November 30, 1998
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:
Physical 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]
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An 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
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A 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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