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Narragansett, R.I. — March 8, 2004 — There is general agreement that the earth was formed “wet” and the earth’s interior has a high enough solubility of water to contain several oceans of water. It is also known that water has strong influences on the physical properties of the mantle and magma production. Yet mapping water in the earth’s interior and understanding its role in regulating the level of water on the surface of the planet in the history of the earth remain a grand challenge.

The äçÐÄvlogÃâ·ÑBÕ¾ Graduate School of Oceanography (GSO) will host the sixth in a series of Inaugural Lectures scheduled for the 2003-2004 academic year. “Water in the mantle: constraints from seismological observations” will be presented on Thursday, March 18, at 12:30 p.m. by Dr. Yang Shen, äçÐÄvlogÃâ·ÑBÕ¾ geological oceanographer. The lecture will be held in Corless Auditorium on the äçÐÄvlogÃâ·ÑBÕ¾ Bay Campus in Narragansett.

Shen’s talk will follow the thread of water in the mantle from the old and cold continental keels in southern Africa to the Icelandic hotspot. Seismological observations suggest that a relatively cold and water-rich mantle transition zone between about 400 – 700 km depth best explains the seismic velocities and transition zone thickness anomaly beneath the continental keels. Tomographic images of the mantle velocity beneath Iceland suggest that water may play an important role in the onset of partial melting in the upwelling mantle beneath the hotspot.

A resident of East Greenwich, Shen received a B.S. in structure geology and geophysics from Nanjing University, Nanjing, China, and an M.S. in geophysics from the Institute of Oceanology, Academy of Sciences, Qingdao, China. He also received an M.S. and a Ph.D. in geophysics from Brown University.

Shen’s current research interests include seismic structures of the oceanic crust and upper mantle. He is presently involved in constructing self-consistent seismological and geodynamic models of the Iceland hotspot. His current projects include studies of mantle discontinuities beneath Iceland, Hawaii, and southern Africa; earthquake activities at mid-ocean ridges; tomographic inversion of finite-frequency traveltimes; and simulations of broadband seismic wave propagation.

The audience for the Inaugural Lectures is the scientific community and the general public with an interest in and knowledge of science. Although technical in nature, Shen’s talk will not be aimed specifically at geological oceanographers. The purpose of the talks is to inform the scientific community about the nature and significance of research being carried out by GSO scientists.

The lectures are free and open to the public. Subsequent lectures will be held every third Thursday of the month at 12:30 p.m. in Corless Auditorium on the äçÐÄvlogÃâ·ÑBÕ¾ Bay Campus. For information, call 874-6246.