To answer questions about the planet’s future, earth scientists look to the past. But for too long, the arbiters of these stories—the geochronologists who date the age of rocks—have been underfunded and uncoordinated. That could change if the National Science Foundation (NSF) funds a new consortium for geochronology—a major recommendation of a report released today by the National Academies of Sciences, Engineering, and Medicine (NASEM).
At a cost of up to $10 million annually, the National Consortium for Geochronology, as the report calls it, would develop new dating techniques while providing dates as a service to NSF-funded researchers. It could also calibrate, standardize, and improve the efficiency of different methods, which are based on the radioactive decay of elements within a rock.
The consortium could help geochronology emerge from a deep slump, says Mark Harrison, a geochemist at the University of California (UC), Los Angeles, who led a 2015 proposal cited in the new report. Ever since the U.S. Geological Survey backed away from the field in the 1990s, “We’ve been bootlegging innovation to routine analysis,” he says. “At the level being proposed, a young person could have the ambition to do something transcendental.”
The NASEM report is one of the many “decadal surveys” commissioned and used by funding agencies to guide priorities. In addition to calling for infrastructure like the geochronology consortium, the report highlights 12 science questions to be tackled by NSF’s $180 million earth sciences division (EAR), from the origin of plate tectonics billions of years ago, to the way million-year-old paleoclimate records can help predict climate change. “Geochronology is intimately woven into every single question,” says Tanja Bosak, a geobiologist at the Massachusetts Institute of Technology and a co-author of the report, titled Earth in Time.
The geochronology funding could also help iron out discrepancies between labs and dating systems, says Dennis Kent, a paleogeographer at Rutgers University, New Brunswick, and study co-author. The field has embraced techniques and dates based on uranium’s decay to lead, but other systems, such as those based on argon decay, are still contentious, he says. “This might be a way to get the community up to similar standards.”
The report also recommends that NSF invest up to $3 million to build a new anvil press. Such an instrument, capable of focusing loads up to 10,000 tons onto rock samples smaller than a pea, can simulate the pressures in Earth’s core. Researchers want an anvil, similar to ones in Europe and Asia, that can work on larger, multimillimeter-size samples so they can perform a wider variety of measurements. Although a few labs aim for those capabilities, “they are harder and harder to sustain and fund,” says Nancy Ross, a mineralogist at Virginia Polytechnic Institute and State University. “Technical support is always an issue.”
Finally, the agency should create a Near-Surface Geophysics Center, the report recommends. Over the past 2 decades, the shrinking price, size, and autonomy of geophones, seismometers, and other instruments has led geophysicists, who typically study deep Earth, to explore the shallows, some 100 meters and up—Earth’s dynamic skin. “It’s surprisingly one of the least understood places on the Earth,” says Bill Dietrich, a geomorphologist at UC Berkeley, and report co-author. Many emerging tools, such as using nuclear magnetic resonance to study ground porosity, show potential but need further development. Such a center would move the field forward, costing only some $6 million over 4 years, the authors estimate.
The NASEM report is notable for its restraint: The survey was directed to assume a flat budget for the division. It did, however, recommend the continued development of several ambitious proposals that would require significant new investment from NSF, beyond the reach of the EAR budget. One is the SZ4D initiative, which would study one or several subduction zones, where oceanic crust dives beneath continents, and cost hundreds of millions of dollars. Another is the Continental Critical Zone, costing more than $100 million, which would map soil, rocks, and hydrology down through the water table across North America. It would build on the agency’s Critical Zone Observatory program, which ends this year. “These are major discovery opportunities, and separate funding should be sought for them,” Dietrich says.