OMG science
fromPsychology Today
2 days agoRockhounding and Our Primordial Fascination With Crystals
Many people are innately attracted to crystals, leading to a lifelong passion for rockhounding and collecting.
Four protrusions appear to be arranged in pairs, each consisting of two connected branches surrounding a central depression. We really don't understand what any of these features represent anatomically.
Marine fossils have been discovered on mountain ranges around the world, including the Himalayas, Andes and Rocky Mountains, which scientists say were once covered by ancient seas before being pushed upward as continents collided and mountains formed.
Land is one of those things that can disappear even as you see it. It falls away beneath you, becoming merely the ground under your feet, because you're thinking about where you're going, or a place slowly blurring out of focus from the airplane window. Land is a primal word, primordial even, like lava. And it is a loaded word if, say, you're Indigenous or descend from a people whose land was taken from them.
A team of geologists has found for the first time evidence that two ancient, continent-sized, ultrahot structures hidden beneath the Earth have shaped the planet's magnetic field for the past 265 million years. These two masses, known as large low-shear-velocity provinces (LLSVPs), are part of the catalog of the planet's most enormous and enigmatic objects. Current estimates calculate that each one is comparable in size to the African continent, although they remain buried at a depth of 2,900 kilometers.
My father was a petroleum geologist. A lot of my childhood, he was gone, away on oil rigs in the Powder River Basin and remote parts of Wyoming, living in man camps long before cellphones. We had to wait days to talk to him. When he went into the nearest town to shower, he'd find a payphone and call us. I was always breathless with news.
Although Kansas has no active volcanoes, the region marks the southern reach of the Midcontinent Rift System, a massive tectonic event that nearly split North America apart in Earth's distant past. When magma forced its way through the crust during that period, it left behind hardened igneous rock and deep fractures that remain buried thousands of feet underground.
For example, reader David Erickson had this on his mind: If there were aliens 66 million light-years from Earth, how big a telescope would they need to see dinosaurs? Ha! I love this question. I've thought of it myself but never worked out the mathexcept to think, Probably pretty big, which turns out to dramatically underestimate the actual answer.
Now, in a recent study published in Geology, retired University of New Mexico geologist Karl Karlstrom and his colleagues conclude that the asteroid's impact shook Marble Canyon hard enough to dislodge great chunks of stone and send a landslide tumbling into the river. The debris formed a natural dam that backed up the Colorado for over 50 miles to near present-day Lees Ferry.