Institute Of Geophysics And Planetary Physics Research Articles

J. Freeman Gilbert (1931-2014)

James Freeman Gilbert, a renowned professor emeritus of geophysics in the Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics (IGPP) at Scripps Institution of Oceanography, University of California San Diego, died in Portland, Oregon, on 15 August 2014 from injuries related to an auto accident. He was 83 years old. J. Freeman Gilbert (1931–2014). A leading contributor in computational geophysics, seismology, earthquake sources, and geophysical inverse theory, Gilbert was the author of numerous research papers, book chapters, reviews, and other publications. “Since the moment he arrived at Scripps in 1961 after being recruited by Walter Munk, Freeman Gilbert was recognized as a true pioneer in Earth studies, armed with his knowledge and drive in applying modern computational tools to seismic problems,” said Margaret Leinen, director of Scripps. “Scripps is extremely grateful for all of Freeman’s contributions to science and to the education and training initiatives that he shaped at Scripps and the young UC San Diego campus.” Gilbert was a leading expert in seismic research. With his Scripps …

Insight from the unexpected

The NASA Stardust mission returned samples from comet 81P/Wild 2, an active Jupiter-family comet that is believed to have formed at a heliocentric distance beyond the orbit of Neptune. The study of the samples has provided a critical first look at the micrometer and larger solid materials that were at the edge of the solar system at the time that Kuiper Belt comets formed. Analysis of the samples has involved a number of challenges and surprises. These issues and the full implications of the information that the samples provide were intently discussed at the Timber Cove II meeting October 2628, 2008. The meeting was sponsored by the Institute of Geophysics and Planetary Physics (IGPP) and it was held at a ruggedly beautiful and remote location on the Sonoma coast of northern California once protected by a Russian fort. Seventeen of the papers presented at the meeting are presented in this volume.

Formation, dynamics, and impact of plasmaspheric plumes

Workshop on Plasmaspheric Drainage Plumes, Taos, New Mexico, 9–13 October 2006Plasmaspheric plumes result from erosion of the plasmasphere. The Institute of Geophysics and Planetary Physics (IGPP) Workshop on Plasmaspheric Drainage Plumes was convened in Taos, N. M., on 9–13 October 2006 to examine outstanding questions about the formation and dynamics of plumes, and the impact of plumes on the near‐Earth space environment (geospace). A second workshop on plasmaspheric drainage plumes is planned for late 2007.

The Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics (IGPP)

increasing specialization at Scripps has drawn away some of our colleagues in the fluid earth field. • One of the most challenging problems has been the mix between individual scholarship and the teamwork required to collect data on a global scale. The pendulum has swung back and forth. Curiously, it was the work and interest of the “scholars” that initiated the most notable team efforts. • We have made a concerted effort to provide an attractive home for the IGPP family. The directors and their wives participated to an unusual (perhaps unique) degree in the selection of architects and the subsequent planning, design, and construction of both IGPP laboratories in the 1960s and 1990s. What follows are first-person recollections of what happened (or what we think we remember happened) during our tenure as directors. This is by no means a history of the institute. There is little coherence, and no attempt at completeness. We ask the forgiveness of our many partners whose contributions are not an explicit part of this sketch.

Gilbert receives 1999 William Bowie Medal

J. Freeman Gilbert was awarded the William Bowie Medal at the AGU Spring Meeting Honors Ceremony, which was held on June 2, 1999, in Boston, Massachusetts. The medal recognizes outstanding contributions to fundamental geophysics and unselfish cooperation in research.Freeman Gilbert was a geophysical pioneer, even as a student at the Massachusetts Institute of Technology, where he used the Whirlwind computer to apply computational methods to seismic problems. Later at the Institute of Geophysics and Planetary Physics (IGPP),at the University of California, Los Angeles, where he began his professional university career, he wrote a series of papers on the computation of synthetic seismograms in simple media.

A spaceborne magnetometer tested under extended temperature conditions (experiment MAREMF-OS/MARS-96)

The Space Research Institute of the Austrian Academy of Sciences took part in the experiment MAREMF (MARtian Electrons and Magnetic Field) which consists of a dual fluxgate magnetometer (MAREMF-OS and MAREMF-IS) and a 3D electron spectrometer (MAREMF-ES). MAREMF was part of the plasma payload of the Russian MARS-96 mission which unfortunately failed half an hour after launch because of a rocket problem. Digital electronics and firmware of the MAREMF-OS magnetometer were developed at the Space Research Institute, Graz, Austria. The sensor was supplied by the Institute of Geophysics and Planetary Physics (IGPP), UCLA, USA. The sensor electronics were jointly developed with the IGPP. Due to the expected temperature conditions during cruise phase and the orbit around Mars, an improved low-field temperature test facility for magnetic field sensors was constructed at the Magnetometer Laboratory of the Space Research Institute. It enabled all basic test and calibration measurements for magnetic field sensors within a temperature range of C. Additionally, a three-layer magnetic shielding set generated a low-field environment. The same facility is now used for the development and calibration of a new generation of magnetic field sensors for the ROSETTA mission to comet P/Wirtanen.

1991 LANL Mantle Convection Workshop

Since 1985, Los Alamos National Laboratory's (LANL) Institute of Geophysics and Planetary Physics (IGPP) has hosted a mantle convection workshop. Each year, senior scientists and graduate students meet for 2 weeks of formal and informal presentations and hands‐on working groups. The workshop format has been to define focus topics and activities which are discussed in small subgroups. Focus group reports are then made to summarize previous work and define avenues of future research on specific topics. From July 8 to 19, 1991, the primary focus of discussion was mantle plumes. Mantle discontinuities and the effect of tectonic plates upon mantle convection were focus topics in previous workshops. Additional focus topics for this workshop included the differences between 2D and 3D convection and a discussion of benchmark problems for the European convection workshop, held in August 1991 in Weilburg, Germany. In addition to presentations, focus group reports, and the exchange of ideas by geodynamics researchers, a number of guest speakers from related fields helped provide background on relevant model constraints, motivate discussion, and promote communication between fields.

Ironworkers Convention I: Workshop on Physics of Iron

This special section reports on a Workshop on the Physics of Iron that was held June 14–16, 1989, at Los Alamos National Laboratory, Los Alamos, New Mexico. Sponsored by the Institute of Geophysics and Planetary Physics (IGPP) of the University of California, the workshop was hosted by the Los Alamos branch. The IGPP's Center for Earth and Planetary Interiors (CEPI), of which the three convenors are members, provided coordination during the publication stages. Topics of study included the physical properties of iron, its phase transitions and phase diagram to high temperatures and pressures, its alloying properties, and theoretical explanations of these features.