Chuck Meertens

Real‐time data received from Mount Erebus Volcano, Antarctica

Internal and eruptive volcano processes involve complex interactions of multi-phase fluids with the solid Earth and the atmosphere, and produce diverse geochemical, visible, thermal, elastic, and anelastic effects. Multidisciplinary experimental agendas are increasingly being employed to meet the challenge of understanding active volcanoes and their hazards [e.g.,Ripepe et al., 2002; Wallace et al., 2003]. Mount Erebus is a large (3794 m) stratovolcano that forms the centerpiece of Ross Island, Antarctica, the site of the principal US. (McMurdo) and New Zealand (Scott) Antarctic bases. With an elevation of 3794 m and a volume of ∼1670 km3, Erebus offers exceptional opportunities for extended study of volcano processes because of its persistent, low-level, strombolian activity (Volcano Explosivity Index 0–1) and exposed summit magma reservoir (manifested as a long-lived phonolitic lava lake). Key scientific questions include linking conduit processes to near-field deformations [e.g., Aster et al., 2003] ,explosion physics [ e.g., Johnson et al., 2003], magmatic differentiation and residence [e.g., Kyle et al., 1992], and effects on Antarctic atmospheric and ice geochemistry [e.g., Zreda-Gostynska et al., 1997]. The close proximity of Erebus (35 km) to McMurdo, and its characteristic dry, windy, cold, and high-elevation Antarctic environment, make the volcano a convenient test bed for the general development of volcano surveillance and other instrumentation under extreme conditions.

GPS monitoring of crustal deformation at Taal Volcano, Philippines

Data from a dual-frequency GPS network operated continuously from May 1998‐October 1999 on Taal volcano, Philippines, were processed on a daily basis to monitor processes of crustal deformation associated with volcanic activity. During the 16-month period of observations, displacements totaled nearly 30 mm in the horizontal and 50 mm in the vertical over 2.7 and 5.8 km baselines. Relative site velocities, estimated from daily site coordinates using 60-day tapered windows, vary significantly and can exceed 150 mm yr 21 in the horizontal. Velocity estimates were used to invert for parameters of a point-source model of elastic strain. During periods in which velocities are significant, the motions have a localized source at very high confidence, and the source magnitude term fluctuates between inflationary and deflationary behavior on time scales of weeks to months. The largest site velocities (and corresponding deformation model parameters) are time-correlative with anomalous bursts of hydrothermal activity and high-frequency local seismicity. In each instance the onset of deformation precedes both seismicity and hydrothermal activity, and the hydrothermal event coincides with a rapid shift in the velocity behavior. The relative timing of these phenomena suggests that deformation and seismicity both are responding to punctuated migration of hydrothermal fluids. q 2001 Published by Elsevier Science B.V.

Project helps constrain continental dynamics and seismic hazards

The Global Strain Rate Map project II-8, initiated in 1998 by the International Lithosphere Program (ILP), provides constraints for understanding continental dynamics and for quantifying seismic hazards in general. To date, the Global Strain Rate Map (GSRM) model is a numerical velocity gradient tensor fi eld solution (i.e., spatial variations of horizontal strain rate tensor components and rotation rates) for the entire Earth surface

Earthscope Program Workshop agrees on multi‐pronged education effort

EarthScope is a new Earth sciences initiative designed to dramatically improve our understanding of the evolution and dynamics of the North American continent. It is a partnership extending throughout the Earth science community, including more than 100 U.S. universities, the National Science Foundation, the National Aeronautics and Space Administration, the U.S. Geological Survey regional seismic network, and state geological surveys. Over 50 scientists and educators recently gathered to lay the foundation for EarthScopes education and outreach (E&O) program. The workshop brought together representatives of the Earth, space, and ocean science communities from colleges and universities, professional science and education societies, K-l2 schools, and state and federal agencies.