Taxonomy term

isotope

Long-gone supernova sprinkles rare isotope

At the end of a star’s lifecycle it collapses and explodes into a supernova, spewing rare elements and isotopes outward into space. In the last 1,000 years, three supernova events have been observed in the Milky Way Galaxy. Now scientists have detected a rare iron isotope, iron-60, in our solar system that hints that a supernova may have exploded nearby within the last few million years.

09 Aug 2016

Underwater Roman marble traced to Greece, Italy and Turkey

From the first century B.C. to the third century A.D., the city of Baiae, located on the west coast of Italy, near Naples, was the preferred summer home of Roman emperors, including Augustus and Nero. The once-grand city now lies under more than 5 meters of water due to coastal subsidence, and is preserved as the Underwater Archaeological Park of Baiae. Researchers have now traced the opulent city’s white marble floors to some of the most famous quarries in Italy, Greece and Turkey.

03 Jun 2016

Growth rings in rocks reveal past climate

Paleoclimate studies often depend on mineral or sediment layers deposited seasonally or annually in caves, lakes and ice, but such records leave gaps where caves, lakes or ice sheets aren’t found. Now, scientists using a new technique that analyzes calcite layers ringing pebbles and rocks in arid landscapes are opening a new window onto the climate history of western North America. And because such deposits are found all over the world, the technique might prove to be a useful new tool for studying paleoclimate globally.

02 May 2016

North Sea uplift caused Jurassic cooling event

The climate of the Jurassic, long envisioned as ubiquitously warm from the equator to the poles, was actually more dynamic, sometimes cooling dramatically, according to a new study. The research joined isotopic and sedimentological data to suggest that an abrupt cooling event occurred in the midlatitudes early in the Middle Jurassic as a result of changing ocean currents associated with a feature known as the North Sea Dome.

31 Mar 2016

Ancient eggshells may reveal dinosaur body temperatures

Whether dinosaurs had metabolisms more like slow, cold-blooded reptilians or fast, warm-blooded birds has long been a mystery. Fossilized bones, which don’t preserve the delicate cell membranes that facilitate heat production in warm-blooded animals, are not likely to answer the question. Fossilized eggshells, however, might be just the ticket to determining the past body temperatures of egg-laying females, which, scientists say, might help address whether the dinosaurs’ metabolisms were warm or cold.
 
27 Jan 2016

Isotopes could reveal ancient American turquoise trade

For centuries before the arrival of Europeans, turquoise was prized among pre-Hispanic cultures of North America. Caches of the distinctive, creamy-blue-green mineral have been unearthed in crypts and other ritually significant structures in what are now the southwestern United States and northern Mexico. Farther south, in Mesoamerica, archaeologists have found elaborate mosaic masks and ornamentation made of turquoise pieces. Despite multiple anthropological and historical hints, identifying where the turquoise used by different civilizations came from has proven difficult. But in a recent study, scientists have described a geochemical fingerprinting technique that may help parse the geographic origins of turquoise specimens and illuminate trade routes in ancient America.
 
09 Nov 2015

One-two punch of past warming may hold lessons

Geologists are fond of the saying, “The past is key to the future.” Unfortunately, the past has been a poor guide when it comes to understanding modern climate change. Now, however, a new study suggests that one episode — a spike in global temperatures that occurred about 55 million years ago — may be a better analog than previously thought, and could yield insights into the planet’s future.

 
09 Apr 2015

New lunar research answers old questions, poses others

From its close perch in the sky, the moon has long mystified artists, lovers and scientists. Now a quartet of recent papers — all of which touch on the moon’s violent birth and turbulent infancy — may help scientists put two long-standing lunar mysteries to rest, while deepening a third enigma and suggesting a speculative solution to a fourth.

23 Oct 2014

New climate record challenges ideas about recent glaciations

Predicting how a changing climate and rising sea levels might impact humans in the future requires an understanding of how Earth has changed in the past. So scientists are continually seeking more and better data to help illuminate earlier conditions.
 

08 Sep 2014

Down to Earth With: Naomi Levin

Stable isotope geochemist Naomi Levin, a native New Yorker, says she could easily imagine alternate career paths that would have been more in line with her urban roots. But the hands-on nature of both fieldwork and lab work lured her to geology and anthropology. And after working with a string of prominent geochemists — including Jay Quade, Thure Cerling and John Eiler — as a graduate student and post-doctoral researcher, Levin has quickly moved to the top of her field.

09 Jan 2014

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