Feature Stories

Taking a quick scan

Anders Carlson and team in Greenland fjord

Anders Carlson and his team in a fjord in southern Greenland.

New instrument promises better, faster information about ancient earth

Scientists at Oregon State have long been studying materials archived in sediment cores to reconstruct past climate scenarios. Ancient ash, geochemical changes, and pollen give glimpses into a long-gone world, while also providing clues to our future. Yet, analyzing these cores can take weeks, if not months–until now.

A new instrument called an x-ray fluorescence scanner promises to cut that analysis time down to hours. Funded by the National Science Foundation through a collaborative, multi-college effort, the instrument will be one of only two west of the Midwest time zone, putting Oregon State on the frontier of paleoclimate research. The scanner can rapidly process up to 1.5-meter lengths of sediment core and measure the entire suite of elements from aluminum to uranium.

"It would take weeks or months to do this in a normal lab setting," said Anders Carlson, an associate professor in the College of Earth, Ocean, and Atmospheric Sciences and principal investigator. "This instrument does it much faster, and at a higher resolution."

The scanner can detect changes down to 0.1 millimeter in length–75 times narrower than an average human hair. A complete scan produces a colorful, high-resolution read-out of the core's composition–a kind of elemental alphabet whose letters tell a storied tale of Earth's history. Scientists can sync changes in elemental compositions to major events or hazards. Ice sheets, for example, slough off and deposit sediments that contain a unique elemental signature. This signature can help scientists pinpoint the collapse of ancient ice sheets–and determine the conditions that may spell a future collapse.

The instrument's versatility and power mean Carlson and colleagues could look at both short- and long-term changes, whether on a pre-industrial or paleo timescale. More broadly, the instrument could provide information on land-use changes, seismic records, or even past human activities. The cross-disciplinary effort involving colleges as diverse as Liberal Arts and Engineering demonstrates the scanner's far-reaching capabilities, says Carlson.

"The support of other colleges shows a wide interest across campus in looking at environmental and climactic change and how these changes impact the earth, both in terms of past interactions and modern-day humanity," he said.