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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Illustration of Neptune's interior purchased from Shutterstock
October 14, 2021

Washington, DC—A layer of “hot,” electrically conductive ice could be responsible for generating the magnetic fields of ice giant planets like Uranus and Neptune. New work from Carnegie and the University of Chicago’s Center for Advanced Radiation Sources reveals the conditions under which two such superionic ices form. Their findings are published in Nature Physics. 

As all school children learn, water molecules are made up of two hydrogen atoms and one oxygen atom—H20. As the conditions in which water exists change, the organization and properties of these molecules are affected. We can see this in our everyday lives when liquid water is boiled

Peter van Keken
September 30, 2021

Washington, DC— Carnegie geophysicist and geodynamicist Peter van Keken, whose work reveals Earth’s thermal and chemical evolution, was elected a Fellow of the American Geophysical Union.

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Carnegie Earth and Planets Laboratory isotope geochemist Anat Shahar
September 10, 2021

Washington, DC—Carnegie geochemist Anat Shahar, who probes the formation, evolution, and interior dynamics of Earth and other rocky planets, has been selected to give the Reginald Daly Lecture at the American Geophysical Union’s annual Fall Meeting in December.  

In honor of its namesake’s contributions to understanding the forces that shaped our planet, recipients for this recognition are selected for exemplifying excellence in the geosciences.

Earth and Planets Laboratory Staff Scientist Anat Shahar, also the institution’s Associate Science Deputy, uses a combination of isotope geochemistry and high-pressure, high-temperature experiments to

Diana Roman collecting samples, courtesy of Anna Barth, LDEO.
September 1, 2021

Washington, DC—Our planet provides ample research opportunities for scientists like Diana Roman, who has devoted her career to understanding the geologic forces that shape volcanic eruptions. She just needs to be on standby to seize them when they arrive.

Roman, recently named a Harry Oscar Wood Chair of Seismology at the Carnegie Institution for Science, wasn’t initially planning to travel to Iceland to get a look at the Fagradalsfjall “baby” volcano—in Geldingadalir—which erupted onto the scene in the Reykjanes Peninsula just this past March, mesmerizing the world with images of its cascading lava and “science fair”-style cone.

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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.

Carnegie Science Venture grants are internal awards of up to $100,000 that are intended to foster entirely new directions of research by teams of scientists that ignore departmental boundaries. Up to six adventurous investigations may be funded each year. The period of the award is two

Andrew Steele joins the Rosetta team as a co-investigator working on the COSAC instrument aboard the Philae lander (Fred Goesmann Max Planck Institute - PI). On 12 November 2014 the Philae system will be deployed to land on the comet and begin operations. Before this, several analyses of the comet environment are scheduled from an approximate orbit of 10 km from the comet. The COSAC instrument is a Gas Chromatograph Mass Spectrometer that will measure the abundance of volatile gases and organic carbon compounds in the coma and solid samples of the comet.

The Anglo-Australian Planet Search (AAPS) is a long-term program being carried out on the 3.9-meter Anglo-Australian Telescope (AAT) to search for giant planets around more than 240 nearby Sun-like stars. The team, including Carnegie scientists,  uses the "Doppler wobble" technique to search for these otherwise invisible extra-solar planets, and achieve the highest long-term precision demonstrated by any Southern Hemisphere planet search.

Ana Bonaca is Staff Member at Carnegie Observatories. Her specialty is stellar dynamics and her research aims to uncover the structure and evolution of our galaxy, the Milky Way, especially the dark matter halo that surrounds it. In her research, she uses space- and ground-based telescopes to measure the motions of stars, and constructs numerical experiments to discover how dark matter affected them.

She arrived in September 2021 from Harvard University where she held a prestigious Institute for Theory and Computation Fellowship. 

Bonaca studies how the uneven pull of our galaxy’s gravity affects objects called globular clusters—spheres made up of a million

Peter Gao's research interests include planetary atmospheres; exoplanet characterization; planet formation and evolution; atmosphere-surface-interior interactions; astrobiology; habitability; biosignatures; numerical modeling.

His arrival in September 2021 continued Carnegie's longstanding tradition excellence in exoplanet discovery and research, which is crucial as the field prepares for an onslaught of new data about exoplanetary atmospheres when the next generation of telescopes come online.

Gao has been a part of several exploratory teams that investigated sulfuric acid clouds on Venus, methane on Mars, and the atmospheric hazes of Pluto. He also

Anne Pommier's research is dedicated to understanding how terrestrial planets work, especially the role of silicate and metallic melts in planetary interiors, from the scale of volcanic magma reservoirs to core-scale and planetary-scale processes.

She joined Carnegie in July 2021 from U.C. San Diego’s Scripps Institution of Oceanography, where she investigated the evolution and structure of planetary interiors, including our own Earth and its Moon, as well as Mars, Mercury, and the moon Ganymede.

Pommier’s experimental petrology and mineral physics work are an excellent addition to Carnegie’s longstanding leadership in lab-based mimicry of the

Johanna Teske became the first new staff member to join Carnegie’s newly named Earth and Planets Laboratory (EPL) in Washington, D.C., on September 1, 2020. She has been a NASA Hubble Fellow at the Carnegie Observatories in Pasadena, CA, since 2018. From 2014 to 2017 she was the Carnegie Origins Postdoctoral Fellow—a joint position between Carnegie’s Department of Terrestrial Magnetism (now part of EPL) and the Carnegie Observatories.

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