Geochemist Steven Shirey is researching how Earth's continents formed. Continent formation spans most of Earth's history, continents were key to the emergence of life, and they contain a majority of Earth’s resources. Continental rocks also retain the geologic record of Earth's ancient geodynamic processes.

Shirey’s past, current, and future studies reflect the diversity of continental rocks, encompassing a range of studies that include rocks formed anywhere from the deep mantle to the surface crust. His work spans a wide range of geologic settings such as volcanic rocks in continental rifts (giant crustal breaks where continents split apart), ancient and present subduction zones (where the tectonic plates slide under one another), the mantle keels to the continents (root-like structures that penetrate to great depths), and rocks from the present oceanic mantle (an analog to pre-continental era of the Hadean to Paleoarchean, 4500 to 3200 million years ago).

Studying continents from the deepest samples led to Shirey’s recent research on diamonds carried to the surface in volcanic eruptions of kimberlite. Diamonds carry mineral “inclusions” which are the deepest, oldest, and most pristine mantle samples known. Diamonds with these inclusions are like tiny time-capsules from about 90-430 miles (150-700 km) deep within the Earth. The included minerals are often in their original condition and their analysis can reveal information on deep mantle mineralogy, the migration of carbon-bearing fluids, and ultimately sub-continental mantle keel formation and mantle geodynamics.

To conduct his work, Shirey uses Carnegie’s extensive chemistry and mass spectrometry labs to analyze the isotopes (different atoms of the same element with differing numbers of neutrons) of naturally occurring radioactive elements. These radioactive decaying elements, critical to his work and the work of all the geochemists at Carnegie, are like atomic clocks and decay at predictable rates. 

Shirey received his B.A. from Dartmouth College, his M.S. from the University of Massachusetts Amherst and his Ph.D. in geochemistry from SUNY Stony Brook. Before joining the Carnegie staff in 1985 he was a postdoctoral researcher at Carnegie. For more see http://home.dtm.ciw.edu/users/shirey

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Artist’s concept by Robin Dienel, courtesy Carnegie Science
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Pasadena, CA—Some of the extremely low-density, “cotton candy like” exoplanets called super-puffs may actually have rings, according to new research published in The Astronomical Journal by Carnegie’s Anthony Piro and Caltech’s Shreyas Vissapragada.

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Washington, DC— Carnegie astronomers Stephen Shectman and Alycia Weinberger were selected for the inaugural class of Fellows of the American Astronomical Society in recognition of their “extraordinary achievement and service” to the field. 

The newly established accolade will honor members of the organization for original research, innovative technique and instrumentation development, significant public outreach and educational efforts, and other noteworthy contributions to the society. To launch the program, the AAS selected 200 “legacy” fellows, including Shectman and Weinberger. Carnegie trustee Sandra Faber of UC Santa Cruz and former-

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Established in June of 2016 with a generous gift of $50,000 from Marilyn Fogel and Christopher Swarth, the Marilyn Fogel Endowed Fund for Internships will provide support for “very young budding scientists” who wish to “spend a summer getting their feet wet in research for the very first time.”  The income from this endowed fund will enable high school students and undergraduates to conduct mentored internships at Carnegie’s Geophysical Laboratory and Department of Terrestrial Magnetism in Washington, DC starting in the summer of 2017.

Marilyn Fogel’s thirty-three year career at Carnegie’s Geophysical Laboratory (1977-2013), followed

CALL FOR PROPOSALS

Following Andrew Carnegie’s founding encouragement of liberal discovery-driven research, the Carnegie Institution for Science offers its scientists a new resource for pursuing bold ideas.

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The Ludington lab investigates complex ecological dynamics from microbial community interactions using the fruit fly  Drosophila melanogaster. The fruit fly gut carries numerous microbial species, which can be cultured in the lab. The goal is to understand the gut ecology and how it relates to host health, among other questions, by taking advantage of the fast time-scale and ease of studying the fruit fly in controlled experiments.