Taxonomy term

july 2018

Piecing together the puzzle of Pannotia

Earth’s landmasses have joined together into supercontinents and then split apart again as many as six times in the planet’s history. 

31 Jul 2018

Lunar isotopes suggest early water on Earth

The moon is a child of catastrophe, born from a massive collision between the young proto-Earth and a Mars-sized object during the formation of the solar system. 

30 Jul 2018

Benchmarks: July 29, 1958: The Birth of NASA

Growing up in the suburbs of Washington, D.C., meant that my house was often frequented by guests who wanted to visit our nation’s capital. Without fail, this meant my family and I would be taking a trip to one of the Smithsonian’s most popular attractions, the National Air and Space Museum. I can’t count the number of times I visited the museum before I left for college, but it was a lot. Although glimpsing the museum’s collection of aircraft and spacecraft was cool at first, I would much rather have spent those afternoons wandering the halls of the National Museum of Natural History.

29 Jul 2018

Down to Earth With: Paleobiologist Rowan Lockwood

In 1608, Captain John Smith noted that oysters “lay as thick as stones” on the floor of the Chesapeake Bay. The shell reefs — built up by hundreds of years of oyster generations — were so large, ships wrecked against them. And each oyster was so massive, to eat one, you had to cut it into pieces — like a steak.

27 Jul 2018

Island-dwelling mammal had small brain, keen senses

A host of fossils has been discovered near the Romanian town of Haţeg, including 15 species of Late Cretaceous dinosaurs — some of them dwarf dinosaurs — and enormous pterosaurs with 12-meter wingspans, prompting the establishment of the Haţeg Country Dinosaurs Geopark in 2005.

26 Jul 2018

Diamonds and the Eocene climate of the Bell River Basin

Diamonds mined from the kimberlite pipes of the Lac de Gras diamond field in Northwest Territories, Canada, are among the world’s youngest known diamonds, dating from 75 million to 45 million years ago. In some cases, when the magmas that carried these diamonds to Earth’s surface encountered water-saturated rock at shallow depths, violent steam explosions called phreatomagmatic eruptions resulted. Such explosions can form volcanic craters known as maars, which often fill with water and accumulate lake sediment, along with soil and vegetation that collapse into them from their margins. In the case of the Panda kimberlite pipe at the Ekati Mine in the Lac de Gras area, maar sediments accumulated far below the surrounding terrain, such that they were later buried under glacial deposits rather than being eroded away by ice sheets during the past million years. Wood and other organic materials were entombed and preserved in their natural state, thereby preserving shreds of the Paleo-Bell River Basin.

25 Jul 2018

The Paleo-Bell River: North America's vanished Amazon

With similar geologic and tectonic histories, including a continuous mountain cordillera along their western margins, why does South America have a massive river draining a continentwide basin but North America does not? Before the Pleistocene, it did.
25 Jul 2018

Plumbing Masaya's lava lake

In recent years, volcanic activity at Nicaragua’s Masaya Volcano has been relatively benign, with small eruptive episodes occasionally producing a lava lake in a summit crater that has become one of the country’s top tourist attractions.

24 Jul 2018

Geologic Column: The raw and the cooked

A humorous take on some paleoanthropological aspects of fire.

23 Jul 2018

Cracking the temperature of columnar jointing

When molten rock cools and contracts, it sometimes cracks to form geometrically shaped columns. This process, called columnar jointing, has led to several famous geological structures.

20 Jul 2018

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