Tuff Schist

The adventures of an unstable geologist

232 notes

distant-traveller:

Io in true color

The strangest moon in the Solar System is bright yellow. This picture, an attempt to show how Io would appear in the “true colors” perceptible to the average human eye, was taken in 1999 July by the Galileo spacecraft that orbited Jupiter from 1995 to 2003. Io’s colors derive from sulfur and molten silicate rock. The unusual surface of Io is kept very young by its system of active volcanoes. The intense tidal gravity of Jupiter stretches Io and damps wobbles caused by Jupiter’s other Galilean moons. The resulting friction greatly heats Io’s interior, causing molten rock to explode through the surface. Io’s volcanoes are so active that they are effectively turning the whole moon inside out. Some of Io’s volcanic lava is so hot it glows in the dark.

Image credit: Galileo Project, JPL, NASA

distant-traveller:

Io in true color

The strangest moon in the Solar System is bright yellow. This picture, an attempt to show how Io would appear in the “true colors” perceptible to the average human eye, was taken in 1999 July by the Galileo spacecraft that orbited Jupiter from 1995 to 2003. Io’s colors derive from sulfur and molten silicate rock. The unusual surface of Io is kept very young by its system of active volcanoes. The intense tidal gravity of Jupiter stretches Io and damps wobbles caused by Jupiter’s other Galilean moons. The resulting friction greatly heats Io’s interior, causing molten rock to explode through the surface. Io’s volcanoes are so active that they are effectively turning the whole moon inside out. Some of Io’s volcanic lava is so hot it glows in the dark.

Image credit: Galileo Project, JPL, NASA

(Source: apod.nasa.gov, via circuitdesign)

18 notes

mineralogue:

Calcium Carbonate Concretions: Ooids, Oolite, and Pearls
Image: surface of an ooidic limestone from Gunlock, Utah. From wikimedia commons, in the public domain.
Ooids are spheroidal grains less than 2mm in diameter displaying growth banding around a central nucleus or “seed”. They usually form in warm, shallow marine water, where the agitation of waves allows accretion around the nucleus on all sides. Warm water helps enhance the precipitation of calcium carbonate, which is the primary component of most ooids, usually in the form of aragonite. Larger grains formed similarly are known as pisoids. Ooids may also be composed of phosphate, chert, dolomite, or iron minerals such as hematite or goethite.
Oolite is a sedimentary rock formed from ooids, spherical grains, cemented together. Oolitic limestone is composed of calcite or aragonite ooids with calcite acting as the cement.
Aragonite ooids may sometimes resemble pearls, which are also calcium carbonate (either aragonite or a mixture of aragonite and calcite) deposited concentrically around a central “seed”. Ooids are not iridescent, but then neither are most pearls: almost all shelled molluscs are capable of forming pearls, but only those produced by specific oysters and mussels are the perfectly round, iridescent, gem-quality concretions that is most commonly associated with the word “pearl”.

mineralogue:

Calcium Carbonate Concretions: Ooids, Oolite, and Pearls

Image: surface of an ooidic limestone from Gunlock, Utah. From wikimedia commons, in the public domain.

Ooids are spheroidal grains less than 2mm in diameter displaying growth banding around a central nucleus or “seed”. They usually form in warm, shallow marine water, where the agitation of waves allows accretion around the nucleus on all sides. Warm water helps enhance the precipitation of calcium carbonate, which is the primary component of most ooids, usually in the form of aragonite. Larger grains formed similarly are known as pisoids. Ooids may also be composed of phosphate, chert, dolomite, or iron minerals such as hematite or goethite.

Oolite is a sedimentary rock formed from ooids, spherical grains, cemented together. Oolitic limestone is composed of calcite or aragonite ooids with calcite acting as the cement.

Aragonite ooids may sometimes resemble pearls, which are also calcium carbonate (either aragonite or a mixture of aragonite and calcite) deposited concentrically around a central “seed”. Ooids are not iridescent, but then neither are most pearls: almost all shelled molluscs are capable of forming pearls, but only those produced by specific oysters and mussels are the perfectly round, iridescent, gem-quality concretions that is most commonly associated with the word “pearl”.

12 notes

clifd:

Great roadside geology. I have always loved this particular highway cut in Southeast Missouri that exposes dolomites, limestones and rich red clays of the Cambrian-Ordovician Periods. Plus, the tall evergreens add a very striking visual appeal. ~Clif

clifd:

Great roadside geology. I have always loved this particular highway cut in Southeast Missouri that exposes dolomites, limestones and rich red clays of the Cambrian-Ordovician Periods. Plus, the tall evergreens add a very striking visual appeal. ~Clif

256 notes

romsromsroms:

The most perfect place I’ve been on this planet so far.

Only 20 people are allowed to visit Paria Canyon per day on a lottery system.

Most don’t make it to The Wave.

13 notes

s-c-i-guy:

Fossils Put Dent in Geoengineering Claims

During Earth’s last ice age, iron dust dumped into the ocean fertilized the garden of the sea, feeding a plankton bloom that soaked up carbon dioxidefrom the air, a new study confirms.


But the results deal a blow to some geoengineering schemes that claim that people may be able use iron fertilization to slow global warming. The planet’s natural experiment shows it would take at least a thousand years to lower carbon dioxide levels by 40 parts per million — the amount of the drop during the ice age.

Meanwhile, carbon dioxide is now increasing by 2 parts per million yearly, so in about 20 years human emissions could add another 40 parts per million of carbon dioxide to the atmosphere. Levels currently hover around 400 parts per million.

"Even if we could reproduce what works in the natural world, it’s not going to solve the carbon dioxide problem,” said Alfredo Martínez-García, a climate scientist at ETH Zurich in Switzerland and author of the study, published today (March 20) in the journal Science.

Read More

515 notes

ecowatchorg:

Evidence Finds BP Gulf Oil Disaster Causing Widespread Deformities in Fish

Crude oil from the 2010 Deepwater Horizon disaster causes severe defects in the developing hearts of bluefin and yellowfin tunas, according to a new study by a team of National Oceanic and Atmospheric Administration (NOAA) and academic scientists.

The findings, published in the Proceedings of the National Academy of Sciences on the 25th anniversary of the Exxon Valdez oil spill, show how the largest marine oil spill in U.S. history may have affected tunas and other species that spawned in oiled offshore habitats in the northern Gulf of Mexico…

Read more: Ecowatch

(via circuitdesign)

494 notes

thebrainscoop:

Devonian trilobite, Ceratarges spinosus, from around 417-354mya. The purpose of the spines on these trilobites is still uncertain, but perhaps we could compare their morphologies to those of modern-day beetles and arthropods to find similarities of use.

Sometimes looking at trilobites in a museum, all I can think is that battle-bot designers should be using these for inspiration.

thebrainscoop:

Devonian trilobite, Ceratarges spinosus, from around 417-354mya. The purpose of the spines on these trilobites is still uncertain, but perhaps we could compare their morphologies to those of modern-day beetles and arthropods to find similarities of use.

Sometimes looking at trilobites in a museum, all I can think is that battle-bot designers should be using these for inspiration.