today...
(read more: Smithsonian Magazine)
image by Matthias Kulka/Corbis

Giant Icebergs Used to Ram Up Against Florida

21,000 years ago, icebergs carved up the ocean floor off the Miami coast

by Rachel Nuwer

Gaze out to sea from Florida’s beaches circa 21,000 years ago, and you would have spotted not paragliders and sailboats on the horizon but icebergs. According to a new study, icebergs from the Hudson Bay’s Laurentide ice sheet—a massive sheet of ice that all but covered Canada—broke free and drifted down the eastern coast of the landmass that would one day become America. 

Sometimes those icebergs would make it as far south as Miami and the Bahamas. Those giant hunks of ice—some of them up to 1,000 feet thick—left deep gouges along the Florida coast that can still be measured today...

(read more: Smithsonian Magazine)

image by Matthias Kulka/Corbis

libutron
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Fingal’s Cave | ©Darby Sawchuk (Staffa island, Scotland)
Staffa is the stuff of legend, an unspoilt and uninhabited island in the Inner Hebrides of Scotland, best known for its magnificent basalt columns and spectacular sea caves.
The most famous of these is Fingal’s Cave, also known as An Uamh Binn (Cave of Melody). It has a unique, cathedral-like structure and its hexagonal columns are similar to those of the Giant’s Causeway in Ireland.
Fingal’s Cave was immortalized by Mendelssohn in his Hebrides Overture, after he visited the island in 1829, and in a famous painting by the artist J M W Turner.
Reference: [1]

libutron:

Fingal’s Cave | ©Darby Sawchuk (Staffa island, Scotland)

Staffa is the stuff of legend, an unspoilt and uninhabited island in the Inner Hebrides of Scotland, best known for its magnificent basalt columns and spectacular sea caves.

The most famous of these is Fingal’s Cave, also known as An Uamh Binn (Cave of Melody). It has a unique, cathedral-like structure and its hexagonal columns are similar to those of the Giant’s Causeway in Ireland.

Fingal’s Cave was immortalized by Mendelssohn in his Hebrides Overture, after he visited the island in 1829, and in a famous painting by the artist J M W Turner.

Reference: [1]

Astrophile:  Tour the Lava Lakes of Io
by Jacob Aron
Take a trip to Io, one of Jupiter’s many moons, and you will find pools of boiling hot lava nestled among the erupting peaks of raging volcanoes. Welcome to the Lake District from hell.
Now researchers have pored over snapshots taken by a passing space probe to make freshly detailed descriptions of three of Io’s infamous hotspots: Pillan, Wayland Patera and Loki Patera.
They found that each one has its own unique eruption style. The work not only helps flesh out our understanding of the dynamics of this malevolent moon, but could also offer a glimpse of what the early, highly volcanic Earth was like.
Io traces an oval-shaped orbit around the giant planet Jupiter, so it experiences varying gravitational forces that periodically squeeze the moon’s rocky interior. This generates so much heat that Io is the most geologically active object in the solar system…
(read more: New Scientist)
image: NASA / JPL / University of Arizona

Astrophile:  Tour the Lava Lakes of Io

by Jacob Aron

Take a trip to Io, one of Jupiter’s many moons, and you will find pools of boiling hot lava nestled among the erupting peaks of raging volcanoes. Welcome to the Lake District from hell.

Now researchers have pored over snapshots taken by a passing space probe to make freshly detailed descriptions of three of Io’s infamous hotspots: Pillan, Wayland Patera and Loki Patera.

They found that each one has its own unique eruption style. The work not only helps flesh out our understanding of the dynamics of this malevolent moon, but could also offer a glimpse of what the early, highly volcanic Earth was like.

Io traces an oval-shaped orbit around the giant planet Jupiter, so it experiences varying gravitational forces that periodically squeeze the moon’s rocky interior. This generates so much heat that Io is the most geologically active object in the solar system

(read more: New Scientist)

image: NASA / JPL / University of Arizona

Scientists Find Evidence for Tectonic Plates on Jupiter’s Moon Europa

Scientists have found evidence of plate tectonics on Jupiter’s moon Europa. This indicates the first sign of this type of surface-shifting geological activity on a world other than Earth.

Researchers have clear visual evidence of Europa’s icy crust expanding. However, they could not find areas where the old crust was destroyed to make room for the new. While examining Europa images taken by NASA’s Galileo orbiter in the early 2000s, planetary geologists Simon Kattenhorn, of the University of Idaho, Moscow, and Louise Prockter, of the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, discovered some unusual geological boundaries.

"We have been puzzled for years as to how all this new terrain could be formed, but we couldn’t figure out how it was accommodated," said Prockter. "We finally think we’ve found the answer."

