Yamakawa, Akane et al. (2010) Chromium isotope systematic of achondrites: Chronology and isotopic heterogeneity of the inner solar system bodies, The Astrophysical Journal, 720, 150-154, doi: 10.1088/0004-637X/720/1/150. < 20191206145100-095776 > pub

Map on Earth or stone. Places and analyses are shown.

  • abstract:

    The standard planetary formation models assume that primitive materials, such as carbonaceous chondrites, are the precursor materials of evolved planetesimals. Past chronological studies have revealed that planetesimals of several hundred kilometers in size, such as the Howardite-Eucrite-Diogenite (HED) parent body (Vesta) and angrite parent body, began their differentiation as early as ~3 million years of the solar system formation, and continued for at least several million years. However, the timescale of planetesimal formation in distinct regions of the inner solar system, as well as the isotopic characteristics of the reservoirs from which they evolved, remains unclear. Here we present the first report for the precise 53Mn-53Cr ages of monomict ureilites. Chemically separated phases from one monomict ureilite (NWA 766) yielded the Mn-Cr age of 4564.60 ± 0.67 Ma, identical within error to the oldest age preserved in other achondrites, such as angrites and eucrites. The 54Cr isotopic data for this and seven additional bulk ureilites show homogeneous ε54Cr of ~–0.9, a value distinct from other achondrites and chondrites. Using the ε54Cr signatures of Earth, Mars, and Vesta (HED), we noticed a linear decrease in the ε54Cr value with the heliocentric distance in the inner region of the solar system. If this trend can be extrapolated into the outer asteroid belt, the ε54Cr signatures of monomict ureilites will place the position of the ureilite parent body at ~2.8 AU. These observations imply that the differentiation of achondrite parent bodies began nearly simultaneously at ~4565 Ma in different regions of the inner solar system. The distinct ε54Cr value between ureilite and carbonaceous chondrite also implies that a genetic link commonly proposed between the two is unlikely.

  • doi: 10.1088/0004-637X/720/1/150
  • modified at 17 h ago
Nwa766 thumb NWA 766 < 20110530154945-282-392 >pub
  • classification: achondrite
  • physical-form: chunk
  • quantity (g): 0.0
  • status: (zero)
  • modified at 2019-04-10
El gouanem thumb El Gouanem < 20071205074914.en >pub
  • classification: achondrite
  • physical-form: aliquot
  • status: (unknown)
  • description: A piece of El Gouanem was purchased at http://meteoritemarket.com in early 2007, and its original weight is 5.7 g.Price was $342.00. Leave Meteorites 0 <20120119113950-135-463> and enter Meteorites 0 <20120119113950-135-463> on 2015-08-28.
  • modified at 2020-01-06
Nwa 1241 thumb NWA 1241 < 20071205074928.en >pub
  • classification: achondrite
  • physical-form: aliquot
  • status: (unknown)
  • description: A piece of NWA 1241 was purchased at http://mars.li in early 2007, and its original weight is 8 g. Price was $960.00.
  • modified at 2019-12-06
Nwa 2376 thumb NWA 2376 < 20071205074912.en >pub
  • classification: achondrite
  • physical-form: aliquot
  • status: (unknown)
  • description: A piece of NWA 2376 was purchased at http://arizonaskiesmeteorites.com in early 2007, and its original weight is 18.0 g.Price was $703.20.
  • modified at 2020-01-06
Dar al gani 868 thumb Dar al Gani 868 < 20071205074925.en >pub
  • classification: achondrite
  • physical-form: aliquot
  • status: (unknown)
  • description: A piece of Dar al Gani 868 was purchased at http://mars.li in early 2007, and its original weight is 3.7 g.Price was $721.50.
  • modified at 2020-01-06
Dhofar836 thumb Dhofar 836 < 20071205074922.en >pub
  • classification: achondrite
  • physical-form: aliquot
  • quantity (g): 0.0
  • status: (zero)
  • description: A piece of Dhofar 836 was purchased at http://mars.li in early 2007, and its original weight is 7.5 g.Price was $300.00.
  • modified at 2020-01-06
Dhofar 132 thumb Dhofar 132 < 20071205074907.en >pub
  • classification: achondrite
  • physical-form: aliquot
  • quantity (g): 0.0
  • status: (zero)
  • description: A piece of Dhofar 132 was purchased at http://www.nyrockman.com/ in early 2007, and its original weight is 637 g. Price was $5000.00.
  • modified at 2020-01-06
Dar al gani 340 thumb Dar al Gani 340 < 20071205074909.en >pub
  • classification: achondrite
  • physical-form: aliquot
  • quantity (g): 0.0
  • status: (zero)
  • description: A piece of Dar al Gani 340 was purchased at http://www.nyrockman.com/ in early 2007, and its original weight is 3.3 g. Price was $148.50.
  • modified at 2020-01-06
name box-type global-id
binder of Chromium isotope systematic of achondrites: Chronology and isotopic heterogeneity of the inner solar system bodies pub container 20191209143410-105505
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El Gouanem pub TIMS Thermo-Fisher Triton 6 20191209141702-918412
Dhofar 836 pub TIMS Thermo-Fisher Triton 6 20191209141702-046184
Dhofar 132 pub TIMS Thermo-Fisher Triton 6 20191209141702-999066
NWA 2376 pub TIMS Thermo-Fisher Triton 6 20191209141703-737783
Dar al Gani 340 pub TIMS Thermo-Fisher Triton 6 20191209141703-721440
Dar al Gani 868 pub TIMS Thermo-Fisher Triton 6 20191209141703-062643
NWA766-LE4 pub TIMS Thermo-Fisher Triton 3 20191209141700-531672
NWA766-WR pub TIMS Thermo-Fisher Triton 6 20191209141701-048783
NWA766-sil pub TIMS Thermo-Fisher Triton 3 20191209141701-500589
NWA766-sp pub TIMS Thermo-Fisher Triton 3 20191209141700-495148
NWA766-LE3 pub TIMS Thermo-Fisher Triton 3 20191209141659-417918
NWA766-LE1 pub TIMS Thermo-Fisher Triton 3 20191209141658-901979
NWA766-LE2 pub TIMS Thermo-Fisher Triton 3 20191209141659-055666
NWA 1241-LE6 pub TIMS Thermo-Fisher Triton 3 20191209141702-853457
NWA 1241-LE5 pub TIMS Thermo-Fisher Triton 3 20191209141702-185976
NWA 1241-LE4 pub TIMS Thermo-Fisher Triton 3 20191209141701-836547
NWA 1241-LE2 pub TIMS Thermo-Fisher Triton 3 20191209141701-926014
NWA766-LE6 pub TIMS Thermo-Fisher Triton 3 20191209141700-204728
NWA766-LE5 pub TIMS Thermo-Fisher Triton 3 20191209141700-675941
NWA 1241-WR pub TIMS Thermo-Fisher Triton 6 20191209141702-705516
NWA 1241-LE3 pub TIMS Thermo-Fisher Triton 3 20191209141701-587466
NWA 1241-LE1 pub TIMS Thermo-Fisher Triton 3 20191209141701-022223
name spots global-id
caption ID assembly stone
Table 1. 55Mn/52Cr Ratios and ε54Cr Ratios in Ureilites pub 20191209141804-213468 Mn-Cr (Yamakawa et al., 2010) 22
manual
  • name
  • Yamakawa, Akane
  • Makishima, Akio
  • Nakamura, E.
  • Yamashita, Katsuyuki