Ion microprobe U-Th-Pb dating of Shergotty phosphates

Details Ion microprobe U-Th-Pb dating of Shergotty phosphates Ion microprobe U-Th-Pb dating of Shergotty phosphates

Mar 2000

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2000m%26ps...35..341s&link_type=abstract

Meteoritics & Planetary Science, vol. 35, no. 2, pp. 341-346 (2000).

Physics

13

Scientific paper

We report ion microprobe U-Th-Pb dating of Shergotty phosphates by means of the SHRIMP instrumention recently installed at Hiroshima University, Japan. Ten analyses of whitlockite (merrillite) and three analyses of apatite indicate a 238U/206Pb isochron age of 225 ± 200 Ma and a Tera-Wasserburg concordia constrained linear 3-D isochron age of 217 ± 110 Ma in the 238U/206Pb-207Pb/206Pb-204Pb/206Pb diagram. These ages agree well with the 232Th-208Pb age of 189 ± 83 Ma, suggesting primary crystallization or a shock metamorphic event defined the formation age of the phosphate minerals. The average of the later two ages, 204 ± 68 Ma, is consistent with the previously published Rb-Sr age of 165 ± 11 Ma and U-Th-Pb age of ~200 Ma. These show marginal agreement with the 40Ar-39Ar age of 254 ± 10 Ma, but are significantly different from the Sm-Nd age of 360 ± 16 Ma. Taking into account the closure temperature of the U-Pb system in apatite, we suggest the time when a temperature of about 900 oC was last experienced by Shergotty is 204 ± 68 Ma.

Affiliated with

Also associated with

No associations

Rating

Ion microprobe U-Th-Pb dating of Shergotty phosphates does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Ion microprobe U-Th-Pb dating of Shergotty phosphates, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ion microprobe U-Th-Pb dating of Shergotty phosphates will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1299200