Science Opportunities - Basic Research Opportunities in Earth Science - page 51

Application of Molecular Biology to Earth Materials
Microorganisms and nanocrystalline phases are now recognized as playing a
key role in weathering and other fluid-soil-rock interactions within the Critical
Zone. Geomicrobiology is just now gaining momentum and has already
uncovered major surprises about how organisms influence mineralogical and
geochemical processes in the natural environment. Molecular biological
technologies offer powerful means for identifying both the species and the
functionality of organisms in a wide variety of environments (see “Geobiology”
above). Only a small fraction of the Earth's surface has been examined so far,
suggesting that many significant discoveries remain to be made, including
extreme habitats at depth in the crust.
Long-Term Observations in Natural Laboratories
Field observations are required to study material properties and processes on
length and time scales inaccessible in the laboratory, as well as to assess which
processes, among the many possibilities, are most significant in controlling
material properties under natural conditions. In situ measurements of geological
materials will be an important complement to laboratory experimentation for
monitoring and remediating the environment, characterizing geological
resources, and assessing geological hazards. Natural laboratories have enormous
potential as facilities where data sets with appropriate detail and precision can be
collected systematically over the long term under natural conditions. For
example, the San Andreas Fault Observatory at Depth (SAFOD), proposed as
part of the EarthScope initiative ( Box 2.2 ), will use deep drilling to recover
samples and collect in situ data on the fault zone properties that will permit a
better interpretation of laboratory experiments on rock friction and failure.
These opportunities in Earth and planetary materials research involve
technical advances, research efforts, or space missions that have already been
initiated. There are probably many other unforeseen developments that will take
place over the coming decade. It is new linkages between geoscientists and
researchers in other disciplines, such as chemistry, physics, and molecular
biology, that have led to many of the recent breakthroughs as well as several of
these opportunities.
The overall objective of research on Earth and planetary materials is to
obtain a full understanding of geological processes starting at the atomic scale.
Modern instrumentation, along with quantum and statistical mechanical
computations, are providing powerful new capabilities for achieving this
objective. Although many materials remain to be characterized, the accom