Bunburra Rockhole: Exploring the geology of a new differentiated asteroid

Bunburra Rockhole is the first recovered meteorite of the Desert Fireball Network. We expanded a bulk chemical study of the Bunburra Rockhole meteorite to include major, minor and trace element analyses, as well as oxygen and chromium isotopes, in several different pieces of the meteorite. This was...

Full description

Bibliographic Details
Main Authors: Benedix, Gretchen, Bland, Phil, Friedrich, J., Mittlefehldt, D., Sanborn, M., Yin, Q., Greenwood, R., Franchi, I., Bevan, Alexander
Format: Journal Article
Published: Pergamon 2017
Online Access:http://hdl.handle.net/20.500.11937/53287
_version_ 1848759108702830592
author Benedix, Gretchen
Bland, Phil
Friedrich, J.
Mittlefehldt, D.
Sanborn, M.
Yin, Q.
Greenwood, R.
Franchi, I.
Bevan, Alexander
author_facet Benedix, Gretchen
Bland, Phil
Friedrich, J.
Mittlefehldt, D.
Sanborn, M.
Yin, Q.
Greenwood, R.
Franchi, I.
Bevan, Alexander
author_sort Benedix, Gretchen
building Curtin Institutional Repository
collection Online Access
description Bunburra Rockhole is the first recovered meteorite of the Desert Fireball Network. We expanded a bulk chemical study of the Bunburra Rockhole meteorite to include major, minor and trace element analyses, as well as oxygen and chromium isotopes, in several different pieces of the meteorite. This was to determine the extent of chemical heterogeneity and constrain the origin of the meteorite. Minor and trace element analyses in all pieces are exactly on the basaltic eucrite trend. Major element analyses show a slight deviation from basaltic eucrite compositions, but not in any systematic pattern. New oxygen isotope analyses on 23 pieces of Bunburra Rockhole shows large variation in both d17O and d18O, and both are well outside the HED parent body fractionation line. We present the first Cr isotope results of this rock, which are also distinct from HEDs. Detailed computed tomographic scanning and back-scattered electron mapping do not indicate the presence of any other meteoritic contaminant (contamination is also unlikely based on trace element chemistry). We therefore conclude that Bunburra Rockhole represents a sample of a new differentiated asteroid, one that may have more variable oxygen isotopic compositions than 4 Vesta. The fact that Bunburra Rockhole chemistry falls on the eucrite trend perhaps suggests that multiple objects with basaltic crusts accreted in a similar region of the Solar System.
first_indexed 2025-11-14T09:54:39Z
format Journal Article
id curtin-20.500.11937-53287
institution Curtin University Malaysia
institution_category Local University
last_indexed 2025-11-14T09:54:39Z
publishDate 2017
publisher Pergamon
recordtype eprints
repository_type Digital Repository
spelling curtin-20.500.11937-532872017-10-20T03:15:30Z Bunburra Rockhole: Exploring the geology of a new differentiated asteroid Benedix, Gretchen Bland, Phil Friedrich, J. Mittlefehldt, D. Sanborn, M. Yin, Q. Greenwood, R. Franchi, I. Bevan, Alexander Bunburra Rockhole is the first recovered meteorite of the Desert Fireball Network. We expanded a bulk chemical study of the Bunburra Rockhole meteorite to include major, minor and trace element analyses, as well as oxygen and chromium isotopes, in several different pieces of the meteorite. This was to determine the extent of chemical heterogeneity and constrain the origin of the meteorite. Minor and trace element analyses in all pieces are exactly on the basaltic eucrite trend. Major element analyses show a slight deviation from basaltic eucrite compositions, but not in any systematic pattern. New oxygen isotope analyses on 23 pieces of Bunburra Rockhole shows large variation in both d17O and d18O, and both are well outside the HED parent body fractionation line. We present the first Cr isotope results of this rock, which are also distinct from HEDs. Detailed computed tomographic scanning and back-scattered electron mapping do not indicate the presence of any other meteoritic contaminant (contamination is also unlikely based on trace element chemistry). We therefore conclude that Bunburra Rockhole represents a sample of a new differentiated asteroid, one that may have more variable oxygen isotopic compositions than 4 Vesta. The fact that Bunburra Rockhole chemistry falls on the eucrite trend perhaps suggests that multiple objects with basaltic crusts accreted in a similar region of the Solar System. 2017 Journal Article http://hdl.handle.net/20.500.11937/53287 10.1016/j.gca.2017.03.030 Pergamon restricted
spellingShingle Benedix, Gretchen
Bland, Phil
Friedrich, J.
Mittlefehldt, D.
Sanborn, M.
Yin, Q.
Greenwood, R.
Franchi, I.
Bevan, Alexander
Bunburra Rockhole: Exploring the geology of a new differentiated asteroid
title Bunburra Rockhole: Exploring the geology of a new differentiated asteroid
title_full Bunburra Rockhole: Exploring the geology of a new differentiated asteroid
title_fullStr Bunburra Rockhole: Exploring the geology of a new differentiated asteroid
title_full_unstemmed Bunburra Rockhole: Exploring the geology of a new differentiated asteroid
title_short Bunburra Rockhole: Exploring the geology of a new differentiated asteroid
title_sort bunburra rockhole: exploring the geology of a new differentiated asteroid
url http://hdl.handle.net/20.500.11937/53287