Science Opportunities - Basic Research Opportunities in Earth Science - page 33

New Tools and Observations
Many science disciplines—hydrology, geomorphology, biology, ecology,
soil science, sedimentology, materials research, and geochemistry—are bringing
new and powerful research tools to bear on the study of the Critical Zone as an
integrated system of interacting components and processes. It is now possible to
study the Critical Zone over a much greater range of length and time because of
the wealth of data from satellites and aircraft that provide global information on
scales from seconds to decades; advances in geochronology that extend the
detailed record of near-surface environments to millions of years; imaging
methods (e.g., electron and atomic force microscopes) and spectroscopic tools
that probe soil materials to the atomic scale; and new information technologies,
which permit the manipulation of large data sets and a variety of numerical
simulations, from ab initio models of atomic and molecular interactions to global
ocean and atmospheric circulation and mountain belt evolution. These
technological advances have set up opportunities for novel cross-disciplinary
activities.
• Synchrotron-based X-ray spectroscopy can be applied in tandem with
computational geochemistry to elucidate the molecular-scale mechanisms
of key aqueous geochemical reactions related to mineral weathering,
contaminant sorption and desorption, and nutrient cycling.
• High-resolution electromagnetic and acoustic imaging of hydrological
systems can be combined with molecular-scale mechanisms of aqueous
geochemical reactions for accurate representations of transport in reactive
systems. Such representations are essential for addressing silicate mineral
weathering—a source of nutrients to the biosphere and a major control on
the long-term CO 2 budget—and contaminant transport.
• The techniques of isotope geochemistry and molecular biology reveal the
pathways involved in biogeochemical cycles and the formation of
secondary minerals in weathering environments. 3 New geochemical and
stratigraphic tools and techniques for dating individual minerals are
furnishing insights into the behavior of the Earth's surface with increasing
temporal resolution.
• Remote-sensing data, digital elevation models, and special dating
techniques such as cosmogenic nuclide exposure ages can be used to
validate a new generation of geomorphic transport models. 4 These
models will allow a
4 A Vision for Geomorphology and Quaternary Science Beyond 2000, Results of a
workshop held in Minneapolis, Minnesota, February 6-7, 2000.
3 Research Opportunities in Low-Temperature and Environmental Geochemistry, results
of a workshop held in Boston, Massachusetts, June 5, 1999.