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For more information on these science news and feature story tips, please contact the public information officer at the end of each item at (703) 292-8070. Editor: Cheryl Dybas Contents of this News Tip:
DRYING ROCK CAN CAUSE REPEATED EARTHQUAKESPhysical changes within rocks below fault zones may lead to repeated earthquakes, according to NSF-funded geologists. Researchers Jay Ague, Jeffrey Park and Danny Rye of Yale University in New Haven, Connecticut, analyzed chemical reactions within Earth's middle crust, about 10-20 kilometers (6-12 miles) beneath the surface. Their study shows that rocks subjected to increases in pressure and temperature, such as those found in faults along boundaries where tectonic plates slide past each other, may release water over time. Loss of water and resulting increases in internal fluid pressures can cause these rocks to break, and possibly cause an earthquake -- if that break happens near an active fault line, like the San Andreas Fault. As water-bearing minerals move downward along a fault line, such changes in rock structure can lead to repeated quakes over decades and centuries, a time frame easily measurable in human time rather than in the millions of years commonly described as "geologic time." [Greg Lester] "XYZ ON A CHIP" INITIATIVE SEEKS NOVEL APPLICATIONS FOR MICROELECTRONICSAn innovative National Science Foundation (NSF) $10 million program is underway to encourage researchers to explore non electronic applications that take advantage of recent innovations in microelectronics -- called "XYZ on a Chip." "The invention of transistors and integrated circuits ushered in a second industrial revolution - the world of microelectronics," says Art Sanderson, director of the division of electrical and communications systems in NSF's engineering directorate. As components have shrunk in size, microelectronics systems have grown more complex -- solving many problems on scales also found in biology, chemistry and other fields. Examples include structural sensors that monitor and adjust stresses in "smart buildings," biosensors for controlled release of medicines in the body, and systems for automated control of freight trucks. "Microelectronics' most remarkable feat," Sanderson says, "is its elegant solution to the problem of complexity, and how its technology can be extended to other fields. `XYZ on a Chip' means, in essence, `You name it.'" NSF is seeking proposals that explore such themes as: non electrical processes and properties at the micro- and nano- scales; architecture, physical representations and design methodologies for non-electrical processes and microsystems; and techniques for rapid prototyping of novel chips among others. NSF will make between 20 and 25 awards in the range of $100,000 to $300,000 per year for up to three years. [Joel Blumenthal] For more information, see the program announcement at: http://www.nsf.gov/cgi-bin/getpub?nsf9931 FORESTS YIELD CLUES TO CARBON CYCLE ON WARMING PLANETA team of scientists funded by NSF and affiliated with Harvard University in Massachusetts has been studying the respiration of Harvard Forest -- 3,000 acres of mixed oak and maple hardwood with scattered white pine and some red-pine plantations in central Massachusetts. One of 21 NSF Long-Term Ecological Research (LTER) sites in North America and Antarctica, Harvard Forest is increasing its uptake of carbon, according to scientist Steven Wofsy of Harvard University. The annual net uptake varied from 1.4 to 2.8 metric tons of carbon per hectare between 1991 and 1995. "People were surprised that the forest was taking up that much carbon," says Wofsy. "The forest appears to be responding to longer growing seasons, the result of warmer temperatures over the last 30 years, by taking up more carbon dioxide." At Harvard Forest's Environmental Measurement Site, automated instruments mounted at several heights on a 100-foot tower take continuous measurements at half-hour intervals of a variety of chemicals entering and leaving the forest canopy. Among chemicals measured are carbon dioxide, ozone, nitrogen oxides, carbon monoxide and several hydrocarbons. [Cheryl Dybas] For more information on all 21 NSF LTER sites, see: www.lternet.edu
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