<abstract xmlns="http://www.w3.org/1999/xhtml">Enstatite in Yamato 86004 classified as EH melt rock shows cathodoluminescence (CL) zonation as arranged in a concentric pattern from within outward blue, light blue, red and non-CL areas (fusion crust). The zonation observed in the meteorite results from different distribution ratio of the enstatite with various CL colors. CL spectra of the enstatite have two broad emission bands at around 400 nm in the blue region and at around 670 nm in a red region. The emission components obtained by a spectral deconvolution can be assigned to three defect centers (2.73, 3.13–3.15 and 3.77 eV) in a blue region and to impurity centers of Cr3+ ion (1.71 eV) and Mn2+ ion (1.86–1.91 eV) in a red region. According to the CL related to structural defects in the enstatite, blue-CL enstatite might be originally formed from the melt by a quenching from the melt on the surface of parent body. The enstatite with light blue and red CL might be thermally altered from blue-CL enstatite with phase transitions during a flash heating when the meteorite passed through the atmosphere. Therefore, the color CL zonation reflects a thermal history recorded in the meteorite.</abstract>

Enstatite in Yamato 86004 classified as EH melt rock shows cathodoluminescence (CL) zonation as arranged in a concentric pattern from within outward blue, light blue, red and non-CL areas (fusion crust). The zonation observed in the meteorite results from different distribution ratio of the enstatite with various CL colors. CL spectra of the enstatite have two broad emission bands at around 400 nm in the blue region and at around 670 nm in a red region. The emission components obtained by a spectral deconvolution can be assigned to three defect centers (2.73, 3.13–3.15 and 3.77 eV) in a blue region and to impurity centers of Cr3+ ion (1.71 eV) and Mn2+ ion (1.86–1.91 eV) in a red region. According to the CL related to structural defects in the enstatite, blue-CL enstatite might be originally formed from the melt by a quenching from the melt on the surface of parent body. The enstatite with light blue and red CL might be thermally altered from blue-CL enstatite with phase transitions during a flash heating when the meteorite passed through the atmosphere. Therefore, the color CL zonation reflects a thermal history recorded in the meteorite.

Cathodoluminescence color zonation in the Antarctic meteorite (enstatite chondrite) of Yamato 86004

Department of Biosphere-Geosphere Science

Geochronometria

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Enstatite in Yamato 86004 classified as EH melt rock shows cathodoluminescence (CL) zonation as arranged in a concentric pattern from within outward blue,...

	Enstatite in zone 1	Enstatite in zone 2	Enstatite in zone 3	Fusion crust in zone 4
SiO₂	59.80	59.96	59.20	53.90	wt.%
TiO₂	n.d.	0.01	n.d.	n.d.
Al₂O₃	0.11	0.10	0.07	4.24
FeO	0.43	0.11	0.60	30.60
Cr₂O₃	0.02	n.d.	0.02	0.39
MnO	n.d.	n.d.	0.04	0.94
MgO	39.81	39.74	39.48	5.05
CaO	0.26	0.28	0.24	3.55
NiO	0.01	0.01	0.06	n.d.
Na₂O	0.01	n.d.	n.d.	1.41
K₂O	0.01	0.01	0.01	n.d.
Total	100.46	100.22	99.73	100.00

Cathodoluminescence color zonation in the Antarctic meteorite (enstatite chondrite) of Yamato 86004

Published Online: Jun 01, 2017

Page range: 136 - 141

Received: Mar 14, 2016

Accepted: Jan 11, 2017

DOI: https://doi.org/10.1515/geochr-2015-0053

Keywords
enstatite, cathodoluminescence, enstatite chondrite, Antarctic meteorite

© 2016 S. Ohgo.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Chemical compositions on an average of three analyses of the enstatite with different CL colors and fusion crust in each zone. n.d.: not detected.

Cathodoluminescence color zonation in the Antarctic meteorite (enstatite chondrite) of Yamato 86004

Published Online: Jun 01, 2017

Page range: 136 - 141

Received: Mar 14, 2016

Accepted: Jan 11, 2017

DOI: https://doi.org/10.1515/geochr-2015-0053

Keywordsenstatite, cathodoluminescence, enstatite chondrite, Antarctic meteorite

© 2016 S. Ohgo.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Chemical compositions on an average of three analyses of the enstatite with different CL colors and fusion crust in each zone. n.d.: not detected.

Keywords
enstatite, cathodoluminescence, enstatite chondrite, Antarctic meteorite