Academic Journal
Orthopyroxene as a geospeedometer: Thermal history of Kapoeta, Old Homestead 001, and Hughes 002 howardites
| العنوان: | Orthopyroxene as a geospeedometer: Thermal history of Kapoeta, Old Homestead 001, and Hughes 002 howardites |
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| المؤلفون: | Domeneghetti, M. c., Molin, G. m., Triscari, M., Zema, M. |
| المصدر: | Meteoritics & Planetary Science ; volume 35, issue 2, page 347-354 ; ISSN 1086-9379 1945-5100 |
| بيانات النشر: | Wiley |
| سنة النشر: | 2000 |
| المجموعة: | Wiley Online Library (Open Access Articles via Crossref) |
| الوصف: | — Single crystals of orthopyroxene from small fragments of the Kapoeta, Old Homestead 001, and Hughes 002 howardites were studied by x‐ray diffraction and microprobe analyses. The Fe‐Mg equilibrium distribution coefficients k D of the crystals were used to calculate the closure temperatures ( T c ) using the calibration by Stimpfl et al. (1999). The compositions, the presence of exsolved augite lamellae, and the T c values (from 365 to 385 °C) obtained for Kapoeta orthopyroxene s suggest that our fragment comes from a diogenitic cumulate clast. The more Fe‐rich composition, the absence of exsolved lamellae, and the higher T c values (from 583 to 605 °C) measured in the Old Homestead 001 orthopyroxenes suggest that this fragment comes from a cumulitic clast affected by fast cooling at high temperature. For the Hughes 002 orthopyroxenes, close in composition to Old Homestead 001, the different T c values (339, 358, and 607 °C) recorded by the various crystals and the presence of augite lamellae in the crystals with the lowest T c support the hypothesis that this howardite sample is an unheated breccia containing a mixture of cumulitic orthopyroxenes with different thermal histories. |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| DOI: | 10.1111/j.1945-5100.2000.tb01780.x |
| الاتاحة: | http://dx.doi.org/10.1111/j.1945-5100.2000.tb01780.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1945-5100.2000.tb01780.x https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1945-5100.2000.tb01780.x |
| Rights: | http://onlinelibrary.wiley.com/termsAndConditions#vor |
| رقم الانضمام: | edsbas.C8DF17E8 |
| قاعدة البيانات: | BASE |
| DOI: | 10.1111/j.1945-5100.2000.tb01780.x |
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