Plate tectonics is the scientific theory that Earth’s outer layer is made up of plates or blocks that move, which accounts for why mountain and volcanoes form and earthquakes happen…

(read more: Jet Propulsion Laboratory)

Image: Noah Kroese, I.NK

libutron
libutron:

San Rafael - Condor Agate | ©Uwe Reier
Discovered in 1992 by the former Argentinean actor, Luis de los Santos, the Condor Agate comes from a difficult-to-reach 7,000-foot elevated plateau near San Rafael, in Mendoza Province, Argentina. The site can only be reached by horse back.
The agate’s bright reds and yellows are made even more vivid by their contrasting bands of cooler, more-subtle hues. This agate was named after the large Condor birds that were flying over Luis de los Santos during the trip that he discovered the agate.
Locality: San Rafael, Argentina.
Reference: [1]

libutron:

San Rafael - Condor Agate | ©Uwe Reier

Discovered in 1992 by the former Argentinean actor, Luis de los Santos, the Condor Agate comes from a difficult-to-reach 7,000-foot elevated plateau near San Rafael, in Mendoza Province, Argentina. The site can only be reached by horse back.

The agate’s bright reds and yellows are made even more vivid by their contrasting bands of cooler, more-subtle hues. This agate was named after the large Condor birds that were flying over Luis de los Santos during the trip that he discovered the agate.

Locality: San Rafael, Argentina.

Reference: [1]

Natural methane leakage from the seafloor is far more widespread on the U.S. Atlantic margin than previously thought. 
A new joint study identified methane plumes in the water column between Cape Hatteras, North Carolina and Georges Bank, Massachusetts. The methane plumes are emanating from at least 570 seafloor cold seeps, mostly on the upper continental slope. For more info see our news release: U.S. Geological Survey

Natural methane leakage from the seafloor is far more widespread on the U.S. Atlantic margin than previously thought.

A new joint study identified methane plumes in the water column between Cape Hatteras, North Carolina and Georges Bank, Massachusetts. The methane plumes are emanating from at least 570 seafloor cold seeps, mostly on the upper continental slope.

For more info see our news release: U.S. Geological Survey

Monterey Bay Aquarium Research Institute (MBARI)
By studying deep-sea lava formations, MBARI’s submarine volcanism lab hopes to gain insight into potentially destructive eruptions on land or in shallow water. This image was taken with ROV Doc Ricketts’ video camera on the 2011 lava flow at Axial Volcano on the Juan de Fuca Ridge. It is the collapsed roof over a drained channel on the flow. There are living bacterial mat and hydrothermal clays on the lava flow surface.  For more information about MBARI’s Submarine Volcanism Project:
MBARI - Vulcanism

By studying deep-sea lava formations, MBARI’s submarine volcanism lab hopes to gain insight into potentially destructive eruptions on land or in shallow water. This image was taken with ROV Doc Ricketts’ video camera on the 2011 lava flow at Axial Volcano on the Juan de Fuca Ridge. It is the collapsed roof over a drained channel on the flow. There are living bacterial mat and hydrothermal clays on the lava flow surface.

For more information about MBARI’s Submarine Volcanism Project:

MBARI - Vulcanism

Japan’s cherry blossom stone is a natural wonder
Meet the cherry blossom stone from Japan - one of the most striking natural rock formations in the world.
by Bec Crew
So-called because when you crack them open, their internal cross-sections look like tiny golden-pink flowers, cherry blossom stones (sakura ishi in Japanese) get their beautiful patterns from mica, which is a commonly found silicate mineral known for its shiny, light-reflecting surface. 
These flower patterns weren’t always made of mica. They started their existence as a complex matrix of six prism-shaped crystal deposits of a magnesium-iron-aluminium composite called cordierite, radiating out from a single dumbbell-shaped crystal made from a magnesium-aluminium-silicate composite called indialite in the centre. 
Hosted inside a fine-grained type of rock called a hornfels - formed underground around 100 million years ago by the intense heat of molten lava - cherry blossom stones underwent a second significant metamorphosis in their geological lifespan when they were exposed to a type of hot water called hydrothermal fluids…
(read more: ScienceAlert! - Australia/NZ)
images: John Rakovan et al.

Japan’s cherry blossom stone is a natural wonder

Meet the cherry blossom stone from Japan - one of the most striking natural rock formations in the world.

by Bec Crew

So-called because when you crack them open, their internal cross-sections look like tiny golden-pink flowers, cherry blossom stones (sakura ishi in Japanese) get their beautiful patterns from mica, which is a commonly found silicate mineral known for its shiny, light-reflecting surface. 

These flower patterns weren’t always made of mica. They started their existence as a complex matrix of six prism-shaped crystal deposits of a magnesium-iron-aluminium composite called cordierite, radiating out from a single dumbbell-shaped crystal made from a magnesium-aluminium-silicate composite called indialite in the centre. 

Hosted inside a fine-grained type of rock called a hornfels - formed underground around 100 million years ago by the intense heat of molten lava - cherry blossom stones underwent a second significant metamorphosis in their geological lifespan when they were exposed to a type of hot water called hydrothermal fluids

(read more: ScienceAlert! - Australia/NZ)

images: John Rakovan et al.