PALEO

paleo

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

Saglek Basin sediments suggest a Grand Canyon connection

Pollen makes an ideal fossil. Pollen grains — each only a few tens of microns in diameter — are produced in astronomical quantities by plants and record information about the ecosystem from which they came, thus providing a way to reconstruct past environments. Additionally, pollen is composed of a highly stable organic substance, sporopollenin, which resists decay as well as the high heat and pressure associated with deep burial, lithification and tectonism. It is so resistant, in fact, that it can be eroded from rock and recycled into younger sediments, a process recognized in the 1980s by V. Eileen Williams of the University of British Columbia in her studies of Paleo-Bell River sediments deposited in the Labrador Sea.

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

Mineral clue to finding perfectly preserved fossils?

The exquisitely preserved fossils found in the 500-million-year-old Burgess Shale in Canada are famous for the detailed anatomy they display. They also provide a rare and crucial record of the Cambrian Explosion, when most of the major animal groups first appeared.

17 Jul 2018

Pterosaurs flew into the Late Cretaceous

Late Cretaceous skies might have been more crowded than previously thought. Until recently, scientists thought the dearth of pterosaur fossils found from the Late Cretaceous meant that the flying reptiles were in decline before the catastrophic end of the Mesozoic. But the recent discovery in Morocco of several new pterosaur species suggests this unique branch of reptiles may have been thriving just before the end-Cretaceous extinction.

04 Jul 2018

Down to Earth With: Highway paleontologist Shane Tucker

When roads are built in fossil-rich states, paleontologists sometimes follow the trucks and bulldozers to make sure that the buried treasures that construction crews occasionally uncover — namely, remnants of ancient animals and plants — get out of the ground safely and into a museum to be cataloged and studied.

27 Jun 2018

Travels in Geology: Mesozoic masterpiece: England's Jurassic Coast

England's southwestern shore is renowned for the nearly continuous 185-million-year record of Earth's history exposed in its sensational seacliffs, which record one of the world's best stratigraphic sequences from the Mesozoic Era.

18 Jun 2018

Down to Earth With: Geologist and paleontologist David Wilcots

When David Wilcots was 4 years old, his parents took him to the American Museum of Natural History in New York City where he encountered his first giant dinosaur skeleton: a roughly 27-meter-long sauropod named Apatosaurus (though at the time it was still popularly known as Brontosaurus). “That just blew my mind,” he remembers. His passion for paleontology grew, branching from dinosaurs into early mammals, and led him to major in geology at Temple University in Philadelphia. In 1988, he earned a master’s in geology at Fort Hays State University in Kansas. But then, things didn’t go as planned. “When I got out of grad school, I looked for jobs in paleo, but couldn’t find any,” he recalls. “Environmental geology was the next best thing.” He began consulting with business and government agencies, and as time went on, his second choice of career grew on him.

29 May 2018

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