Science Opportunities - Basic Research Opportunities in Earth Science - page 45

• the relative importance of intrinsic and extrinsic factors in controlling the
nature and rates of biological innovation;
• the rates and selectivities in biological extinction and recovery, and how
these scale to duration, magnitude, and geographic extent of changes in
the physical and biological environment; and
• the causes of environmental change, including the ways in which
biological processes contribute to and can be used to remediate
environmental damage.
EARTH AND PLANETARY MATERIALS
Research on Earth and planetary materials has undergone significant growth
over the past two decades, building on major advances in the well-established
domains of geochemistry, mineralogy, petrology, and soil science, as well as in
the newer fields of geomicrobiology and biomineralogy, mineral and rock
physics, and nanophase and planetary materials studies. This research is also
being stimulated by new collaborations of geoscientists with chemists, physicists,
molecular biologists, and materials scientists. Together, these disciplines have
laid the groundwork for the ambitious objective of attempting to understand, from
the atomic level up, the most significant processes that determine the current state
and geological evolution of planets in general and Earth in particular.
Recent Advances
Earth and planetary materials research is based on an atomistic approach—
establishing properties at the molecular level in order to understand materials and
processes at much larger scales. It has involved the development of major new
research tools. For example, mineral physicists have been at the forefront of
developing synchrotron beamlines for microdiffraction and spectroscopy,
experimental tools for studying materials at ultrahigh pressures and temperatures,
resonance techniques for superprecise measurements of elastic properties, and
quantum mechanical methods for modeling complex minerals. Characterizing
Earth materials with such methods is essential for quantifying the underlying
processes and driving forces at play.
These capabilities also make it possible, for the first time, to study naturally
occurring nanophases and mineral surfaces in great detail, for instance, tracking
low concentrations of elements in soils and related biological materials.
Understanding how both naturally occurring and human-introduced