BEGIN:VCALENDAR
VERSION:2.0
PRODID:icalendar-ruby
CALSCALE:GREGORIAN
X-WR-CALNAME:COG3 Seminar - Alicia Cruz-Uribe (University of Maine Orono)
X-WR-TIMEZONE:Eastern Time (US & Canada)
BEGIN:VEVENT
DTSTAMP:20260617T195419Z
UID:tag:localist.com\,2008:EventInstance_42474894509493
DTSTART:20230414T140000Z
DTEND:20230414T150000Z
DESCRIPTION:Title: Ex uno plures: the revolution of in situ Rb-Sr geochrono
 logy\n\n \n\nAbstract: In situ single spot Rb-Sr isochron dating of micas 
 by LA-MC-ICP-MS/MS represents a new analytical and geologic horizon for th
 e Rb-Sr system. Single spot Rb-Sr isochrons in biotite from western Maine\
 , USA\, record three distinct events that are obscured by the traditional 
 spot dating approach. The punctuated nature of the events recorded by the 
 Rb-Sr system is somewhat at odds with the broad\, long-lived cooling histo
 ries that are typically recorded by the Ar/Ar system. With their perfect c
 leavage and propensity to hold ions in interlayer sites\, micas are not ty
 pically thought of as minerals that record multiple geologic events\, and 
 are considered to be sensitive to resetting by thermal and fluid-mediated 
 processes. Here we show that very distinct isotope ratio and trace element
  zones are preserved in biotite\, marking a departure from the conventiona
 l view of Rb and Sr retention in mica minerals. The prospects for single s
 pot isochron dating combined with isotope ratio mapping by LA-MC-ICP-MS/MS
  open up a new frontier for mica geochronology.\n\n \n\nAbout this Series:
  The Chemical Oceanography\, Geology\, Geochemistry\, and Geobiology Semin
 ar [COG3] is a student-run seminar series. Topics include chemical oceanog
 raphy\, geology\, geochemistry\, and geobiology. Contact cog3_seminar_orga
 nizers@mit.edu for more information and Zoom password.
GEO:42.360158;-71.089183
LOCATION:Building 54\, Room 915
SUMMARY:COG3 Seminar - Alicia Cruz-Uribe (University of Maine Orono)
URL;VALUE=URI:https://calendar.mit.edu/event/cog3_seminar_-_alicia_cruz_uri
 be_university_of_maine_orono
CATEGORIES:Conferences/Seminars/Lectures
END:VEVENT
END:VCALENDAR