Pretty. And pretty deadly.
GeoPicture of the Week: Petrified Wood
Just like a number of creatures, wood can fossilize too.
GeoPicture of the Week: A colorful crystal mosaic
This is a beautiful specimen, from recent finds at the Wudong Mine of China.
#GeoPicture of the day: Amethyst
For all its beauty, amethyst is a fairly common variety of quartz. This here isn’t even a particularly special image, it’s how amethyst looks like most of the time. What is it about this mineral that makes it so special? Quartz itself is the second-most-abundant mineral in Earth’s crust. Amethyst is one of the more common of the quartz varieties. Amethyst usually
GeoPicture of the Week: Spaghetti Rock
What we’re seeing here is the ductility of the marble. According to the picture author, the marble dates from the Lower Proterozoic, more than 1.6 billion years ago to a period called the Aphebian Age. When rocks are subjected to high temperatures and pressures over long periods of time, they will either transform or break. Marble is not a particularly
#GeoPicture of the WeekThe Sahara Desert in Algeria, as seen by Japan’s ALOS satellite
It’s almost poetry: this image taken by the Advanced Land Observing Satellite “DAICHI” (ALOS) satellite shows the beauty and harshness of the Sahara desert. The Japanese Space Agency (JAXA) wrote: The heat and lack of water render vast desert areas highly unwelcoming, making satellites the best way to observe and monitor these environments on a large scale.
GeoPicture of the Week: Uvarovite
Uvarovite is a type of chromium-bearing garnet, one of the rarest minerals of garnets. Garnet species are found in many colors including red, orange, yellow, green, purple, brown, blue, black, pink, but uvarovite is always green.
#GeoPicture of the Week: Odyssey hits 60,000 Mars orbits
This image shows, in false color, the region around Gale Crater on Mars. It was taken by the 2001 Mars Odyssey spacecraft – but we just call it Odyssey. Odyssey has been orbiting the Red Planet for 14 years, 5 months and 20 days, recently celebrating a whopping 60,000 orbits around the planet, taking pictures and making valuable observations in the process. It currently
GeoPicture of the Week: The Moon’s Geology
It’s absolutely baffling that we’ve reached a level where we can not only study the geology of the Earth, but also that of other bodies in the solar system – in this case, the Moon. This is a false color mosaic constructed from a series of 53 images taken through three spectral filters by Galileo’s imaging system as the spacecraft flew
GeoPicture of the Week: Patagonia’s shrinking ice fields
The photo was taken with NASA’s Landat 8 satellite. Landsat is the longest-running enterprise for acquisition of satellite imagery of Earth, with the first one being launched in 1972. Since the end of the Little Ice Age, the ice fields of Patagonia and other parts of South America have been shrinking as global temperatures have increased. A number of studies
GeoPicture of the Week: Beautiful Hematite
Hematite is a fairly common mineral consisting of iron and oxygen (Fe2O3). Hematite can occur in a variety of colors, from black to steel or silver-gray, brown to reddish brown, or red. The name hematite is derived from the Greek word for blood, not for its red color itself, but for the trace it leaves behind when scratched or powdered. The spectral
GeoPicture of the Week: Snow-Covered Volcanoes Seen From Space
The picture was taken by an astronaut aboard the International Space Station (ISS), focusing on two snow-covered volcanoes in Russia’s Far East. The volcano in the center of the image is called Bolshaya Ipelka and it measures 40 kilometers (25 miles) at its base. The volcano has been inactive for a long time, but the valleys cut by glaciers along its side during the past million
GeoPicture of the Week: The Atlantic Ocean Floor
The geology of the ocean floor is truly spectacular – perhaps even more than land geology. Unfortunately, it’s really hard to study… you know, being on the ocean floor and all. But technician Marie Tharp and Professor Bruce Heezen from Columbia University’s Earth Institute put together several pieces of geology and geophysical information to not only create the most accurate
GeoPicture of the Week: Crinoid Fossils
Crinoids are marine animal (not plants) that have been around since the late Cambrian, some 500 million years ago. Crinoids usually have a stem used to attach themselves to a substrate, but many live attached only as juveniles and become free-swimming as adults. They are very fragile and require specific conditions to be preserved, so fossils like this one are very
GeoPicture of the Week: Xico Crater in Mexico
It’s a new year alright, and what better way to start it than with a GeoPicture? This is the Xico volcanic crater in Mexico. Located in the southern parts of of Mexico City in the municipality of Xico within the Chichinautzin volcanic field. The Chichinautzin volcanic is located in the Trans-Mexican Volcanic Belt, relatively close to the area where the Cocos tectonic plate
GeoPicture of the Week: Rhodochrosite Stalagmite ‘jawbreaker’
This mineral looks so delicious, I could gobble it up like candy!
GeoPicture of the Week: Natural Fluorite
Fluorite (also called fluorspar) is a mineral consisting of calcium fluoride, CaF2. It belongs to the halide minerals, alongside common salt (called halite in its mineral form). Halide minerals crystalize in the cubic (isometric) system, which means that its crystals are basically a cubic motif. Crystal twinning is common and adds complexity to the observed crystals. Its cleavage is perfect, as can be seen in this picture.
GeoPicture of the Week: Cubic Salt Crystals at Salar de Uyuni, Bolivia
These are perfectly cubical salt crystals, spotted at Salar de Uyuni, the world’s largest salt flat, located in Bolivia. Each crystal belongs to a specific crystal system – for salt it’s the cubic system. This means that the unit cell is in the shape of a cube. This is one of the most common and simplest shapes found in crystals and minerals,
GeoPicture of the Week: Polished Pallasite
This is a polished marble of a pallasite – a type of stony-iron meteorite, consisting mostly of centimeter-sized olivine crystals. Olivine is a silicate mineral often found in the Earth’s mantle. Pallasites were once thought to originate at the core-mantle boundary of differentiated asteroids that were subsequently shattered through impacts, but that theory has been replaced recently by another one, which
GeoPicture of the Week: Martian Chronicles
The Astro-geology team working on analyzing the photos from Curiosity Rover is having a busy week. They recently posted this amazing picture and announced their plans for the future. The plan for the weekend is to do a detailed analysis of the outcrop in front of us and then drive away and do some untargeted observations. Sol 1109 includes ChemCam