摘要:

It is generally assumed that the heavy‐ion plasma in the inner Saturnian magnetosphere is formed by the energetic plasma ions impacting and ejecting material from the icy satellites (Figure 1), a self‐sustained process known as ion sputtering [Lanzerotti et al., 1983;Eviatar, 1984;Richardson et al., 1986].Plasma‐ion sputtering of a surface is a well‐established laboratory technique for surface analysis and producing a vapor from a surface with a low vapor pressure; therefore, its potential relevance in Saturn's magnetosphere is intriguing. If the source of plasma in Saturn's inner magnetosphere is the surface of the icy satellites, then measurements of the composition of the freshly produced plasma can be used to determine the satellite surface composition [Johnson and Sittler, 1990]. This exciting prospect may be realized during the proposed encounter of Cassini with Saturn's satellite Dione in ∼2005 because of the high mass resolution of the plasma instruments carried on the s

ISSN:0002-8606    

DOI:10.1029/93EO00505

年代:1993

数据来源: WILEY

摘要:

A science plan to study continental margins has been in the works for the past 3 years, with almost 200 Earth scientists from a wide variety of disciplines gathering at meetings and workshops. Most geological hazards and resources are found at continental margins, yet our understanding of the processes that shape the margins is meager.In formulating this MARGINS research initiative, fundamental issues concerning our understanding of basic Earth‐forming processes have arisen. It is clear that a business‐as‐usual approach will not solve the class of problems defined by the MARGINS program; the solutions demand approaches different from those used in the past. In many cases, a different class of experiment will be required, one that is well beyond the capability of individual principle investigators to undertake on their own. In most cases, broadly based interdisciplinary studies will be n

ISSN:0002-8606    

DOI:10.1029/93EO00473

年代:1993

数据来源: WILEY