Earth and Planetary Sciences Event Calendar

Unless noted, all listed events are open to the general public.

Wednesday Seminar in Geology: GEL 190/290
Seminars are scheduled for Wednesday afternoon at 4:00 PM. Additional optional seminars that may be included as part of the Geology 190 series may be scheduled at other times.

Friday Lunch Seminar: "A Geology tradition since the Phanerozoic!"
Fridays at noon. Students and faculty give informal lectures on research, travel, or other interests.

Campus map: Earth & Physical Sciences Building | Roessler Hall

submit an event to the department calendar (restricted access)

Friday, May 29th, 2020, Friday Lunch Seminar

12:10 PM, Zoom Meeting (invite will be sent to gel-seminar)
Compositions of late accreted planetesimals  -- by Phil Carter, UC Davis

The presence of highly siderophile elements in Earth’s mantle indicates that a small percentage of the Earth’s mass was delivered after the closure of Earth’s core. The origin of 'late accreted' bodies is unknown, but the lack of a substantial outer solar system isotopic signature suggests that most late-accreted mass originated in the inner regions of the planet-forming disk near where the Earth formed. We will examine the compositions of planetesimals 'left over' from the main period of accretion in the terrestrial planet region. Many of these left over bodies are planetesimal-sized fragments ejected from planet embryos in collisions millions of years earlier.  If these fragments are later accreted by the planets, they would represent late accreted mass with isotopic compositions that naturally match the composition of the planet.