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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NASEM astrobiology briefing artwork
October 10, 2018

Washington, DC—NASA should incorporate astrobiology into all stages of future exploratory missions, according to a new report from the National Academies of Sciences, Engineering, and Medicine presented Wednesday by the chair of the study, University of Toronto’s Barbara Sherwood Lollar, and by Carnegie’s Alan Boss, one of the report’s 17 expert authors.

Astrobiology addresses the factors that allowed life to originate and develop in the universe and investigates whether life exists on planets other than Earth. This highly interdisciplinary and constantly adapting field incorporates expertise in biology, chemistry, geology, planetary science, and physics. According to the report’s

October 4, 2018

Sarah Stewart was awarded a prestigious MacArthur fellowship for: “Advancing new theories of how celestial collisions give birth to planets and their natural satellites, such as the Earth and Moon.”

Stewart is currently a professor in the Department of Earth and Planetary Sciences at the University of California Davis. Her group studies the formation and evolution of planetary bodies by using shock wave experiments to measure the properties of materials and conducting simulations of planetary processes. She was a Carnegie postdoctoral fellow from 2002 to 2003. For more see Macfound.org
 

October 2, 2018

Washington, DC—Carnegie’s Scott Sheppard and his colleagues—Northern Arizona University’s Chad Trujillo, and the University of Hawaii’s David Tholen—are once again redefining our Solar System’s edge. They discovered a new extremely distant object far beyond Pluto with an orbit that supports the presence of an even-farther-out, Super-Earth or larger Planet X.

The newly found object, called 2015 TG387, was announced Tuesday by the International Astronomical Union’s Minor Planet Center.  A paper with the full details of the discovery has also been submitted to The Astronomical Journal.

2015 TG387 was discovered about 80 astronomical units (AU) from the Sun, a measurement

Erik Hauri in the lab at Carnegie's Department of Terrestrial Magnetism
September 6, 2018

Washington, DC—Carnegie geochemist Erik Hauri, whose work upended our understanding of the Moon’s formation and the importance of water in Earth’s interior, died Wednesday in North Potomac, MD, following a battle with cancer. He was 52.

Hauri joined Carnegie as a staff scientist in 1994 and spent nearly 25 years investigating the geochemistry of the Earth, Moon, and other celestial objects.  Hauri had a particular interest in water, which he called the most-important molecule in our Solar System, saying that understanding where it came from and how it got distributed among the planets and various other bodies would unlock the secrets of how our Solar System evolved.

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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 by four years at the University of California,

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 years,

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.

Carbon plays an unparalleled role in our lives: as the element of life, as the basis of most of society’s energy, as the backbone of most new materials, and as the central focus in efforts to understand Earth’s variable and uncertain climate. Yet in spite of carbon’s importance, scientists remain largely ignorant of the physical, chemical, and biological behavior of many of Earth’s carbon-bearing systems. The Deep Carbon Observatory (DCO) is a global research program to transform our understanding of carbon in Earth. At its heart, DCO is a community of scientists, from biologists to physicists, geoscientists to chemists, and many others whose work crosses these disciplinary lines,

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. 

Nick Konidaris is a staff scientist at the Carnegie Observatories and Instrument Lead for the SDSS-V Local Volume Mapper (LVM). He works on a broad range of new optical instrumentation projects in astronomy and remote sensing. Nick's projects range from experimental to large workhorse facilities. On the experimental side, he recently began working on a new development platform for the 40-inch Swope telescope at Carnegie's Las Campanas Observatory that will be used to explore and understand the explosive universe.

 Nick and his colleagues at the Department of Global Ecology are leveraging the work on Swope to develop a new airborne spectrograph that will be used to provide a direct

Experimental petrologist Michael Walter became director of the Geophysical Laboratory beginning April 1, 2018. His recent research has focused on the period early in Earth’s history, shortly after the planet accreted from the cloud of gas and dust surrounding our young Sun, when the mantle and the core first separated into distinct layers. Current topics of investigation also include the structure and properties of various compounds under the extreme pressures and temperatures found deep inside the planet, and information about the pressure, temperature, and chemical conditions of the mantle that can be gleaned from mineral impurities preserved inside diamonds.

Walter had been at

Guoyin Shen's research interests lie in the quest to establish and to examine models for explaining and controlling the behavior of materials under extreme conditions. His research activities include investigation of phase transformations and melting lines in molecular solids, oxides and metals; polyamorphism in liquids and amorphous materials; new states of matter and their emergent properties under extreme conditions; and the development of enabling high-pressure synchrotron techniques for advancing compression science. 

He obtained a Ph.D. in mineral physics from Uppsala University, Sweden in 1994 and a B.S. in geochemistry from Zhejiang University, China in 1982. For more